View source for Physics:Isotopes of rutherfordium

{{Short description|Nuclides with atomic number of 104 but with different mass numbers}}
{{infobox rutherfordium isotopes}}
[[Chemistry:Rutherfordium|Rutherfordium]] (<sub>104</sub>Rf) is a [[Physics:Synthetic element|synthetic element]] and thus has no [[Physics:Stable isotope|stable isotope]]s. A [[Physics:Standard atomic weight|standard atomic weight]] cannot be given. The first [[Physics:Isotope|isotope]] to be synthesized was either <sup>259</sup>Rf in 1966 or <sup>257</sup>Rf in 1969. There are 16 known radioisotopes from <sup>253</sup>Rf to <sup>270</sup>Rf (3 of which, <sup>266</sup>Rf, <sup>268</sup>Rf, and <sup>270</sup>Rf, are unconfirmed) and several [[Physics:Nuclear isomer|isomer]]s. The longest-lived isotope is <sup>267</sup>Rf with a [[Physics:Half-life|half-life]] of 48 minutes, and the longest-lived isomer is <sup>263m</sup>Rf with a half-life of 8 seconds.

== List of isotopes ==
{{Isotopes table
|symbol=Rf
|refs=<!-- not NUBASE2016 yet (2019-07-14) -->
|notes=m, unc(), mass#, exen#, hl#, spin(), spin#, SF
}}
|-
| rowspan=2|<sup>253</sup>Rf<ref>{{cite journal |last1=Lopez-Martens |first1=A. |last2=Hauschild |first2=K. |last3=Svirikhin |first3=A. I. |last4=Asfari |first4=Z. |last5=Chelnokov |first5=M. L. |last6=Chepigin |first6=V. I. |last7=Dorvaux |first7=O. |last8=Forge |first8=M. |last9=Gall |first9=B. |last10=Isaev |first10=A. V. |last11=Izosimov |first11=I. N. |last12=Kessaci |first12=K. |last13=Kuznetsova |first13=A. A. |last14=Malyshev |first14=O. N. |last15=Mukhin |first15=R. S. |last16=Popeko |first16=A. G. |last17=Popov |first17=Yu. A. |last18=Sailaubekov |first18=B. |last19=Sokol |first19=E. A. |last20=Tezekbayeva |first20=M. S. |last21=Yeremin |first21=A. V. |title=Fission properties of Rf 253 and the stability of neutron-deficient Rf isotopes |journal=Physical Review C |date=22 February 2022 |volume=105 |issue=2 |doi=10.1103/PhysRevC.105.L021306 |url=https://journals.aps.org/prc/pdf/10.1103/PhysRevC.105.L021306 |access-date=16 June 2023 |language=en |issn=2469-9985|arxiv=2202.11802 |s2cid=247072308 }}</ref>
| rowspan=2 style="text-align:right" | 104
| rowspan=2 style="text-align:right" | 149
| rowspan=2|253.10044(44)#
| rowspan=2|9.9(1.2)&nbsp;ms
| [[Physics:Spontaneous fission|SF]] (83%)
| (various)
| rowspan=2|(1/2+)
|-
| [[Physics:Alpha decay|α]] (17%)
| <sup>249</sup>No
|-
| style="text-indent:1em" | <sup>253m1</sup>Rf
| colspan="3" style="text-indent:2em" | 200(150)#&nbsp;keV
| 52.8(4.4)&nbsp;µs
| SF
| (various)
| (7/2+)
|-
| style="text-indent:1em" | <sup>253m2</sup>Rf
| colspan="3" style="text-indent:2em" | >1020&nbsp;keV
| {{val|0.66|0.40|0.18|u=ms}}
| IT
| <sup>253m1</sup>Rf
| 
|-
| rowspan=2|<sup>254</sup>Rf<ref>{{cite journal |last1=David |first1=H. M. |last2=Chen |first2=J. |last3=Seweryniak |first3=D. |last4=Kondev |first4=F. G. |last5=Gates |first5=J. M. |last6=Gregorich |first6=K. E. |last7=Ahmad |first7=I. |last8=Albers |first8=M. |last9=Alcorta |first9=M. |last10=Back |first10=B. B. |last11=Baartman |first11=B. |last12=Bertone |first12=P. F. |last13=Bernstein |first13=L. A. |last14=Campbell |first14=C. M. |last15=Carpenter |first15=M. P. |last16=Chiara |first16=C. J. |last17=Clark |first17=R. M. |last18=Cromaz |first18=M. |last19=Doherty |first19=D. T. |last20=Dracoulis |first20=G. D. |last21=Esker |first21=N. E. |last22=Fallon |first22=P. |last23=Gothe |first23=O. R. |last24=Greene |first24=J. P. |last25=Greenlees |first25=P. T. |last26=Hartley |first26=D. J. |last27=Hauschild |first27=K. |last28=Hoffman |first28=C. R. |last29=Hota |first29=S. S. |last30=Janssens |first30=R. V. F. |last31=Khoo |first31=T. L. |last32=Konki |first32=J. |last33=Kwarsick |first33=J. T. |last34=Lauritsen |first34=T. |last35=Macchiavelli |first35=A. O. |last36=Mudder |first36=P. R. |last37=Nair |first37=C. |last38=Qiu |first38=Y. |last39=Rissanen |first39=J. |last40=Rogers |first40=A. M. |last41=Ruotsalainen |first41=P. |last42=Savard |first42=G. |last43=Stolze |first43=S. |last44=Wiens |first44=A. |last45=Zhu |first45=S. |title=Decay and Fission Hindrance of Two- and Four-Quasiparticle K Isomers in Rf 254 |journal=Physical Review Letters |date=24 September 2015 |volume=115 |issue=13 |page=132502 |doi=10.1103/PhysRevLett.115.132502 |pmid=26451549 |url=https://journals.aps.org/prl/pdf/10.1103/PhysRevLett.115.132502 |access-date=16 June 2023 |language=en |issn=0031-9007|hdl=1885/152426 |s2cid=22923276 |hdl-access=free }}</ref>
| rowspan=2 style="text-align:right" | 104
| rowspan=2 style="text-align:right" | 150
| rowspan=2|254.10005(30)#
| rowspan=2|23.2(1.1)&nbsp;µs
| SF (100%)
| (various)
| rowspan=2|0+
|-
| α (<1.5%)<ref>{{cite journal |last1=Heßberger |first1=F. P. |last2=Hofmann |first2=S. |last3=Ninov |first3=V. |last4=Armbruster |first4=P. |last5=Folger |first5=H. |last6=Münzenberg |first6=G. |last7=Schött |first7=H. J. |last8=Popeko |first8=A. G. |last9=Yeremin |first9=A. V. |last10=Andreyev |first10=A. N. |last11=Saro |first11=S. |title=Spontaneous fission and alpha-decay properties of neutron deficient isotopes 257−253104 and 258106 |journal=Zeitschrift für Physik A |date=1 December 1997 |volume=359 |issue=4 |pages=415–425 |doi=10.1007/s002180050422 |bibcode=1997ZPhyA.359..415A |s2cid=121551261 |url=https://link.springer.com/content/pdf/10.1007/s002180050422.pdf |access-date=16 June 2023 |language=en |issn=1431-5831}}</ref>
| <sup>250</sup>No
|-
| style="text-indent:1em" | <sup>254m1</sup>Rf
| colspan="3" style="text-indent:2em" | >1350&nbsp;keV
| 4.7(1.1)&nbsp;µs
| IT
| <sup>254</sup>Rf
| (8-)
|-
| style="text-indent:1em" | <sup>254m2</sup>Rf
| colspan="3" style="text-indent:2em" | 
| 247(73)&nbsp;µs
| IT
| <sup>254m1</sup>Rf
| (16+)
|-
| rowspan=3|<sup>255</sup>Rf<ref>{{cite journal |last1=Chakma |first1=R. |last2=Lopez-Martens |first2=A. |last3=Hauschild |first3=K. |last4=Yeremin |first4=A. V. |last5=Malyshev |first5=O. N. |last6=Popeko |first6=A. G. |last7=Popov |first7=Yu. A. |last8=Svirikhin |first8=A. I. |last9=Chepigin |first9=V. I. |last10=Sokol |first10=E. A. |last11=Isaev |first11=A. V. |last12=Kuznetsova |first12=A. A. |last13=Chelnokov |first13=M. L. |last14=Tezekbayeva |first14=M. S. |last15=Izosimov |first15=I. N. |last16=Dorvaux |first16=O. |last17=Gall |first17=B. |last18=Asfari |first18=Z. |title=Investigation of isomeric states in Rf 255 |journal=Physical Review C |date=31 January 2023 |volume=107 |issue=1 |page=014326 |doi=10.1103/PhysRevC.107.014326 |s2cid=256489616 |url=https://journals.aps.org/prc/pdf/10.1103/PhysRevC.107.014326 |access-date=16 June 2023 |language=en |issn=2469-9985}}</ref>
| rowspan=3 style="text-align:right" | 104
| rowspan=3 style="text-align:right" | 151
| rowspan=3|255.10127(12)#
| rowspan=3|1.69(3)&nbsp;s
| SF (50.9%)
| (various)
| rowspan=3|(9/2−)
|-
| α (49.1%)
| <sup>251</sup>No
|-
| [[Physics:Beta decay|β<sup>+</sup>]] (<6%)
| <sup>255</sup>Lr
|-
| style="text-indent:1em" | <sup>255m1</sup>Rf
| colspan="3" style="text-indent:2em" | 150&nbsp;keV
| 50(17)&nbsp;µs
| IT
| <sup>255</sup>Rf
| (5/2+)
|-
| style="text-indent:1em" | <sup>255m2</sup>Rf
| colspan="3" style="text-indent:2em" | 1103&nbsp;keV
| {{val|29|7|5|u=µs}}
| IT
| <sup>255</sup>Rf
| (19/2+)
|-
| style="text-indent:1em" | <sup>255m3</sup>Rf
| colspan="3" style="text-indent:2em" | 1303&nbsp;keV
| {{val|49|13|10|u=µs}}
| IT
| <sup>255</sup>Rf
| (25/2+)
|-
| rowspan=2|<sup>256</sup>Rf<ref>{{cite journal |last1=Jeppesen |first1=H. B. |last2=Dragojević |first2=I. |last3=Clark |first3=R. M. |last4=Gregorich |first4=K. E. |last5=Ali |first5=M. N. |last6=Allmond |first6=J. M. |last7=Beausang |first7=C. W. |last8=Bleuel |first8=D. L. |last9=Cromaz |first9=M. |last10=Deleplanque |first10=M. A. |last11=Ellison |first11=P. A. |last12=Fallon |first12=P. |last13=Garcia |first13=M. A. |last14=Gates |first14=J. M. |last15=Greene |first15=J. P. |last16=Gros |first16=S. |last17=Lee |first17=I. Y. |last18=Liu |first18=H. L. |last19=Macchiavelli |first19=A. O. |last20=Nelson |first20=S. L. |last21=Nitsche |first21=H. |last22=Pavan |first22=J. R. |last23=Stavsetra |first23=L. |last24=Stephens |first24=F. S. |last25=Wiedeking |first25=M. |last26=Wyss |first26=R. |last27=Xu |first27=F. R. |title=Multi-quasiparticle states in Rf 256 |journal=Physical Review C |date=6 March 2009 |volume=79 |issue=3 |page=031303 |doi=10.1103/PhysRevC.79.031303 |bibcode=2009PhRvC..79c1303J |url=https://journals.aps.org/prc/pdf/10.1103/PhysRevC.79.031303 |access-date=16 June 2023 |language=en |issn=0556-2813}}</ref>
| rowspan=2 style="text-align:right" | 104
