text:
BEL 20

The BEL 20 is the benchmark stock market index of Euronext Brussels. It tracks the performance of 20 most capitalized and liquid stocks traded in Belgium. In general, the index consists of a minimum of 10 and a maximum of 20 companies traded at the Brussels Stock Exchange. Since 20 June 2011, the BEL20 has contained 20 listings, with the exception a one-month period in May–June 2018 when Ablynx stock was removed following the takeover by Sanofi, only to be replaced mid June by arGEN-X.

Rules
The composition of the BEL 20 index is reviewed annually based on closing prices on the last Friday in February. These changes are effective after the third Friday of March. In addition to meeting a set of criteria demanding a company be "representative of the Belgian equity market", at least 15% of its shares must be considered free float in order to qualify for the index. In addition, a candidate for inclusion must possess a free float market capitalisation (in Euros) of at least 300000 times the price of the index on the last trading day of December. The minimum requirement for an existing constituent to remain in the index is a market cap of 200000 times the index value. At each annual review, the weights of companies in the index are capped at 15%, but range freely with share price subsequently. The BEL20 is a capitalization-weighted index. Its record high is 4756,82 set on 23 May 2007.

Annual Returns
The following table shows the annual development of the BEL 20 Index, which was calculated back to 1990.

Constituents
The following 20 stocks make up the BEL 20 as of 22 March 2021.

 * – Weightings accurate on 31 December 2023.

title: BEL 20


text:
Zuidas

The Zuidas (literally South Axis in Dutch) is a rapidly developing business district in the city of Amsterdam in the Netherlands. The Zuidas is also known as the 'Financial Mile'. It lies between the rivers Amstel and Schinkel along the ringway A10. The greatest influences for the development of the Zuidas are La Défense in Paris and Canary Wharf in London. In size it can best be compared with the Noordruimte/Espace Nord in Brussels.

In the future, the local Amsterdam Zuid railway station is planned to become the second main station in Amsterdam. It is expected to become the fifth busiest passenger station in the Netherlands, with connections to Schiphol Airport, Rotterdam, Antwerp, Brussels, and Paris via the Thalys, a high-speed rail. It will also connect to the German high-speed network, the ICE, via Utrecht and Arnhem.

The journey from the Zuidas to Amsterdam Airport Schiphol takes approximately 8 minutes. Future development could include an underground line directly to the airport. Another high-speed link has been proposed by a consortium of companies between Amsterdam Airport Schiphol, Amsterdam Zuid and the city of Almere.

The Zuidas already has good underground connections to other business areas with the Circle Line. With the completion of the North South line, the Zuidas has an even better connection to the city center. The city council is not only investigating expanding the underground network to Amsterdam Airport Schiphol but also upgrading the hybrid metro/light rail line that stops at Amsterdam Zuid.

Large multinationals such as ABN-Amro and Akzo Nobel have their headquarters in this new area. After Brexit, European Medicines Agency moved from London to Zuidas.

Between 1998 and 2004, the World Trade Center Amsterdam was renovated and expanded. In 2005, floor space in Zuidas amounted to 3000000 m2. Rapid expansion of Zuidas continued after 2005.

The main infrastructural axis (Ring-A10) is scheduled to be tunnelled, transforming the entire area. This would add an estimated €2 billion to the cost of the plan.

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/

title: Zuidas


text:
Isotopes of scandium

Naturally occurring scandium (21Sc) is composed of one stable isotope, 45Sc. Twenty-five radioisotopes have been characterized, with the most stable being 46Sc with a half-life of 83.8 days, 47Sc with a half-life of 3.35 days, and 48Sc with a half-life of 43.7 hours and 44Sc with a half-life of 3.97 hours. All the remaining isotopes have half-lives that are less than four hours, and the majority of these have half-lives that are less than two minutes, the least stable being proton unbound 39Sc with a half-life shorter than 300 nanoseconds. This element also has 13 meta states with the most stable being 44m2Sc (t1/2 58.6 h).

The isotopes of scandium range in atomic weight from 39 u (39Sc) to 62 u (62Sc). The primary decay mode at masses lower than the only stable isotope, 45Sc, is beta-plus or electron capture, and the primary mode at masses above it is beta-minus. The primary decay products at atomic weights below 45Sc are calcium isotopes and the primary products from higher atomic weights are titanium isotopes.

List of isotopes

 * 39Sc
 * style="text-align:right" | 21
 * style="text-align:right" | 18
 * 38.984790(26)
 * <300 ns
 * p
 * 38Ca
 * (7/2−)#
 * rowspan=3|40Sc
 * rowspan=3 style="text-align:right" | 21
 * rowspan=3 style="text-align:right" | 19
 * rowspan=3|39.977967(3)
 * rowspan=3|182.3(7) ms
 * β+ (99.54%)
 * 40Ca
 * rowspan=3|4−
 * rowspan=3|
 * β+, p (.44%)
 * 39K
 * β+, α (.017%)
 * 36Ar
 * 41Sc
 * style="text-align:right" | 21
 * style="text-align:right" | 20
 * 40.96925113(24)
 * 596.3(17) ms
 * β+
 * 41Ca
 * 7/2−
 * 42Sc
 * style="text-align:right" | 21
 * style="text-align:right" | 21
 * 41.96551643(29)
 * 681.3(7) ms
 * β+
 * 42Ca
 * 0+
 * style="text-indent:1em" | 42mSc
 * colspan="3" style="text-indent:2em" | 616.28(6) keV
 * 61.7(4) s
 * β+
 * 42Ca
 * (7, 5, 6)+
 * 43Sc
 * style="text-align:right" | 21
 * style="text-align:right" | 22
 * 42.9611507(20)
 * 3.891(12) h
 * β+
 * 43Ca
 * 7/2−
 * style="text-indent:1em" | 43m1Sc
 * colspan="3" style="text-indent:2em" | 151.4(2) keV
 * 438(7) μs
 * 3/2+
 * style="text-indent:1em" | 43m2Sc
 * colspan="3" style="text-indent:2em" | 3123.2(3) keV
 * 470(4) ns
 * (19/2)−
 * 44Sc
 * style="text-align:right" | 21
 * style="text-align:right" | 23
 * 43.9594028(19)
 * 3.97(4) h
 * β+
 * 44Ca
 * 2+
 * style="text-indent:1em" | 44m1Sc
 * colspan="3" style="text-indent:2em" | 67.8680(14) keV
 * 154.2(8) ns
 * 1−
 * rowspan=2 style="text-indent:1em" | 44m2Sc
 * rowspan=2 colspan="3" style="text-indent:2em" | 270.95(20) keV
 * rowspan=2|58.61(10) h
 * IT (98.8%)
 * 44Sc
 * rowspan=2| 6+
 * rowspan=2|
 * β+ (1.2%)
 * 44Ca
 * style="text-indent:1em" | 44m3Sc
 * colspan="3" style="text-indent:2em" | 146.224(22) keV
 * 50.4(7) μs
 * 0−
 * 45Sc
 * style="text-align:right" | 21
 * style="text-align:right" | 24
 * 44.9559119(9)
 * colspan=3 align=center|Stable
 * 7/2−
 * 1.0000
 * style="text-indent:1em" | 45mSc
 * colspan="3" style="text-indent:2em" | 12.40(5) keV
 * 318(7) ms
 * IT
 * 45Sc
 * 3/2+
 * 46Sc
 * style="text-align:right" | 21
 * style="text-align:right" | 25
 * 45.9551719(9)
 * 83.79(4) d
 * β−
 * 46Ti
 * 4+
 * style="text-indent:1em" | 46m1Sc
 * colspan="3" style="text-indent:2em" | 52.011(1) keV
 * 9.4(8) μs
 * 6+
 * style="text-indent:1em" | 46m2Sc
 * colspan="3" style="text-indent:2em" | 142.528(7) keV
 * 18.75(4) s
 * IT
 * 46Sc
 * 1−
 * 47Sc
 * style="text-align:right" | 21
 * style="text-align:right" | 26
 * 46.9524075(22)
 * 3.3492(6) d
 * β−
 * 47Ti
 * 7/2−
 * style="text-indent:1em" | 47mSc
 * colspan="3" style="text-indent:2em" | 766.83(9) keV
 * 272(8) ns
 * (3/2)+
 * 48Sc
 * style="text-align:right" | 21
 * style="text-align:right" | 27
 * 47.952231(6)
 * 43.67(9) h
 * β−
 * 48Ti
 * 6+
 * 49Sc
 * style="text-align:right" | 21
 * style="text-align:right" | 28
 * 48.950024(4)
 * 57.2(2) min
 * β−
 * 49Ti
 * 7/2−
 * 50Sc
 * style="text-align:right" | 21
 * style="text-align:right" | 29
 * 49.952188(17)
 * 102.5(5) s
 * β−
 * 50Ti
 * 5+
 * rowspan=2 style="text-indent:1em" | 50mSc
 * rowspan=2 colspan="3" style="text-indent:2em" | 256.895(10) keV
 * rowspan=2|350(40) ms
 * IT (97.5%)
 * 50Sc
 * rowspan=2|2+, 3+
 * rowspan=2|
 * β− (2.5%)
 * 50Ti
 * 51Sc
 * style="text-align:right" | 21
 * style="text-align:right" | 30
 * 50.953603(22)
 * 12.4(1) s
 * β−
 * 51Ti
 * (7/2)−
 * 52Sc
 * style="text-align:right" | 21
 * style="text-align:right" | 31
 * 51.95668(21)
 * 8.2(2) s
 * β−
 * 52Ti
 * 3(+)
 * rowspan=2|53Sc
 * rowspan=2 style="text-align:right" | 21
 * rowspan=2 style="text-align:right" | 32
 * rowspan=2|52.95961(32)#
 * rowspan=2|2.4(0.6) s
 * β− (>99.9%)
 * 53Ti
 * rowspan=2|(7/2−)#
 * rowspan=2|
 * β−, n (<.1%)
 * 52Ti
 * rowspan=2|54Sc
 * rowspan=2 style="text-align:right" | 21
 * rowspan=2 style="text-align:right" | 33
 * rowspan=2|53.96326(40)
 * rowspan=2|260(30) ms
 * β− (>99.9%)
 * 54Ti
 * rowspan=2|3+#
 * rowspan=2|
 * β−, n (<.1%)
 * 53Ti
 * style="text-indent:1em" | 54mSc
 * colspan="3" style="text-indent:2em" | 110(3) keV
 * 7(5) μs
 * (5+)
 * rowspan=2|55Sc
 * rowspan=2 style="text-align:right" | 21
 * rowspan=2 style="text-align:right" | 34
 * rowspan=2|54.96824(79)
 * rowspan=2|0.115(15) s
 * β− (>99.9%)
 * 55Ti
 * rowspan=2|7/2−#
 * rowspan=2|
 * β−, n (<.1%)
 * 54Ti
 * 56Sc
 * style="text-align:right" | 21
 * style="text-align:right" | 35
 * 55.97287(75)#
 * 35(5) ms
 * β−
 * 56Ti
 * (1+)
 * 57Sc
 * style="text-align:right" | 21
 * style="text-align:right" | 36
 * 56.97779(75)#
 * 13(4) ms
 * β−
 * 57Ti
 * 7/2−#
 * 58Sc
 * style="text-align:right" | 21
 * style="text-align:right" | 37
 * 57.98371(86)#
 * 12(5) ms
 * β−
 * 58Ti
 * (3+)#
 * rowspan=2|59Sc
 * rowspan=2 style="text-align:right" | 21
 * rowspan=2 style="text-align:right" | 38
 * rowspan=2|58.98922(97)#
 * rowspan=2|10# ms
 * β−, n
 * 58Ti
 * rowspan=2|7/2−#
 * rowspan=2|
 * β−
 * 59Ti
 * rowspan=3|60Sc
 * rowspan=3 style="text-align:right" | 21
 * rowspan=3 style="text-align:right" | 39
 * rowspan=3|59.99571(97)#
 * rowspan=3|3# ms (>620 ns)
 * β−
 * 60Ti
 * rowspan=3|3+#
 * rowspan=3|
 * β−, n
 * 59Ti
 * β−, 2n
 * 58Ti
 * rowspan=3|61Sc
 * rowspan=3 style="text-align:right" | 21
 * rowspan=3 style="text-align:right" | 40
 * rowspan=3|61.001(600)#
 * rowspan=3|2# ms (>620 ns)
 * β−
 * 61Ti
 * rowspan=3|7/2-#
 * rowspan=3|
 * β−, n
 * 60Ti
 * β−, 2n
 * 59Ti
 * rowspan=3|62Sc
 * rowspan=3 style="text-align:right" | 21
 * rowspan=3 style="text-align:right" | 41
 * rowspan=3|62.00785(64)#
 * rowspan=3|2# ms (>400 ns)
 * β−?
 * 62Ti
 * rowspan=3|
 * rowspan=3|
 * β−, n?
 * 61Ti
 * β−, 2n?
 * 60Ti
 * style="text-align:right" | 21
 * style="text-align:right" | 35
 * 55.97287(75)#
 * 35(5) ms
 * β−
 * 56Ti
 * (1+)
 * 57Sc
 * style="text-align:right" | 21
 * style="text-align:right" | 36
 * 56.97779(75)#
 * 13(4) ms
 * β−
 * 57Ti
 * 7/2−#
 * 58Sc
 * style="text-align:right" | 21
 * style="text-align:right" | 37
 * 57.98371(86)#
 * 12(5) ms
 * β−
 * 58Ti
 * (3+)#
 * rowspan=2|59Sc
 * rowspan=2 style="text-align:right" | 21
 * rowspan=2 style="text-align:right" | 38
 * rowspan=2|58.98922(97)#
 * rowspan=2|10# ms
 * β−, n
 * 58Ti
 * rowspan=2|7/2−#
 * rowspan=2|
 * β−
 * 59Ti
 * rowspan=3|60Sc
 * rowspan=3 style="text-align:right" | 21
 * rowspan=3 style="text-align:right" | 39
 * rowspan=3|59.99571(97)#
 * rowspan=3|3# ms (>620 ns)
 * β−
 * 60Ti
 * rowspan=3|3+#
 * rowspan=3|
 * β−, n
 * 59Ti
 * β−, 2n
 * 58Ti
 * rowspan=3|61Sc
 * rowspan=3 style="text-align:right" | 21
 * rowspan=3 style="text-align:right" | 40
 * rowspan=3|61.001(600)#
 * rowspan=3|2# ms (>620 ns)
 * β−
 * 61Ti
 * rowspan=3|7/2-#
 * rowspan=3|
 * β−, n
 * 60Ti
 * β−, 2n
 * 59Ti
 * rowspan=3|62Sc
 * rowspan=3 style="text-align:right" | 21
 * rowspan=3 style="text-align:right" | 41
 * rowspan=3|62.00785(64)#
 * rowspan=3|2# ms (>400 ns)
 * β−?
 * 62Ti
 * rowspan=3|
 * rowspan=3|
 * β−, n?
 * 61Ti
 * β−, 2n?
 * 60Ti
 * rowspan=3|62Sc
 * rowspan=3 style="text-align:right" | 21
 * rowspan=3 style="text-align:right" | 41
 * rowspan=3|62.00785(64)#
 * rowspan=3|2# ms (>400 ns)
 * β−?
 * 62Ti
 * rowspan=3|
 * rowspan=3|
 * β−, n?
 * 61Ti
 * β−, 2n?
 * 60Ti
 * β−, 2n?
 * 60Ti
 * 60Ti

title: Isotopes of scandium


text:
Isotopes of titanium

Naturally occurring titanium (22Ti) is composed of five stable isotopes; 46Ti, 47Ti, 48Ti, 49Ti and 50Ti with 48Ti being the most abundant (73.8% natural abundance). Twenty-one radioisotopes have been characterized, with the most stable being 44Ti with a half-life of 60 years, 45Ti with a half-life of 184.8 minutes, 51Ti with a half-life of 5.76 minutes, and 52Ti with a half-life of 1.7 minutes. All of the remaining radioactive isotopes have half-lives that are less than 33 seconds, and the majority of these have half-lives that are less than half a second.

