Editing Seaborgium (section)

==Isotopes==
{{main|Isotopes of seaborgium}}
{{Isotopes summary
|element=seaborgium
|isotopes=
{{isotopes summary/isotope
|mn=258|sym=Sg|hl={{sort|3|2.7 ms}}|ref={{NUBASE2020|ref}}
|dm=SF |year=1994|re=<sup>209</sup>Bi(<sup>51</sup>V,2n)
}}
{{isotopes summary/isotope
|mn=259|sym=Sg|hl={{sort|402|402 ms}}|ref={{NUBASE2020|ref}}
|dm=α |year=1985|re=<sup>207</sup>Pb(<sup>54</sup>Cr,2n)
}}
{{isotopes summary/isotope
|mn=259m|sym=Sg|hl={{sort|226|226 ms}}|ref={{NUBASE2020|ref}}
|dm=α, SF |year=2015|re=<sup>206</sup>Pb(<sup>54</sup>Cr,n)<ref>{{cite journal |last1=Antalic |first1=S. |last2=Heßberger |first2=F. P. |last3=Ackermann |first3=D. |last4=Heinz |first4=S. |last5=Hofmann |first5=S. |last6=Kindler |first6=B. |last7=Khuyagbaatar |first7=J. |last8=Lommel |first8=B. |last9=Mann |first9=R. |title=Nuclear isomers in <sup>259</sup>Sg and <sup>255</sup>Rf |journal=The European Physical Journal A |date=14 April 2015 |volume=51 |issue=4 |pages=41 |doi=10.1140/epja/i2015-15041-0 |bibcode=2015EPJA...51...41A |s2cid=254117522 |url=https://link.springer.com/article/10.1140/epja/i2015-15041-0 |access-date=2 July 2023 |language=en |issn=1434-601X |archive-date=8 February 2024 |archive-url=https://web.archive.org/web/20240208143027/https://link.springer.com/article/10.1140/epja/i2015-15041-0 |url-status=live }}</ref>
}}
{{isotopes summary/isotope
|mn=260|sym=Sg|hl={{sort|5|4.95 ms}}|ref={{NUBASE2020|ref}}
|dm=SF, α |year=1985|re=<sup>208</sup>Pb(<sup>54</sup>Cr,2n)
}}
{{isotopes summary/isotope
|mn=261|sym=Sg|hl={{sort|183|183 ms}}|ref={{NUBASE2020|ref}}
|dm=α, β<sup>+</sup>, SF |year=1985|re=<sup>208</sup>Pb(<sup>54</sup>Cr,n)
}}
{{isotopes summary/isotope
|mn=261m|sym=Sg|hl={{sort|0|9.3 μs}}|ref={{NUBASE2020|ref}}
|dm=IT |year=2009|re=<sup>208</sup>Pb(<sup>54</sup>Cr,n)
}}
{{isotopes summary/isotope
|mn=262|sym=Sg|hl={{sort|10|10.3 ms}}|ref={{NUBASE2020|ref}}
|dm=SF, α |year=2001|re=<sup>270</sup>Ds(—,2α)
}}
{{isotopes summary/isotope
|mn=263|sym=Sg|hl={{sort|940|940 ms}}|ref={{NUBASE2020|ref}}
|dm=α, SF |year=1994|re=<sup>271</sup>Ds(—,2α)
}}
{{isotopes summary/isotope
|mn=263m|sym=Sg|hl={{sort|420|420 ms}}|ref={{NUBASE2020|ref}}
|dm=α |year=1974|re=<sup>249</sup>Cf(<sup>18</sup>O,4n)
}}
{{isotopes summary/isotope
|mn=264|sym=Sg|hl={{sort|78|78 ms}}|ref={{NUBASE2020|ref}}
|dm=SF |year=2006|re=<sup>238</sup>U(<sup>30</sup>Si,4n)
}}
{{isotopes summary/isotope
|mn=265|sym=Sg|hl={{sort|9200|9.2 s}}|ref={{NUBASE2020|ref}}
|dm=α |year=1993|re=<sup>248</sup>Cm(<sup>22</sup>Ne,5n)
}}
{{isotopes summary/isotope
|mn=265m|sym=Sg|hl={{sort|16400|16.4 s}}|ref={{NUBASE2020|ref}}
|dm=α |year=1993|re=<sup>248</sup>Cm(<sup>22</sup>Ne,5n)