| rowspan=2 style="text-align:right" | 152
| rowspan=2|256.101152(19)
| rowspan=2|6.67(9)&nbsp;ms
| SF (99.68%)
| (various)
| rowspan=2|0+
|-
| α (0.32%)<ref>{{cite journal |last1=Heßberger |first1=F. P. |last2=Hofmann |first2=S. |last3=Ninov |first3=V. |last4=Armbruster |first4=P. |last5=Folger |first5=H. |last6=Münzenberg |first6=G. |last7=Schött |first7=H. J. |last8=Popeko |first8=A. G. |last9=Yeremin |first9=A. V. |last10=Andreyev |first10=A. N. |last11=Saro |first11=S. |title=Spontaneous fission and alpha-decay properties of neutron deficient isotopes 257−253104 and 258106 |journal=Zeitschrift für Physik A |date=1 December 1997 |volume=359 |issue=4 |pages=415–425 |doi=10.1007/s002180050422 |bibcode=1997ZPhyA.359..415A |s2cid=121551261 |url=https://link.springer.com/content/pdf/10.1007/s002180050422.pdf |access-date=16 June 2023 |language=en |issn=1431-5831}}</ref>
| <sup>252</sup>No
|-
| style="text-indent:1em" | <sup>256m1</sup>Rf
| colspan="3" style="text-indent:2em" | ~1120&nbsp;keV
| 25(2)&nbsp;µs
| IT
| <sup>256</sup>Rf
| 
|-
| style="text-indent:1em" | <sup>256m2</sup>Rf
| colspan="3" style="text-indent:2em" | ~1400&nbsp;keV
| 17(2)&nbsp;µs
| IT
| <sup>256m1</sup>Rf
| 
|-
| style="text-indent:1em" | <sup>256m3</sup>Rf
| colspan="3" style="text-indent:2em" | >2200&nbsp;keV
| 27(5)&nbsp;µs
| IT
| <sup>256m2</sup>Rf
| 
|-
| rowspan=3|<sup>257</sup>Rf
| rowspan=3 style="text-align:right" | 104
| rowspan=3 style="text-align:right" | 153
| rowspan=3|257.102917(12)<ref>[https://iopscience.iop.org/article/10.1088/1674-1137/abddaf/pdf AME 2020 atomic mass evaluation]</ref>
| rowspan=3|{{val|6.2|1.2|1.0|u=s}}<ref name=257Rf>{{cite journal |last1=Hauschild |first1=K. |last2=Lopez-Martens |first2=A. |last3=Chakma |first3=R. |last4=Chelnokov |first4=M. L. |last5=Chepigin |first5=V. I. |last6=Isaev |first6=A. V. |last7=Izosimov |first7=I. N. |last8=Katrasev |first8=D. E. |last9=Kuznetsova |first9=A. A. |last10=Malyshev |first10=O. N. |last11=Popeko |first11=A. G. |last12=Popov |first12=Yu. A. |last13=Sokol |first13=E. A. |last14=Svirikhin |first14=A. I. |last15=Tezekbayeva |first15=M. S. |last16=Yeremin |first16=A. V. |last17=Asfari |first17=Z. |last18=Dorvaux |first18=O. |last19=Gall |first19=B. J. P. |last20=Kessaci |first20=K. |last21=Ackermann |first21=D. |last22=Piot |first22=J. |last23=Mosat |first23=P. |last24=Andel |first24=B. |title=Alpha-decay spectroscopy of $$^{257}$$Rf |journal=The European Physical Journal A |date=18 January 2022 |volume=58 |issue=1 |pages=6 |doi=10.1140/epja/s10050-021-00657-8 |s2cid=233394478 |url=https://link.springer.com/article/10.1140/epja/s10050-021-00657-8 |access-date=17 June 2023 |language=en |issn=1434-601X|arxiv=2104.12526 }}</ref>
| α (89.3%)
| <sup>253</sup>No
| rowspan=3|(1/2+)
|-
| β<sup>+</sup> (9.4%)<ref>{{cite journal |last1=Heßberger |first1=F. P. |last2=Antalic |first2=S. |last3=Mistry |first3=A. K. |last4=Ackermann |first4=D. |last5=Andel |first5=B. |last6=Block |first6=M. |last7=Kalaninova |first7=Z. |last8=Kindler |first8=B. |last9=Kojouharov |first9=I. |last10=Laatiaoui |first10=M. |last11=Lommel |first11=B. |last12=Piot |first12=J. |last13=Vostinar |first13=M. |title=Alpha- and EC-decay measurements of 257Rf |journal=The European Physical Journal A |date=20 July 2016 |volume=52 |issue=7 |pages=192 |doi=10.1140/epja/i2016-16192-0 |s2cid=254108438 |url=https://link.springer.com/article/10.1140/epja/i2016-16192-0 |access-date=17 June 2023 |language=en |issn=1434-601X}}</ref>
| <sup>257m</sup>Lr
|-
| SF (1.3%)<ref>{{cite journal |last1=Streicher |first1=B. |last2=Heßberger |first2=F. P. |last3=Antalic |first3=S. |last4=Hofmann |first4=S. |last5=Ackermann |first5=D. |last6=Heinz |first6=S. |last7=Kindler |first7=B. |last8=Khuyagbaatar |first8=J. |last9=Kojouharov |first9=I. |last10=Kuusiniemi |first10=P. |last11=Leino |first11=M. |last12=Lommel |first12=B. |last13=Mann |first13=R. |last14=Šáro |first14=Š. |last15=Sulignano |first15=B. |last16=Uusitalo |first16=J. |last17=Venhart |first17=M. |title=Alpha-gamma decay studies of 261Sg and 257Rf |journal=The European Physical Journal A |date=1 September 2010 |volume=45 |issue=3 |pages=275–286 |doi=10.1140/epja/i2010-11005-2 |bibcode=2010EPJA...45..275S |s2cid=120939068 |url=https://link.springer.com/content/pdf/10.1140/epja/i2010-11005-2.pdf |access-date=17 June 2023 |language=en |issn=1434-601X}}</ref>
| (various)
|-
| rowspan=4 style="text-indent:1em" | <sup>257m1</sup>Rf<ref name=257Rf/>
| rowspan=4 colspan="3" style="text-indent:2em" | 74&nbsp;keV
| rowspan=4|4.37(5) s
| α (80.54%)
| <sup>253</sup>No
| rowspan=4|(11/2-)
|-
| IT (14.2%)
| <sup>257</sup>Rf
|-
| β<sup>+</sup> (4.86%)
| <sup>257</sup>Lr
|-
| SF (0.4%)
| (various)
|-
| style="text-indent:1em" | <sup>257m2</sup>Rf<ref>{{cite journal |last1=Berryman |first1=J. S. |last2=Clark |first2=R. M. |last3=Gregorich |first3=K. E. |last4=Allmond |first4=J. M. |last5=Bleuel |first5=D. L. |last6=Cromaz |first6=M. |last7=Dragojević |first7=I. |last8=Dvorak |first8=J. |last9=Ellison |first9=P. A. |last10=Fallon |first10=P. |last11=Garcia |first11=M. A. |last12=Gros |first12=S. |last13=Lee |first13=I. Y. |last14=Macchiavelli |first14=A. O. |last15=Nitsche |first15=H. |last16=Paschalis |first16=S. |last17=Petri |first17=M. |last18=Qian |first18=J. |last19=Stoyer |first19=M. A. |last20=Wiedeking |first20=M. |title=Electromagnetic decays of excited states in Sg 261 ( Z = 106 ) and Rf 257 ( Z = 104 ) |journal=Physical Review C |date=29 June 2010 |volume=81 |issue=6 |page=064325 |doi=10.1103/PhysRevC.81.064325 |url=https://journals.aps.org/prc/pdf/10.1103/PhysRevC.81.064325 |access-date=17 June 2023 |language=en |issn=0556-2813}}</ref>
| colspan="3" style="text-indent:2em" | ~1125&nbsp;keV
| 134.9(77)&nbsp;µs
| IT
| <sup>257m1</sup>Rf
| (21/2, 23/2)
|-
| rowspan=2|<sup>258</sup>Rf<ref name=NUBASE2020/>
| rowspan=2 style="text-align:right" | 104
| rowspan=2 style="text-align:right" | 154
| rowspan=2|258.10343(3)
| rowspan=2|12.5(5)&nbsp;ms
| SF (95.1%)
| (various)
| rowspan=2|0+
|-
| α (4.9%)
| <sup>254</sup>No
|-
| style="text-indent:1em" | <sup>258m1</sup>Rf
| colspan="3" style="text-indent:2em" | 1200(300)#&nbsp;keV
| {{val|2.4|2.4|0.8|u=ms}}<ref>{{cite journal |last1=Heßberger |first1=F. P. |last2=Antalic |first2=S. |last3=Ackermann |first3=D. |last4=Andel |first4=B. |last5=Block |first5=M. |last6=Kalaninova |first6=Z. |last7=Kindler |first7=B. |last8=Kojouharov |first8=I. |last9=Laatiaoui |first9=M. |last10=Lommel |first10=B. |last11=Mistry |first11=A. K. |last12=Piot |first12=J. |last13=Vostinar |first13=M. |title=Investigation of electron capture decay of 258Db and $\alpha$decay of 258Rf |journal=The European Physical Journal A |date=11 November 2016 |volume=52 |issue=11 |pages=328 |doi=10.1140/epja/i2016-16328-2 |s2cid=125302206 |url=https://link.springer.com/article/10.1140/epja/i2016-16328-2 |access-date=18 June 2023 |language=en |issn=1434-601X}}</ref>
| IT
| <sup>258</sup>Rf
| 
|-
| style="text-indent:1em" | <sup>258m2</sup>Rf
| colspan="3" style="text-indent:2em" | 1500(500)#&nbsp;keV
| 15(10)&nbsp;µs
| IT
| <sup>258m1</sup>Rf
| 
|-
| rowspan=2|<sup>259</sup>Rf<ref name=NUBASE2020/>
| rowspan=2 style="text-align:right" | 104
| rowspan=2 style="text-align:right" | 155
| rowspan=2|259.10560(8)#
| rowspan=2| 2.63(26)&nbsp;s
| α (85%)
| <sup>255</sup>No
| rowspan=2| 3/2+#
|-
| β<sup>+</sup> (15%)
| <sup>259</sup>Lr
|-
| rowspan=2|<sup>260</sup>Rf
| rowspan=2 style="text-align:right" | 104
| rowspan=2 style="text-align:right" | 156
| rowspan=2|260.10644(22)#
| rowspan=2|21(1)&nbsp;ms
| SF
| (various)
| rowspan=2|0+
|-
| α (<20%)<ref>{{cite journal |last1=Lazarev |first1=Yu. A. |last2=Lobanov |first2=Yu. V. |last3=Oganessian |first3=Yu. Ts. |last4=Utyonkov |first4=V. K. |last5=Abdullin |first5=F. Sh. |last6=Polyakov |first6=A. N. |last7=Rigol |first7=J. |last8=Shirokovsky |first8=I. V. |last9=Tsyganov |first9=Yu. S. |last10=Iliev |first10=S. |last11=Subbotin |first11=V. G. |last12=Sukhov |first12=A. M. |last13=Buklanov |first13=G. V. |last14=Mezentsev |first14=A. N. |last15=Subotic |first15=K. |last16=Moody |first16=K. J. |last17=Stoyer |first17=N. J. |last18=Wild |first18=J. F. |last19=Lougheed |first19=R. W. |title=Decay properties of 257 No , 261 Rf , and 262 Rf |journal=Physical Review C |date=13 November 2000 |volume=62 |issue=6 |page=064307 |doi=10.1103/PhysRevC.62.064307 |bibcode=2000PhRvC..62f4307L |url=https://journals.aps.org/prc/pdf/10.1103/PhysRevC.62.064307 |access-date=17 June 2023 |language=en |issn=0556-2813}}</ref>
| <sup>256</sup>No
|-
| rowspan=3|<sup>261</sup>Rf