The isotopes of titanium range in atomic mass from 39.00 u (39Ti) to 64.00 u (64Ti). The primary decay mode for isotopes lighter than the stable isotopes (lighter than 46Ti) is β+ and the primary mode for the heavier ones (heavier than 50Ti) is β−; their respective decay products are scandium isotopes and the primary products after are vanadium isotopes.

List of isotopes

 * rowspan=3|39Ti
 * rowspan=3 style="text-align:right" | 22
 * rowspan=3 style="text-align:right" | 17
 * rowspan=3|39.00161(22)#
 * rowspan=3|31(4) ms [31(+6-4) ms]
 * β+, p (85%)
 * 38Ca
 * rowspan=3|3/2+#
 * rowspan=3|
 * rowspan=3|
 * β+ (15%)
 * 39Sc
 * β+, 2p (<.1%)
 * 37K
 * rowspan=2|40Ti
 * rowspan=2 style="text-align:right" | 22
 * rowspan=2 style="text-align:right" | 18
 * rowspan=2|39.99050(17)
 * rowspan=2|53.3(15) ms
 * β+ (56.99%)
 * 40Sc
 * rowspan=2|0+
 * rowspan=2|
 * rowspan=2|
 * β+, p (43.01%)
 * 39Ca
 * rowspan=2|41Ti
 * rowspan=2 style="text-align:right" | 22
 * rowspan=2 style="text-align:right" | 19
 * rowspan=2|40.98315(11)#
 * rowspan=2|80.4(9) ms
 * β+, p (>99.9%)
 * 40Ca
 * rowspan=2|3/2+
 * rowspan=2|
 * rowspan=2|
 * β+ (<.1%)
 * 41Sc
 * 42Ti
 * style="text-align:right" | 22
 * style="text-align:right" | 20
 * 41.973031(6)
 * 199(6) ms
 * β+
 * 42Sc
 * 0+
 * 43Ti
 * style="text-align:right" | 22
 * style="text-align:right" | 21
 * 42.968522(7)
 * 509(5) ms
 * β+
 * 43Sc
 * 7/2−
 * style="text-indent:1em" | 43m1Ti
 * colspan="3" style="text-indent:2em" | 313.0(10) keV
 * 12.6(6) μs
 * (3/2+)
 * style="text-indent:1em" | 43m2Ti
 * colspan="3" style="text-indent:2em" | 3066.4(10) keV
 * 560(6) ns
 * (19/2−)
 * 44Ti
 * style="text-align:right" | 22
 * style="text-align:right" | 22
 * 43.9596901(8)
 * 60.0(11) y
 * EC
 * 44Sc
 * 0+
 * 45Ti
 * style="text-align:right" | 22
 * style="text-align:right" | 23
 * 44.9581256(11)
 * 184.8(5) min
 * β+
 * 45Sc
 * 7/2−
 * 46Ti
 * style="text-align:right" | 22
 * style="text-align:right" | 24
 * 45.9526316(9)
 * colspan=3 align=center|Stable
 * 0+
 * 0.0825(3)
 * 47Ti
 * style="text-align:right" | 22
 * style="text-align:right" | 25
 * 46.9517631(9)
 * colspan=3 align=center|Stable
 * 5/2−
 * 0.0744(2)
 * 48Ti
 * style="text-align:right" | 22
 * style="text-align:right" | 26
 * 47.9479463(9)
 * colspan=3 align=center|Stable
 * 0+
 * 0.7372(3)
 * 49Ti
 * style="text-align:right" | 22
 * style="text-align:right" | 27
 * 48.9478700(9)
 * colspan=3 align=center|Stable
 * 7/2−
 * 0.0541(2)
 * 50Ti
 * style="text-align:right" | 22
 * style="text-align:right" | 28
 * 49.9447912(9)
 * colspan=3 align=center|Stable
 * 0+
 * 0.0518(2)
 * 51Ti
 * style="text-align:right" | 22
 * style="text-align:right" | 29
 * 50.946615(1)
 * 5.76(1) min
 * β−
 * 51V
 * 3/2−
 * 52Ti
 * style="text-align:right" | 22
 * style="text-align:right" | 30
 * 51.946897(8)
 * 1.7(1) min
 * β−
 * 52V
 * 0+
 * 53Ti
 * style="text-align:right" | 22
 * style="text-align:right" | 31
 * 52.94973(11)
 * 32.7(9) s
 * β−
 * 53V
 * (3/2)−
 * 54Ti
 * style="text-align:right" | 22
 * style="text-align:right" | 32
 * 53.95105(13)
 * 1.5(4) s
 * β−
 * 54V
 * 0+
 * 55Ti
 * style="text-align:right" | 22
 * style="text-align:right" | 33
 * 54.95527(16)
 * 490(90) ms
 * β−
 * 55V
 * 3/2−#
 * rowspan=2|56Ti
 * rowspan=2 style="text-align:right" | 22
 * rowspan=2 style="text-align:right" | 34
 * rowspan=2|55.95820(21)
 * rowspan=2|164(24) ms
 * β− (>99.9%)
 * 56V
 * rowspan=2|0+
 * rowspan=2|
 * rowspan=2|
 * β−, n (<.1%)
 * 55V
 * rowspan=2|57Ti
 * rowspan=2 style="text-align:right" | 22
 * rowspan=2 style="text-align:right" | 35
 * rowspan=2|56.96399(49)
 * rowspan=2|60(16) ms
 * β− (>99.9%)
 * 57V
 * rowspan=2|5/2−#
 * rowspan=2|
 * rowspan=2|
 * β−, n (<.1%)
 * 56V
 * 58Ti
 * style="text-align:right" | 22
 * style="text-align:right" | 36
 * 57.96697(75)#
 * 54(7) ms
 * β−
 * 58V
 * 0+
 * 59Ti
 * style="text-align:right" | 22
 * style="text-align:right" | 37
 * 58.97293(75)#
 * 30(3) ms
 * β−
 * 59V
 * (5/2−)#
 * 60Ti
 * style="text-align:right" | 22
 * style="text-align:right" | 38
 * 59.97676(86)#
 * 22(2) ms
 * β−
 * 60V
 * 0+
 * rowspan=2|61Ti
 * rowspan=2 style="text-align:right" | 22
 * rowspan=2 style="text-align:right" | 39
 * rowspan=2|60.98320(97)#
 * rowspan=2|10# ms [>300 ns]
 * β−
 * 61V
 * rowspan=2|1/2−#
 * rowspan=2|
 * rowspan=2|
 * β−, n
 * 60V
 * 62Ti
 * style="text-align:right" | 22
 * style="text-align:right" | 40
 * 61.98749(97)#
 * 10# ms
 * 0+
 * 63Ti
 * style="text-align:right" | 22
 * style="text-align:right" | 41
 * 62.99442(107)#
 * 3# ms
 * 1/2−#
 * 64Ti
 * style="text-align:right" | 22
 * style="text-align:right" | 42
 * 63.998410(640)#
 * 5# ms [>620 ns]
 * 0+
 * rowspan=2|
 * β−, n (<.1%)
 * 56V
 * 58Ti
 * style="text-align:right" | 22
 * style="text-align:right" | 36
 * 57.96697(75)#
 * 54(7) ms
 * β−
 * 58V
 * 0+
 * 59Ti
 * style="text-align:right" | 22
 * style="text-align:right" | 37
 * 58.97293(75)#
 * 30(3) ms
 * β−
 * 59V
 * (5/2−)#
 * 60Ti
 * style="text-align:right" | 22
 * style="text-align:right" | 38
 * 59.97676(86)#
 * 22(2) ms
 * β−
 * 60V
 * 0+
 * rowspan=2|61Ti
 * rowspan=2 style="text-align:right" | 22
 * rowspan=2 style="text-align:right" | 39
 * rowspan=2|60.98320(97)#
 * rowspan=2|10# ms [>300 ns]
 * β−
 * 61V
 * rowspan=2|1/2−#
 * rowspan=2|
 * rowspan=2|
 * β−, n
 * 60V
 * 62Ti
 * style="text-align:right" | 22
 * style="text-align:right" | 40
 * 61.98749(97)#
 * 10# ms
 * 0+
 * 63Ti
 * style="text-align:right" | 22
 * style="text-align:right" | 41
 * 62.99442(107)#
 * 3# ms
 * 1/2−#
 * 64Ti
 * style="text-align:right" | 22
 * style="text-align:right" | 42
 * 63.998410(640)#
 * 5# ms [>620 ns]
 * 0+
 * 0+
 * 63Ti
 * style="text-align:right" | 22
 * style="text-align:right" | 41
 * 62.99442(107)#
 * 3# ms
 * 1/2−#
 * 64Ti
 * style="text-align:right" | 22
 * style="text-align:right" | 42
 * 63.998410(640)#
 * 5# ms [>620 ns]
 * 0+
 * 1/2−#
 * 64Ti
 * style="text-align:right" | 22
 * style="text-align:right" | 42
 * 63.998410(640)#
 * 5# ms [>620 ns]
 * 0+
 * 63.998410(640)#
 * 5# ms [>620 ns]
 * 0+
 * 0+
 * 0+

Titanium-44
Titanium-44 (44Ti) is a radioactive isotope of titanium that undergoes electron capture to an excited state of scandium-44 with a half-life of 60 years, before the ground state of 44Sc and ultimately 44Ca are populated. Because titanium-44 can only undergo electron capture, its half-life increases with ionization and it becomes stable in its fully ionized state (that is, having a charge of +22).

Titanium-44 is produced in relative abundance in the alpha process in stellar nucleosynthesis and the early stages of supernova explosions. It is produced when calcium-40 fuses with an alpha particle (helium-4 nucleus) in a star's high-temperature environment; the resulting 44Ti nucleus can then fuse with another alpha particle to form chromium-48. The age of supernovae may be determined through measurements of gamma-ray emissions from titanium-44 and its abundance. It was observed in the Cassiopeia A supernova remnant and SN 1987A at a relatively high concentration, a consequence of delayed decay resulting from ionizing conditions.

title: Isotopes of titanium


text:
Isotopes of calcium

Calcium ($20$Ca) has 26 known isotopes, ranging from $35$Ca to $60$Ca. There are five stable isotopes ($40$Ca, $42$Ca, $43$Ca, $44$Ca and $46$Ca), plus one isotope ($48$Ca) with such a long half-life that it is for all practical purposes stable. The most abundant isotope, $40$Ca, as well as the rare $46$Ca, are theoretically unstable on energetic grounds, but their decay has not been observed. Calcium also has a cosmogenic isotope, $41$Ca, with half-life 99,400 years. Unlike cosmogenic isotopes that are produced in the air, $41$Ca is produced by neutron activation of $40$Ca. Most of its production is in the upper metre of the soil column, where the cosmogenic neutron flux is still strong enough. $41$Ca has received much attention in stellar studies because it decays to $41$K, a critical indicator of solar system anomalies. The most stable artificial isotopes are $45$Ca with half-life 163 days and $47$Ca with half-life 4.5 days. All other calcium isotopes have half-lives of minutes or less.

$40$Ca comprises about 97% of natural calcium. $40$Ca, like $40$Ar, is a decay product of $40$K. While K–Ar dating has been used extensively in the geological sciences, the prevalence of $40$Ca in nature has impeded its use in dating. Techniques using mass spectrometry and a double spike isotope dilution have been used for K–Ca age dating.

