View source for Physics:Isotopes of californium

{{Short description|Nuclides with atomic number of 98 but with different mass numbers}}
{{Infobox californium isotopes}}
[[Chemistry:Californium|Californium]] (<sub>98</sub>Cf) is an artificial element, and thus a [[Physics:Standard atomic weight|standard atomic weight]] cannot be given. Like all artificial elements, it has no [[Physics:Stable isotope|stable isotope]]s. The first [[Physics:Isotope|isotope]] to be synthesized was <sup>245</sup>Cf in 1950. There are 20 known radioisotopes ranging from <sup>237</sup>Cf to <sup>256</sup>Cf and one [[Physics:Nuclear isomer|nuclear isomer]], <sup>249m</sup>Cf. The longest-lived isotope is <sup>251</sup>Cf with a [[Physics:Half-life|half-life]] of 898 years.

== List of isotopes ==
[[File:Cf-249.png|Cf-249|right|150px|thumb]]
[[File:Cf-251.png|Cf-251|right|150px|thumb]]
{{Isotopes table
|symbol=Cf
|refs=<!-- not NUBASE2016 yet (2019-07-14); see also Isobox for refs -->
|notes=m, unc(), mass#, spin(), spin#, SF, EC
}}
|-
| rowspan=3|<sup>237</sup>Cf<ref>{{cite journal |last1=Khuyagbaatar |first1=J. |last2=Heßberger |first2=F. P. |last3=Hofmann |first3=S. |last4=Ackermann |first4=D. |last5=Comas |first5=V. S. |last6=Heinz |first6=S. |last7=Heredia |first7=J. A. |last8=Kindler |first8=B. |last9=Kojouharov |first9=I. |last10=Lommel |first10=B. |last11=Mann |first11=R. |last12=Nishio |first12=K. |last13=Yakushev |first13=A. |title=The new isotope 236Cm and new data on 233Cm and 237, 238, 240Cf |journal=The European Physical Journal A |date=1 October 2010 |volume=46 |issue=1 |pages=59–67 |doi=10.1140/epja/i2010-11026-9 |bibcode=2010EPJA...46...59K |s2cid=122809010 |url=https://link.springer.com/content/pdf/10.1140/epja/i2010-11026-9.pdf |access-date=23 June 2023 |language=en |issn=1434-601X}}</ref>
| rowspan=3 style="text-align:right" | 98
| rowspan=3 style="text-align:right" | 139
| rowspan=3|237.06207(54)#
| rowspan=3|0.8(2)&nbsp;s
| [[Physics:Alpha decay|α]] (70%)
| <sup>233</sup>Cm
| rowspan=3|5/2+#
|-
| [[Physics:Spontaneous fission|SF]] (30%)
| (various)
|-
| [[Physics:Beta decay|β<sup>+</sup>]] (rare)
| <sup>237</sup>Bk
|-
| rowspan=2|<sup>238</sup>Cf
| rowspan=2 style="text-align:right" | 98
| rowspan=2 style="text-align:right" | 140
| rowspan=2|238.06141(43)#
| rowspan=2|21.1(13)&nbsp;ms
| SF<ref group="n">Lightest nuclide known to undergo [[Physics:Spontaneous fission|spontaneous fission]] as the main decay mode</ref>
| (various)
| rowspan=2|0+
|-
| α (<5%)<ref>{{cite journal |last1=Khuyagbaatar |first1=J. |last2=Heßberger |first2=F. P. |last3=Hofmann |first3=S. |last4=Ackermann |first4=D. |last5=Comas |first5=V. S. |last6=Heinz |first6=S. |last7=Heredia |first7=J. A. |last8=Kindler |first8=B. |last9=Kojouharov |first9=I. |last10=Lommel |first10=B. |last11=Mann |first11=R. |last12=Nishio |first12=K. |last13=Yakushev |first13=A. |title=The new isotope 236Cm and new data on 233Cm and 237, 238, 240Cf |journal=The European Physical Journal A |date=1 October 2010 |volume=46 |issue=1 |pages=59–67 |doi=10.1140/epja/i2010-11026-9 |bibcode=2010EPJA...46...59K |s2cid=122809010 |url=https://link.springer.com/content/pdf/10.1140/epja/i2010-11026-9.pdf |access-date=23 June 2023 |language=en |issn=1434-601X}}</ref>
| <sup>234</sup>Cm
|-
| rowspan=2|<sup>239</sup>Cf<ref>{{cite journal |last1=Khuyagbaatar |first1=J. |last2=Heßberger |first2=F. P. |last3=Hofmann |first3=S. |last4=Ackermann |first4=D. |last5=Burkhard |first5=H. G. |last6=Heinz |first6=S. |last7=Kindler |first7=B. |last8=Kojouharov |first8=I. |last9=Lommel |first9=B. |last10=Mann |first10=R. |last11=Maurer |first11=J. |last12=Nishio |first12=K. |title=α decay of Fm 243 143 and Fm 245 145 , and of their daughter nuclei |journal=Physical Review C |date=12 October 2020 |volume=102 |issue=4 |page=044312 |doi=10.1103/PhysRevC.102.044312 |s2cid=241259726 |url=https://journals.aps.org/prc/pdf/10.1103/PhysRevC.102.044312 |access-date=24 June 2023 |language=en |issn=2469-9985}}</ref>