| rowspan=3 style="text-align:right" | 104
| rowspan=3 style="text-align:right" | 157
| rowspan=3|261.10877(5)
| rowspan=3|75(7) s<ref>{{cite journal |last1=Sylwester |first1=E. R. |last2=Adams |first2=J. L. |last3=Lane |first3=M. R. |last4=Shaughnessy |first4=D. A. |last5=Wilk |first5=P. A. |last6=Hoffman |first6=D. C. |last7=Gregorich |first7=K. E. |last8=Lee |first8=D. M. |last9=Laue |first9=C. A. |last10=McGrath |first10=C. A. |last11=Strellis |first11=D. A. |last12=Kadkhodayan |first12=B. |last13=Tuerler |first13=A. |last14=Kacher |first14=C. D. |title=On-line gas chromatographic studies of Rf, Zr, and Hf bromides |journal=Radiochimica Acta |date=1 July 2000 |volume=88 |issue=12 |pages=837–844 |doi=10.1524/ract.2000.88.12.837 |s2cid=201281991 |url=https://www.osti.gov/etdeweb/biblio/20148183 |access-date=17 June 2023 |language=English}}</ref>
| α
| <sup>257</sup>No
| rowspan=3|9/2+#
|-
| β<sup>+</sup> (<14%)<ref>{{cite web |last1=Henderson |first1=Roger |title=Chemical and Nuclear Properties of Lawrencium (Element 103) and Hahnium (Element 105) |url=https://escholarship.org/content/qt24n4v84w/qt24n4v84w.pdf |publisher=University of California, Berkeley |access-date=17 June 2023}}</ref>
| <sup>261</sup>Lr
|-
| SF (<11%)<ref>{{cite journal |last1=Kadkhodayen |first1=B. |last2=Tuerler |first2=A. |last3=Gregorich |first3=K. E. |last4=Baisden |first4=P. A. |last5=Czerwinski |first5=K. R. |last6=Eichler |first6=B. |last7=Gaeggeler |first7=H. W. |last8=Hamilton |first8=T. M. |last9=Jost |first9=D. T. |last10=Kacher |first10=C. D. |last11=Kovacs |first11=A. |last12=Kreek |first12=S. A. |last13=Lane |first13=M. R. |last14=Mohar |first14=M. F. |last15=Neu |first15=M. P. |last16=Stoyer |first16=N. J. |last17=Sylwester |first17=E. R. |last18=Lee |first18=D. M. |last19=Nurmia |first19=M. J. |last20=Seaborg |first20=G. T. |last21=Hoffman |first21=D. C. |title=On-line gas chromatographic studies of chlorides of rutherfordium and homologs Zr and Hf |journal=Radiochimica Acta |date=1 August 1996 |volume=72 |url=https://www.osti.gov/etdeweb/biblio/257926 |access-date=17 June 2023 |language=English}}</ref>
| (various)
|-
| rowspan=2 style="text-indent:1em" | <sup>261m</sup>Rf
| rowspan=2 colspan="3" style="text-indent:2em" | 70(100)#&nbsp;keV
| rowspan=2|1.9(4) s<ref>{{cite journal|title=Production and decay properties of the 1.9-s isomeric state in <sup>261</sup>Rf|first1=H.|last1=Haba|first2=D.|last2=Kaji|first3=H.|last3=Kikunaga|first4=Y.|last4=Kudou|first5=K.|last5=Morimoto|first6=K.|last6=Morita|first7=K.|last7=Ozeki|first8=T.|last8=Sumita|first9=A.|last9=Yoneda|first10=Y.|last10=Kasamatsu|first11=Y.|last11=Komori|first12=K. |last12=Ooe|first13=A.|last13=Shinohara|date=2011|journal=Physical Review C |volume=83|issue=3|page=034602|doi=10.1103/physrevc.83.034602|bibcode=2011PhRvC..83c4602H}}</ref>
| SF (73%)
| (various)
| rowspan=2|3/2+#
|-
| α (27%)
| <sup>257</sup>No
|-
| <sup>262</sup>Rf
| style="text-align:right" | 104
| style="text-align:right" | 158
| 262.10993(24)#
| {{val|210|128|58|u=ms}}<ref>{{cite web |last1=Gorshkov |display-authors=et. al. |title=Measurements of 260-262Rf produced in 22Ne + 244Pu fusion reaction at TASCA |url=https://download.uni-mainz.de/fb09-kernchemie/jb2008/a14.pdf |publisher=GSI |access-date=16 June 2023}}</ref>
| SF
| (various)
| 0+
|-
| style="text-indent:1em" | <sup>262m</sup>Rf
| colspan="3" style="text-indent:2em" | 600(400)#&nbsp;keV
| 47(5)&nbsp;ms
| SF
| (various)
| high
|-
| rowspan=2|<sup>263</sup>Rf
| rowspan=2 style="text-align:right" | 104
| rowspan=2 style="text-align:right" | 159
| rowspan=2|263.1125(2)#
| rowspan=2|11(3)&nbsp;min
| SF (77%)
| (various)
| rowspan=2|3/2+#
|-
| α (23%)<ref>{{cite journal |last1=Kacher |first1=Christian D. |title=Chemical and nuclear properties of Rutherfordium (Element 104) |date=30 October 1995 |url=https://www.osti.gov/biblio/193914 |access-date=18 June 2023 |publisher=Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States) |doi=10.2172/193914 |osti=193914 |language=English}}</ref>
| <sup>259</sup>No
|-
| style="text-indent:1em" | <sup>263m</sup>Rf<ref group="n">Not directly synthesized, occurs in [[Physics:Decay chain|decay chain]] of <sup>271</sup>Hs</ref>
| colspan="3" style="text-indent:2em" | 
| {{val|8|40|4|u=s}}<ref>{{cite journal |last1=Dvorak |first1=J. |last2=Brüchle |first2=W. |last3=Chelnokov |first3=M. |last4=Düllmann |first4=Ch. E. |last5=Dvorakova |first5=Z. |last6=Eberhardt |first6=K. |last7=Jäger |first7=E. |last8=Krücken |first8=R. |last9=Kuznetsov |first9=A. |last10=Nagame |first10=Y. |last11=Nebel |first11=F. |last12=Nishio |first12=K. |last13=Perego |first13=R. |last14=Qin |first14=Z. |last15=Schädel |first15=M. |last16=Schausten |first16=B. |last17=Schimpf |first17=E. |last18=Schuber |first18=R. |last19=Semchenkov |first19=A. |last20=Thörle |first20=P. |last21=Türler |first21=A. |last22=Wegrzecki |first22=M. |last23=Wierczinski |first23=B. |last24=Yakushev |first24=A. |last25=Yeremin |first25=A. |title=Observation of the 3 n Evaporation Channel in the Complete Hot-Fusion Reaction Mg 26 + Cm 248 Leading to the New Superheavy Nuclide Hs 271 |journal=Physical Review Letters |date=3 April 2008 |volume=100 |issue=13 |page=132503 |doi=10.1103/PhysRevLett.100.132503 |pmid=18517941 |url=https://journals.aps.org/prl/pdf/10.1103/PhysRevLett.100.132503 |access-date=16 June 2023 |language=en |issn=0031-9007}}</ref>
| SF
| (various)
| 
|-
| <sup>265</sup>Rf<ref group="n">Not directly synthesized, occurs in [[Physics:Decay chain|decay chain]] of <sup>285</sup>Fl</ref>
| style="text-align:right" | 104
| style="text-align:right" | 161
| 265.11668(39)#
| {{val|1.1|0.8|0.3|u=min}}<ref name="PuCa2017" />
| SF
| (various)
| 
|-
| <sup>266</sup>Rf<ref group="n" name="uc">Discovery of this isotope is unconfirmed</ref><ref group="n">Not directly synthesized, occurs in decay chain of <sup>282</sup>Nh</ref>
| style="text-align:right" | 104
| style="text-align:right" | 162
| 266.11817(50)#
| 23&nbsp;s#<ref name="Rf266">{{cite journal |doi=10.1103/PhysRevC.76.011601 |date=2007 |issue=1 |volume=76 |journal=Physical Review C |title=Synthesis of the isotope 282113 in the Np237+Ca48 fusion reaction |author=Oganessian, Yu. Ts. | display-authors=1 |bibcode = 2007PhRvC..76a1601O |last2=Utyonkov |first2=V. |last3=Lobanov |first3=Yu. |last4=Abdullin |first4=F. |last5=Polyakov |first5=A. |last6=Sagaidak |first6=R. |last7=Shirokovsky |first7=I. |last8=Tsyganov |first8=Yu. |last9=Voinov |first9=A. |page=011601 }}</ref><ref name="IslandOfStability">{{cite journal |last1=Oganessian |first1=Yuri |title=Nuclei in the "Island of Stability" of Superheavy Elements |journal=Journal of Physics: Conference Series |date=8 February 2012 |volume=337 |issue=1 |pages=012005 |doi=10.1088/1742-6596/337/1/012005 |bibcode=2012JPhCS.337a2005O |doi-access=free }}</ref>
| SF
| (various)
| 0+
|-
| <sup>267</sup>Rf<ref group="n">Not directly synthesized, occurs in decay chain of <sup>287</sup>Fl</ref>
| style="text-align:right" | 104
| style="text-align:right" | 163
| 267.12179(62)#
| {{val|48|23|12|u=min}}<ref name=PuCa2022/>
| SF
| (various)
| 13/2−#
|-
| <sup>268</sup>Rf<ref group="n" name="uc" /><ref group="n">Not directly synthesized, occurs in decay chain of <sup>288</sup>Mc</ref>
| style="text-align:right" | 104
| style="text-align:right" | 164
| 268.12397(77)#
| 1.4&nbsp;s#<ref name="IslandOfStability" /><ref name="Db268">{{cite web |url=http://cdsweb.cern.ch/record/831577 |title=CERN Document Server: Record#831577: Chemical Identification of Dubnium as a Decay Product of Element 115 Produced in the Reaction 48Ca + 243Am |publisher=Cdsweb.cern.ch |access-date=2010-09-19}}</ref>
| SF
| (various)
| 0+
|-
| <sup>270</sup>Rf<ref name="270Db">{{cite book|url=https://books.google.com/books?id=zVrdAAAAQBAJ&q=isotope+(270)Rf&pg=PT305|title=Encyclopedia of Nuclear Physics and its Applications|first=Reinhard|last=Stock|date=13 September 2013|publisher=John Wiley & Sons|access-date=8 April 2018|via=Google Books|isbn=9783527649266}}</ref><ref group="n" name="uc" /><ref group="n">Not directly synthesized, occurs in decay chain of <sup>294</sup>Ts</ref>
| style="text-align:right" | 104
| style="text-align:right" | 166
|
| 20&nbsp;ms#<ref name="IslandOfStability" /><ref>{{cite web |url=https://agenda.infn.it/getFile.py/access?contribId=80&sessionId=7&resId=0&materialId=slides&confId=5235 |title=Exploration of Nuclear Structure and Decay of Heaviest Elements at GSI - SHIP  |publisher=agenda.infn.it |author=Fritz Peter Heßberger |access-date=2016-09-10}}</ref>
| SF
| (various)
| 0+
{{Isotopes table/footer}}

