Editing Hassium (section)

== Isotopes ==
{{Main|Isotopes of hassium}}
{{Isotopes summary
|element=hassium
|other_notes={{efn|Few nuclei of each hassium isotope have been synthesized, and thus half-lives of these isotopes cannot be determined very precisely. Therefore, a half-life may be given as the most likely value alongside a confidence interval that corresponds to one standard deviation (such an interval based on future experiments, whose result is yet unknown, contains the true value with a probability of ~68.3%): for example, the value of 1.42{{spaces}}s in the isotope table obtained for <sup>268</sup>Hs was listed in the source as 1.42{{spaces}}±1.13{{spaces}}s, and this value is a modification of the value of {{nowrap|0.38{{su|p=+1.8|b=−0.17}} s}}.{{sfn|Audi et al.|2017|p=030001-134}}}}
|year_ref={{sfn|Audi et al.|2017|p=030001-133}}
|reaction_ref=<ref name="thoennessen2016">{{Thoennessen2016|pages=229, 234, 238}}</ref>{{efn|The notation <sup>208</sup>Pb(<sup>56</sup>Fe,n)<sup>263</sup>Hs denotes a nuclear reaction between a nucleus of <sup>208</sup>Pb that was bombarded with a nucleus of <sup>56</sup>Fe; the two fused, and after a single neutron had been emitted, the remaining nucleus was <sup>263</sup>Hs. Another notation for this reaction would be <sup>208</sup>Pb + <sup>56</sup>Fe → <sup>263</sup>Hs + n.}}
|isotopes=
{{isotopes summary/isotope
|mn=263 |sym=Hs |hl={{sort|760|760 μs}}|ref={{sfn|Audi et al.|2017|p=030001-133}}
|dm=α, SF |year=2009|re=<sup>208</sup>Pb(<sup>56</sup>Fe,n)
}}
{{isotopes summary/isotope
|mn=264|sym=Hs|hl={{sort|540|540 μs}}|ref={{sfn|Audi et al.|2017|p=030001-133}}|dm=α, SF|year=1986|re=<sup>207</sup>Pb(<sup>58</sup>Fe,n)
}}
{{isotopes summary/isotope
|mn=265|sym=Hs|hl={{sort|1960|1.96 ms}}|ref={{sfn|Audi et al.|2017|p=030001-133}}|dm=α, SF|year=1984|re=<sup>208</sup>Pb(<sup>58</sup>Fe,n)
}}
{{isotopes summary/isotope
|mn=265m|sym=Hs|hl={{sort|360|360 μs}}|ref={{sfn|Audi et al.|2017|p=030001-133}}|dm=α|year=1995|re=<sup>208</sup>Pb(<sup>58</sup>Fe,n)
}}
{{isotopes summary/isotope
|mn=266|sym=Hs|hl={{sort|3020|3.02 ms}}|ref={{sfn|Audi et al.|2017|p=030001-133}}|dm=α, SF|year=2001|re=<sup>270</sup>Ds(—,α)
}}
{{isotopes summary/isotope
|mn=266m|sym=Hs|hl={{sort|280000|280 ms}}|ref={{sfn|Audi et al.|2017|p=030001-133}}|dm=α|year=2011|re=<sup>270m</sup>Ds(—,α)
}}
{{isotopes summary/isotope
|mn=267|sym=Hs|hl={{sort|55000|55 ms}}|ref={{sfn|Audi et al.|2017|p=030001-134}}|dm=α|year=1995|re=<sup>238</sup>U(<sup>34</sup>S,5n)
}}
{{isotopes summary/isotope
|mn=267m|sym=Hs|hl={{sort|990|990 μs}}|ref={{sfn|Audi et al.|2017|p=030001-134}}|dm=α|year=2004|re=<sup>238</sup>U(<sup>34</sup>S,5n)
}}
{{isotopes summary/isotope
|mn=268|sym=Hs|hl={{sort|1420000|1.42 s}}|ref={{sfn|Audi et al.|2017|p=030001-134}}|dm=α|year=2010|re=<sup>238</sup>U(<sup>34</sup>S,4n)
}}
{{isotopes summary/isotope
|mn=269|sym=Hs|hl={{sort|13000000|13 s}}|ref=<ref name=Ds2024/>|dm=α|year=1996|re=<sup>277</sup>Cn(—,2α)
}}
{{isotopes summary/isotope
|mn=269m|sym=Hs|hl={{sort|2800000|2.8 s}}|ref=<ref name=Ds2024/>|dm=α, [[Isomeric transition|IT]]|year=2024|re=<sup>273</sup>Ds(—,α)
}}
{{isotopes summary/isotope
|mn=270|sym=Hs|hl={{sort|7600000|7.6 s}}|ref={{sfn|Audi et al.|2017|p=030001-134}}|dm=α|year=2003|re=<sup>248</sup>Cm(<sup>26</sup>Mg,4n)
}}
{{isotopes summary/isotope
|mn=271|sym=Hs|hl={{sort|46000000|46 s}}|ref=<ref name=Ds2024>{{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=2008|re=<sup>248</sup>Cm(<sup>26</sup>Mg,3n)
