Editing Tennessine (section)

=== Nuclear stability and isotopes ===
{{main|Isotopes of tennessine}}
{{see also|Island of stability}}

The stability of nuclei quickly decreases with the increase in atomic number after [[curium]], element&nbsp;96, whose half-life is four orders of magnitude longer than that of any subsequent element. All isotopes with an atomic number above [[mendelevium|101]] undergo radioactive decay with half-lives of less than 30 hours. No elements with atomic numbers above 82 (after [[lead]]) have stable isotopes.<ref>{{cite journal |last1=de Marcillac |first1=P. |last2=Coron |first2=N. |last3=Dambier |first3=G. |last4=Leblanc |first4=J. |last5=Moalic |first5=J.-P. |display-authors=3 |date=2003 |title=Experimental detection of α-particles from the radioactive decay of natural bismuth |s2cid-access=free |url=http://web.mit.edu/8.13/8.13c/references-fall/alphadecay/marcillac-bi209-alpha-decay-nature-2003.pdf |via=MIT |journal=Nature |volume=422 |pages=876–878 |pmid=12712201 |doi=10.1038/nature01541 |issue=6934 |bibcode=2003Natur.422..876D |s2cid=4415582 |url-status=live |archive-url=https://web.archive.org/web/20221211103340/http://web.mit.edu/8.13/8.13c/references-fall/alphadecay/marcillac-bi209-alpha-decay-nature-2003.pdf |archive-date= Dec 11, 2022 }}</ref> This is because of the ever-increasing Coulomb repulsion of protons, so that the [[strong nuclear force]] cannot hold the nucleus together against [[spontaneous fission]] for long. Calculations suggest that in the absence of other stabilizing factors, elements with more than [[rutherfordium|104 protons]] should not exist.<ref name="liquiddrop">{{cite journal |last=Möller |first=P. |date=2016 |title=The limits of the nuclear chart set by fission and alpha decay |journal=EPJ Web of Conferences |volume=131 |pages=03002:1–8 |url=https://inspirehep.net/record/1502715/files/epjconf-NS160-03002.pdf |via=INSPIRE |doi=10.1051/epjconf/201613103002 |bibcode=2016EPJWC.13103002M|doi-access=free |bibcode-access=free |url-status=live |archive-url=https://web.archive.org/web/20250122114150/https://www.epj-conferences.org/articles/epjconf/pdf/2016/26/epjconf-NS160-03002.pdf |archive-date= Jan 22, 2025 }}</ref> However, researchers in the 1960s suggested that the closed [[nuclear shell model|nuclear shells]] around 114&nbsp;protons and 184&nbsp;neutrons should counteract this instability, creating an "[[island of stability]]" where nuclides could have half-lives reaching thousands or millions of years. While scientists have still not reached the island, the mere existence of the [[superheavy element]]s (including tennessine) confirms that this stabilizing effect is real, and in general the known superheavy nuclides become exponentially longer-lived as they approach the predicted location of the island.<ref>{{cite book |title=Van&nbsp;Nostrand's scientific encyclopedia |first1=G.D. |last1=Considine |first2=Peter H. |last2=Kulik |publisher=Wiley-Interscience |date=2002 |edition=9th |isbn=978-0-471-33230-5 |oclc=223349096 }}</ref><ref name="retro">{{cite journal |last1=Oganessian |first1=Yu. Ts. |last2=Sobiczewski |first2=A. |last3=Ter-Akopian |first3=G. M. |date=9 January 2017 |title=Superheavy nuclei: from predictions to discovery |journal=Physica Scripta |volume=92 |issue=2 |pages=023003–1–21 |doi=10.1088/1402-4896/aa53c1 |bibcode=2017PhyS...92b3003O |s2cid=125713877 }}</ref> Tennessine is the second-heaviest element created so far, and all its known isotopes have half-lives of less than one second. Nevertheless, this is longer than the values predicted prior to their discovery: the predicted lifetimes for <sup>293</sup>Ts and <sup>294</sup>Ts used in the discovery paper were 10&nbsp;ms and 45&nbsp;ms respectively, while the observed lifetimes were 21&nbsp;ms and 112&nbsp;ms respectively.<ref name="117s" /> The Dubna team believes that the synthesis of the element is direct experimental proof of the existence of the island of stability.<ref name="IS" />

[[File:Island of Stability derived from Zagrebaev.svg|center|thumb|upright=3.0|alt=A 2D graph with rectangular cells colored in black-and-white colors, spanning from the llc to the urc, with cells mostly becoming lighter closer to the latter|A chart of nuclide stability as used by the Dubna team in 2010. Characterized isotopes are shown with borders. According to the discoverers, the synthesis of element 117 serves as definite proof of the existence of the "island of stability" (circled).<ref name="IS">{{cite web |title=Element 117 is synthesized |url=https://www.jinr.ru/news_article.asp?n_id=539& |date=2010 |publisher=JINR |access-date=2015-06-28 }}</ref>]]