== Nucleosynthesis ==
Super-heavy elements such as rutherfordium are produced by bombarding lighter elements in [[Physics:Particle accelerator|particle accelerator]]s that induces fusion reactions. Whereas most of the isotopes of rutherfordium can be synthesized directly this way, some heavier ones have only been observed as decay products of elements with higher [[Physics:Atomic number|atomic number]]s.<ref name="fusion">{{cite journal |last1=Barber |first1=Robert C. |last2=Gäggeler |first2=Heinz W. |last3=Karol |first3=Paul J. |last4=Nakahara |first4=Hiromichi |last5=Vardaci |first5=Emanuele |last6=Vogt |first6=Erich |title=Discovery of the element with atomic number 112 (IUPAC Technical Report) |journal=Pure and Applied Chemistry |volume=81 |issue=7 |page=1331 |year=2009 |doi=10.1351/PAC-REP-08-03-05|doi-access=free }}</ref>

Depending on the energies involved, the former are separated into "hot" and "cold". In hot fusion reactions, very light, high-energy projectiles are accelerated toward very heavy targets ([[Chemistry:Actinide|actinide]]s), giving rise to compound nuclei at high excitation energy (~40–50&nbsp;[[Physics:Electronvolt|MeV]]) that may either fission or evaporate several (3 to 5) neutrons.<ref name="fusion" /> In cold fusion reactions, the produced fused nuclei have a relatively low excitation energy (~10–20&nbsp;MeV), which decreases the probability that these products will undergo fission reactions. As the fused nuclei cool to the [[Physics:Ground state|ground state]], they require emission of only one or two neutrons, and thus, allows for the generation of more neutron-rich products.<ref name="AM89">{{Cite journal |first1=Peter |last1=Armbruster |name-list-style=amp |first2=Gottfried |last2=Munzenberg |title=Creating superheavy elements |journal=Scientific American |volume=34 |pages=36–42 |year=1989}}</ref> The latter is a distinct concept from that of where nuclear fusion claimed to be achieved at room temperature conditions (see [[Physics:Cold fusion|cold fusion]]).<ref>{{cite journal |doi=10.1016/0022-0728(89)80006-3 |title=Electrochemically induced nuclear fusion of deuterium |year=1989 |last1=Fleischmann |first1=Martin |last2=Pons |first2=Stanley |journal=Journal of Electroanalytical Chemistry and Interfacial Electrochemistry |volume=261 |issue=2 |pages=301–308}}</ref>