}}
{{isotopes summary/isotope
|mn=271m|sym=Hs|hl={{sort|7100000|7.1 s}}|ref=<ref name=Ds2024/>|dm=α, IT|year=2024|re=<sup>275</sup>Ds(—,α)
}}
{{isotopes summary/isotope
|mn=272|sym=Hs|hl={{sort|160000|160 ms}}|ref=<ref name="276Ds-2023">{{cite journal |title=New isotope <sup>276</sup>Ds and its decay products <sup>272</sup>Hs and <sup>268</sup>Sg from the <sup>232</sup>Th + <sup>48</sup>Ca reaction |last1=Oganessian |first1=Yu. Ts. |last2=Utyonkov |first2=V. K. |last3=Shumeiko |first3=M. V. |display-authors=et al. |date=2023 |journal=Physical Review C |volume=108 |number=24611 |page=024611 |doi=10.1103/PhysRevC.108.024611|bibcode=2023PhRvC.108b4611O |s2cid=261170871 }}</ref>|dm=α|year=2022|re=<sup>276</sup>Ds(—,α)
}}
{{isotopes summary/isotope
|mn=273|sym=Hs|hl={{sort|510000|510 ms}}|ref=<ref name="PuCa2017">{{cite journal |last1=Utyonkov |first1=V. K. |last2=Brewer |first2=N. T. |first3=Yu. Ts. |last3=Oganessian |display-authors=3 |first4=K. P. |last4=Rykaczewski |first5=F. Sh. |last5=Abdullin |first6=S. N. |last6=Dimitriev |first7=R. K. |last7=Grzywacz |first8=M. G. |last8=Itkis |first9=K. |last9=Miernik |first10=A. N. |last10=Polyakov |first11=J. B. |last11=Roberto |first12=R. N. |last12=Sagaidak |first13=I. V. |last13=Shirokovsky |first14=M. V. |last14=Shumeiko |first15=Yu. S. |last15=Tsyganov |first16=A. A. |last16=Voinov |first17=V. G. |last17=Subbotin |first18=A. M. |last18=Sukhov |first19=A. V. |last19=Karpov |first20=A. G. |last20=Popeko |first21=A. V. |last21=Sabel'nikov |first22=A. I. |last22=Svirikhin |first23=G. K. |last23=Vostokin |first24=J. H. |last24=Hamilton |first25=N. D. |last25=Kovrinzhykh |first26=L. |last26=Schlattauer |first27=M. A. |last27=Stoyer |first28=Z. |last28=Gan |first29=W. X. |last29=Huang |first30=L. |last30=Ma |date=30 January 2018 |title=Neutron-deficient superheavy nuclei obtained in the <sup>240</sup>Pu+<sup>48</sup>Ca reaction |journal=Physical Review C |volume=97 |issue=14320 |pages=014320 |doi=10.1103/PhysRevC.97.014320|bibcode=2018PhRvC..97a4320U |doi-access=free }}</ref>|dm=α|year=2010|re=<sup>285</sup>Fl(—,3α)
}}
{{isotopes summary/isotope
|mn=275|sym=Hs|hl={{sort|600000|600 ms}}|ref=<ref name=PuCa2022>{{cite journal |title=Investigation of <sup>48</sup>Ca-induced reactions with <sup>242</sup>Pu and <sup>238</sup>U targets at the JINR Superheavy Element Factory |journal=Physical Review C |volume=106 |number=24612 |year=2022 |first1=Yu. Ts. |last1=Oganessian |first2=V. K. |last2=Utyonkov |first3=D. |last3=Ibadullayev |page=024612 |display-authors=et al. |doi= 10.1103/PhysRevC.106.024612|bibcode=2022PhRvC.106b4612O |osti=1883808 |s2cid=251759318 }}</ref>|dm=α|year=2004|re=<sup>287</sup>Fl(—,3α)
}}
{{isotopes summary/isotope
|mn=277|sym=Hs|hl={{sort|12000|12 ms}}|ref={{sfn|Audi et al.|2017|p=030001-136}}|dm=α|year=2010|re=<sup>289</sup>Fl(—,3α)
}}
{{isotopes summary/isotope
|mn=277m|sym=Hs|hl={{sort|130000000|130 s}}{{efn|name=unconfirmed|Only one event of decay of this isotope has been registered.}}|ref={{sfn|Audi et al.|2017|p=030001-136}}<ref>{{NUBASE2020}}</ref>|dm=SF|year=2012|re=<sup>293m</sup>Lv(—,4α)
}}
}}