}}
{{isotopes summary/isotope
|mn=266|sym=Sg|hl={{sort|390|390 ms}}|ref={{NUBASE2020|ref}}
|dm=SF |year=2004|re=<sup>270</sup>Hs(—,α)
}}
{{isotopes summary/isotope
|mn=267|sym=Sg|hl={{sort|590000|9.8 min}}|ref=<ref>{{cite journal |last1=Oganessian |first1=Yu. Ts. |last2=Utyonkov |first2=V. K. |last3=Shumeiko |first3=M. V. |last4=Abdullin |first4=F. Sh. |last5=Adamian |first5=G. G. |last6=Dmitriev |first6=S. N. |last7=Ibadullayev |first7=D. |last8=Itkis |first8=M. G. |last9=Kovrizhnykh |first9=N. D. |last10=Kuznetsov |first10=D. A. |last11=Petrushkin |first11=O. V. |last12=Podshibiakin |first12=A. V. |last13=Polyakov |first13=A. N. |last14=Popeko |first14=A. G. |last15=Rogov |first15=I. S. |last16=Sagaidak |first16=R. N. |last17=Schlattauer |first17=L. |last18=Shubin |first18=V. D. |last19=Solovyev |first19=D. I. |last20=Tsyganov |first20=Yu. S. |last21=Voinov |first21=A. A. |last22=Subbotin |first22=V. G. |last23=Bublikova |first23=N. S. |last24=Voronyuk |first24=M. G. |last25=Sabelnikov |first25=A. V. |last26=Bodrov |first26=A. Yu. |last27=Aksenov |first27=N. V. |last28=Khalkin |first28=A. V. |last29=Gan |first29=Z. G. |last30=Zhang |first30=Z. Y. |last31=Huang |first31=M. H. |last32=Yang |first32=H. B. |display-authors=3 |title=Synthesis and decay properties of isotopes of element 110: Ds 273 and Ds 275 |journal=Physical Review C |date=6 May 2024 |volume=109 |issue=5 |page=054307 |doi=10.1103/PhysRevC.109.054307 |url=https://journals.aps.org/prc/pdf/10.1103/PhysRevC.109.054307 |access-date=11 May 2024 |language=en |issn=2469-9985 |bibcode=2024PhRvC.109e4307O}}</ref>
|dm=α |year=2004|re=<sup>271</sup>Hs(—,α)
}}
{{isotopes summary/isotope
|mn=267m|sym=Sg|hl={{sort|100000|1.7 min}}|ref=<ref name="Ds2024" />
|dm=SF |year=2024|re=<sup>271</sup>Hs(—,α)
}}
{{isotopes summary/isotope
|mn=268|sym=Sg|hl={{sort|13000|13 s}}|ref=<ref name="276Ds-2023" />
|dm=SF |year=2022|re=<sup>276</sup>Ds(—,2α)
}}
{{isotopes summary/isotope
|mn=269|sym=Sg|hl={{sort|300000|5 min}}|ref={{NUBASE2020|ref}}<ref name=jinr2024>{{Cite web |url=https://indico.jinr.ru/event/4343/contributions/28663/attachments/20748/36083/U%20+%20Cr%20AYSS%202024.pptx |title=Synthesis and study of the decay properties of isotopes of superheavy element Lv in Reactions <sup>238</sup>U + <sup>54</sup>Cr and <sup>242</sup>Pu + <sup>50</sup>Ti |last=Ibadullayev |first=Dastan |date=2024 |website=jinr.ru |publisher=[[Joint Institute for Nuclear Research]] |access-date=2 November 2024 |quote=}}</ref>
|dm=α, SF |year=2010|re=<sup>285</sup>Fl(—,4α)
}}
{{isotopes summary/isotope
|mn=271|sym=Sg|hl={{sort|31000|31 s}}|ref=<ref name=PuCa2022/>
|dm=α, SF |year=2003|re=<sup>287</sup>Fl(—,4α)
}}
}}