===Hot fusion studies===
The synthesis of rutherfordium was first attempted in 1964 by the team at Dubna using the hot fusion reaction of [[Chemistry:Neon|neon]]-22 projectiles with [[Chemistry:Plutonium|plutonium]]-242 targets:
:{{nuclide|link=yes|plutonium|242}} + {{nuclide|link=yes|neon|22}} → {{nuclide|rutherfordium|264−x}} + 3 or 5 {{SubatomicParticle|link=yes|Neutron}}.
The first study produced evidence for a [[Physics:Spontaneous fission|spontaneous fission]] with a 0.3&nbsp;second [[Physics:Half-life|half-life]] and another one at 8&nbsp;seconds. While the former observation was eventually retracted, the latter eventually became associated with the <sup>259</sup>Rf isotope.<ref name="93TWG">[http://www.iupac.org/publications/pac/1993/pdf/6508x1757.pdf "Discovery of the transneptunium elements"], '''IUPAC/IUPAP Technical Report''', ''Pure Appl. Chem.'', Vol. 65, No. 8, pp. 1757-1814,1993. Retrieved on 2008-03-04</ref> In 1966, the Soviet team repeated the experiment using a chemical study of volatile chloride products. They identified a volatile chloride with eka-hafnium properties that decayed fast through spontaneous fission. This gave strong evidence for the formation of RfCl<sub>4</sub>, and although a half-life was not accurately measured, later evidence suggested that the product was most likely <sup>259</sup>Rf. The team repeated the experiment several times over the next few years, and in 1971, they revised the spontaneous fission half-life for the isotope at 4.5&nbsp;seconds.<ref name="93TWG" />

In 1969, researchers at the [[Organization:University of California|University of California]] led by [[Biography:Albert Ghiorso|Albert Ghiorso]], tried to confirm the original results reported at Dubna. In a reaction of [[Chemistry:Curium|curium]]-248 with [[Physics:Oxygen-16|oxygen-16]], they were unable to confirm the result of the Soviet team, but managed to observe the spontaneous fission of <sup>260</sup>Rf with a very short half-life of 10–30&nbsp;ms:
:{{nuclide|link=yes|curium|248}} + {{nuclide|link=yes|oxygen|16}} → {{nuclide|rutherfordium|260}} + 4 {{SubatomicParticle|link=yes|Neutron}}.
In 1970, the American team also studied the same reaction with [[Physics:Oxygen-18|oxygen-18]] and identified <sup>261</sup>Rf with a half-life of 65&nbsp;seconds (later refined to 75&nbsp;seconds).<ref name="70Gh01">{{cite journal |doi=10.1016/0370-2693(70)90595-2 |title=<sup>261</sup>Rf; new isotope of element 104 |year=1970 |first1= A. |last1=Ghiorso |first2=M. |last2=Nurmia |first3=K. |last3=Eskola |first4=P. |last4=Eskola |journal=Physics Letters B |volume=32 |issue=2 |pages=95–98 |bibcode=1970PhLB...32...95G}}</ref><ref>{{Cite journal |author=Sylwester |title=On-line gas chromatographic studies of Rf, Zr, and Hf bromides |journal=Radiochimica Acta |volume=88 |issue=12_2000 |page=837 |year=2000 |doi=10.1524/ract.2000.88.12.837 |last2=Gregorich |first2=K. E. |last3=Lee |first3=D. M. |last4=Kadkhodayan |first4=B. |last5=Türler |first5=A. |last6=Adams |first6=J. L. |last7=Kacher |first7=C. D. |last8=Lane |first8=M. R. |last9=Laue |first9=C.|display-authors=2 |last10=McGrath |first10=C. A. |s2cid=201281991 |url=https://zenodo.org/record/1236275 }}</ref> Later experiments at the [[Organization:Lawrence Berkeley National Laboratory|Lawrence Berkeley National Laboratory]] in California also revealed the formation of a short-lived isomer of <sup>262</sup>Rf (which undergoes spontaneous fission with a half-life of 47&nbsp;ms),<ref>{{cite journal |doi=10.1103/PhysRevC.31.1801 |title=Spontaneous fission of rutherfordium isotopes |year=1985 |last1=Somerville |first1=L. P. |last2=Nurmia |first2=M. J. |last3=Nitschke |first3=J. M. |last4=Ghiorso |first4=A. |last5=Hulet |first5=E. K. |last6=Lougheed |first6=R. W. |journal=Physical Review C |volume=31 |issue=5 |pages=1801–1815 |pmid=9952719 |bibcode=1985PhRvC..31.1801S|url=https://zenodo.org/record/1233765 }}</ref> and spontaneous fission activities with long lifetimes tentatively assigned to <sup>263</sup>Rf.<ref name="Rf263" />

[[File:Rutherfordium experimental setup.jpeg|thumb|350px|Diagram of the experimental set-up used in the discovery of isotopes <sup>257</sup>Rf and <sup>259</sup>Rf]]
The reaction of [[Chemistry:Californium|californium]]-249 with [[Physics:Carbon-13|carbon-13]] was also investigated by the Ghiorso team, which indicated the formation of the short-lived <sup>258</sup>Rf (which undergoes spontaneous fission in 11&nbsp;ms):<ref name="69Gh01">{{cite journal | last1 = Ghiorso | display-authors = etal   | year = 1969 | title = Positive Identification of Two Alpha-Particle-Emitting Isotopes of Element 104 | journal = Phys. Rev. Lett. | volume = 22 | issue = 24| pages = 1317–1320 | doi=10.1103/physrevlett.22.1317| bibcode = 1969PhRvL..22.1317G| url = https://escholarship.org/uc/item/3fm666nq | doi-access = free }}</ref>
:{{nuclide|link=yes|californium|249}} + {{nuclide|link=yes|carbon|13}} → {{nuclide|rutherfordium|258}} + 4 {{SubatomicParticle|link=yes|Neutron}}.
In trying to confirm these results by using [[Physics:Carbon-12|carbon-12]] instead, they also observed the first [[Physics:Alpha decay|alpha decay]]s from <sup>257</sup>Rf.<ref name="69Gh01" />

The reaction of [[Chemistry:Berkelium|berkelium]]-249 with [[Chemistry:Nitrogen|nitrogen]]-14 was first studied in Dubna in 1977, and in 1985, researchers there confirmed the formation of the <sup>260</sup>Rf isotope which quickly undergoes spontaneous fission in 28&nbsp;ms:<ref name="93TWG" />
:{{nuclide|link=yes|berkelium|249}} + {{nuclide|link=yes|nitrogen|14}} → {{nuclide|rutherfordium|260}} + 3 {{SubatomicParticle|link=yes|Neutron}}.

In 1996 the isotope <sup>262</sup>Rf was observed in LBNL from the fusion of plutonium-244 with neon-22:
:{{nuclide|link=yes|plutonium|244}} + {{nuclide|link=yes|neon|22}} → {{nuclide|rutherfordium|266−x}} + 4 or 5 {{SubatomicParticle|link=yes|Neutron}}.
The team determined a half-life of 2.1&nbsp;seconds, in contrast to earlier reports of 47&nbsp;ms and suggested that the two half-lives might be due to different isomeric states of <sup>262</sup>Rf.<ref name="96La01">{{cite journal |doi =10.1103/PhysRevC.53.2893| title =Spontaneous fission properties of 104262Rf |year =1996 |author=Lane |journal =Physical Review C |volume =53 |issue = 6 |pages =2893–2899 |bibcode = 1996PhRvC..53.2893L |last2 =Gregorich |first2 =K. |last3 =Lee |first3 =D. |last4 =Mohar |first4 =M. |last5 =Hsu |first5 =M. |last6 =Kacher |first6 =C. |last7 =Kadkhodayan |first7 =B. |last8 =Neu |first8 =M. |last9 =Stoyer |first9 =N. |display-authors =2|last10 =Sylwester|first10 =E. R.|last11 =Yang|first11 =J. C.|last12 =Hoffman|first12 =D. C.| pmid =9971276 }}</ref> Studies on the same reaction by a team at Dubna, lead to the observation in 2000 of alpha decays from <sup>261</sup>Rf and spontaneous fissions of <sup>261m</sup>Rf.<ref name="j1">{{cite journal |last1=Lazarev |first1=Yu |title=Decay properties of 257No, 261Rf, and 262Rf |journal=Physical Review C |volume=62 |issue=6 |year=2000 |doi=10.1103/PhysRevC.62.064307 |bibcode = 2000PhRvC..62f4307L |last2=Lobanov |first2=Yu. |last3=Oganessian |first3=Yu. |last4=Utyonkov |first4=V. |last5=Abdullin |first5=F. |last6=Polyakov |first6=A. |last7=Rigol |first7=J. |last8=Shirokovsky |first8=I. |last9=Tsyganov |first9=Yu. |display-authors=1 |last10=Iliev |first10=S. |last11=Subbotin |first11=V. |last12=Sukhov |first12=A. |last13=Buklanov |first13=G. |last14=Mezentsev |first14=A. |last15=Subotic |first15=K. |last16=Moody |first16=K. |last17=Stoyer |first17=N. |last18=Wild |first18=J. |last19=Lougheed |first19=R. |pages=64307 }}</ref>