| rowspan=2 style="text-align:right" | 98
| rowspan=2 style="text-align:right" | 141
| rowspan=2|239.06242(23)#
| rowspan=2|28(2)&nbsp;s
| α (65%)
| <sup>235</sup>Cm
| rowspan=2|(5/2+)
|-
| β<sup>+</sup> (35%)
| <sup>239</sup>Bk
|-
| rowspan=3|<sup>240</sup>Cf<ref>{{cite journal |last1=Kondev |first1=F. G. |last2=Wang |first2=M. |last3=Huang |first3=W. J. |last4=Naimi |first4=S. |last5=Audi |first5=G. |title=The NUBASE2020 evaluation of nuclear physics properties * |journal=Chinese Physics C, High Energy Physics and Nuclear Physics |date=1 March 2021 |volume=45 |issue=3 |page=030001 |doi=10.1088/1674-1137/abddae |bibcode=2021ChPhC..45c0001K |osti=1774641 |s2cid=233794940 |language=English |issn=1674-1137|doi-access=free }}</ref>
| rowspan=3 style="text-align:right" | 98
| rowspan=3 style="text-align:right" | 142
| rowspan=3|240.06230(22)#
| rowspan=3|40.3(9)&nbsp;s
| α (98.5%)
| <sup>236</sup>Cm
| rowspan=3|0+
|-
| SF (1.5%)
| (various)
|-
| β<sup>+</sup>?
| <sup>240</sup>Bk
|-
| rowspan=2|<sup>241</sup>Cf<ref>{{cite journal |last1=Kondev |first1=F. G. |last2=Wang |first2=M. |last3=Huang |first3=W. J. |last4=Naimi |first4=S. |last5=Audi |first5=G. |title=The NUBASE2020 evaluation of nuclear physics properties * |journal=Chinese Physics C, High Energy Physics and Nuclear Physics |date=1 March 2021 |volume=45 |issue=3 |page=030001 |doi=10.1088/1674-1137/abddae |bibcode=2021ChPhC..45c0001K |osti=1774641 |s2cid=233794940 |language=English |issn=1674-1137|doi-access=free }}</ref>
| rowspan=2 style="text-align:right" | 98
| rowspan=2 style="text-align:right" | 143
| rowspan=2|241.06373(27)#
| rowspan=2|2.35(18)&nbsp;min
| β<sup>+</sup> (85%)
| <sup>241</sup>Bk
| rowspan=2|(7/2−)
|-
| α (15%)
| <sup>237</sup>Cm
|-
| rowspan=3|<sup>242</sup>Cf<ref>{{cite journal |last1=Kondev |first1=F. G. |last2=Wang |first2=M. |last3=Huang |first3=W. J. |last4=Naimi |first4=S. |last5=Audi |first5=G. |title=The NUBASE2020 evaluation of nuclear physics properties * |journal=Chinese Physics C, High Energy Physics and Nuclear Physics |date=1 March 2021 |volume=45 |issue=3 |page=030001 |doi=10.1088/1674-1137/abddae |bibcode=2021ChPhC..45c0001K |osti=1774641 |s2cid=233794940 |language=English |issn=1674-1137|doi-access=free }}</ref>
| rowspan=3 style="text-align:right" | 98
| rowspan=3 style="text-align:right" | 144
| rowspan=3|242.06370(4)
| rowspan=3|3.49(15)&nbsp;min
| α (61%)
| <sup>238</sup>Cm
| rowspan=3|0+
|-
| β<sup>+</sup> (39%)
| <sup>242</sup>Bk
|-
| SF (<0.014%)
| (various)
|-
| rowspan=2|<sup>243</sup>Cf<ref>{{cite journal |last1=Kondev |first1=F. G. |last2=Wang |first2=M. |last3=Huang |first3=W. J. |last4=Naimi |first4=S. |last5=Audi |first5=G. |title=The NUBASE2020 evaluation of nuclear physics properties * |journal=Chinese Physics C, High Energy Physics and Nuclear Physics |date=1 March 2021 |volume=45 |issue=3 |page=030001 |doi=10.1088/1674-1137/abddae |bibcode=2021ChPhC..45c0001K |osti=1774641 |s2cid=233794940 |language=English |issn=1674-1137|doi-access=free }}</ref>
| rowspan=2 style="text-align:right" | 98
| rowspan=2 style="text-align:right" | 145
| rowspan=2|243.06543(15)#
| rowspan=2|10.8(3)&nbsp;min
| β<sup>+</sup> (86%)
| <sup>243</sup>Bk
| rowspan=2|(1/2+)
|-
| α (14%)
| <sup>239</sup>Cm
|-
| rowspan=2|<sup>244</sup>Cf<ref>{{cite journal |last1=Kondev |first1=F. G. |last2=Wang |first2=M. |last3=Huang |first3=W. J. |last4=Naimi |first4=S. |last5=Audi |first5=G. |title=The NUBASE2020 evaluation of nuclear physics properties * |journal=Chinese Physics C, High Energy Physics and Nuclear Physics |date=1 March 2021 |volume=45 |issue=3 |page=030001 |doi=10.1088/1674-1137/abddae |bibcode=2021ChPhC..45c0001K |osti=1774641 |s2cid=233794940 |language=English |issn=1674-1137|doi-access=free }}</ref>
| rowspan=2 style="text-align:right" | 98
| rowspan=2 style="text-align:right" | 146
| rowspan=2|244.066001(3)
| rowspan=2|19.5(5)&nbsp;min
| α (75%)
| <sup>240</sup>Cm
| rowspan=2|0+
|-
| [[Physics:Electron capture|EC]] (25%)