[[Superheavy element]]s such as seaborgium are produced by bombarding lighter elements in [[particle accelerator]]s that induces [[fusion reaction]]s. Whereas most of the isotopes of seaborgium can be synthesized directly this way, some heavier ones have only been observed as decay products of elements with higher [[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, fusion reactions that generate superheavy elements are separated into "hot" and "cold". In hot fusion reactions, very light, high-energy projectiles are accelerated toward very heavy targets ([[actinide]]s), giving rise to compound nuclei at high excitation energy (~40–50&nbsp;[[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 [[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 [[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>

Seaborgium has no stable or naturally occurring isotopes. Several radioactive isotopes have been synthesized in the laboratory, either by fusing two atoms or by observing the decay of heavier elements. Thirteen different isotopes of seaborgium have been reported with mass numbers 258–269 and 271, four of which, seaborgium-261, −263, −265, and −267, have known [[metastable state]]s. All of these decay only through alpha decay and spontaneous fission, with the single exception of seaborgium-261 that can also undergo [[electron capture]] to dubnium-261.<ref name="nuclidetable" />

There is a trend toward increasing half-lives for the heavier isotopes, though [[even and odd atomic nuclei#Even proton, odd neutron|even–odd]] isotopes are generally more stable than their neighboring [[even and odd atomic nuclei#Even proton, even neutron|even–even]] isotopes, because the odd neutron leads to increased hindrance of spontaneous fission;<ref name=SFparity>{{cite journal |doi=10.1140/epja/s10050-022-00896-3 |last=Khuyagbaatar |first=J. |date=2022 |title=Fission-stability of high-K states in superheavy nuclei |journal=The European Physical Journal A |volume=58 |issue=243|page=243 |bibcode=2022EPJA...58..243K |s2cid=254658975 |doi-access=free }}</ref> among known seaborgium isotopes, alpha decay is the predominant decay mode in even–odd nuclei whereas fission dominates in [[Even-even nucleus|even–even nuclei]]. Three of the heaviest known isotopes, <sup>267</sup>Sg, <sup>269</sup>Sg, and <sup>271</sup>Sg, are also the longest-lived, having half-lives on the order of several minutes.<ref name="nuclidetable">{{cite web |url=http://www.nndc.bnl.gov/chart/reCenter.jsp?z=107&n=163 |title=Interactive Chart of Nuclides |publisher=Brookhaven National Laboratory |author=Sonzogni, Alejandro |location=National Nuclear Data Center |access-date=2008-06-06 |archive-date=2018-06-12 |archive-url=https://web.archive.org/web/20180612141714/http://www.nndc.bnl.gov/chart/reCenter.jsp?z=107&n=163 |url-status=dead }}</ref> Some other isotopes in this region are predicted to have comparable or even longer half-lives. Additionally, <sup>263</sup>Sg, <sup>265</sup>Sg, <sup>265m</sup>Sg, and <sup>268</sup>Sg<ref name="276Ds-2023"/> have half-lives measured in seconds. All the remaining isotopes have half-lives measured in milliseconds, with the exception of the shortest-lived isotope, <sup>261m</sup>Sg, with a half-life of only 9.3&nbsp;microseconds.{{NUBASE2020|ref}}

The proton-rich isotopes from <sup>258</sup>Sg to <sup>261</sup>Sg were directly produced by cold fusion; all heavier isotopes were produced from the repeated alpha decay of the heavier elements [[hassium]], [[darmstadtium]], and [[flerovium]], with the exceptions of the isotopes <sup>263m</sup>Sg, <sup>264</sup>Sg, <sup>265</sup>Sg, and <sup>265m</sup>Sg, which were directly produced by hot fusion through irradiation of actinide targets.