Editing Nihonium (section)

==== 2004–2008 ====
In June 2004 and again in December 2005, the JINR–LLNL collaboration strengthened their claim for the discovery of element 113 by conducting chemical experiments on <sup>268</sup>[[Dubnium|Db]], the final [[decay product]] of <sup>288</sup>115. This was valuable as none of the nuclides in this decay chain were previously known, so that their claim was not supported by any previous experimental data, and chemical experimentation would strengthen the case for their claim, since the chemistry of dubnium is known. <sup>268</sup>Db was successfully identified by extracting the final decay products, measuring [[spontaneous fission]] (SF) activities and using chemical identification techniques to confirm that they behave like a [[group 5 element]] (dubnium is known to be in group 5).<ref name="Haire" /><ref name="e115" /> Both the half-life and decay mode were confirmed for the proposed <sup>268</sup>Db which lends support to the assignment of the parent and [[daughter isotope|daughter nuclei]] to elements 115 and 113 respectively.<ref name="e115">{{cite journal |title=Chemical identification of dubnium as a decay product of element 115 produced in the reaction <sup>48</sup>Ca+<sup>243</sup>Am |first1=S. N. |last1=Dmitriev |first2=Yu. Ts. |last2=Oganessyan |first3=V. K. |last3=Utyonkov |first4=S. V. |last4=Shishkin |first5=A. V. |last5=Yeremin |first6=Yu. V. |last6=Lobanov |first7=Yu. S. |last7=Tsyganov |first8=V. I. |last8=Chepygin |first9=E. A. |last9=Sokol |first10=G. K. |last10=Vostokin |first11=N. V. |last11=Aksenov |first12=M. |last12=Hussonnois |first13=M. G. |last13=Itkis |first14=H. W. |last14=Gäggeler |first15=D. |last15=Schumann |first16=H. |last16=Bruchertseifer |first17=R. |last17=Eichler |first18=D. A. |last18=Shaughnessy |first19=P. A. |last19=Wilk |first20=J. M. |last20=Kenneally |first21=M. A. |last21=Stoyer |first22=J. F. |last22=Wild |journal=Mendeleev Communications |volume=15 |issue=1 |date=2005 |pages=1–4 |doi=10.1070/MC2005v015n01ABEH002077|s2cid=98386272 }}</ref><ref>{{cite journal |title=Synthesis of elements 115 and 113 in the reaction <sup>243</sup>Am + <sup>48</sup>Ca |doi=10.1103/PhysRevC.72.034611 |date=2005 |author=Oganessian, Yu. Ts. |journal=Physical Review C |volume=72 |pages=034611 |last2=Utyonkov |first2=V. |last3=Dmitriev |first3=S. |last4=Lobanov |first4=Yu. |last5=Itkis |first5=M. |last6=Polyakov |first6=A. |last7=Tsyganov |first7=Yu. |last8=Mezentsev |first8=A. |last9=Yeremin |first9=A.|first10=A. A. |last10=Voinov |first11=E. A. |last11=Sokol |first12=G. G. |last12=Gulbekian |first13=S. L. |last13=Bogomolov |first14=S. |last14=Iliev |first15=V. G. |last15=Subbotin |first16=A. M. |last16=Sukhov |first17=G. V. |last17=Buklanov |first18=S. V. |last18=Shishkin |first19=V. I. |last19=Chepygin|first20=G. K. |last20=Vostokin |first21=N. V. |last21=Aksenov |first22=M. |last22=Hussonnois |first23=K. |last23=Subotic |first24=V. I. |last24=Zagrebaev |first25=K. J. |last25=Moody |first26=J. B. |last26=Patin |first27=J. F. |last27=Wild |first28=M. A. |last28=Stoyer |first29=N. J. |last29=Stoyer|first30=D. A. |last30=Shaughnessy |first31=J. M. |last31=Kenneally |first32=P. A. |last32=Wilk |first33=R. W. |last33=Lougheed |first34=H. W. |last34=Gäggeler |first35=D. |last35=Schumann |first36=H. |last36=Bruchertseifer |first37=R. |last37=Eichler |issue=3 |bibcode=2005PhRvC..72c4611O|display-authors=10|url=https://www.dora.lib4ri.ch/psi/islandora/object/psi%3A13194}}</ref> Further experiments at the JINR in 2005 confirmed the observed decay data.<ref name="JWP" />