| <sup>244</sup>Bk
|-
| rowspan=2|<sup>245</sup>Cf<ref>{{cite journal |last1=Kondev |first1=F. G. |last2=Wang |first2=M. |last3=Huang |first3=W. J. |last4=Naimi |first4=S. |last5=Audi |first5=G. |title=The NUBASE2020 evaluation of nuclear physics properties * |journal=Chinese Physics C, High Energy Physics and Nuclear Physics |date=1 March 2021 |volume=45 |issue=3 |page=030001 |doi=10.1088/1674-1137/abddae |bibcode=2021ChPhC..45c0001K |osti=1774641 |s2cid=233794940 |language=English |issn=1674-1137|doi-access=free }}</ref>
| rowspan=2 style="text-align:right" | 98
| rowspan=2 style="text-align:right" | 147
| rowspan=2|245.068049(3)
| rowspan=2|45.0(15)&nbsp;min
| β<sup>+</sup> (64.7%)
| <sup>245</sup>Bk
| rowspan=2|1/2+
|-
| α (35.3%)
| <sup>241</sup>Cm
|-
| style="text-indent:1em" | <sup>245m</sup>Cf
| colspan="3" style="text-indent:2em" | 57(4)&nbsp;keV
| >100#&nbsp;ns
| IT
| <sup>245</sup>Cf
| (7/2+)
|-
| rowspan=3|<sup>246</sup>Cf
| rowspan=3 style="text-align:right" | 98
| rowspan=3 style="text-align:right" | 148
| rowspan=3|246.0688053(22)
| rowspan=3|35.7(5)&nbsp;h
| α
| <sup>242</sup>Cm
| rowspan=3|0+
|-
| EC (5×10<sup>−4</sup>%)
| <sup>246</sup>Bk
|-
| SF (2×10<sup>−4</sup>%)
| (various)
|-
| rowspan=2|<sup>247</sup>Cf
| rowspan=2 style="text-align:right" | 98
| rowspan=2 style="text-align:right" | 149
| rowspan=2|247.071001(9)
| rowspan=2|3.11(3)&nbsp;h
| EC (99.96%)
| <sup>247</sup>Bk
| rowspan=2|(7/2+)#
|-
| α (.04%)
| <sup>243</sup>Cm
|-
| rowspan=2|<sup>248</sup>Cf
| rowspan=2 style="text-align:right" | 98
| rowspan=2 style="text-align:right" | 150
| rowspan=2|248.072185(6)
| rowspan=2|333.5(28)&nbsp;d
| α (99.99%)
| <sup>244</sup>Cm
| rowspan=2|0+
|-
| SF (.0029%)
| (various)
|-
| rowspan=2|<sup>249</sup>Cf
| rowspan=2 style="text-align:right" | 98
| rowspan=2 style="text-align:right" | 151
| rowspan=2|249.0748535(24)
| rowspan=2|351(2)&nbsp;y
| α
| <sup>245</sup>Cm
| rowspan=2|9/2−
|-
| SF (5×10<sup>−7</sup>%)
| (various)
|-
| style="text-indent:1em" | <sup>249m</sup>Cf
| colspan="3" style="text-indent:2em" | 144.98(5)&nbsp;keV
| 45(5)&nbsp;μs
|
|
| 5/2+
|-
| rowspan=2|<sup>250</sup>Cf
| rowspan=2 style="text-align:right" | 98
| rowspan=2 style="text-align:right" | 152
| rowspan=2|250.0764061(22)
| rowspan=2|13.08(9)&nbsp;y
| α (99.92%)
| <sup>246</sup>Cm
| rowspan=2|0+
|-
| SF (.077%)
| (various)
|-
| <sup>251</sup>Cf<ref group="n">High neutron cross-section, tends to absorb neutrons</ref>
| style="text-align:right" | 98
| style="text-align:right" | 153
| 251.079587(5)
| 900(40)&nbsp;y
| α
| <sup>247</sup>Cm
| 1/2+
|-
| rowspan=2|<sup>252</sup>Cf<ref group="n">Most common isotope</ref>
| rowspan=2 style="text-align:right" | 98
| rowspan=2 style="text-align:right" | 154
| rowspan=2|252.081626(5)
| rowspan=2|2.645(8)&nbsp;y
| α (96.9%)
| <sup>248</sup>Cm
| rowspan=2|0+
|-
| SF (3.09%)<ref group="n">High neutron emitter, average 3.7 [[Physics:Neutron|neutron]]s per [[Physics:Nuclear fission|fission]]</ref>
| (various)
|-
| rowspan=2|<sup>253</sup>Cf
| rowspan=2 style="text-align:right" | 98
| rowspan=2 style="text-align:right" | 155
| rowspan=2|253.085133(7)
| rowspan=2|17.81(8)&nbsp;d
| β<sup>−</sup> (99.69%)
| <sup>253</sup>Es
| rowspan=2|(7/2+)
|-
| α (.31%)
| <sup>249</sup>Cm
|-
| rowspan=2|<sup>254</sup>Cf
| rowspan=2 style="text-align:right" | 98
| rowspan=2 style="text-align:right" | 156
| rowspan=2|254.087323(13)
| rowspan=2|60.5(2)&nbsp;d
| SF (99.69%)
| (various)
| rowspan=2|0+
|-
| α (.31%)
| <sup>250</sup>Cm
|-
| rowspan=3|<sup>255</sup>Cf
| rowspan=3 style="text-align:right" | 98
| rowspan=3 style="text-align:right" | 157
| rowspan=3|255.09105(22)#
| rowspan=3|85(18)&nbsp;min
| β<sup>−</sup> (99.99%)
| <sup>255</sup>Es
| rowspan=3|(7/2+)
|-
| SF (.001%)
| (various)
|-
| α (10<sup>−5</sup>%)
| <sup>251</sup>Cm
|-
|<sup>256</sup>Cf
| style="text-align:right" | 98
| style="text-align:right" | 158
|256.09344(32)#
|12.3(12)&nbsp;min
| SF
| (various)
|0+
{{Isotopes table/footer}}