Hassium has no stable or naturally occurring isotopes. Several radioisotopes have been synthesized in the lab, either by fusing two atoms or by observing the decay of heavier elements. As of 2019, the quantity of all hassium ever produced was on the order of hundreds of atoms.<ref>{{Cite book |last=Scerri|first=E.|title=The Periodic Table: Its Story and Its Significance|publisher=[[Oxford University Press]] |url=https://books.google.com/books?id=tSa3DwAAQBAJ&q=hassium+100+atoms+scerri&pg=PA360 |date=2019|isbn=978-0-19-091438-7|author-link=Eric Scerri}}</ref><ref>{{Cite web|last=Helmenstine|first=A. M.|date=2019|title=Hassium Facts—Hs or Element 108 |url=https://www.thoughtco.com/hassium-facts-4136901|url-status=dead|archive-url=https://web.archive.org/web/20200801143047/https://www.thoughtco.com/hassium-facts-4136901|archive-date=1 August 2020|access-date=2020-07-09|website=[[ThoughtCo]]}}</ref> Thirteen isotopes with mass numbers 263 through 277 (except for 274 and 276) have been reported, six of which—{{sup|265, 266, 267, 269, 271, 277}}Hs—have known [[metastable state]]s,{{sfn|Audi et al.|2017|pp=030001-133–030001-136}}{{efn|Metastable nuclides are denoted by the letter "m" immediately the mass number, such as in "hassium-277m" aka {{sup|277m}}Hs.}} though that of {{sup|277}}Hs is unconfirmed.<ref name="gsi122">{{cite journal|last1=Hofmann|first1=S.|last2=Heinz|first2=S.|last3=Mann|first3=R.|last4=Maurer|first4=J. |last5=Khuyagbaatar|first5=J.|last6=Ackermann|first6=D.|last7=Antalic|first7=S.|last8=Barth|first8=W. |last9=Block|first9=M. |last10=Burkhard|first10=H. G.|last11=Comas|first11=V. F.|display-authors=3 |last12=Dahl|first12=L.|last13=Eberhardt|first13=K.|last14=Gostic|first14=J.|last15=Henderson|first15=R. A. |last16=Heredia|first16=J. A.|last17=Heßberger |first17=F. P.|last18=Kenneally|first18=J. M.|last19=Kindler |first19=B.|last20=Kojouharov|first20=I.|last21=Kratz|first21=J. V.|last22=Lang|first22=R.|last23=Leino |first23=M. |year=2012|title=The reaction <sup>48</sup>Ca + <sup>248</sup>Cm → <sup>296</sup>116<sup>*</sup> studied at the GSI-SHIP|journal=[[The European Physical Journal A]]|volume=48|issue=5|pages=62 |bibcode=2012EPJA...48...62H|doi=10.1140/epja/i2012-12062-1|last24=Lommel|first24=B. |last25=Moody |first25=K. J.|last26=Münzenberg|first26=G.|last27=Nelson|first27=S. L.|last28=Nishio|first28=K. |last29=Popeko|first29=A. G.|last30=Runke|first30=J.|s2cid=121930293}}</ref> Most of these isotopes decay mainly through alpha decay; this is the most common for all isotopes for which comprehensive decay characteristics are available; the only exception is {{sup|277}}Hs, which undergoes spontaneous fission.{{sfn|Audi et al.|2017|pp=030001-133–030001-136}} Lighter isotopes were usually synthesized by direct fusion of two nuclei, whereas heavier isotopes were typically observed as decay products of nuclei with larger atomic numbers.<ref name="thoennessen2016" />

Atomic nuclei have well-established nuclear shells, which make nuclei more stable. If a nucleus has certain numbers (magic numbers) of protons or neutrons, that complete a nuclear shell, then the nucleus is even more stable against decay. The highest known magic numbers are 82 for protons and 126 for neutrons. This notion is sometimes expanded to include additional numbers between those magic numbers, which also provide some additional stability and indicate closure of "sub-shells". Unlike the better-known lighter nuclei, superheavy nuclei are deformed. Until the 1960s, the [[liquid drop model]] was the dominant explanation for nuclear structure. It suggested that the [[fission barrier]] would disappear for nuclei with ~280{{spaces}}nucleons.<ref name="BrusselsSF">{{Cite web|last=Pauli|first=N.