List of isotopes

 * rowspan=3|$35$Ca
 * rowspan=3 style="text-align:right" | 20
 * rowspan=3 style="text-align:right" | 15
 * rowspan=3|35.00557(22)#
 * rowspan=3|25.7(2) ms
 * β$+$, p (95.8%)
 * $34$Ar
 * rowspan=3|1/2+#
 * rowspan=3|
 * rowspan=3|
 * β$+$, 2p (4.2%)
 * $33$Cl
 * β$+$ (rare)
 * $35$K
 * rowspan=2|$36$Ca
 * rowspan=2 style="text-align:right" | 20
 * rowspan=2 style="text-align:right" | 16
 * rowspan=2|35.993074(43)
 * rowspan=2|100.9(13) ms
 * β$+$, p (51.2%)
 * $35$Ar
 * rowspan=2|0+
 * rowspan=2|
 * rowspan=2|
 * β$+$ (48.8%)
 * $36$K
 * rowspan=2|$37$Ca
 * rowspan=2 style="text-align:right" | 20
 * rowspan=2 style="text-align:right" | 17
 * rowspan=2|36.98589785(68)
 * rowspan=2|181.0(9) ms
 * β$+$, p (76.8%)
 * $36$Ar
 * rowspan=2|3/2+
 * rowspan=2|
 * rowspan=2|
 * β$+$ (23.2%)
 * $37$K
 * $38$Ca
 * style="text-align:right" | 20
 * style="text-align:right" | 18
 * 37.97631922(21)
 * 443.70(25) ms
 * β$+$
 * $38$K
 * 0+
 * $39$Ca
 * style="text-align:right" | 20
 * style="text-align:right" | 19
 * 38.97071081(64)
 * 860.3(8) ms
 * β$+$
 * $39$K
 * 3/2+
 * $40$Ca
 * style="text-align:right" | 20
 * style="text-align:right" | 20
 * 39.962590850(22)
 * colspan=3 align=center|Observationally stable
 * 0+
 * 0.9694(16)
 * 0.96933–0.96947
 * $40$Ca
 * style="text-align:right" | 20
 * style="text-align:right" | 21
 * 40.96227791(15)
 * 9.94(15)×10$21$ y
 * EC
 * $41$K
 * 7/2−
 * Trace
 * $4$Ca
 * style="text-align:right" | 20
 * style="text-align:right" | 22
 * 41.95861778(16)
 * colspan=3 align=center|Stable
 * 0+
 * 0.00647(23)
 * 0.00646–0.00648
 * $41$Ca
 * style="text-align:right" | 20
 * style="text-align:right" | 23
 * 42.95876638(24)
 * colspan=3 align=center|Stable
 * 7/2−
 * 0.00135(10)
 * 0.00135–0.00135
 * $42$Ca
 * style="text-align:right" | 20
 * style="text-align:right" | 24
 * 43.95548149(35)
 * colspan=3 align=center|Stable
 * 0+
 * 0.0209(11)
 * 0.02082–0.02092
 * $43$Ca
 * style="text-align:right" | 20
 * style="text-align:right" | 25
 * 44.95618627(39)
 * 162.61(9) d
 * β$44$
 * $45$Sc
 * 7/2−
 * $−$Ca
 * style="text-align:right" | 20
 * style="text-align:right" | 26
 * 45.9536877(24)
 * colspan=3 align=center|Observationally stable
 * 0+
 * 4×10$45$
 * 4×10$46$–4×10$−$
 * $−$Ca
 * style="text-align:right" | 20
 * style="text-align:right" | 27
 * 46.9545411(24)
 * 4.536(3) d
 * β$46$
 * $−5$Sc
 * 7/2−
 * $−5$Ca
 * style="text-align:right" | 20
 * style="text-align:right" | 28
 * 47.952522654(18)
 * 5.6(10)×10$−5$ y|| β$47$β$−$
 * $47$Ti
 * 0+
 * 0.00187(21)
 * 0.00186–0.00188
 * $48$Ca
 * style="text-align:right" | 20
 * style="text-align:right" | 29
 * 48.95566263(19)
 * 8.718(6) min
 * β$19$
 * $−$Sc
 * 3/2−
 * $−$Ca
 * style="text-align:right" | 20
 * style="text-align:right" | 30
 * 49.9574992(17)
 * 13.45(5) s
 * β$−$
 * $48$Sc
 * 0+
 * rowspan=2|$+0.8 −0.6$Ca
 * rowspan=2 style="text-align:right" | 20
 * rowspan=2 style="text-align:right" | 31
 * rowspan=2|50.96099566(56)
 * rowspan=2|10.0(8) s
 * β$21$
 * $48$Sc
 * rowspan=2|3/2−
 * rowspan=2|
 * rowspan=2|
 * β$48$, n?
 * $48$Sc
 * rowspan=2|$49$Ca
 * rowspan=2 style="text-align:right" | 20
 * rowspan=2 style="text-align:right" | 32
 * rowspan=2|51.96321365(72)
 * rowspan=2|4.6(3) s
 * β$−$ (>98%)
 * $49$Sc
 * rowspan=2|0+
 * rowspan=2|
 * rowspan=2|
 * β$50$, n (<2%)
 * $−$Sc
 * rowspan=2|$50$Ca
 * rowspan=2 style="text-align:right" | 20
 * rowspan=2 style="text-align:right" | 33
 * rowspan=2|52.968451(47)
 * rowspan=2|461(90) ms
 * β$51$ (60%)
 * $−$Sc
 * rowspan=2|1/2−#
 * rowspan=2|
 * rowspan=2|
 * β$51$, n (40%)
 * $−$Sc
 * rowspan=3|$50$Ca
 * rowspan=3 style="text-align:right" | 20
 * rowspan=3 style="text-align:right" | 34
 * rowspan=3|53.972989(52)
 * rowspan=3|90(6) ms
 * β$52$
 * $−$Sc
 * rowspan=3|0+
 * rowspan=3|
 * rowspan=3|
 * β$52$, n?
 * $−$Sc
 * β$51$, 2n?
 * $53$Sc
 * rowspan=3|$−$Ca
 * rowspan=3 style="text-align:right" | 20
 * rowspan=3 style="text-align:right" | 35
 * rowspan=3|54.97998(17)
 * rowspan=3|22(2) ms
 * β$53$
 * $−$Sc
 * rowspan=3|5/2−#
 * rowspan=3|
 * rowspan=3|
 * β$52$, n?
 * $54$Sc
 * β$−$, 2n?
 * $54$Sc
 * rowspan=3|$−$Ca
 * rowspan=3 style="text-align:right" | 20
 * rowspan=3 style="text-align:right" | 36
 * rowspan=3|55.98550(27)
 * rowspan=3|11(2) ms
 * β$53$
 * $−$Sc
 * rowspan=3|0+
 * rowspan=3|
 * rowspan=3|
 * β$52$, n?
 * $55$Sc
 * β$−$, 2n?
 * $55$Sc
 * rowspan=3|$−$Ca
 * rowspan=3 style="text-align:right" | 20
 * rowspan=3 style="text-align:right" | 37
 * rowspan=3|56.99296(43)#
 * rowspan=3|8# ms [>620 ns]
 * β$54$?
 * $−$Sc
 * rowspan=3|5/2−#
 * rowspan=3|
 * rowspan=3|
 * β$53$, n?
 * $56$Sc
 * β$−$, 2n?
 * $56$Sc
 * rowspan=3|$−$Ca
 * rowspan=3 style="text-align:right" | 20
 * rowspan=3 style="text-align:right" | 38
 * rowspan=3|57.99836(54)#
 * rowspan=3|4# ms [>620 ns]
 * β$55$?
 * $−$Sc
 * rowspan=3|0+
 * rowspan=3|
 * rowspan=3|
 * β$54$, n?
 * $57$Sc
 * β$−$, 2n?
 * $57$Sc
 * rowspan=3|$−$Ca
 * rowspan=3 style="text-align:right" | 20
 * rowspan=3 style="text-align:right" | 39
 * rowspan=3|59.00624(64)#
 * rowspan=3|5# ms [>400 ns]
 * β$56$?
 * $−$Sc
 * rowspan=3|5/2−#
 * rowspan=3|
 * rowspan=3|
 * β$55$, n?
 * $58$Sc
 * β$−$, 2n?
 * $58$Sc
 * rowspan=3|$−$Ca
 * rowspan=3 style="text-align:right" | 20
 * rowspan=3 style="text-align:right" | 40
 * rowspan=3|60.01181(75)#
 * rowspan=3|2# ms [>400 ns]
 * β$57$?
 * $−$Sc
 * rowspan=3|0+
 * rowspan=3|
 * rowspan=3|
 * β$56$, n?
 * $59$Sc
 * β$−$, 2n?
 * $59$Sc
 * rowspan=3|5/2−#
 * rowspan=3|
 * rowspan=3|
 * β$−$, n?
 * $58$Sc
 * β$−$, 2n?
 * $57$Sc
 * rowspan=3|$60$Ca
 * rowspan=3 style="text-align:right" | 20
 * rowspan=3 style="text-align:right" | 38
 * rowspan=3|57.99836(54)#
 * rowspan=3|4# ms [>620 ns]
 * β$−$?
 * $60$Sc
 * rowspan=3|0+
 * rowspan=3|
 * rowspan=3|
 * β$−$, n?
 * $59$Sc
 * β$−$, 2n?
 * $58$Sc
 * rowspan=3|$19$Ca
 * rowspan=3 style="text-align:right" | 20
 * rowspan=3 style="text-align:right" | 39
 * rowspan=3|59.00624(64)#
 * rowspan=3|5# ms [>400 ns]
 * β$48$?
 * $48$Sc
 * rowspan=3|5/2−#
 * rowspan=3|
 * rowspan=3|
 * β$34$, n?
 * $37$Sc
 * β$43$, 2n?
 * $48$Sc
 * rowspan=3|$249$Ca
 * rowspan=3 style="text-align:right" | 20
 * rowspan=3 style="text-align:right" | 40
 * rowspan=3|60.01181(75)#
 * rowspan=3|2# ms [>400 ns]
 * β$245$?
 * $48$Sc
 * rowspan=3|0+
 * rowspan=3|
 * rowspan=3|
 * β$59$, n?
 * $60$Sc
 * β$70$, 2n?
 * $70$Sc
 * β$59$?
 * $60$Sc
 * rowspan=3|0+
 * rowspan=3|
 * rowspan=3|
 * β$59$, n?
 * $60$Sc
 * β$68$, 2n?
 * $60$Sc
 * β$58, 60$, 2n?
 * $60$Sc

Calcium-48

Calcium-48 is a doubly magic nucleus with 28 neutrons; unusually neutron-rich for a light primordial nucleus. It decays via double beta decay with an extremely long half-life of about 6.4×10$62$ years, though single beta decay is also theoretically possible. This decay can analyzed with the sd nuclear shell model, and it is more energetic (4.27 MeV) than any other double beta decay. It can also be used as a precursor for neutron-rich and superheavy nuclei.

Calcium-60
Calcium-60 is the heaviest known isotope. First observed in 2018 at Riken alongside $56$Ca and seven isotopes of other elements, its existence suggests that there are additional even-N isotopes of calcium up to at least $58$Ca, while $62$Ca is probably the last bound isotope with odd N. Earlier predictions had estimated the neutron drip line to occur at $64$Ca, with $56, 58$Ca unbound.

In the neutron-rich region, N = 40 becomes a magic number, so $60$Ca was considered early on to be a possibly doubly magic nucleus, as is observed for the ⇭⇭⇭Ni isotone.  However, subsequent spectroscopic measurements of the nearby nuclides ⇭⇭⇭Ca, ⇭⇭⇭Ca, and ⇭⇭⇭Ti instead predict that it should lie on the island of inversion known to exist around ⇭⇭⇭Cr.

title: Isotopes of calcium


text:
Isotopes of potassium

Potassium has 24 known isotopes from  to  as well as, as well as an unconfirmed report of. Three of those isotopes occur naturally: the two stable forms (93.3%) and  (6.7%), and a very long-lived radioisotope Potassium-40 (0.012%)

Naturally occurring radioactive decays with a half-life of 1.248×109 years. 89% of those decays are to stable Calcium by beta decay, whilst 11% are to Argon by either electron capture or positron emission. This latter decay branch has produced an isotopic abundance of argon on Earth which differs greatly from that seen in gas giants and stellar spectra. has the longest known half-life for any positron-emitter nuclide. The long half-life of this primordial radioisotope is caused by a highly spin-forbidden transition: has a nuclear spin of 4, while both of its decay daughters are even–even isotopes with spins of 0.

occurs in natural potassium in sufficient quantity that large bags of potassium chloride commercial salt substitutes can be used as a radioactive source for classroom demonstrations. is the largest source of natural radioactivity in healthy animals and humans, greater even than carbon-14. In a human body of 70 kg mass, about 4,400 nuclei of decay per second.

The decay of to  is used in potassium-argon dating of rocks. Minerals are dated by measurement of the concentration of potassium and the amount of radiogenic that has accumulated. Typically, the method assumes that the rocks contained no argon at the time of formation and all subsequent radiogenic argon (i.e., ) was retained. has also been extensively used as a radioactive tracer in studies of weathering.

All other potassium isotopes have half-lives under a day, most under a minute. The least stable is, a three-proton emitter discovered in 2019; its half-life was measured to be shorter than 10 picoseconds.

Stable potassium isotopes have been used for several nutrient cycling studies since potassium is a macronutrient required for life.