==Actinides vs fission products==
{{Actinidesvsfissionproducts}}
{{clear}}

== Californium-252 ==
[[File:Cf 252 Produktion.png|thumb|production diagram]]
Californium-252 (Cf-252, <sup>252</sup>Cf) undergoes spontaneous fission with a branching ratio of 3.09% and is used in small sized [[Physics:Neutron source|neutron source]]s. Fission neutrons have an energy range of 0 to 13&nbsp;[[Physics:Electronvolt|MeV]] with a mean value of 2.3&nbsp;MeV and a most probable value of 1&nbsp;MeV.<ref name="252Cf-Dicello">{{cite journal|title = Radiation Quality of Californium-252|journal = [[Medicine:Physics in Medicine and Biology|Physics in Medicine and Biology]]|first1 = J. F.|last1 = Dicello |last2=Gross |first2=W. |last3=Kraljevic |first3=U. |year = 1972 |doi= 10.1088/0031-9155/17/3/301 |volume=17 |issue= 3 |pages = 345–355|pmid = 5070445|bibcode = 1972PMB....17..345D | s2cid=250786668 }}</ref>

This [[Physics:Isotope|isotope]] produces high neutron emissions and can be used for a number of applications in industries such as nuclear energy, medicine, and [[Chemistry:Petrochemical|petrochemical]] exploration.