The hot fusion reaction using a uranium target was first reported at Dubna in 2000:
:{{nuclide|link=yes|uranium|238}} + {{nuclide|link=yes|magnesium|26}} → {{nuclide|rutherfordium|264−x}} + x {{SubatomicParticle|link=yes|Neutron}} (x = 3, 4, 5, 6).
They observed decays from <sup>260</sup>Rf and <sup>259</sup>Rf, and later for <sup>259</sup>Rf. In 2006, as part of their program on the study of uranium targets in hot fusion reactions, the team at LBNL also observed <sup>261</sup>Rf.<ref name="j1" /><ref name="uranium">{{cite web |url = http://rnc.lbl.gov/nsd/annualreport2005/contributions/Gregorich_LE.pdf| title = Systematic Study of Heavy Element Production in Compound Nucleus Reactions with <sup>238</sup>U Targets |last= Gregorich |first=K. E.|publisher = LBNL annual report |year = 2005 |access-date = 2008-02-29|display-authors=0}}</ref><ref>{{cite journal |doi =10.1103/PhysRevC.77.034603 |title =Synthesis of rutherfordium isotopes in the <sup>238</sup>U(<sup>26</sup>Mg,xn)<sup>264−x</sup>Rf reaction and study of their decay properties |journal =Physical Review C |volume =77 |issue =3 |year =2008 |author = Gates |bibcode = 2008PhRvC..77c4603G |last2 =Garcia |first2 =M. A. |last3 =Gregorich |first3 =K. E. |last4 =Düllmann |first4 =Ch. E. |last5 =Dragojević |first5 =I. |last6 =Dvorak |first6 =J. |last7 =Eichler |first7 =R. |last8 =Folden |first8 =C. M. |last9 =Loveland |first9 =W. |display-authors =2 |last10 =Nelson |first10 =S. L. |last11 =Pang |first11 =G. K. |last12 =Stavsetra |first12 =L. |last13 =Sudowe |first13 =R. |last14 =Türler |first14 =A. |last15 =Nitsche |first15 =H. |pages =34603 |s2cid =42983895 |url =https://www.dora.lib4ri.ch/psi/islandora/object/psi%3A18838 }}</ref>

===Cold fusion studies===
The first cold fusion experiments involving element 104 were done in 1974 at Dubna, by using light [[Physics:Titanium-50|titanium-50]] nuclei aimed at lead-208 isotope targets:
:{{nuclide|link=yes|lead|208}} + {{nuclide|link=yes|titanium|50}} → {{nuclide|rutherfordium|258−x}} + x {{SubatomicParticle|link=yes|Neutron}} (x = 1, 2, or 3).
The measurement of a spontaneous fission activity was assigned to <sup>256</sup>Rf,<ref>{{cite journal |doi =10.1016/0375-9474(75)91140-9 |title =Experiments on the synthesis of neutron-deficient kurchatovium isotopes in reactions induced by <sup>50</sup>Ti Ions |year = 1975 |last1 =Oganessian |first1 = Yu. Ts. |last2=Demin |first2=A. G. |last3=Il'inov |first3=A. S. |last4=Tret'yakova |first4=S. P. |last5=Pleve |first5=A. A. |last6=Penionzhkevich |first6=Yu. É. |last7=Ivanov |first7=M. P. |last8= Tret'yakov |first8=Yu. P. | journal =Nuclear Physics A |volume =38 |issue = 6 |pages =492–501 |bibcode = 1975NuPhA.239..157O }}</ref> while later studies done at the Gesellschaft für Schwerionenforschung Institute (GSI), also measured decay properties for the isotopes <sup>257</sup>Rf, and <sup>255</sup>Rf.<ref>{{cite journal |doi=10.1007/BF01493453 |title=Study of evaporation residues produced in reactions of <sup>207</sup>,<sup>208</sup>Pb with <sup>50</sup>Ti |year=1985 |last1=Heßberger |first1=F. P. |last2=Münzenberg |first2=G. |last3=Hofmann |first3=S. |last4=Reisdorf |first4=W. |last5=Schmidt |first5=K. H. |last6=Schött |first6=H. J. |last7=Armbruster |first7=P. |last8=Hingmann |first8=R. |last9=Thuma |first9=B. |last10=Vermeulen |first10=D. |display-authors=2 |journal=Zeitschrift für Physik A |volume=321 |issue=2 |pages=317–327 |bibcode=1985ZPhyA.321..317H|s2cid=118720320 }}</ref><ref name="97He01">{{cite journal |doi =10.1007/s002180050422 |title =Spontaneous fission and alpha-decay properties of neutron deficient isotopes <sup>257−253</sup>104 and <sup>258</sup>106 |year =1997 |last1 = Heßberger |first1 = F. P. |last2=Hofmann |first2=S. |last3=Ninov |first3=V. |last4=Armbruster |first4=P. |last5=Folger |first5=H. |last6=Münzenberg |first6=G. |last7=Schött |first7=H. J. |last8=Popeko |first8=A. K. |last9=Yeremin |first9=A. V. |last10=Andreyev |first10=A. N. |last11=Saro |first11=S. |journal =Zeitschrift für Physik A |volume =359 |issue =4 |pages =415–425 |bibcode = 1997ZPhyA.359..415A |s2cid =121551261 }}</ref>

In 1974 researchers at Dubna investigated the reaction of [[Physics:Lead-207|lead-207]] with titanium-50 to produce the isotope <sup>255</sup>Rf.<ref name="Rf255">{{cite journal |title=Decay properties of neutron-deficient isotopes <sup>256,257</sup>Db, <sup>255</sup>Rf, <sup>252,253</sup>Lr"] |last1=Heßberger |first1=F. P. |last2=Hofmann |first2=S. |last3=Ackermann |first3=D. |last4=Ninov |first4=V. |last5=Leino |first5=M. |last6=Münzenberg |first6=G. |last7=Saro |first7=S. |last8=Lavrentev |first8=A. |last9=Popeko |first9=A. G. |last10=Yeremin |first10=A. V. |last11=Stodel |first11=Ch. |journal=European Physical Journal A |volume=12 |issue=1 |pages=57–67 |year=2001 |doi=10.1007/s100500170039 |bibcode=2001EPJA...12...57H|s2cid=117896888 }}</ref> In a 1994 study at GSI using the lead-206 isotope, <sup>255</sup>Rf as well as <sup>254</sup>Rf were detected. <sup>253</sup>Rf was similarly detected that year when lead-204 was used instead.<ref name="97He01" />

===Decay studies===
Most isotopes with an [[Physics:Atomic mass|atomic mass]] below 262 have also observed as decay products of elements with a higher [[Physics:Atomic number|atomic number]], allowing for refinement of their previously measured properties. Heavier isotopes of rutherfordium have only been observed as decay products. For example, a few alpha decay events terminating in <sup>267</sup>Rf were observed in the decay chain of [[Chemistry:Darmstadtium|darmstadtium]]-279 since 2004:
:{{nuclide|darmstadtium|279}} → {{nuclide|hassium|275}} + {{SubatomicParticle|alpha}} → {{nuclide|seaborgium|271}} + {{SubatomicParticle|link=no|alpha}} → {{nuclide|rutherfordium|267}} + {{SubatomicParticle|link=no|alpha}}.
This further underwent spontaneous fission with a half-life of about 1.3&nbsp;h.<ref name="springerlink1">{{cite book |author=Hofmann, S. |title=The Euroschool Lectures on Physics with Exotic Beams, Vol. III Lecture Notes in Physics |publisher=Springer |year= 2009 |pages=203–252 |doi=10.1007/978-3-540-85839-3_6 |volume=764|chapter=Superheavy Elements |isbn=978-3-540-85838-6 }}</ref><ref>{{cite journal|title=Measurements of cross sections and decay properties of the isotopes of elements 112, 114, and 116 produced in the fusion reactions <sup>233,238</sup>U, <sup>242</sup>Pu, and <sup>248</sup>Cm+<sup>48</sup>Ca|doi=10.1103/PhysRevC.70.064609|year=2004|journal=Physical Review C|volume=70|page=064609|last1=Oganessian|first1=Yu. Ts.|last2=Utyonkov|first2=V.|last3=Lobanov|first3=Yu.|last4=Abdullin|first4=F.|last5=Polyakov|first5=A.|last6=Shirokovsky|first6=I.|last7=Tsyganov|first7=Yu.|last8=Gulbekian|first8=G.|last9=Bogomolov|first9=S.|first10=B. N. |last10=Gikal|first11=A. N. |last11=Mezentsev|first12=S. |last12=Iliev|first13=V. G. |last13=Subbotin|first14=A. M. |last14=Sukhov|first15=A. A. |last15=Voinov|first16=G. V. |last16=Buklanov|first17=K. |last17=Subotic|first18=V. I. |last18=Zagrebaev|first19=M. G. |last19=Itkis|first20=J. B. |last20=Patin|first21=K. J. |last21=Moody|first22=J. F. |last22=Wild|first23=M. A. |last23=Stoyer|first24=N. J. |last24=Stoyer|first25=D. A. |last25=Shaughnessy|first26=J. M. |last26=Kenneally|first27=P. A. |last27=Wilk|first28=R. W. |last28=Lougheed|first29=R. I. |last29=Il'kaev|first30=S. P. |last30=Vesnovskii|display-authors=10|bibcode = 2004PhRvC..70f4609O|issue=6|url=http://www1.jinr.ru/Preprints/2004/160(E7-2004-160).pdf}}</ref><ref>{{cite journal |last1=Oganessian |first1=Yuri |title=Heaviest nuclei from 48Ca-induced reactions |journal=Journal of Physics G: Nuclear and Particle Physics |volume=34 |issue=4 |pages=R165–R242 |year=2007 |doi=10.1088/0954-3899/34/4/R01 |bibcode = 2007JPhG...34R.165O }}</ref>