List of isotopes

 * style="text-align:right" | 19
 * style="text-align:right" | 12
 * 31.03678(32)#
 * <10 ps
 * 3p
 * 28S
 * 3/2+#
 * rowspan=2|35K
 * rowspan=2 style="text-align:right" | 19
 * rowspan=2 style="text-align:right" | 16
 * rowspan=2|34.98800541(55)
 * rowspan=2|175.2(19) ms
 * β+ (99.63%)
 * 35Ar
 * rowspan=2|3/2+
 * rowspan=2|
 * rowspan=2|
 * β+, p (0.37%)
 * 34Cl
 * rowspan=3|36K
 * rowspan=3 style="text-align:right" | 19
 * rowspan=3 style="text-align:right" | 17
 * rowspan=3|35.98130189(35)
 * rowspan=3|341(3) ms
 * β+ (99.95%)
 * 36Ar
 * rowspan=3|2+
 * rowspan=3|
 * rowspan=3|
 * β+, p (0.048%)
 * 35Cl
 * β+, α (0.0034%)
 * 32S
 * 37K
 * style="text-align:right" | 19
 * style="text-align:right" | 18
 * 36.97337589(10)
 * 1.23651(94) s
 * β+
 * 37Ar
 * 3/2+
 * 38K
 * style="text-align:right" | 19
 * style="text-align:right" | 19
 * 37.96908111(21)
 * 7.651(19) min
 * β+
 * 38Ar
 * 3+
 * rowspan=2 style="text-indent:1em" | 38m1K
 * rowspan=2 colspan="3" style="text-indent:2em" | 130.15(4) keV
 * rowspan=2|924.35(12) ms
 * β+ (99.97%)
 * 38Ar
 * rowspan=2|0+
 * rowspan=2|
 * rowspan=2|
 * IT (0.0330%)
 * 38K
 * style="text-indent:1em" | 38m2K
 * colspan="3" style="text-indent:2em" | 3458.10(17) keV
 * 21.95(11) μs
 * IT
 * 38K
 * (7)+
 * 39K
 * style="text-align:right" | 19
 * style="text-align:right" | 20
 * 38.9637064848(49)
 * colspan=3 align=center|Stable
 * 3/2+
 * 0.932581(44)
 * rowspan=3|40K
 * rowspan=3 style="text-align:right" | 19
 * rowspan=3 style="text-align:right" | 21
 * rowspan=3|39.963998165(60)
 * rowspan=3|1.248(3)×109 y
 * β− (89.28%)
 * 40Ca
 * rowspan=3|4−
 * rowspan=3|1.17(1)×10−4
 * rowspan=3|
 * EC (10.72%)
 * rowspan=2|40Ar
 * β+ (0.001%)
 * style="text-indent:1em" | 40mK
 * colspan="3" style="text-indent:2em" | 1643.638(11) keV
 * 336(12) ns
 * IT
 * 40K
 * 0+
 * 41K
 * style="text-align:right" | 19
 * style="text-align:right" | 22
 * 40.9618252561(40)
 * colspan=3 align=center|Stable
 * 3/2+
 * 0.067302(44)
 * 42K
 * style="text-align:right" | 19
 * style="text-align:right" | 23
 * 41.96240231(11)
 * 12.355(7) h
 * β−
 * 42Ca
 * 2−
 * Trace
 * 43K
 * style="text-align:right" | 19
 * style="text-align:right" | 24
 * 42.96073470(44)
 * 22.3(1) h
 * β−
 * 43Ca
 * 3/2+
 * style="text-indent:1em" | 43mK
 * colspan=3 style="text-indent:2em" | 738.30(6) keV
 * 200(5) ns
 * IT
 * 43K
 * 7/2−
 * 44K
 * style="text-align:right" | 19
 * style="text-align:right" | 25
 * 43.96158698(45)
 * 22.13(19) min
 * β−
 * 44Ca
 * 2−
 * 45K
 * style="text-align:right" | 19
 * style="text-align:right" | 26
 * 44.96069149(56)
 * 17.8(6) min
 * β−
 * 45Ca
 * 3/2+
 * 46K
 * style="text-align:right" | 19
 * style="text-align:right" | 27
 * 45.96198158(78)
 * 96.30(8) s
 * β−
 * 46Ca
 * 2−
 * 47K
 * style="text-align:right" | 19
 * style="text-align:right" | 28
 * 46.9616616(15)
 * 17.38(3) s
 * β−
 * 47Ca
 * 1/2+
 * rowspan=2|48K
 * rowspan=2 style="text-align:right" | 19
 * rowspan=2 style="text-align:right" | 29
 * rowspan=2|47.96534118(83)
 * rowspan=2|6.83(14) s
 * β− (98.86%)
 * 48Ca
 * rowspan=2|1−
 * rowspan=2|
 * rowspan=2|
 * β−, n (1.14%)
 * 47Ca
 * rowspan=2|49K
 * rowspan=2 style="text-align:right" | 19
 * rowspan=2 style="text-align:right" | 30
 * rowspan=2|48.96821075(86)
 * rowspan=2|1.26(5) s
 * β−, n (86%)
 * 48Ca
 * rowspan=2|1/2+
 * rowspan=2|
 * rowspan=2|
 * β− (14%)
 * 49Ca
 * rowspan=3|50K
 * rowspan=3 style="text-align:right" | 19
 * rowspan=3 style="text-align:right" | 31
 * rowspan=3|49.9723800(83)
 * rowspan=3|472(4) ms
 * β− (71.4%)
 * 50Ca
 * rowspan=3|0−
 * rowspan=3|
 * rowspan=3|
 * β−, n (28.6%)
 * 49Ca
 * β−, 2n?
 * 48Ca
 * style="text-indent:1em" | 50mK
 * colspan=3 style="text-indent:2em" | 172.0(4) keV
 * 125(40) ns
 * IT
 * 50K
 * (2−)
 * rowspan=3|51K
 * rowspan=3 style="text-align:right" | 19
 * rowspan=3 style="text-align:right" | 32
 * rowspan=3|50.975828(14)
 * rowspan=3|365(5) ms
 * β−, n (65%)
 * 50Ca
 * rowspan=3|3/2+
 * rowspan=3|
 * rowspan=3|
 * β− (35%)
 * 51Ca
 * β−, 2n?
 * 49Ca
 * rowspan=3|52K
 * rowspan=3 style="text-align:right" | 19
 * rowspan=3 style="text-align:right" | 33
 * rowspan=3|51.981602(36)
 * rowspan=3|110(4) ms
 * β−, n (72.2%)
 * 51Ca
 * rowspan=3|2−#
 * rowspan=3|
 * rowspan=3|
 * β− (25.5%)
 * 52Ca
 * β−, 2n (2.3%)
 * 50Ca
 * rowspan=3|53K
 * rowspan=3 style="text-align:right" | 19
 * rowspan=3 style="text-align:right" | 34
 * rowspan=3|52.98680(12)
 * rowspan=3|30(5) ms
 * β−, n (64%)
 * 52Ca
 * rowspan=3|3/2+
 * rowspan=3|
 * rowspan=3|
 * β− (26%)
 * 53Ca
 * β−, 2n (10%)
 * 51Ca
 * rowspan=3|54K
 * rowspan=3 style="text-align:right" | 19
 * rowspan=3 style="text-align:right" | 35
 * rowspan=3|53.99447(43)#
 * rowspan=3|10(5) ms
 * β−
 * 54Ca
 * rowspan=3|2−#
 * rowspan=3|
 * rowspan=3|
 * β−, n?
 * 53Ca
 * β−, 2n?
 * 52Ca
 * rowspan=3|55K
 * rowspan=3 style="text-align:right" | 19
 * rowspan=3 style="text-align:right" | 36
 * rowspan=3|55.00051(54)#
 * rowspan=3|10# ms [>620 ns]
 * β−?
 * 55Ca
 * rowspan=3|3/2+#
 * rowspan=3|
 * rowspan=3|
 * β−, n?
 * 54Ca
 * β−, 2n?
 * 54Ca
 * rowspan=3|56K
 * rowspan=3 style="text-align:right" | 19
 * rowspan=3 style="text-align:right" | 37
 * rowspan=3|56.00857(64)#
 * rowspan=3|5# ms [>620 ns]
 * β−?
 * 56Ca
 * rowspan=3|2−#
 * rowspan=3|
 * rowspan=3|
 * β−, n?
 * 55Ca
 * β−, 2n?
 * 54Ca
 * rowspan=3|57K
 * rowspan=3 style="text-align:right" | 19
 * rowspan=3 style="text-align:right" | 38
 * rowspan=3|57.01517(64)#
 * rowspan=3|2# ms [>400 ns]
 * β−?
 * 57Ca
 * rowspan=3|3/2+#
 * rowspan=3|
 * rowspan=3|
 * β−, n?
 * 56Ca
 * β−, 2n?
 * 55Ca
 * rowspan=3|59K
 * rowspan=3 style="text-align:right" | 19
 * rowspan=3 style="text-align:right" | 40
 * rowspan=3|59.03086(86)#
 * rowspan=3|1# ms [>400 ns]
 * β−?
 * 59Ca
 * rowspan=3|3/2+#
 * rowspan=3|
 * rowspan=3|
 * β−, n?
 * 58Ca
 * β−, 2n?
 * 57Ca
 * rowspan=3|54K
 * rowspan=3 style="text-align:right" | 19
 * rowspan=3 style="text-align:right" | 35
 * rowspan=3|53.99447(43)#
 * rowspan=3|10(5) ms
 * β−
 * 54Ca
 * rowspan=3|2−#
 * rowspan=3|
 * rowspan=3|
 * β−, n?
 * 53Ca
 * β−, 2n?
 * 52Ca
 * rowspan=3|55K
 * rowspan=3 style="text-align:right" | 19
 * rowspan=3 style="text-align:right" | 36
 * rowspan=3|55.00051(54)#
 * rowspan=3|10# ms [>620 ns]
 * β−?
 * 55Ca
 * rowspan=3|3/2+#
 * rowspan=3|
 * rowspan=3|
 * β−, n?
 * 54Ca
 * β−, 2n?
 * 54Ca
 * rowspan=3|56K
 * rowspan=3 style="text-align:right" | 19
 * rowspan=3 style="text-align:right" | 37
 * rowspan=3|56.00857(64)#
 * rowspan=3|5# ms [>620 ns]
 * β−?
 * 56Ca
 * rowspan=3|2−#
 * rowspan=3|
 * rowspan=3|
 * β−, n?
 * 55Ca
 * β−, 2n?
 * 54Ca
 * rowspan=3|57K
 * rowspan=3 style="text-align:right" | 19
 * rowspan=3 style="text-align:right" | 38
 * rowspan=3|57.01517(64)#
 * rowspan=3|2# ms [>400 ns]
 * β−?
 * 57Ca
 * rowspan=3|3/2+#
 * rowspan=3|
 * rowspan=3|
 * β−, n?
 * 56Ca
 * β−, 2n?
 * 55Ca
 * rowspan=3|59K
 * rowspan=3 style="text-align:right" | 19
 * rowspan=3 style="text-align:right" | 40
 * rowspan=3|59.03086(86)#
 * rowspan=3|1# ms [>400 ns]
 * β−?
 * 59Ca
 * rowspan=3|3/2+#
 * rowspan=3|
 * rowspan=3|
 * β−, n?
 * 58Ca
 * β−, 2n?
 * 57Ca
 * rowspan=3 style="text-align:right" | 19
 * rowspan=3 style="text-align:right" | 40
 * rowspan=3|59.03086(86)#
 * rowspan=3|1# ms [>400 ns]
 * β−?
 * 59Ca
 * rowspan=3|3/2+#
 * rowspan=3|
 * rowspan=3|
 * β−, n?
 * 58Ca
 * β−, 2n?
 * 57Ca
 * β−, 2n?
 * 57Ca

title: Isotopes of potassium


text:
Isotopes of argon

Argon (18Ar) has 26 known isotopes, from 29Ar to 54Ar, of which three are stable (36Ar, 38Ar, and 40Ar). On the Earth, 40Ar makes up 99.6% of natural argon. The longest-lived radioactive isotopes are 39Ar with a half-life of 268 years, 42Ar with a half-life of 32.9 years, and 37Ar with a half-life of 35.04 days. All other isotopes have half-lives of less than two hours, and most less than one minute.

The naturally occurring 40K, with a half-life of 1.248 years, decays to stable 40Ar by electron capture (10.72%) and by positron emission (0.001%), and also transforms to stable 40Ca via beta decay (89.28%). These properties and ratios are used to determine the age of rocks through potassium–argon dating.

Despite the trapping of 40Ar in many rocks, it can be released by melting, grinding, and diffusion. Almost all of the argon in the Earth's atmosphere is the product of 40K decay, since 99.6% of Earth atmospheric argon is 40Ar, whereas in the Sun and presumably in primordial star-forming clouds, argon consists of < 15% 38Ar and mostly (85%) 36Ar. Similarly, the ratio of the three isotopes 36Ar:38Ar:40Ar in the atmospheres of the outer planets is measured to be 8400:1600:1.

In the Earth's atmosphere, radioactive 39Ar (half-life 268(8) years) is made by cosmic ray activity, primarily from 40Ar. In the subsurface environment, it is also produced through neutron capture by 39K or alpha emission by calcium. The content of 39Ar in natural argon is measured to be of (8.0±0.6)×10−16 g/g, or (1.01±0.08) Bq/kg of 36, 38, 40Ar. The content of 42Ar (half-life 33 years) in the Earth's atmosphere is lower than 6×10−21 parts per part of 36, 38, 40Ar. Many endeavors require argon depleted in the cosmogenic isotopes, known as depleted argon. Lighter radioactive isotopes can decay to different elements (usually chlorine) while heavier ones decay to potassium.

36Ar, in the form of argon hydride, was detected in the Crab Nebula supernova remnant during 2013. This was the first time a noble molecule was detected in outer space.

37Ar is a synthetic radionuclide that is created via neutron capture of 40Ca followed by alpha particle emission, as a result of subsurface nuclear explosions. It has a half-life of 35 days.