In November and December 2004, the Riken team studied the <sup>205</sup>Tl + <sup>70</sup>Zn reaction, aiming the zinc beam onto a [[thallium]] rather than a bismuth target, in an effort to directly produce <sup>274</sup>Rg in a cross-bombardment as it is the immediate daughter of <sup>278</sup>113. The reaction was unsuccessful, as the thallium target was [[Strength of materials|physically weak]] compared to the more commonly used lead and bismuth targets, and it deteriorated significantly and became non-uniform in thickness. The reasons for this weakness are unknown, given that thallium has a higher melting point than bismuth.<ref name="Morimoto2016" /> The Riken team then repeated the original <sup>209</sup>Bi + <sup>70</sup>Zn reaction and produced a second atom of <sup>278</sup>113 in April 2005<!--the 2nd-->, with a decay chain that again terminated with the spontaneous fission of <sup>262</sup>Db. The decay data were slightly different from those of the first chain: this could have been because an [[alpha particle]] escaped from the detector without depositing its full energy, or because some of the intermediate decay products were formed in [[metastable state|metastable isomeric states]].<ref name="JWP" />

In 2006, a team at the Heavy Ion Research Facility in [[Lanzhou]], China, investigated the <sup>243</sup>Am + <sup>26</sup>Mg reaction, producing four atoms of <sup>266</sup>Bh. All four chains started with an alpha decay to <sup>262</sup>Db; three chains ended there with spontaneous fission, as in the <sup>278</sup>113 chains observed at Riken, while the remaining one continued via another alpha decay to <sup>258</sup>Lr, as in the <sup>266</sup>Bh chains observed at LBNL.<ref name="Karol" />

In June 2006, the JINR–LLNL collaboration claimed to have synthesised a new isotope of element 113 directly by bombarding a [[neptunium]]-237 target with accelerated calcium-48 nuclei:

:{{nuclide|link=no|Neptunium|237}} + {{nuclide|link=no|Calcium|48}} → <sup>285</sup>113* → <sup>282</sup>113 + 3 {{SubatomicParticle|link=no|neutron}}

Two atoms of <sup>282</sup>113 were detected. The aim of this experiment had been to synthesise the isotopes <sup>281</sup>113 and <sup>282</sup>113 that would fill in the gap between isotopes produced via hot fusion (<sup>283</sup>113 and <sup>284</sup>113) and cold fusion (<sup>278</sup>113). After five alpha decays, these nuclides would reach known isotopes of [[lawrencium]], assuming that the decay chains were not terminated prematurely by spontaneous fission. The first decay chain ended in fission after four alpha decays, presumably originating from <sup>266</sup>Db or its electron-capture daughter <sup>266</sup>Rf. [[Spontaneous fission]] was not observed in the second chain even after four alpha decays. A fifth alpha decay in each chain could have been missed, since <sup>266</sup>Db can theoretically undergo alpha decay, in which case the first decay chain would have ended at the known <sup>262</sup>Lr or <sup>262</sup>No and the second might have continued to the known long-lived <sup>258</sup>Md, which has a half-life of 51.5&nbsp;days, longer than the duration of the experiment: this would explain the lack of a spontaneous fission event in this chain. In the absence of direct detection of the long-lived [[Alpha decay|alpha decays]], these interpretations remain unconfirmed, and there is still no known link between any superheavy nuclides produced by hot fusion and the well-known main body of the chart of nuclides.<ref name="07Og01">{{cite journal |url=http://nrv.jinr.ru/pdf_file/PhysRevC_76_011601.pdf |title=Synthesis of the isotope <sup>282</sup>113 in the <sup>237</sup>Np + <sup>48</sup>Ca fusion reaction |last1=Oganessian |first1=Yu. Ts. |journal=Physical Review C |volume=76 |issue=1 |page=011601(R) |year=2007 |doi=10.1103/PhysRevC.76.011601 |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. |last10=Gulbekian |first10=Gulbekian |last11=Bogomolov |first11=Bogomolov |last12=Gikal |first12=Gikal |last13=Mezentsev |first13=Mezentsev |last14=Subbotin |first14=Subbotin |last15=Sukhov |first15=Sukhov |last16=Subotic |first16=Subotic |last17=Zagrebaev |first17=Zagrebaev |last18=Vostokin |first18=Vostokin |last19=Itkis |first19=Itkis |last20=Henderson |first20=Henderson |last21=Kenneally |first21=Kenneally |last22=Landrum |first22=Landrum |last23=Moody |first23=Moody |last24=Shaughnessy |first24=Shaughnessy |last25=Stoyer |first25=Stoyer |last26=Stoyer |first26=Stoyer |last27=Wilk |first27=Wilk |bibcode=2007PhRvC..76a1601O |display-authors=10}}</ref>