|date=2019|title=Nuclear fission|url=http://metronu.ulb.ac.be/npauly/Pauly/physnu/chapter_8.pdf|access-date=2020-02-16|work=Introductory Nuclear, Atomic and Molecular Physics (Nuclear Physics Part)|publisher=[[Université libre de Bruxelles]]|archive-date=21 October 2021|archive-url=https://web.archive.org/web/20211021225818/http://metronu.ulb.ac.be/npauly/Pauly/physnu/chapter_8.pdf|url-status=live}}</ref><ref name="Oganessian042">{{Cite journal|last=Oganessian|first=Yu. Ts.|date=2004|title=Superheavy elements|journal=Pure and Applied Chemistry|volume=76|issue=9|pages=1716–1718|doi=10.1351/pac200476091715|issn=1365-3075|doi-access=free}}</ref> It was thus thought that spontaneous fission would occur nearly instantly before nuclei could form a structure that could stabilize them;<ref name="Oganessian122" /> it appeared that nuclei with Z{{spaces}}≈{{spaces}}103{{efn|"''Z''" means [[atomic number]]—number of protons. "''N''" means [[neutron number]]—number of neutrons. "''A''" means [[mass number]]—combined number of neutrons and protons.}} were too heavy to exist for a considerable length of time.<ref>{{Cite magazine|last=Dean|first=T.|date=2014|title=How to make a superheavy element|url=https://cosmosmagazine.com/physics/how-make-superheavy-element/|access-date=2020-07-04|magazine=[[Cosmos (Australian magazine)|Cosmos Magazine]]|archive-date=4 July 2020|archive-url=https://web.archive.org/web/20200704160434/https://cosmosmagazine.com/physics/how-make-superheavy-element/|url-status=dead}}</ref>

The later [[nuclear shell model]] suggested that nuclei with ~300 nucleons would form an [[island of stability]] where nuclei will be more resistant to spontaneous fission and will mainly undergo alpha decay with longer half-lives,<ref name="BrusselsSF" /><ref name="Oganessian042" /> and the next [[doubly magic]] nucleus (having magic numbers of both protons and neutrons) is expected to lie in the center of the island of stability near ''Z''{{spaces}}={{spaces}}110–114 and the predicted magic [[neutron number]] ''N''{{spaces}}={{spaces}}184. Subsequent discoveries suggested that the predicted island might be further than originally anticipated. They also showed that nuclei intermediate between the long-lived actinides and the predicted island are deformed, and gain additional stability from shell effects, against alpha decay and especially against spontaneous fission.<ref name="Oganessian042" /> The center of the region on a chart of nuclides that would correspond to this stability for deformed nuclei was determined as {{sup|270}}Hs, with 108 expected to be a magic number for protons for deformed nuclei—nuclei that are far from spherical—and 162 a magic number for neutrons for such nuclei.<ref>{{Cite journal|last=Schädel|first=M.|title=Chemistry of the superheavy elements|journal=Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences |date=2015|volume=373|issue=2037|pages=20140191|doi=10.1098/rsta.2014.0191 |pmid=25666065|bibcode=2015RSPTA.37340191S|issn=1364-503X|doi-access=free}}</ref> Experiments on lighter superheavy nuclei,<ref>{{Cite conference|last=Hulet |first=E. K.|date=1989|title=Biomodal spontaneous fission|conference=50th Anniversary of Nuclear Fission|bibcode=1989nufi.rept...16H}}</ref> as well as those closer to the expected island,<ref name="Oganessian122" /> have shown greater than previously anticipated stability against spontaneous fission, showing the importance of shell effects on nuclei.