List of isotopes

 * 29Ar
 * style="text-align:right" | 18
 * style="text-align:right" | 11
 * 29.04076(47)#
 * 2p
 * 27S
 * 5/2+#
 * 30Ar
 * style="text-align:right" | 18
 * style="text-align:right" | 12
 * 30.02369(19)#
 * <10 ps
 * 2p
 * 28S
 * 0+
 * rowspan=7|31Ar
 * rowspan=7 style="text-align:right" | 18
 * rowspan=7 style="text-align:right" | 13
 * rowspan=7|31.01216(22)#
 * rowspan=7|15.0(3) ms
 * β+, p (68.3%)
 * 30S
 * rowspan=7|5/2+
 * rowspan=7|
 * rowspan=7|
 * β+ (22.63%)
 * 31Cl
 * β+, 2p (9.0%)
 * 29P
 * β+, 3p (0.07%)
 * 28Si
 * β+, p, α? (<0.38%)
 * 26Si
 * β+, α? (<0.03%)
 * 27P
 * 2p? (<0.03%)
 * 29S
 * rowspan=2|32Ar
 * rowspan=2 style="text-align:right" | 18
 * rowspan=2 style="text-align:right" | 14
 * rowspan=2|31.9976378(19)
 * rowspan=2|98(2) ms
 * β+ (64.42%)
 * 32Cl
 * rowspan=2|0+
 * rowspan=2|
 * rowspan=2|
 * β+, p (35.58%)
 * 31S
 * rowspan=2|33Ar
 * rowspan=2 style="text-align:right" | 18
 * rowspan=2 style="text-align:right" | 15
 * rowspan=2|32.98992555(43)
 * rowspan=2|173.0(20) ms
 * β+ (61.3%)
 * 33Cl
 * rowspan=2|1/2+
 * rowspan=2|
 * rowspan=2|
 * β+, p (38.7%)
 * 32S
 * 34Ar
 * style="text-align:right" | 18
 * style="text-align:right" | 16
 * 33.980270092(83)
 * 846.46(35) ms
 * β+
 * 34Cl
 * 0+
 * 35Ar
 * style="text-align:right" | 18
 * style="text-align:right" | 17
 * 34.97525772(73)
 * 1.7756(10) s
 * β+
 * 35Cl
 * 3/2+
 * 36Ar
 * style="text-align:right" | 18
 * style="text-align:right" | 18
 * 35.967545106(28)
 * colspan=3 align=center|Observationally Stable
 * 0+
 * 0.003336(210)
 * 37Ar
 * style="text-align:right" | 18
 * style="text-align:right" | 19
 * 36.96677630(22)
 * 35.011(19) d
 * EC
 * 37Cl
 * 3/2+
 * Trace
 * 38Ar
 * style="text-align:right" | 18
 * style="text-align:right" | 20
 * 37.96273210(21)
 * colspan=3 align=center|Stable
 * 0+
 * 0.000629(70)
 * 39Ar
 * style="text-align:right" | 18
 * style="text-align:right" | 21
 * 38.9643130(54)
 * $268.2$ y
 * β−
 * 39K
 * 7/2−
 * 40Ar
 * style="text-align:right" | 18
 * style="text-align:right" | 22
 * 39.9623831220(23)
 * colspan=3 align=center|Stable
 * 0+
 * 0.996035(250)
 * 41Ar
 * style="text-align:right" | 18
 * style="text-align:right" | 23
 * 40.96450057(37)
 * 109.61(4) min
 * β−
 * 41K
 * 7/2−
 * Trace
 * 42Ar
 * style="text-align:right" | 18
 * style="text-align:right" | 24
 * 41.9630457(62)
 * 32.9(11) y
 * β−
 * 42K
 * 0+
 * 43Ar
 * style="text-align:right" | 18
 * style="text-align:right" | 25
 * 42.9656361(57)
 * 5.37(6) min
 * β−
 * 43K
 * 5/2(−)
 * 44Ar
 * style="text-align:right" | 18
 * style="text-align:right" | 26
 * 43.9649238(17)
 * 11.87(5) min
 * β−
 * 44K
 * 0+
 * 45Ar
 * style="text-align:right" | 18
 * style="text-align:right" | 27
 * 44.96803973(55)
 * 21.48(15) s
 * β−
 * 45K
 * (5/2−,7/2−)
 * 46Ar
 * style="text-align:right" | 18
 * style="text-align:right" | 28
 * 45.9680392(25)
 * 8.4(6) s
 * β−
 * 46K
 * 0+
 * rowspan=2|47Ar
 * rowspan=2 style="text-align:right" | 18
 * rowspan=2 style="text-align:right" | 29
 * rowspan=2|46.9727671(13)
 * rowspan=2|1.23(3) s
 * β− (>99.8%)
 * 47K
 * rowspan=2|(3/2)−
 * rowspan=2|
 * rowspan=2|
 * β−, n? (<0.2%)
 * 46K
 * rowspan=2|48Ar
 * rowspan=2 style="text-align:right" | 18
 * rowspan=2 style="text-align:right" | 30
 * rowspan=2|47.976001(18)
 * rowspan=2|415(15) ms
 * β− (62%)
 * 48K
 * rowspan=2|0+
 * rowspan=2|
 * rowspan=2|
 * β−, n (38%)
 * 47K
 * rowspan=3|49Ar
 * rowspan=3 style="text-align:right" | 18
 * rowspan=3 style="text-align:right" | 31
 * rowspan=3|48.98169(43)#
 * rowspan=3|236(8) ms
 * β−
 * 49K
 * rowspan=3|3/2−#
 * rowspan=3|
 * rowspan=3|
 * β−, n (29%)
 * 48K
 * β−, 2n?
 * 47K
 * rowspan=3|50Ar
 * rowspan=3 style="text-align:right" | 18
 * rowspan=3 style="text-align:right" | 32
 * rowspan=3|49.98580(54)#
 * rowspan=3|106(6) ms
 * β− (63%)
 * 50K
 * rowspan=3|0+
 * rowspan=3|
 * rowspan=3|
 * β−, n (37%)
 * 49K
 * β−, 2n?
 * 48K
 * rowspan=3|51Ar
 * rowspan=3 style="text-align:right" | 18
 * rowspan=3 style="text-align:right" | 33
 * rowspan=3|50.99303(43)#
 * rowspan=3|30# ms [>200 ns]
 * β−?
 * 51K
 * rowspan=3|1/2−#
 * rowspan=3|
 * rowspan=3|
 * β−, n?
 * 50K
 * β−, 2n?
 * 49K
 * rowspan=3|52Ar
 * rowspan=3 style="text-align:right" | 18
 * rowspan=3 style="text-align:right" | 34
 * rowspan=3|51.99852(64)#
 * rowspan=3|40# ms [>620 ns]
 * β−?
 * 52K
 * rowspan=3|0+
 * rowspan=3|
 * rowspan=3|
 * β−, n?
 * 51K
 * β−, 2n?
 * 50K
 * rowspan=3|53Ar
 * rowspan=3 style="text-align:right" | 18
 * rowspan=3 style="text-align:right" | 35
 * rowspan=3|53.00729(75)#
 * rowspan=3|20# ms [>620 ns]
 * β−?
 * 53K
 * rowspan=3|5/2−#
 * rowspan=3|
 * rowspan=3|
 * β−, n?
 * 52K
 * β−, 2n?
 * 51K
 * rowspan=3|54Ar
 * rowspan=3 style="text-align:right" | 18
 * rowspan=3 style="text-align:right" | 36
 * rowspan=3|54.01348(86)#
 * rowspan=3|5# ms [>400 ns]
 * β−?
 * 54K
 * rowspan=3|0+
 * rowspan=3|
 * rowspan=3|
 * β−, n?
 * 53K
 * β−, 2n?
 * 52K
 * β−, n (37%)
 * 49K
 * β−, 2n?
 * 48K
 * rowspan=3|51Ar
 * rowspan=3 style="text-align:right" | 18
 * rowspan=3 style="text-align:right" | 33
 * rowspan=3|50.99303(43)#
 * rowspan=3|30# ms [>200 ns]
 * β−?
 * 51K
 * rowspan=3|1/2−#
 * rowspan=3|
 * rowspan=3|
 * β−, n?
 * 50K
 * β−, 2n?
 * 49K
 * rowspan=3|52Ar
 * rowspan=3 style="text-align:right" | 18
 * rowspan=3 style="text-align:right" | 34
 * rowspan=3|51.99852(64)#
 * rowspan=3|40# ms [>620 ns]
 * β−?
 * 52K
 * rowspan=3|0+
 * rowspan=3|
 * rowspan=3|
 * β−, n?
 * 51K
 * β−, 2n?
 * 50K
 * rowspan=3|53Ar
 * rowspan=3 style="text-align:right" | 18
 * rowspan=3 style="text-align:right" | 35
 * rowspan=3|53.00729(75)#
 * rowspan=3|20# ms [>620 ns]
 * β−?
 * 53K
 * rowspan=3|5/2−#
 * rowspan=3|
 * rowspan=3|
 * β−, n?
 * 52K
 * β−, 2n?
 * 51K
 * rowspan=3|54Ar
 * rowspan=3 style="text-align:right" | 18
 * rowspan=3 style="text-align:right" | 36
 * rowspan=3|54.01348(86)#
 * rowspan=3|5# ms [>400 ns]
 * β−?
 * 54K
 * rowspan=3|0+
 * rowspan=3|
 * rowspan=3|
 * β−, n?
 * 53K
 * β−, 2n?
 * 52K
 * rowspan=3 style="text-align:right" | 36
 * rowspan=3|54.01348(86)#
 * rowspan=3|5# ms [>400 ns]
 * β−?
 * 54K
 * rowspan=3|0+
 * rowspan=3|
 * rowspan=3|
 * β−, n?
 * 53K
 * β−, 2n?
 * 52K
 * β−, 2n?
 * 52K

title: Isotopes of argon


text:
List of districts of West Bengal

The Himalayas lies in the north of West Bengal and the Bay of Bengal is at the south. Between them, the river Ganga flows eastwards and its main distributary, the Hooghly River, flows south to reach the Bay of Bengal. The Siliguri Corridor, which connects North-East India with rest of the India, lies in the North Bengal region of the state. Geographically, West Bengal is divided into a variety of regions—Darjeeling Himalayan hill region, Terai and Dooars region, North Bengal plains, Rarh region, Western plateau and high lands, coastal plains, Sundarbans and the Ganga Delta.

In 1947, when India gained independence, the state of West Bengal was formed, with 14 districts, as per partition plan of the then Bengal province of British India. The former princely state Koch Bihar joined as a district on 26 January 1950, and the former French enclave Chandannagore joined as part of the Hooghly district in 1954. The States Reorganisation Act of 1956 led to addition of Purulia district to the state and to enlargement of West Dinajpur district. Later, larger districts such as West Dinajpur, 24 Parganas and Midnapore were bifurcated.

West Bengal is now divided into 23 districts which includes the newly formed Alipurduar district (formed on 25 June 2014), Kalimpong district (formed on 14 February 2017), Jhargram district (formed on 4 April 2017), and the splitting of the former Bardhaman district into Purba Bardhaman district and Paschim Bardhaman district (formed on 7 April 2017). The districts are grouped into five divisions.

Divisions are administered by Divisional Commissioners. Kolkata, the capital of the state, constitutes the Kolkata district. Other districts are further divided into administrative units such as subdivisions and blocks, administered by SDO and BDO, respectively. The Panchayati Raj has a three-tier structure in the state. The atomic unit is called a Gram Panchayat, which is the Panchayat organisation for a collection of villages. The block-level organisations are called Panchayat Samiti, and the district-level organisations are named Zilla Parishad.

The West Bengal cabinet has approved the creation of seven new districts on 1 August 2022. This will number district from 23 to 30. New Sundarban District from existing South 24 Parganas District, new Ichhamati District and Basirhat District from existing North 24 Parganas District. New Ranaghat District from existing Nadia District and Bishnupur District from existing Bankura district. While new Jangipur District and Berhampore district from existing Murshidabad District will be carved out.

Geography
West Bengal is bordered by three countries: Nepal, Bhutan and Bangladesh; and five Indian states: Sikkim, Bihar, Jharkhand, Odisha, and Assam. Sikkim and Bhutan are located to the north of the state, Nepal to the northwest, Bihar and Jharkhand in the west, Odisha in the southwest, the Bay of Bengal to the south, and Bangladesh and Assam are in the east. West Bengal is the only state of India that has both snowy mountains (Himalayas in the north) and sea beaches (on the coast of the Bay of Bengal in the south). In between them, the river Ganga enters the state from west, before it branches off into its main distributaries: the Hooghly River, which flows southwards to reach the Bay of Bengal, and the Padma River, which flows eastwards into Bangladesh.

The districts that are located at the north of the Ganga—Darjeeling, Jalpaiguri, Cooch Behar, Malda, Uttar Dinajpur, Dakshin Dinajpur, Alipurduar and Kalimpong — are often referred to collectively as North Bengal. Kalimpong is a newly added district of West Bengal. Geographically, this area is divided into the Darjeeling Himalayan hill region, the Terai and Dooars region, and the North Bengal plains. The Siliguri Corridor, also known as Chicken's Neck, which connects North-East India with rest of the India, lies in this region. The Indo-Bangladesh enclaves are either enclaves or exclaves of the Cooch Behar district or the Jalpaiguri district.

The districts on the south of the Ganges—Bankura, Paschim Bardhaman, Purba Bardhaman, Birbhum, Purulia, Murshidabad, Nadia, West Midnapore, Jhargram, East Midnapore, Hooghly, Howrah, Kolkata, North 24 Parganas and South 24 Parganas—constitute a variety of geographical regions such as the Rarh region, the Western plateau and high lands, the coastal plains, the Sunderbans and the Ganga Delta. Kolkata, the capital of the state, constitutes the Kolkata district.

The uninhabited South Talpatti Island, which surfaced in the Bay of Bengal in the 1970s near the Indo-Bangladesh border, is claimed by both India and Bangladesh.

History
After India gained independence in 1947, the province of Bengal was partitioned along religious lines. The western part remained in India (and was named West Bengal) while the eastern part joined newly formed Pakistan as a province called East Pakistan (later giving rise to Bangladesh in 1971). At the time of its creation in 1947, the state of West Bengal was divided into 14 districts—Bankura, Birbhum, Burdwan, Calcutta (Kolkata), Darjeeling, Jalpaiguri, Hooghly, Howrah, Malda, Midnapore, Murshidabad, Nadia, West Dinajpur and 24 Parganas. Cooch Behar district was a princely state named Koch Bihar till 20 August 1949, when the state formally agreed to join India. Transfer of administration was started on 12 September 1949 and was completed on 19 January 1950, when Cooch Behar became a district of West Bengal. Chandannagar, which was earlier part of the French India, had voted to join India in a plebiscite in 1949. Formally, it joined India in 1952 and finally became a part of the Hooghly district of West Bengal on 2 October 1954. The States Reorganisation Act of 1956 reorganised boundaries of the Indian states along linguistic lines. As this act was implemented, the then West Dinajpur district was enlarged with the addition of some areas from Bihar, and the Purulia district was formed on 1 November 1956 from parts of the Manbhum district of Bihar.

Later, some large districts were divided into smaller districts. On 1 March 1986, the district of 24 Parganas was bifurcated into two districts—the North 24 Parganas district and the South 24 Parganas district. On 1 April 1992, the West Dinajpur district was bifurcated into the Uttar Dinajpur district and the Dakshin Dinajpur district. On 1 January 2002, the erstwhile Midnapore district was bifurcated into the Purba Medinipur district and the Paschim Medinipur district.

Since 2007, the demand for a separate Gorkhaland state has been revived by the Gorkha Janmukti Morcha and its supporters in the Darjeeling hills. The Kamtapur People's Party and its supporters' movement for a separate Kamtapur state that covers the North Bengal has also gained momentum in the 2000s.

Administrative structure
A district is governed by a District Collector, who is better known as a District Magistrate (DM) in the state of West Bengal. A DM is an officer from either Indian Administrative Service (IAS) or West Bengal Civil Service (WBCS), and is appointed by the State Government of West Bengal. Each district is divided into subdivisions, except the Kolkata district, which contains urban area only, administered by Kolkata Municipal Corporation. A subdivision is governed by a sub-divisional magistrate (SDM), better known as a Sub-Divisional Officer (SDO). Other than urban units such as town municipalities, a subdivision contains 'community development blocks' (also known as CD blocks or blocks or Tehsil or Taluka). A block consists of urban units such as census towns and rural units called gram panchayats. A block is administered by a Block Development Officer (BDO),who is similar as Tehsildar and who is appointed by the Government of West Bengal.

A gram panchayat, which consists of a group of villages, is administered by a village council headed by a Pradhan. As per the West Bengal Panchayat Act, 1973, each Block has a Panchayat Samiti, whose members include the Pradhans of the constituent gram panchayats, and the MLAs from the block. A Panchayat Samiti is headed by a Sabhapati. The third tier of the Panchayati Raj is Zilla Parishad, a district level organisation with the Sabhapatis of the constituent Panchayat Samitis and the MLAs from the district as its members. A Zilla Parishad is headed by a Sabhadhipati. For the Darjeeling district, the Zilla Parishad has ceased to exist, but a similar organisation for the Siliguri subdivision exists, which is designated as a Mahakuma Parishad.

The Gorkha Hill Council, formed in 1988, administers three (out of four) subdivisions of the Darjeeling district: Darjeeling Sadar, Kalimpong and Kurseong. Gorkha Hill Council manages the departments of Public Health, Education, Public Works, Transport, Tourism, Market, Small scale industries, Agriculture, Agricultural waterways, Forest (except reserved forests), Water, Livestock, Vocational Training and Sports and Youth services. District administration of Darjeeling, which is still responsible for election, panchayat, law and order, revenue etc., also acts as an interface between the Council and the State Government.

A District Superintendent of Police, better known as a Superintendent of Police, heads the District Police organisation of West Bengal Police. This is as per the Police Act of 1861, which is applicable to the whole of India. The Superintendents of Police are officers of the Indian Police Service. For every subdivision, there is a Subdivision Police, headed by a Police officer of the rank of Assistant Superintendent of Police or Deputy Superintendent of Police. Under subdivisions, there are Police Circles, each headed by an Inspector of Police. A Police Circle consists of Police Stations, each headed by an Inspector of Police, or in case of rural areas, by a Sub-Inspector of Police.

The Calcutta High Court has the jurisdiction of the state of West Bengal. Though most of the districts have more courts other than a District Court, not every subdivision of the state has a Court.

A group of districts forms a division, which is administered by a 'Divisional Commissioner'. West Bengal is now divided in twenty three districts, grouped under five divisions:

Demographics
The following is a list of the basic demographic data for the districts of West Bengal at the time of the 2011 census by their population rank in India

Economy
The following is a list of basic economic data for the districts of West Bengal as of 2023–2024, the latest year for which data is available:

title: List of districts of West Bengal


text:
Prospect, New South Wales

Prospect is a suburb of Sydney, in the state of New South Wales, Australia. Prospect is located 32 kilometres west of the Sydney central business district in the local government area of the City of Blacktown and a small part of Cumberland City Council, is part of the Greater Western Sydney region. One of the oldest suburbs in Sydney, Prospect takes its name from the prominent nearby landmark of Prospect Hill - from the top of which people could get a prospect of (see a great distance) the surrounding countryside.