Investigations on the synthesis of the [[Chemistry:Dubnium|dubnium]]-263 isotope in 1999 at the [[Organization:University of Bern|University of Bern]] revealed events consistent with [[Physics:Electron capture|electron capture]] to form <sup>263</sup>Rf. A rutherfordium fraction was separated, and several spontaneous fission events with long half-lives of about 15 minutes were observed, as well as alpha decays with half-lives of about 10 minutes.<ref name="Rf263">{{cite journal |url=http://www.ulrich-rieth.de/publikationen/RCA0301_059.PDF |title=An EC-branch in the decay of 27-s<sup>263</sup>Db: Evidence for the new isotope<sup>263</sup>Rf |author=Kratz |journal=Radiochim. Acta |volume=91 |issue=1–2003 |pages=59–62 |year=2003 |doi=10.1524/ract.91.1.59.19010 |last2=Nähler |first2=A. |last3=Rieth |first3=U. |last4=Kronenberg |first4=A. |last5=Kuczewski |first5=B. |last6=Strub |first6=E. |last7=Brüchle |first7=W. |last8=Schädel |first8=M. |last9=Schausten |first9=B. |s2cid=96560109 |display-authors=2 |url-status=dead |archive-url=https://web.archive.org/web/20090225154858/http://www.ulrich-rieth.de/publikationen/RCA0301_059.PDF |archive-date=2009-02-25 }}</ref> Reports on the decay chain of [[Chemistry:Flerovium|flerovium]]-285 in 2010 showed five sequential alpha decays that terminate in <sup>265</sup>Rf, which further undergoes spontaneous fission with a half-life of 152 seconds.<ref name="10El">{{cite journal |last1=Ellison |first1=P. |last2=Gregorich |first2=K. |last3=Berryman |first3=J. |last4=Bleuel |first4=D. |last5=Clark |first5=R. |last6=Dragojević |first6=I. |last7=Dvorak |first7=J. |last8=Fallon |first8=P. |last9=Fineman-Sotomayor |first9=C. |last10=N.N. |display-authors=9 | title=New Superheavy Element Isotopes: <math>^{242}Pu(^{48}Ca,5n)^{285}114</math> |journal=Physical Review Letters |volume=105 |year=2010 |doi=10.1103/PhysRevLett.105.182701 |bibcode=2010PhRvL.105r2701E|first10=J. M. |last11=Gothe |first11=O. R. |last12=Lee |first12=I. Y. |last13=Loveland |first13=W. D. |last14=McLaughlin |first14=J. P. |last15=Paschalis |first15=S. |last16=Petri |first16=M. |last17=Qian |first17=J. |last18=Stavsetra |first18=L. |last19=Wiedeking |first19=M. |last20=Nitsche |first20=H. |issue=18 |pages=182701 |pmid=21231101 |url=https://digital.library.unt.edu/ark:/67531/metadc831769/ }}</ref>

Some experimental evidence was obtained in 2004 for an even heavier isotope, <sup>268</sup>Rf, in the decay chain of an isotope of [[Chemistry:Moscovium|moscovium]]:
:{{nuclide|moscovium|288}} → {{nuclide|nihonium|284}} + {{SubatomicParticle|link=no|alpha}} → {{nuclide|roentgenium|280}} + {{SubatomicParticle|link=no|alpha}} → {{nuclide|meitnerium|276}} + {{SubatomicParticle|link=no|alpha}} → {{nuclide|bohrium|272}} + {{SubatomicParticle|link=no|alpha}} → {{nuclide|dubnium|268}} + {{SubatomicParticle|link=no|alpha}} ? → {{nuclide|rutherfordium|268}} + {{SubatomicParticle|link=yes|Electron Neutrino}}.
However, the last step in this chain was uncertain. After observing the five alpha decay events that generate [[Chemistry:Dubnium|dubnium]]-268, spontaneous fission events were observed with a long half-life. It is unclear whether these events were due to direct spontaneous fission of <sup>268</sup>Db, or <sup>268</sup>Db produced [[Physics:Electron capture|electron capture]] events with long half-lives to generate <sup>268</sup>Rf. If the latter is produced and decays with a short half-life, the two possibilities cannot be distinguished.<ref name="autogenerated1">{{cite journal |last1=Oganessian |first1=Yury Ts |last2=Dmitriev |first2=Sergey N |title=Superheavy elements in D I Mendeleev's Periodic Table |journal=Russian Chemical Reviews |volume=78 |issue=12 |pages=1077–1087 |year=2009 |doi=10.1070/RC2009v078n12ABEH004096 |bibcode = 2009RuCRv..78.1077O |s2cid=250848732 }}</ref> Given that the [[Physics:Electron capture|electron capture]] of <sup>268</sup>Db cannot be detected, these spontaneous fission events may be due to <sup>268</sup>Rf, in which case the half-life of this isotope cannot be extracted.<ref name="Db268" /><ref>{{cite book |url=https://books.google.com/books?id=yb9xTj72vNAC&pg=PA344 |last=Krebs |first=Robert E. |title=The history and use of our earth's chemical elements: a reference guide |page=344 |publisher=Greenwood Publishing Group |access-date=2010-09-19 |isbn=978-0-313-33438-2 |year=2006}}</ref> A similar mechanism is proposed for the formation of the even heavier isotope <sup>270</sup>Rf as a short-lived daughter of <sup>270</sup>Db (in the decay chain of <sup>294</sup>Ts, first synthesized in 2010) which then undergoes spontaneous fission:<ref name="270Db" />
:{{nuclide|tennessine|294}} → {{nuclide|moscovium|290}} + {{SubatomicParticle|link=no|alpha}} → {{nuclide|nihonium|286}} + {{SubatomicParticle|link=no|alpha}} → {{nuclide|roentgenium|282}} + {{SubatomicParticle|link=no|alpha}} → {{nuclide|meitnerium|278}} + {{SubatomicParticle|link=no|alpha}} → {{nuclide|bohrium|274}} + {{SubatomicParticle|link=no|alpha}} → {{nuclide|dubnium|270}} + {{SubatomicParticle|link=no|alpha}} ? → {{nuclide|rutherfordium|270}} + {{SubatomicParticle|link=yes|Electron Neutrino}}.

According to a 2007 report on the synthesis of [[Chemistry:Nihonium|nihonium]], the isotope <sup>282</sup>Nh was twice observed to undergo a similar decay to form <sup>266</sup>Db. In one case this underwent spontaneous fission with a half-life of 22 minutes. Given that the electron capture of <sup>266</sup>Db cannot be detected, these spontaneous fission events may be due to <sup>266</sup>Rf, in which case the half-life of this isotope cannot be extracted. In the other case, no spontaneous fission event was observed; it could have been missed, or <sup>266</sup>Db might have undergone two more alpha decays to long-lived <sup>258</sup>Md, with a half-life (51.5&nbsp;d) longer than the total time of the experiment.<ref name="Rf266" /><ref>{{cite book |last=Hofmann |first=S. |title=The Euroschool Lectures on Physics with Exotic Beams, Vol. III Lecture Notes in Physics |publisher=Springer |year= 2009 |page=229 |doi=10.1007/978-3-540-85839-3_6 |volume=764|chapter=Superheavy Elements |isbn=978-3-540-85838-6 }}</ref>
{{Clear}}

===Nuclear isomerism===
[[File:257Rf decay scheme 2006.png|thumb|220px|Currently suggested decay level scheme for <sup>257</sup>Rf<sup>g,m</sup> from the studies reported in 2007 by Hessberger ''et al.'' at GSI<ref>{{cite journal |last1=Streicher |first1=B. |title=Alpha-gamma decay studies of 261Sg and 257Rf |journal=The European Physical Journal A |volume=45 |issue=3 |pages=275–286 |year=2010 |doi=10.1140/epja/i2010-11005-2 |bibcode = 2010EPJA...45..275S |last2=Heßberger |first2=F. P. |last3=Antalic |first3=S. |last4=Hofmann |first4=S. |last5=Ackermann |first5=D. |last6=Heinz |first6=S. |last7=Kindler |first7=B. |last8=Khuyagbaatar |first8=J. |last9=Kojouharov |first9=I. |display-authors=1 |last10=Kuusiniemi |first10=P. |last11=Leino |first11=M. |last12=Lommel |first12=B. |last13=Mann |first13=R. |last14=Šáro |first14=Š. |last15=Sulignano |first15=B. |last16=Uusitalo |first16=J. |last17=Venhart |first17=M. |s2cid=120939068 }}</ref>]]