Theoretical models predict a region of instability for some hassium isotopes to lie around ''A''{{spaces}}={{spaces}}275{{sfn|Zagrebaev|Karpov|Greiner|2013|pages=11–12}} and ''N''{{spaces}}={{spaces}}168–170, which is between the predicted neutron shell closures at ''N''{{spaces}}={{spaces}}162 for deformed nuclei and ''N''{{spaces}}={{spaces}}184 for spherical nuclei.<ref name="2012e1172">{{Cite journal|last1=Oganessian |first1=Yu. Ts.|last2=Abdullin|first2=F. Sh. |last3=Alexander|first3=C.|last4=Binder|first4=J.|last5=Boll |first5=R. A.|last6=Dmitriev|first6=S. N.|last7=Ezold|first7=J.|last8=Felker|first8=K.|last9=Gostic |first9=J. M.|display-authors=3|date=2013|title=Experimental studies of the <sup>249</sup>Bk + <sup>48</sup>Ca reaction including decay properties and excitation function for isotopes of element{{spaces}}117, and discovery of the new isotope <sup>277</sup>Mt|journal=Physical Review C |volume=87 |issue=5|pages=8–9|publisher=American Physical Society |bibcode=2013PhRvC..87e4621O |doi=10.1103/PhysRevC.87.054621|doi-access=free}}</ref> Nuclides in this region are predicted to have low fission barrier heights, resulting in short [[Partial half-life|partial half-lives]] toward spontaneous fission. This prediction is supported by the observed 11-millisecond half-life of {{sup|277}}Hs and the 5-millisecond half-life of the neighbouring [[Isobar (nuclide)|isobar]] {{sup|277}}Mt because the hindrance factors from the [[Even and odd atomic nuclei|odd nucleon]] were shown to be much lower than otherwise expected. The measured half-lives are even lower than those originally predicted for the even–even {{sup|276}}Hs and {{sup|278}}Ds, which suggests a gap in stability away from the shell closures and perhaps a weakening of the shell closures in this region.<ref name="2012e1172" />

In 1991, Polish physicists Zygmunt Patyk and Adam Sobiczewski predicted<ref>{{Cite journal|last1=Patyk|first1=Z.|last2=Sobiczewski|first2=A.|date=1991|title=Ground-state properties of the heaviest nuclei analyzed in a multidimensional deformation space|journal=Nuclear Physics A|volume=533|issue=1|page=150|bibcode=1991NuPhA.533..132P|doi=10.1016/0375-9474(91)90823-O}}</ref> that 108 is a proton magic number for deformed nuclei and 162 is a neutron magic number for such nuclei. This means such nuclei are permanently deformed in their ground state but have high, narrow fission barriers to further deformation and hence relatively long spontaneous-fission half-lives.<ref name="Focus2">{{cite magazine|last=Inman|first=M.|date=2006|title=A Nuclear Magic Trick|magazine=Physical Review Focus |volume=18|url=https://physics.aps.org/story/v18/st19|access-date=2006-12-25|url-status=live |archive-url=https://web.archive.org/web/20180602001137/https://physics.aps.org/story/v18/st19|archive-date=2 June 2018|doi=10.1103/physrevfocus.18.19}}</ref><ref name="Dvorak2">{{cite journal|last1=Dvorak|first1=J.|last2=Brüchle|first2=W.|last3=Chelnokov|first3=M.|last4=Dressler|first4=R.|last5=Düllmann|first5=Ch. E.|last6=Eberhardt|first6=K.|last7=Gorshkov|first7=V.|last8=Jäger|first8=E.|last9=Krücken|first9=R.|last10=Kuznetsov|first10=A.|last11=Nagame|first11=Y.|last12=Nebel|first12=F.|last13=Novackova|first13=Z.|display-authors=3|date=2006|title=Doubly Magic Nucleus <sub>108</sub><sup>270</sup>Hs<sub>162</sub>|url=https://www.dora.lib4ri.ch/psi/islandora/object/psi%3A16351|journal=Physical Review Letters|volume=97|issue=24|pages=242501|bibcode=2006PhRvL..97x2501D|doi=10.1103/PhysRevLett.97.242501|pmid=17280272|last24=Yeremin|first24=A.|last23=Yakushev|first23=A.|last22=Wierczinski|first22=B.|last21=Wegrzecki|first21=M.|last20=Türler|first20=A.|last19=Thörle|first19=P.|last18=Semchenkov|first18=A.|last17=Schimpf|first17=E.|last16=Schausten|first16=B.|first15=M.|last15=Schädel|last14=Qin|first14=Z.