Initially a settlement for emancipated convicts, it later became a village. Since colonisation, settlers cleared larger areas of land to raise livestock, build churches, inns, schools, shops and a large reservoir. Naturalist Charles Darwin visited Prospect in January 1836, to observe the geology.

History
Prior to the arrival of the First Fleet in 1788, Prospect was inhabited by different groups of the Darug people including the Warmuli. The Aboriginals there were of the woods culture. As European settlement expanded, the aboriginal people's ability to pursue their traditional lifestyle, which was already severely limited, disappeared. Prospect Hill had been the frontier, which was the first, and perhaps only, area where large scale organised resistance by aboriginal people took place.

Lieutenant Watkin Tench most likely named Prospect Hill in April 1790. In July 1791, thirteen grants of land at Prospect were made to emancipated convicts. In January 1794 David Collins reported that the Prospect Hill farmers were the most productive in the colony.

Prospect became the boundary between colonists and indigenous Australians. Hostility grew until by 1797, where a state of guerrilla warfare existed between indigenous people and the settler communities at Prospect and Parramatta. The aboriginal people were led by their leader, Pemulwuy, a member of the Bidjigal tribe who occupied the land. Pemulwuy was the main leader of raids against the colony in the 1790s. In 1797 the war escalated; his guerrillas started regular raids on settlements in the Parramatta and Prospect Hill areas. British military expeditions failed to locate and capture Pemulwuy.

Shortly after 1808, William Lawson was appointed aide-de-camp to George Johnston, was granted 500 acre at Prospect and built a large house there, which he named Veteran Hall. In the 1880s most of the property was submerged in what is now Prospect reservoir.

On 30 January 2004 the eastern part of Prospect, which includes the quarry gap, became a new suburb called Pemulwuy containing the new housing estates of Lakeside and Nelson's Ridge and the industrial area within the oval-shaped ridge of Prospect Hill. So most of Prospect Hill is no longer within the suburb of Prospect.

Quarrying companies gradually took over more and more of Prospect Hill, mining the dolerite for use as roadstone until it was almost all gone and much of the hill with it. The Prospect quarry, which is now part of Pemulwuy, is formed by an intrusion of dolerite rock into Ashfield Shale. At least seven different rock types occur in the intrusion. The material is predominantly coarse grained picrite with olivine-dolerite and dolerite. Quarrying in the area last occurred in 2007. In the early 2010s, the 330ha quarry gap was transformed into light industry area. Prospect Highway now winds through the gap.

Heritage listings
Prospect has a number of heritage-listed sites, including:
 * Upper Canal System
 * Great Western Highway: Veteran Hall Remains
 * Ponds Road: St Bartholomew's Anglican Church and Cemetery
 * Reservoir Road: Former Great Western Road Alignment, Prospect
 * Reservoir Road: Prospect Reservoir
 * East of Reservoir: Prospect Reservoir Valve House
 * 385 Reservoir Road: Royal Cricketers Arms Inn
 * 23 Tarlington Place: Prospect Post Office
 * Clunies Ross Street: Prospect Hill
 * Reservoir Road: Prospect Hill Reservoir

Geography
Philip Gidley King mentions that the landscape of Prospect is "a very pleasant tract of country, which, from the distance the trees grew from each other, and the gentle hills and dales, and rising slopes covered with grass, appeared like a vast park. The soil from Rose Hill to Prospect-Hill is nearly alike, being a loam and clay." The tree cover was mainly the eucalypts, grey box and forest red gum. Spotted gum (Corymbia maculata) is also known to have occurred in the Prospect area.

Climate
Prospect has a humid subtropical climate (Cfa). Summer weather is warm to hot, and may be humid or dry. Like most of western Sydney, rainfall peaks in late summer to early autumn and more dry conditions occur between late winter and early spring, although rainfall can be erratic. The suburb gets 104.2 clear days annually, with the most sunniest days being in August (13.2) and least in February (5.0 days).

Prospect is usually a few degrees warmer than the Sydney CBD on most spring and summer days. In a few cases there has been a +10-degree differential (this is mostly when northwesterlies bring hot winds from the desert that raise temperatures up to +40 °C (104 °F). However, Prospect is usually a few degrees cooler on most nights of the year, because of its distance from the coast. The highest temperature recorded at Prospect was 45.1 °C (113.2 °F) on 7 January 2018. The lowest temperature recorded was −0.8 °C (30.6 °F) on 30 June 2010. Annually, there are 3.2 days where temperatures go below 2 °C.

Landmarks

 * Prospect Hill, Pemulwuy, is visible from many locations. It is a noticeable landmark of historical importance in the early settlement history of New South Wales and the suburb of Prospect takes its name from the hill. The hill is also the site of Prospect dolerite intrusion, which was composed mainly of dolerite that intruded into the Sydney Basin rocks during the Jurassic period (although most of the dolerite has been quarried away).
 * Prospect Reservoir in Prospect Nature Reserve, located within the Western Sydney Parklands, is a water storage reservoir located at the headwaters of Prospect Creek. Surrounding the Reservoir, there are recreational picnic areas, playgrounds, public parking and shelters.
 * St Bartholomew's Church of England is a brick church with a cemetery that contains the tomb of Lieutenant William Lawson and the graves of a number of pioneering families. It is listed on the Register of the National Estate.
 * Raging Waters Sydney, a large water park, is located in Prospect. It was opened on 12 December 2013, formerly known as Wet'n'Wild
 * Hylands Inn - Located at Hylands Road, in the 1880s, this later became the family home and dairy farm of Luke Hyland. Was a Cobb & Co stop. Horses were rested in the paddocks at the rear. The Coach travelled from Sydney to Hylands Inn for the overnight stop then on to Penrith then over the Blue Mountains.  Holroyd Youth Services lease building as a youth centre. This was one of five hotels operating during the construction of the Reservoir. Others were The Fox under the Hill, The Prospect Inn and Buckett’s Hotel.
 * Royal Cricketers Arms - Built in 1877, the hotel is one of the few remaining roadside inns that were on The Great Western Highway between Sydney and Bathurst, as well as being one of the last remaining buildings (along with the former village Post Office) of the Prospect Village. The Royal Cricketers Arms building is of Victorian and Georgian design, being a two-storey brick and timber building set on a random rubble foundation stone wall on a sloping site.

Transport
Prospect is adjacent to the Great Western Highway and the M4 Motorway, providing road access to the western sections of the city and eastward to the Sydney CBD.

The Prospect Highway links Prospect to central Blacktown.

Blacktown railway station provides access to the Sydney Trains and NSW TrainLink networks, especially Sydney Trains' North Shore & Western Line. Several bus companies offer connecting services between Prospect and Blacktown, via Blacktown Road.

Demographics
According to the 2011 census, the most common ancestries in Prospect were Australian 20.0%, English 16.1%, Maltese 6.2%, Irish 5.0% and Indian 4.6%.
 * Ancestry:

According to the 2016 census, the most common ancestries in Prospect were English 15.8%, Australian 15.7%, Indian 6.4%, Maltese 5.3% and Irish 4.8%.

62.0% of people were born in Australia. The other most common countries of birth were Fiji 3.0%, Philippines 2.8%, India 2.5%, Malta 2.3% and England 1.9%. 35.3% of people had both parents born in Australia and 53.1% of people had both parents born overseas.
 * Country of birth:

According to the 2016 census, 56.4% of people were born in Australia. The most common countries of birth were India 4.6%, Philippines 3.1%, Fiji 3.0%, Malta 2.1% and Sri Lanka 2.0%.

61.4% of people only spoke English at home. Other languages spoken at home included Arabic 4.7%, Hindi 4.1%, Greek 2.9%, Maltese 2.5% and Cantonese 1.8%.
 * Language:

The most common responses for religion in Prospect were Catholic 38.4%, Anglican 12.0%, No Religion 10.2%, Eastern Orthodox 5.7% and Hinduism 5.6%.
 * Religion:

Notable residents
Notable people who have resided in the suburb include:
 * Pemulwuy - a member of the Bidjigal tribe, was the main leader of raids by aboriginal people against the colony of New South Wales in the 1790s. In 1797 the war escalated; his guerrillas started regular raids on settlements in the Parramatta and Prospect Hill areas.
 * William Lawson - who with Gregory Blaxland and William Charles Wentworth, explored a route across the Blue Mountains. He was granted 500 acre at Prospect and built a large house there in the 1820s, which he named Veteran Hall.
 * Natasha Crofts - Australian Mother of the Year in 2007

title: Prospect, New South Wales


text:
FPN

FPN may mean:

 * Faculty of Political Science in Sarajevo (Bosnian: Fakultet političkih nauka u Sarajevu)
 * Faculty of Political Sciences, University of Belgrade (Serbian: Fakultet političkih nauka Univerziteta u Beogradu)
 * Family nurse practitioner in the United States
 * Feldpost number, used for transmission of mail to German military in WWII
 * Feminist Peace Network in the United States
 * Fixed penalty notice, in the UK, a notification of what is usually a minor fine for an alleged criminal offence

Science and technology

 * Federated portal network, a software architecture
 * Ferroportin, a protein
 * Filtered-popping network in computer science
 * Fixed-pattern noise in digital imaging

title: FPN


text:
Omar Kabbaj

Omar Kabbaj is advisor to King Mohammed VI of Morocco since 22 June 2006. He was the chairman of the African Development Bank from 26 August 1995 to 1 September 2005. Before that, he was a member of the board of the International Monetary Fund (1980–1993) and member of the board of directors of the World Bank (1979–1980) and minister delegate to the prime minister of Morocco, in charge of affairs economic, from 1993 to 1995. Omar Kabbaj is also a Knight of the Order of the Throne of Morocco. He holds a master's degree in management from Toulouse Business School.

title: Omar Kabbaj


text:
List of junior colleges in the United States

This is a list of junior colleges in the United States. Most of these institutions are private; public two-year community colleges are excluded.

California
east Los Angeles community college
 * California Preparatory College, Redlands
 * Deep Springs College, Deep Springs Valley
 * MTI College, Sacramento

Colorado

 * Colorado School of Trades, Lakewood

Connecticut

 * Lincoln College of New England, Southington

Georgia

 * Georgia Military College, Milledgeville
 * Oxford College, Oxford

Hawaii

 * Hawaii Tokai International College, Honolulu
 * TransPacific Hawaii College, Honolulu

Indiana

 * Ancilla College, Donaldson

Kansas

 * Hesston College, Hesston

Maine

 * Andover College, Portland

Massachusetts

 * Labouré College, Boston

Minnesota

 * Maranatha Bible School, Lansing

Mississippi

 * Mary Holmes College, West Point (defunct)
 * Mississippi Industrial College, Holly Springs (defunct)
 * Wood Junior College, Mathiston (defunct)

New Jersey

 * Assumption College for Sisters, Denville

New Mexico

 * New Mexico Junior College, Hobbs

New York

 * Trocaire College, Buffalo

North Carolina

 * Louisburg College, Louisburg

Ohio

 * Chatfield College, St. Martin
 * Rosedale Bible College, Rosedale

Pennsylvania

 * Harcum College, Bryn Mawr
 * Lackawanna College, Scranton
 * Pennsylvania Institute of Technology, Media and Philadelphia
 * Valley Forge Military Academy and College, Wayne
 * Williamson College of the Trades, Media

Tennessee

 * Hiwassee College, Madisonville

Texas

 * Jacksonville College, Jacksonville
 * Lon Morris College, Jacksonville
 * Odessa College, Odessa
 * Southwestern Christian College, Terrell
 * Tyler Junior College, Tyler*

Virginia

 * Richard Bland College of William and Mary, Petersburg

West Virginia

 * Huntington Junior College, Huntington
 * West Virginia Junior College, Bridgeport, Charleston and Morgantown


text:
Isotopes of chlorine

Chlorine (17Cl) has 25 isotopes, ranging from 28Cl to 52Cl, and two isomers, 34mCl and 38mCl. There are two stable isotopes, 35Cl (75.8%) and 37Cl (24.2%), giving chlorine a standard atomic weight of 35.45. The longest-lived radioactive isotope is 36Cl, which has a half-life of 301,000 years. All other isotopes have half-lives under 1 hour, many less than one second. The shortest-lived are proton-unbound 29Cl and 30Cl, with half-lives less than 10 picoseconds and 30 nanoseconds, respectively; the half-life of 28Cl is unknown.