=== Nuclear reactors ===
The neutron sources produced from <sup>252</sup>Cf are most notably used in the start-up of [[Physics:Nuclear reactor|nuclear reactor]]s. Once a reactor is filled with [[Physics:Nuclear fuel|nuclear fuel]], the stable neutron emissions from the source material initiates the [[Physics:Nuclear fission|fission]] chain reaction.

=== Military and defense ===
The portable isotopic neutron spectroscopy (PINS) used by United States Armed Forces, the National Guard, Homeland Security, and U.S. Customs and Border Protection, employs the use of <sup>252</sup>Cf sources to detect hazardous contents found inside [[Engineering:Shell (projectile)|artillery projectiles]], mortar projectiles, [[Engineering:Rocket|rocket]]s, bombs, land mines, and improvised explosive devices (IED).<ref name="252Cf-frontier-cf252">{{Cite web|title = Portable Isotopic Neutron Spectroscopy (PINS) for the Military|url = http://www.frontier-cf252.com/portable-isotopic-neutron-spectroscopy-military.html|website = Frontier Technology Corp.|access-date = 2016-02-24|archive-date = 2018-06-16|archive-url = https://web.archive.org/web/20180616132135/http://www.frontier-cf252.com/portable-isotopic-neutron-spectroscopy-military.html|url-status = dead}}</ref><ref name="252Cf-Martin">{{Cite journal|title = Production, distribution and applications of californium-252 neutron sources|journal = Applied Radiation and Isotopes|date = 2000-11-01|issn = 0969-8043|pmid = 11003521|pages = 785–792|volume = 53|issue = 4–5|first1 = R. C.|last1 = Martin|first2 = J. B.|last2 = Knauer|first3 = P. A.|last3 = Balo|doi=10.1016/s0969-8043(00)00214-1|url = https://digital.library.unt.edu/ark:/67531/metadc623566/}}</ref>

=== Oil and petroleum ===
In the oil industry, <sup>252</sup>Cf neutron sources are used to find layers of [[Chemistry:Petroleum|petroleum]] and water in a [[Engineering:Oil well|well]]. Instrumentation is lowered into the well which bombards the formation with high energy neutrons to determine [[Earth:Porosity|porosity]], [[Earth:Permeability (earth sciences)|permeability]], and [[Chemistry:Hydrocarbon|hydrocarbon]] presence along the length of the [[Engineering:Borehole|borehole]].<ref name="252Cf-frontier-cf252b">{{Cite web|title = Californium-252 & Antimony-Beryllium Sources|url = http://www.frontier-cf252.com|website = Frontier Technology Corp.|access-date = 2016-02-24}}</ref>

=== Medicine ===
Californium-252 has also been used in the treatment of serious forms of [[Medicine:Cancer|cancer]]. In patients with certain types of brain and cervical cancer, <sup>252</sup>Cf can be used as a more cost-effective substitute for [[Chemistry:Radium|radium]].<ref name="252Cf-Maruyama">{{Cite journal|title = Five-year cure of cervical cancer treated using californium-252 neutron brachytherapy|journal = American Journal of Clinical Oncology|date = 1984-10-01|issn = 0277-3732|pmid = 6391143|pages = 487–493|volume = 7|issue = 5|first1 = Y.|last1 = Maruyama|first2 = J. R.|last2 = van Nagell|first3 = J.|last3 = Yoneda|first4 = E.|last4 = Donaldson|first5 = M.|last5 = Hanson|first6 = A.|last6 = Martin|first7 = L. C.|last7 = Wilson|first8 = C. W.|last8 = Coffey|first9 = J.|last9 = Feola|doi=10.1097/00000421-198410000-00018|s2cid = 12553815}}</ref>

== References ==
{{Reflist}}

==Sources==
<!-- for infobox (strangely opaque sfnref is used elsewhere) -->
* {{cite book
  | title = Handbook of Chemistry and Physics
  | editor-first = David R.|editor-last = Lide
  | edition = 87th
  | date = 2006
  | publisher = CRC Press, Taylor & Francis Group
  | isbn = 978-0-8493-0487-3
  | ref = {{sfnRef|CRC|2006}}
  }}

* Isotope masses from:
**{{NUBASE 2003}}
* Isotopic compositions and standard atomic masses from:
**{{CIAAW 2005}}
* Half-life, spin, and isomer data selected from the following sources.
**{{NUBASE 2003}}
**{{NNDC}}
**{{CRC85|chapter=11}}

{{Navbox element isotopes}}

[[Category:Isotopes of californium| ]]
[[Category:Lists of isotopes by element|Californium]]

{{Sourceattribution|Isotopes of californium}}