Several early studies on the synthesis of <sup>263</sup>Rf have indicated that this nuclide decays primarily by spontaneous fission with a half-life of 10–20 minutes. More recently, a study of [[Chemistry:Hassium|hassium]] isotopes allowed the synthesis of atoms of <sup>263</sup>Rf decaying with a shorter half-life of 8 seconds. These two different decay modes must be associated with two isomeric states, but specific assignments are difficult due to the low number of observed events.<ref name="Rf263" />

During research on the synthesis of rutherfordium isotopes utilizing the <sup>244</sup>Pu(<sup>22</sup>Ne,5n)<sup>261</sup>Rf reaction, the product was found to undergo exclusive 8.28&nbsp;MeV alpha decay with a half-life of 78 seconds. Later studies at GSI on the synthesis of [[Chemistry:Copernicium|copernicium]] and hassium isotopes produced conflicting data, as <sup>261</sup>Rf produced in the decay chain was found to undergo 8.52&nbsp;MeV alpha decay with a half-life of 4 seconds. Later results indicated a predominant fission branch. These contradictions led to some doubt on the discovery of copernicium. The first isomer is currently denoted <sup>261a</sup>Rf (or simply <sup>261</sup>Rf) whilst the second is denoted <sup>261b</sup>Rf (or <sup>261m</sup>Rf). However, it is thought that the first nucleus belongs to a high-spin ground state and the latter to a low-spin metastable state.<ref name="Rf261ab">{{cite report|url=http://lch.web.psi.ch/files/anrep01/B-02heavies.pdf |title=Evidence for isomeric states in <sup>261</sup>Rf |last1=Dressler |first1=R. |last2=Türler |first2=A. |publisher=PSI Annual Report 2001 |access-date=2008-01-29 |url-status=dead |archive-url=https://web.archive.org/web/20110707001918/http://lch.web.psi.ch/files/anrep01/B-02heavies.pdf |archive-date=2011-07-07 }}</ref>
The discovery and confirmation of <sup>261b</sup>Rf provided proof for the discovery of copernicium in 1996.<ref>{{Cite journal |journal=Pure Appl. Chem. |year=2009 |title=Discovery of the element with atomic number 112 |format=IUPAC Technical Report |url=http://media.iupac.org/publications/pac/2003/pdf/7510x1601.pdf |doi=10.1351/PAC-REP-08-03-05 |volume=81 |issue=7 |page=1331 |last1=Barber |first1=R. C. |last2=Gaeggeler |first2=H. W. |last3=Karol |first3=P. J. |last4=Nakahara |first4=H. |last5=Vardaci |first5=E |last6=Vogt |first6=E.|s2cid=95703833 }}</ref>

A detailed spectroscopic study of the production of <sup>257</sup>Rf nuclei using the reaction <sup>208</sup>Pb(<sup>50</sup>Ti,n)<sup>257</sup>Rf allowed the identification of an isomeric level in <sup>257</sup>Rf. The work confirmed that <sup>257g</sup>Rf has a complex spectrum with 15 alpha lines. A level structure diagram was calculated for both isomers.<ref name="Rf257">{{cite journal |last1=Qian |first1=J. |title=Spectroscopy of Rf257 |journal=Physical Review C |volume=79 |issue=6 |page=064319 |year=2009 |doi=10.1103/PhysRevC.79.064319 |bibcode = 2009PhRvC..79f4319Q |last2=Heinz |first2=A. |last3=Khoo |first3=T. |last4=Janssens |first4=R. |last5=Peterson |first5=D. |last6=Seweryniak |first6=D. |last7=Ahmad |first7=I. |last8=Asai |first8=M. |last9=Back |first9=B. |display-authors=1 |last10=Carpenter |first10=M. |last11=Garnsworthy |first11=A. |last12=Greene |first12=J. |last13=Hecht |first13=A. |last14=Jiang |first14=C. |last15=Kondev |first15=F. |last16=Lauritsen |first16=T. |last17=Lister |first17=C. |last18=Robinson |first18=A. |last19=Savard |first19=G. |last20=Scott |first20=R. |last21=Vondrasek |first21=R. |last22=Wang |first22=X. |last23=Winkler |first23=R. |last24=Zhu |first24=S. }}</ref> Similar isomers were reported for <sup>256</sup>Rf also.<ref name="rf256">{{cite journal |author = Jeppesen |title = Multi-quasiparticle states in<sup>256</sup>Rf |doi =10.1103/PhysRevC.79.031303 |journal = Physical Review C |year=2009 |volume=79 |issue = 3 |page = 031303(R) |bibcode = 2009PhRvC..79c1303J |last2 = Dragojević |first2 = I. |last3 = Clark |first3 = R. |last4 = Gregorich |first4 = K. |last5 = Ali |first5 = M. |last6 = Allmond |first6 = J. |last7 = Beausang |first7 = C. |last8 = Bleuel |first8 = D. |last9 = Cromaz |first9 = M. |display-authors = 2 |last10 = Deleplanque |first10 = M. |last11 = Ellison |first11 = P. |last12 = Fallon |first12 = P. |last13 = Garcia |first13 = M. |last14 = Gates |first14 = J. |last15 = Greene |first15 = J. |last16 = Gros |first16 = S. |last17 = Lee |first17 = I. |last18 = Liu |first18 = H. |last19 = MacChiavelli |first19 = A. |last20 = Nelson |first20 = S. |last21 = Nitsche |first21 = H. |last22 = Pavan |first22 = J. |last23 = Stavsetra |first23 = L. |last24 = Stephens |first24 = F. |last25 = Wiedeking |first25 = M. |last26 = Wyss |first26 = R. |last27 = Xu |first27 = F. }}</ref>

== Chemical yields of isotopes ==

=== Cold fusion ===
The table below provides cross-sections and excitation energies for cold fusion reactions producing rutherfordium isotopes directly. Data in bold represents maxima derived from excitation function measurements. + represents an observed exit channel.

{| class="wikitable"
|-
! Projectile
! Target
! CN
! 1n
! 2n
! 3n
|-
| <sup>50</sup>Ti
| <sup>208</sup>Pb
| <sup>258</sup>Rf
| '''38.0&nbsp;nb, 17.0&nbsp;MeV'''
| '''12.3&nbsp;nb, 21.5&nbsp;MeV'''
| '''660&nbsp;pb, 29.0&nbsp;MeV'''
|-
| <sup>50</sup>Ti
| <sup>207</sup>Pb
| <sup>257</sup>Rf
| 4.8&nbsp;nb
| 
|
|-
| <sup>50</sup>Ti
| <sup>206</sup>Pb
| <sup>256</sup>Rf
| 800&nbsp;pb, 21.5&nbsp;MeV
| 2.4&nbsp;nb, 21.5&nbsp;MeV
|
|-
| <sup>50</sup>Ti
| <sup>204</sup>Pb
| <sup>254</sup>Rf
| 190&nbsp;pb, 15.6&nbsp;MeV
| 
|
|-
| <sup>48</sup>Ti
| <sup>208</sup>Pb
| <sup>256</sup>Rf
| '''380&nbsp;pb, 17.0&nbsp;MeV'''
|
| 
|}

=== Hot fusion ===
The table below provides cross-sections and excitation energies for hot fusion reactions producing rutherfordium isotopes directly. Data in bold represents maxima derived from excitation function measurements. + represents an observed exit channel.

{| class="wikitable"
|-
! Projectile
! Target
! CN
! 3n
! 4n
! 5n
|-
| <sup>26</sup>Mg
| <sup>238</sup>U
| <sup>264</sup>Rf
| 
| 240&nbsp;pb
| 1.1&nbsp;nb
|-
| <sup>22</sup>Ne
| <sup>244</sup>Pu
| <sup>266</sup>Rf
| 
| +
| 4.0&nbsp;nb
|-
| <sup>18</sup>O
| <sup>248</sup>Cm
| <sup>266</sup>Rf
| 
| +
| 13.0&nbsp;nb
|}

== References ==

{{reflist|30em}}
* Isotope masses from:
**{{cite journal |author=M. Wang |author2=G. Audi |author3=A. H. Wapstra |author4=F. G. Kondev |author5=M. MacCormick |author6=X. Xu|year=2012 |title=The AME2012 atomic mass evaluation (II). Tables, graphs and references. |url=http://amdc.in2p3.fr/masstables/Ame2012/Ame2012b-v2.pdf |journal=Chinese Physics C |volume=36 |issue= 12 |pages=1603–2014 |doi=10.1088/1674-1137/36/12/003|bibcode = 2012ChPhC..36....3M |hdl=11858/00-001M-0000-0010-23E8-5 |s2cid=250839471 |display-authors=0}}
**{{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}}

==External links==
*http://www.radiochemistry.org/periodictable/elements/isotopes_data/104.html
*http://www-phynu.cea.fr/science_en_ligne/carte_potentiels_microscopiques/choix/isotopes/z104_eng.html
*http://www.springermaterials.com/docs/info/978-3-540-70609-0_7730.html
{{Navbox element isotopes}}

[[Category:Isotopes of rutherfordium| ]]
[[Category:Lists of isotopes by element|Rutherfordium]]

{{Sourceattribution|Isotopes of rutherfordium}}