List of isotopes

 * 28Cl
 * style="text-align:right" | 17
 * style="text-align:right" | 11
 * 28.03035(54)#
 * p
 * 27S
 * 1+#
 * 29Cl
 * style="text-align:right" | 17
 * style="text-align:right" | 12
 * 29.01505(20)#
 * 5.4(19) zs
 * p
 * 28S
 * (1/2+)
 * 30Cl
 * style="text-align:right" | 17
 * style="text-align:right" | 13
 * 30.005018(26)
 * <50 ns
 * p
 * 29S
 * 3+#
 * rowspan=2|31Cl
 * rowspan=2 style="text-align:right" | 17
 * rowspan=2 style="text-align:right" | 14
 * rowspan=2|30.9924481(37)
 * rowspan=2|190(1) ms
 * β+ (97.6%)
 * 31S
 * rowspan=2|3/2+
 * rowspan=2|
 * rowspan=2|
 * β+, p (2.4%)
 * 30P
 * rowspan=3|32Cl
 * rowspan=3 style="text-align:right" | 17
 * rowspan=3 style="text-align:right" | 15
 * rowspan=3|31.98568461(60)
 * rowspan=3|298(1) ms
 * β+ (99.92%)
 * 32S
 * rowspan=3|1+
 * rowspan=3|
 * rowspan=3|
 * β+, α (0.054%)
 * 28Si
 * β+, p (0.026%)
 * 31P
 * 33Cl
 * style="text-align:right" | 17
 * style="text-align:right" | 16
 * 32.97745199(42)
 * 2.5038(22) s
 * β+
 * 33S
 * 3/2+
 * 34Cl
 * style="text-align:right" | 17
 * style="text-align:right" | 17
 * 33.973762490(52)
 * 1.5267(4) s
 * β+
 * 34S
 * 0+
 * rowspan=2 style="text-indent:1em" | 34mCl
 * rowspan=2 colspan="3" style="text-indent:2em" | 146.360(27) keV
 * rowspan=2|31.99(3) min
 * β+ (55.4%)
 * 34S
 * rowspan=2|3+
 * rowspan=2|
 * rowspan=2|
 * IT (44.6%)
 * 34Cl
 * 35Cl
 * style="text-align:right" | 17
 * style="text-align:right" | 18
 * 34.968852694(38)
 * colspan=3 align=center|Stable
 * 3/2+
 * 0.758(2)
 * rowspan=2|36Cl
 * rowspan=2 style="text-align:right" | 17
 * rowspan=2 style="text-align:right" | 19
 * rowspan=2|35.968306822(38)
 * rowspan=2|3.013(15)×105 y
 * β− (98.1%)
 * 36Ar
 * rowspan=2|2+
 * rowspan=2|$0$
 * rowspan=2|
 * β+ (1.9%)
 * 36S
 * 37Cl
 * style="text-align:right" | 17
 * style="text-align:right" | 20
 * 36.965902573(55)
 * colspan=3 align=center|Stable
 * 3/2+
 * 0.242(2)
 * 38Cl
 * style="text-align:right" | 17
 * style="text-align:right" | 21
 * 37.96801041(11)
 * 37.230(14) min
 * β−
 * 38Ar
 * 2−
 * style="text-indent:1em" | 38mCl
 * colspan="3" style="text-indent:2em" | 671.365(8) keV
 * 715(3) ms
 * IT
 * 38Cl
 * 5−
 * 39Cl
 * style="text-align:right" | 17
 * style="text-align:right" | 22
 * 38.9680082(19)
 * 56.2(6) min
 * β−
 * 39Ar
 * 3/2+
 * 40Cl
 * style="text-align:right" | 17
 * style="text-align:right" | 23
 * 39.970415(34)
 * 1.35(3) min
 * β−
 * 40Ar
 * 2−
 * 41Cl
 * style="text-align:right" | 17
 * style="text-align:right" | 24
 * 40.970685(74)
 * 38.4(8) s
 * β−
 * 41Ar
 * (1/2+)
 * rowspan=2|42Cl
 * rowspan=2 style="text-align:right" | 17
 * rowspan=2 style="text-align:right" | 25
 * rowspan=2|41.973342(64)
 * rowspan=2|6.8(3) s
 * β−
 * 42Ar
 * rowspan=2|(2−)
 * rowspan=2|
 * rowspan=2|
 * β−, n?
 * 41Ar
 * rowspan=2|43Cl
 * rowspan=2 style="text-align:right" | 17
 * rowspan=2 style="text-align:right" | 26
 * rowspan=2|42.974064(66)
 * rowspan=2|3.13(9) s
 * β−
 * 43Ar
 * rowspan=2|(3/2+)
 * rowspan=2|
 * rowspan=2|
 * β−, n?
 * 42Ar
 * rowspan=2|44Cl
 * rowspan=2 style="text-align:right" | 17
 * rowspan=2 style="text-align:right" | 27
 * rowspan=2|43.978015(92)
 * rowspan=2|0.56(11) s
 * β− (>92%)
 * 44Ar
 * rowspan=2|(2-)
 * rowspan=2|
 * rowspan=2|
 * β−, n? (<8%)
 * 43Ar
 * rowspan=2|45Cl
 * rowspan=2 style="text-align:right" | 17
 * rowspan=2 style="text-align:right" | 28
 * rowspan=2|44.98039(15)
 * rowspan=2|513(36) ms
 * β− (76%)
 * 45Ar
 * rowspan=2|(3/2+)
 * rowspan=2|
 * rowspan=2|
 * β−, n (24%)
 * 44Ar
 * rowspan=3|46Cl
 * rowspan=3 style="text-align:right" | 17
 * rowspan=3 style="text-align:right" | 29
 * rowspan=3|45.98525(10)
 * rowspan=3|232(2) ms
 * β−, n (60%)
 * 45Ar
 * rowspan=3|2-#
 * rowspan=3|
 * rowspan=3|
 * β− (40%)
 * 46Ar
 * β−, 2n?
 * 44Ar
 * rowspan=3|47Cl
 * rowspan=3 style="text-align:right" | 17
 * rowspan=3 style="text-align:right" | 30
 * rowspan=3|46.98972(22)#
 * rowspan=3|101(5) ms
 * β− (>97%)
 * 47Ar
 * rowspan=3|3/2+#
 * rowspan=3|
 * rowspan=3|
 * β−, n? (<3%)
 * 46Ar
 * β−, 2n?
 * 45Ar
 * rowspan=3|48Cl
 * rowspan=3 style="text-align:right" | 17
 * rowspan=3 style="text-align:right" | 31
 * rowspan=3|47.99541(54)#
 * rowspan=3|30# ms [>200 ns]
 * β−?
 * 48Ar
 * rowspan=3|
 * rowspan=3|
 * rowspan=3|
 * β−, n?
 * 47Ar
 * β−, 2n?
 * 46Ar
 * rowspan=3|49Cl
 * rowspan=3 style="text-align:right" | 17
 * rowspan=3 style="text-align:right" | 32
 * rowspan=3|49.00079(43)#
 * rowspan=3|35# ms [>200 ns]
 * β−?
 * 49Ar
 * rowspan=3|3/2+#
 * rowspan=3|
 * rowspan=3|
 * β−, n?
 * 48Ar
 * β−, 2n?
 * 47Ar
 * rowspan=3|50Cl
 * rowspan=3 style="text-align:right" | 17
 * rowspan=3 style="text-align:right" | 33
 * rowspan=3|50.00827(43)#
 * rowspan=3|10# ms [>620 ns]
 * β−
 * 50Ar
 * rowspan=3|
 * rowspan=3|
 * rowspan=3|
 * β−, n?
 * 49Ar
 * β−, 2n?
 * 48Ar
 * rowspan=3|51Cl
 * rowspan=3 style="text-align:right" | 17
 * rowspan=3 style="text-align:right" | 34
 * rowspan=3|51.01534(75)#
 * rowspan=3|5# ms [>200 ns]
 * β−?
 * 51Ar
 * rowspan=3|3/2+#
 * rowspan=3|
 * rowspan=3|
 * β−, n?
 * 50Ar
 * β−, 2n?
 * 49Ar
 * rowspan=3|52Cl
 * rowspan=3 style="text-align:right" | 17
 * rowspan=3 style="text-align:right" | 35
 * rowspan=3|52.02400(75)#
 * rowspan=3|2# ms [>400 ns]
 * β−?
 * 52Ar
 * rowspan=3|
 * rowspan=3|
 * rowspan=3|
 * β−, n?
 * 51Ar
 * β−, 2n?
 * 50Ar
 * β−, n?
 * 47Ar
 * β−, 2n?
 * 46Ar
 * rowspan=3|49Cl
 * rowspan=3 style="text-align:right" | 17
 * rowspan=3 style="text-align:right" | 32
 * rowspan=3|49.00079(43)#
 * rowspan=3|35# ms [>200 ns]
 * β−?
 * 49Ar
 * rowspan=3|3/2+#
 * rowspan=3|
 * rowspan=3|
 * β−, n?
 * 48Ar
 * β−, 2n?
 * 47Ar
 * rowspan=3|50Cl
 * rowspan=3 style="text-align:right" | 17
 * rowspan=3 style="text-align:right" | 33
 * rowspan=3|50.00827(43)#
 * rowspan=3|10# ms [>620 ns]
 * β−
 * 50Ar
 * rowspan=3|
 * rowspan=3|
 * rowspan=3|
 * β−, n?
 * 49Ar
 * β−, 2n?
 * 48Ar
 * rowspan=3|51Cl
 * rowspan=3 style="text-align:right" | 17
 * rowspan=3 style="text-align:right" | 34
 * rowspan=3|51.01534(75)#
 * rowspan=3|5# ms [>200 ns]
 * β−?
 * 51Ar
 * rowspan=3|3/2+#
 * rowspan=3|
 * rowspan=3|
 * β−, n?
 * 50Ar
 * β−, 2n?
 * 49Ar
 * rowspan=3|52Cl
 * rowspan=3 style="text-align:right" | 17
 * rowspan=3 style="text-align:right" | 35
 * rowspan=3|52.02400(75)#
 * rowspan=3|2# ms [>400 ns]
 * β−?
 * 52Ar
 * rowspan=3|
 * rowspan=3|
 * rowspan=3|
 * β−, n?
 * 51Ar
 * β−, 2n?
 * 50Ar
 * rowspan=3|52.02400(75)#
 * rowspan=3|2# ms [>400 ns]
 * β−?
 * 52Ar
 * rowspan=3|
 * rowspan=3|
 * rowspan=3|
 * β−, n?
 * 51Ar
 * β−, 2n?
 * 50Ar
 * β−, 2n?
 * 50Ar

Chlorine-36
Trace amounts of radioactive 36Cl exist in the environment, in a ratio of about 7×10−13 to 1 with stable isotopes. 36Cl is produced in the atmosphere by spallation of 36Ar by interactions with cosmic ray protons. In the subsurface environment, 36Cl is generated primarily as a result of neutron capture by 35Cl or muon capture by 40Ca. 36Cl decays to either 36S (1.9%) or to 36Ar (98.1%), with a combined half-life of 308,000 years. The half-life of this hydrophilic nonreactive isotope makes it suitable for geologic dating in the range of 60,000 to 1 million years. Additionally, large amounts of 36Cl were produced by neutron irradiation of seawater during atmospheric detonations of nuclear weapons between 1952 and 1958. The residence time of 36Cl in the atmosphere is about 1 week. Thus, as an event marker of 1950s water in soil and ground water, 36Cl is also useful for dating waters less than 50 years before the present. 36Cl has seen use in other areas of the geological sciences, forecasts, and elements. In chloride-based molten salt reactors the production of by neutron capture is an inevitable consequence of using natural isotope mixtures of chlorine (i.e. Those containing ). This produces a long lived radioactive product which has to be stored or disposed off. Isotope separation to produce pure can vastly reduce  production, but a small amount might still be produced by (n,2n) reactions involving fast neutrons.

Chlorine-37
Stable chlorine-37 makes up about 24.23% of the naturally occurring chlorine on earth. Variation occurs as chloride mineral deposits have a slightly elevated chlorine-37 balance over the average found in sea water and halite deposits.

title: Isotopes of chlorine


text:
Isotopes of phosphorus

Although phosphorus (15P) has 22 isotopes from 26P to 47P, only 31P is stable; as such, phosphorus is considered a monoisotopic element. The longest-lived radioactive isotopes are 33P with a half-life of 25.34 days and 32P with a half-life of 14.268 days. All others have half-lives of under 2.5 minutes, most under a second. The least stable known isotope is 47P, with a half-life of 2 milliseconds.

List of isotopes

 * rowspan=2|26P
 * rowspan=2 style="text-align:right" | 15
 * rowspan=2 style="text-align:right" | 11
 * rowspan=2|26.01178(21)#
 * rowspan=2|43.7(6) ms
 * β+ (63.2%)
 * 26Si
 * rowspan=2|(3+)
 * rowspan=2|
 * β+, p (36.8%)
 * 25Al
 * style="text-indent:1em"|26mP
 * colspan=3 style="text-indent:2em"|164.4(1) keV
 * 120(9) ns
 * IT
 * 26P
 * rowspan=2|27P
 * rowspan=2 style="text-align:right" | 15
 * rowspan=2 style="text-align:right" | 12
 * rowspan=2|26.999224(28)
 * rowspan=2|260(80) ms
 * β+ (99.93%)
 * 27Si
 * rowspan=2|1/2+
 * rowspan=2|
 * β+, p (.07%)
 * 26Al
 * rowspan=3|28P
 * rowspan=3 style="text-align:right" | 15
 * rowspan=3 style="text-align:right" | 13
 * rowspan=3|27.9923266(12)
 * rowspan=3|270.3(5) ms
 * β+ (99.99%)
 * 28Si
 * rowspan=3|3+
 * rowspan=3|
 * β+, p (.0013%)
 * 27Al
 * β+, α (8.6×10−4%)
 * 24Mg
 * 29P
 * style="text-align:right" | 15
 * style="text-align:right" | 14
 * 28.9818004(4)
 * 4.142(15) s
 * β+
 * 29Si
 * 1/2+
 * 30P
 * style="text-align:right" | 15
 * style="text-align:right" | 15
 * 29.97831349(7)
 * 2.498(4) min
 * β+
 * 30Si
 * 1+
 * 31P
 * style="text-align:right" | 15
 * style="text-align:right" | 16
 * 30.9737619986(7)
 * colspan=3 align=center|Stable
 * 1/2+
 * 1.0000
 * 32P
 * style="text-align:right" | 15
 * style="text-align:right" | 17
 * 31.97390764(4)
 * 14.268(5) d
 * β−
 * 32S
 * 1+
 * Trace
 * 33P
 * style="text-align:right" | 15
 * style="text-align:right" | 18
 * 32.9717257(12)
 * 25.35(11) d
 * β−
 * 33S
 * 1/2+
 * 34P
 * style="text-align:right" | 15
 * style="text-align:right" | 19
 * 33.9736459(9)
 * 12.43(10) s
 * β−
 * 34S
 * 1+
 * 35P
 * style="text-align:right" | 15
 * style="text-align:right" | 20
 * 34.9733141(20)
 * 47.3(8) s
 * β−
 * 35S
 * 1/2+
 * 36P
 * style="text-align:right" | 15
 * style="text-align:right" | 21
 * 35.978260(14)
 * 5.6(3) s
 * β−
 * 36S
 * 4−
 * 37P
 * style="text-align:right" | 15
 * style="text-align:right" | 22
 * 36.97961(4)
 * 2.31(13) s
 * β−
 * 37S
 * (1/2+)
 * rowspan=2|38P
 * rowspan=2 style="text-align:right" | 15
 * rowspan=2 style="text-align:right" | 23
 * rowspan=2|37.98430(8)
 * rowspan=2|0.64(14) s
 * β− (87.5%)
 * 38S
 * rowspan=2|
 * rowspan=2|
 * β−, n (12.5%)
 * 37S
 * rowspan=2|39P
 * rowspan=2 style="text-align:right" | 15
 * rowspan=2 style="text-align:right" | 24
 * rowspan=2|38.98629(12)
 * rowspan=2|282(24) ms
 * β− (73.2%)
 * 39S
 * rowspan=2|1/2+#
 * rowspan=2|
 * β−, n (26.8%)
 * 38S
 * rowspan=2|40P
 * rowspan=2 style="text-align:right" | 15
 * rowspan=2 style="text-align:right" | 25
 * rowspan=2|39.99129(16)
 * rowspan=2|150(8) ms
 * β− (84.2%)
 * 40S
 * rowspan=2|(2−,3−)
 * rowspan=2|
 * β−, n (15.8%)
 * 39S
 * rowspan=2|41P
 * rowspan=2 style="text-align:right" | 15
 * rowspan=2 style="text-align:right" | 26
 * rowspan=2|40.99465(13)
 * rowspan=2|101(5) ms
 * β− (70%)
 * 41S
 * rowspan=2|1/2+#
 * rowspan=2|
 * β−, n (30%)
 * 40S
 * rowspan=2|42P
 * rowspan=2 style="text-align:right" | 15
 * rowspan=2 style="text-align:right" | 27
 * rowspan=2|42.00108(34)
 * rowspan=2|48.5(15) ms
 * β− (50%)
 * 42S
 * rowspan=2|
 * rowspan=2|
 * β−, n (50%)
 * 41S
 * rowspan=2|43P
 * rowspan=2 style="text-align:right" | 15
 * rowspan=2 style="text-align:right" | 28
 * rowspan=2|43.00502(60)
 * rowspan=2|35.8(13) ms
 * β−, n (100%)
 * 42S
 * rowspan=2|1/2+#
 * rowspan=2|
 * β−, 2n ?
 * 41S
 * 44P
 * style="text-align:right" | 15
 * style="text-align:right" | 29
 * 44.01122(54)#
 * 18.5(25) ms
 * β−
 * 44S
 * rowspan=2|45P
 * rowspan=2 style="text-align:right" | 15
 * rowspan=2 style="text-align:right" | 30
 * rowspan=2|45.01675(54)#
 * rowspan=2|24(7 (stat), 9 (sys)) ms
 * β−, n (79%)
 * 44S
 * rowspan=2|1/2+#
 * rowspan=2|
 * β−, 2n (21%)
 * 43S
 * 46P
 * style="text-align:right" | 15
 * style="text-align:right" | 31
 * 46.02466(75)#
 * 4# ms [>200 ns]
 * β−
 * 46S
 * 47P
 * style="text-align:right" | 15
 * style="text-align:right" | 32
 * 47.03190(86)#
 * 2# ms
 * β−
 * 47S
 * 42S
 * rowspan=2|1/2+#
 * rowspan=2|
 * β−, 2n ?
 * 41S
 * 44P
 * style="text-align:right" | 15
 * style="text-align:right" | 29
 * 44.01122(54)#
 * 18.5(25) ms
 * β−
 * 44S
 * rowspan=2|45P
 * rowspan=2 style="text-align:right" | 15
 * rowspan=2 style="text-align:right" | 30
 * rowspan=2|45.01675(54)#
 * rowspan=2|24(7 (stat), 9 (sys)) ms
 * β−, n (79%)
 * 44S
 * rowspan=2|1/2+#
 * rowspan=2|
 * β−, 2n (21%)
 * 43S
 * 46P
 * style="text-align:right" | 15
 * style="text-align:right" | 31
 * 46.02466(75)#
 * 4# ms [>200 ns]
 * β−
 * 46S
 * 47P
 * style="text-align:right" | 15
 * style="text-align:right" | 32
 * 47.03190(86)#
 * 2# ms
 * β−
 * 47S
 * 47P
 * style="text-align:right" | 15
 * style="text-align:right" | 32
 * 47.03190(86)#
 * 2# ms
 * β−
 * 47S
 * 2# ms
 * β−
 * 47S