It has been calculated that the isotope <sup>295</sup>Ts would have a half-life of about 18&nbsp;[[millisecond]]s, and it may be possible to produce this isotope via the same berkelium–calcium reaction used in the discoveries of the known isotopes, <sup>293</sup>Ts and <sup>294</sup>Ts. The chance of this reaction producing <sup>295</sup>Ts is estimated to be, at most, one-seventh the chance of producing <sup>294</sup>Ts.{{sfn|Zagrebaev|Karpov|Greiner|2013|page=3}}<ref name="FengE117">{{cite journal |arxiv=0708.0159 |doi=10.1088/0256-307X/24/9/024 |title=Possible Way to Synthesize Superheavy Element ''Z'' = 117 |date=2007 |last1=Zhao-Qing |first1=F. |journal=Chinese Physics Letters |volume=24 |page=2551 |last2=Gen-Ming |first2=Jin |last3=Ming-Hui |first3=Huang |last4=Zai-Guo |first4=Gan |last5=Nan |first5=Wang |last6=Jun-Qing |first6=Li |issue=9 |bibcode = 2007ChPhL..24.2551F |s2cid=8778306 |display-authors=3 }}</ref><ref name="FengHotFusion">{{cite journal |arxiv=0803.1117 |doi=10.1016/j.nuclphysa.2008.11.003 |title=Production of heavy and superheavy nuclei in massive fusion reactions |date=2009 |first1=F. |last1=Zhao-Qing |journal=Nuclear Physics A |volume=816 |issue=1–4 |page=33 |last2=Jina |first2=Gen-Ming |last3=Li |first3= Jun-Qing |last4=Scheid |first4=Werner |display-authors=3 |bibcode=2009NuPhA.816...33F |s2cid=18647291 }}</ref> This isotope could also be produced in a pxn channel of the <sup>249</sup>Cf+<sup>48</sup>Ca reaction that successfully produced oganesson, evaporating a proton alongside some neutrons; the heavier tennessine isotopes <sup>296</sup>Ts and <sup>297</sup>Ts could similarly be produced in the <sup>251</sup>Cf+<sup>48</sup>Ca reaction.<ref name=Yerevan2023PPT>{{cite conference |url=https://indico.jinr.ru/event/3622/contributions/20021/attachments/15292/25806/Yerevan2023.pdf |title=Interesting fusion reactions in superheavy region |first1=J. |last1=Hong |first2=G. G. |last2=Adamian |first3=N. V. |last3=Antonenko |first4=P. |last4=Jachimowicz |first5=M. |last5=Kowal |conference=IUPAP Conference "Heaviest nuclei and atoms" |publisher=Joint Institute for Nuclear Research |date=26 April 2023 |access-date=30 July 2023}}</ref><ref name=pxn>{{cite journal |last1=Hong |first1=J. |last2=Adamian |first2=G. G. |last3=Antonenko |first3=N. V. |date=2017 |title=Ways to produce new superheavy isotopes with ''Z''&nbsp;=&nbsp;111–117 in charged particle evaporation channels |journal=Physics Letters B |volume=764 |pages=42–48 |doi=10.1016/j.physletb.2016.11.002 |bibcode=2017PhLB..764...42H|doi-access=free }}</ref> Calculations using a [[quantum tunneling]] model predict the existence of several isotopes of tennessine up to <sup>303</sup>Ts. The most stable of these is expected to be <sup>296</sup>Ts with an alpha-decay half-life of 40&nbsp;milliseconds.<ref name="prc08ADNDT08">{{cite journal |journal=Physical Review C |volume=77 |page=044603 |date=2008 |title=Search for long lived heaviest nuclei beyond the valley of stability |first1=R. P. |last1=Chowdhury |first2=C. |last2=Samanta |first3=D. N. |last3=Basu |doi=10.1103/PhysRevC.77.044603 |bibcode=2008PhRvC..77d4603C |issue=4 |arxiv=0802.3837 |s2cid=119207807 }}</ref> A [[Semi-empirical mass formula#The liquid drop model and its analysis|liquid drop model]] study on the element's isotopes shows similar results; it suggests a general trend of increasing stability for isotopes heavier than <sup>301</sup>Ts, with [[partial half-life|partial half-lives]] exceeding the [[age of the universe]] for the heaviest isotopes like <sup>335</sup>Ts when beta decay is not considered.<ref name="Brazil">{{cite journal |last1=Duarte |first1=S. B. |last2=Tavares |first2=O. A. P. |last3=Gonçalves |first3=M. |last4=Rodríguez |first4=O. |last5=Gúzman |first5=F. |last6=Barbosa |first6=T. N. |last7=García |first7=F. |last8=Dimarco |first8=A. |display-authors=3 |title=Half-life prediction for decay modes for superheavy nuclei |journal=Journal of Physics G: Nuclear and Particle Physics |series=Notas de Física |number=CBPF-NF-022/04 |publisher=Centro Brasileiro de Pesquisas Físicas |date=September 2004 |volume=30 |pages=1487–1494 |issn=0029-3865 |url=https://www.iaea.org/inis/collection/NCLCollectionStore/_Public/36/073/36073846.pdf |doi=10.1088/0954-3899/30/10/014|bibcode=2004JPhG...30.1487D }}</ref> Lighter isotopes of tennessine may be produced in the <sup>243</sup>Am+<sup>50</sup>Ti reaction, which was considered as a contingency plan by the Dubna team in 2008 if <sup>249</sup>Bk proved unavailable;<ref>{{cite web |url=https://nuclphys.sinp.msu.ru/nseminar/12.02.08.pdf |title=Синтез новых элементов 113-118 в реакциях полного слияния <sup>48</sup>Ca + <sup>238</sup>U-<sup>249</sup>Cf |trans-title=Synthesis of new elements 113–118 in complete fusion reactions <sup>48</sup>Ca + <sup>238</sup>U–<sup>249</sup>Cf |last=Utyonkov |first=V. K. |date=12 February 2008 |website=nuclphys.sinp.msu.ru |access-date=28 April 2017 |archive-date=1 October 2016 |archive-url=https://web.archive.org/web/20161001224516/http://nuclphys.sinp.msu.ru/nseminar/12.02.08.pdf |url-status=dead }}</ref> the isotopes <sup>289</sup>Ts through <sup>292</sup>Ts could also be produced as daughters of [[ununennium|element 119]] isotopes that can be produced in the <sup>243</sup>Am+<sup>54</sup>Cr and <sup>249</sup>Bk+<sup>50</sup>Ti reactions.<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>
{{Clear}}