|access-date=20 August 2019|archive-date=16 November 2019|archive-url=https://web.archive.org/web/20191116170013/https://www.dora.lib4ri.ch/psi/islandora/object/psi:16351|url-status=live}}</ref> Computational prospects for shell stabilization for {{sup|270}}Hs made it a promising candidate for a deformed doubly magic nucleus.<ref name="Smolanczuk2">{{Cite journal|last=Smolańczuk|first=R.|date=1997|title=Properties of the hypothetical spherical superheavy nuclei|journal=[[Physical Review C]]|url=https://www.dora.lib4ri.ch/psi/islandora/object/psi%3A16351/datastream/PDF/Dvorak-2006-Doubly_magic_nucleus_108270Hs162-%28published_version%29.pdf|volume=56|issue=2|pages=812–824|bibcode=1997PhRvC..56..812S|doi=10.1103/PhysRevC.56.812|access-date=21 October 2019|archive-date=21 October 2019|archive-url=https://web.archive.org/web/20191021125835/https://www.dora.lib4ri.ch/psi/islandora/object/psi:16351/datastream/PDF/Dvorak-2006-Doubly_magic_nucleus_108270Hs162-(published_version).pdf|url-status=live}}</ref> Experimental data is scarce, but the existing data is interpreted by the researchers to support the assignment of ''N''{{spaces}}={{spaces}}162 as a magic number. In particular, this conclusion was drawn from the decay data of {{sup|269}}Hs, {{sup|270}}Hs, and {{sup|271}}Hs.{{efn|In particular, the low decay energy for <sup>270</sup>Hs matches calculations.<ref name="Dvorak2" /> The conclusion for <sup>269</sup>Hs was made after its decay data was compared to that of <sup>273</sup>Ds; the decay of the latter into the former has an energy sufficiently greater than the decay of the former (11.2{{spaces}}MeV and 9.2{{spaces}}MeV, respectively). The great value of the former energy was explained as a right-to-left crossing of ''N''{{spaces}}{{=}}{{spaces}}162 (<sup>273</sup>Ds has 163 neutrons and <sup>269</sup>Hs has 161).<ref>{{cite journal|last1=Hofmann |first1=S.|last2=Heßberger|first2=F.P.|last3=Ackermann|first3=D.|display-authors=3|last4=Münzenberg |first4=G.|last5=Antalic|first5=S.|last6=Cagarda|first6=P. |last7=Kindler|first7=B.|last8=Kojouharova |first8=J.|last9=Leino|first9=M.|last10=Lommel|first10=B.|last11=Mann|first11=R.|date=2002|title=New results on elements 111 and 112|journal=The European Physical Journal A|volume=14 |issue=2|page=155 |doi=10.1140/epja/i2001-10119-x|issn=1434-6001|bibcode=2002EPJA...14..147H|s2cid=8773326}}</ref> A similar observation and conclusion were made after measurement of decay energy of <sup>271</sup>Hs and <sup>267</sup>Sg.<ref>{{cite book|last1=Schädel|first1=M.|last2=Shaughnessy|first2=D.|date=2013|title=The Chemistry of Superheavy Elements|url=https://books.google.com/books?id=ei-_BAAAQBAJ|publisher=Springer Science & Business Media|isbn=978-3-642-37466-1|page=458|access-date=17 May 2020|archive-date=8 October 2024|archive-url=https://web.archive.org/web/20241008102954/https://books.google.com/books?id=ei-_BAAAQBAJ|url-status=live}}</ref>}} In 1997, Polish physicist [[Robert Smolańczuk]] calculated that the isotope {{sup|292}}Hs may be the most stable superheavy nucleus against alpha decay and spontaneous fission as a consequence of the predicted ''N''{{spaces}}={{spaces}}184 shell closure.<ref>{{cite journal|last1=Karpov|first1=A. V.|last2=Zagrebaev|first2=V. I.|last3=Palenzuela|first3=Y. M. |last4=Ruiz|first4=L. F.|last5=Greiner |first5=W.|display-authors=3|date=2012|title=Decay properties and stability of the heaviest elements|url=http://nrv.jinr.ru/karpov/publications/Karpov12_IJMPE.pdf |url-status=live|journal=[[International Journal of Modern Physics E]] |volume=21 |issue=2|pages=1250013-1–1250013-20|bibcode=2012IJMPE..2150013K|doi=10.1142/S0218301312500139|archive-url=https://web.archive.org/web/20161203230540/http://nrv.jinr.ru/karpov/publications/Karpov12_IJMPE.pdf |archive-date=3 December 2016|access-date=28 December 2018}}</ref><ref name="48Ca" />