Phosphorus-32
32P is a radioactive isotope of phosphorus with relative atomic mass 31.973907 and half-life of 14.26 days. 32P is a radioactive isotope of phosphorus with beta particle-emitting radiocytotoxic activity. Emitted by 32P, beta particles directly damage cellular DNA and, by ionizing intracellular water to produce several types of cytotoxic free radicals and superoxides, indirectly damage intracellular biological macromolecules, resulting in tumor cell death.

Phosphorus-33
33P is an artificial radioactive element. It is produced with a low yield by the neutron bombardment of 31P (stable). The 33P has a radioactive period of 25.3 days. It is a pure β-transmitter. 33P is used as an alternative to 32P in research in molecular biology. Indeed, its longer life time and especially its less energetic β spectrum make its manipulation simpler in the laboratory. In the medical field, 33P has been used in the treatment of arterial stenosis but is no longer indicated at this time.

title: Isotopes of phosphorus


text:
Isotopes of silicon

Silicon (14Si) has 23 known isotopes, with mass numbers ranging from 22 to 44. 28Si (the most abundant isotope, at 92.23%), 29Si (4.67%), and 30Si (3.1%) are stable. The longest-lived radioisotope is 32Si, which is produced by cosmic ray spallation of argon. Its half-life has been determined to be approximately 150 years (with decay energy 0.21 MeV), and it decays by beta emission to 32P (which has a 14.27-day half-life) and then to 32S. After 32Si, 31Si has the second longest half-life at 157.3 minutes. All others have half-lives under 7 seconds.

List of isotopes

 * rowspan=3|22Si
 * rowspan=3 style="text-align:right" | 14
 * rowspan=3 style="text-align:right" | 8
 * rowspan=3|22.03611(54)#
 * rowspan=3|28.7(11) ms
 * β+, p (62%)
 * 21Mg
 * rowspan=3|0+
 * rowspan=3|
 * rowspan=3|
 * β+ (37%)
 * 22Al
 * β+, 2p (0.7%)
 * 20Na
 * rowspan=3|23Si
 * rowspan=3 style="text-align:right" | 14
 * rowspan=3 style="text-align:right" | 9
 * rowspan=3|23.02571(54)#
 * rowspan=3|42.3(4) ms
 * β+, p (88%)
 * 22Mg
 * rowspan=3|3/2+#
 * rowspan=3|
 * rowspan=3|
 * β+ (8%)
 * 23Al
 * β+, 2p (3.6%)
 * 21Na
 * rowspan=2|24Si
 * rowspan=2 style="text-align:right" | 14
 * rowspan=2 style="text-align:right" | 10
 * rowspan=2|24.011535(21)
 * rowspan=2|143.2 (21) ms
 * β+ (65.5%)
 * 24Al
 * rowspan=2|0+
 * rowspan=2|
 * rowspan=2|
 * β+, p (34.5%)
 * 23Mg
 * rowspan=2|25Si
 * rowspan=2 style="text-align:right" | 14
 * rowspan=2 style="text-align:right" | 11
 * rowspan=2|25.004109(11)
 * rowspan=2|220.6(10) ms
 * β+ (65%)
 * 25Al
 * rowspan=2|5/2+
 * rowspan=2|
 * rowspan=2|
 * β+, p (35%)
 * 24Mg
 * 26Si
 * style="text-align:right" | 14
 * style="text-align:right" | 12
 * 25.99233382(12)
 * 2.2453(7) s
 * β+
 * 26Al
 * 0+
 * 27Si
 * style="text-align:right" | 14
 * style="text-align:right" | 13
 * 26.98670469(12)
 * 4.117(14) s
 * β+
 * 27Al
 * 5/2+
 * 28Si
 * style="text-align:right" | 14
 * style="text-align:right" | 14
 * 27.97692653442(55)
 * colspan=3 align=center|Stable
 * 0+
 * 0.92223(19)
 * 0.92205–0.92241
 * 29Si
 * style="text-align:right" | 14
 * style="text-align:right" | 15
 * 28.97649466434(60)
 * colspan=3 align=center|Stable
 * 1/2+
 * 0.04685(8)
 * 0.04678–0.04692
 * 30Si
 * style="text-align:right" | 14
 * style="text-align:right" | 16
 * 29.973770137(23)
 * colspan=3 align=center|Stable
 * 0+
 * 0.03092(11)
 * 0.03082–0.03102
 * 31Si
 * style="text-align:right" | 14
 * style="text-align:right" | 17
 * 30.975363196(46)
 * 157.16(20) min
 * β−
 * 31P
 * 3/2+
 * 32Si
 * style="text-align:right" | 14
 * style="text-align:right" | 18
 * 31.97415154(32)
 * 157(7) y
 * β−
 * 32P
 * 0+
 * trace
 * cosmogenic
 * 33Si
 * style="text-align:right" | 14
 * style="text-align:right" | 19
 * 32.97797696(75)
 * 6.18(18) s
 * β−
 * 33P
 * 3/2+
 * 34Si
 * style="text-align:right" | 14
 * style="text-align:right" | 20
 * 33.97853805(86)
 * 2.77(20) s
 * β−
 * 34P
 * 0+
 * style="text-indent:1em" |34mSi
 * colspan=3 style="text-indent:2em" | 4256.1(4) keV
 * <210 ns
 * IT
 * 34Si
 * (3−)
 * rowspan=2|35Si
 * rowspan=2 style="text-align:right" | 14
 * rowspan=2 style="text-align:right" | 21
 * rowspan=2|34.984550(38)
 * rowspan=2|780(120) ms
 * β−
 * 35P
 * rowspan=2|7/2−#
 * rowspan=2|
 * rowspan=2|
 * β−, n?
 * 34P
 * rowspan=2|36Si
 * rowspan=2 style="text-align:right" | 14
 * rowspan=2 style="text-align:right" | 22
 * rowspan=2|35.986649(77)
 * rowspan=2|503(2) ms
 * β− (88%)
 * 36P
 * rowspan=2|0+
 * rowspan=2|
 * rowspan=2|
 * β−, n (12%)
 * 35P
 * rowspan=3|37Si
 * rowspan=3 style="text-align:right" | 14
 * rowspan=3 style="text-align:right" | 23
 * rowspan=3|36.99295(12)
 * rowspan=3|141.0(35) ms
 * β− (83%)
 * 37P
 * rowspan=3|(5/2−)
 * rowspan=3|
 * rowspan=3|
 * β−, n (17%)
 * 36P
 * β−, 2n?
 * 35P
 * rowspan=2|38Si
 * rowspan=2 style="text-align:right" | 14
 * rowspan=2 style="text-align:right" | 24
 * rowspan=2|37.99552(11)
 * rowspan=2|63(8) ms
 * β− (75%)
 * 38P
 * rowspan=2|0+
 * rowspan=2|
 * rowspan=2|
 * β−, n (25%)
 * 37P
 * rowspan=3|39Si
 * rowspan=3 style="text-align:right" | 14
 * rowspan=3 style="text-align:right" | 25
 * rowspan=3|39.00249(15)
 * rowspan=3|41.2(41) ms
 * β− (67%)
 * 39P
 * rowspan=3|(5/2−)
 * rowspan=3|
 * rowspan=3|
 * β−, n (33%)
 * 38P
 * β−, 2n?
 * 37P
 * rowspan=3|40Si
 * rowspan=3 style="text-align:right" | 14
 * rowspan=3 style="text-align:right" | 26
 * rowspan=3|40.00608(13)
 * rowspan=3|31.2(26) ms
 * β− (62%)
 * 40P
 * rowspan=3|0+
 * rowspan=3|
 * rowspan=3|
 * β−, n (38%)
 * 39P
 * β−, 2n?
 * 38P
 * rowspan=3|41Si
 * rowspan=3 style="text-align:right" | 14
 * rowspan=3 style="text-align:right" | 27
 * rowspan=3|41.01417(32)#
 * rowspan=3|20.0(25) ms
 * β−, n (>55%)
 * 40P
 * rowspan=3|7/2−#
 * rowspan=3|
 * rowspan=3|
 * β− (<45%)
 * 41P
 * β−, 2n?
 * 39P
 * rowspan=3|42Si
 * rowspan=3 style="text-align:right" | 14
 * rowspan=3 style="text-align:right" | 28
 * rowspan=3|42.01808(32)#
 * rowspan=3|15.5(4 (stat), 16 (sys)) ms
 * β− (51%)
 * 42P
 * rowspan=3|0+
 * rowspan=3|
 * rowspan=3|
 * β−, n (48%)
 * 41P
 * β−, 2n (1%)
 * 40P
 * rowspan=3|43Si
 * rowspan=3 style="text-align:right" | 14
 * rowspan=3 style="text-align:right" | 29
 * rowspan=3|43.02612(43)#
 * rowspan=3|13(4 (stat), 2 (sys)) ms
 * β−, n (52%)
 * 42P
 * rowspan=3|3/2−#
 * rowspan=3|
 * rowspan=3|
 * β− (27%)
 * 43P
 * β−, 2n (21%)
 * 41P
 * rowspan=3|44Si
 * rowspan=3 style="text-align:right" | 14
 * rowspan=3 style="text-align:right" | 30
 * rowspan=3|44.03147(54)#
 * rowspan=3|4# ms [>360 ns]
 * β−?
 * 44P
 * rowspan=3|0+
 * rowspan=3|
 * rowspan=3|
 * β−, n?
 * 43P
 * β−, 2n?
 * 42P
 * rowspan=3|
 * rowspan=3|
 * β− (<45%)
 * 41P
 * β−, 2n?
 * 39P
 * rowspan=3|42Si
 * rowspan=3 style="text-align:right" | 14
 * rowspan=3 style="text-align:right" | 28
 * rowspan=3|42.01808(32)#
 * rowspan=3|15.5(4 (stat), 16 (sys)) ms
 * β− (51%)
 * 42P
 * rowspan=3|0+
 * rowspan=3|
 * rowspan=3|
 * β−, n (48%)
 * 41P
 * β−, 2n (1%)
 * 40P
 * rowspan=3|43Si
 * rowspan=3 style="text-align:right" | 14
 * rowspan=3 style="text-align:right" | 29
 * rowspan=3|43.02612(43)#
 * rowspan=3|13(4 (stat), 2 (sys)) ms
 * β−, n (52%)
 * 42P
 * rowspan=3|3/2−#
 * rowspan=3|
 * rowspan=3|
 * β− (27%)
 * 43P
 * β−, 2n (21%)
 * 41P
 * rowspan=3|44Si
 * rowspan=3 style="text-align:right" | 14
 * rowspan=3 style="text-align:right" | 30
 * rowspan=3|44.03147(54)#
 * rowspan=3|4# ms [>360 ns]
 * β−?
 * 44P
 * rowspan=3|0+
 * rowspan=3|
 * rowspan=3|
 * β−, n?
 * 43P
 * β−, 2n?
 * 42P
 * β−?
 * 44P
 * rowspan=3|0+
 * rowspan=3|
 * rowspan=3|
 * β−, n?
 * 43P
 * β−, 2n?
 * 42P
 * β−, 2n?
 * 42P

Silicon-28
Silicon-28, the most abundant isotope of silicon, is of particular interest in the construction of quantum computers when highly enriched, as the presence of 29Si in a sample of silicon contributes to quantum decoherence. Extremely pure (>99.9998%) samples of 28Si can be produced through selective ionization and deposition of 28Si from silane gas. Due to the extremely high purity that can be obtained in this manner, the Avogadro project sought to develop a new definition of the kilogram by making a 93.75 mm sphere of the isotope and determing the exact number of atoms in the sample.

Silicon-28 is produced in stars during the alpha process and the oxygen-burning process, and drives the silicon-burning process in massive stars shortly before they go supernova.

Silicon-29
Silicon-29 is of note as the only stable silicon isotope with a nuclear spin (I = 1/2). As such, it can be employed in nuclear magnetic resonance and hyperfine transition studies, for example to study the properties of the so-called A-center defect in pure silicon.

Silicon-34
Silicon-34 is a radioactive isotope wth a half-life of 2.8 seconds. In addition to the usual N = 20 closed shell, the nucleus also shows a strong Z = 14 shell closure, making it behave like a doubly magic spherical nucleus, except that it is also located two protons above an island of inversion. Silicon-34 has an unusual "bubble" structure where the proton distribution is less dense at the center than near the surface, as the 2s1/2 proton orbital is almost unoccupied in the ground state, unlike in 36S where it is almost full. Silicon-34 is one of the known cluster decay emission particles; it is produced in the decay of 242Cm with a branching ratio of approximately $0$.

title: Isotopes of silicon