Abstract Spectroscopic information such as production, identification, half-lives, decay modes and possible excited states for experimentally known nuclides of mass numbers 268, 272, 276, 280, 284, 288, and 292 are presented together with the recommended values, superseding information and data in the previous ENSDF and NDS evaluation by 2005Gu33. No nuclides have yet been identified for A=296 and 300. In the last 14 years, large amounts of new and definitive data on the superheavy nuclides (SHN) have become available, thus changing almost entirely the landscape of nuclear data in this mass region, as also indicated by a number of recent review articles: 2017Og01, 2016Ho09, 2016Ho06 (for fission barriers), 2016Fo10, 2015Og05, 2015Og07, and 2013Th02. See 2003Ka71 and 2001Ka70 for IUPAC technical discussions about the discovery of Z=111 (Rg) and 2009Ba62 for discovery of Z=112(Cn), 2011Ba54 for discovery of Z=114 (Fl) and Z=116 (Lv) and 2016Ka49 for discovery of Z=113 (Nh) and Z=115 (Mc). A special issue of Nuclear Physics A444 (2015) is devoted to research on superheavy elements (SHE) with 27 articles. In particular, see article by 2015Ko20 on mass spectrometric searches for superheavy elements in terrestrial matter. See also Proceedings of Nobel Symposium NS160 ‘Chemistry and Physics of Heavy and Superheavy Elements’ published in Eur. Phys. Jour. Web of Conferences 131 (2016), in particular 2016UtZZ, 2016DmZZ and 2016HoZY. A=268: 268Db, 268Hs and 268Mt are the only experimentally identified nuclides with A=268. A=272: 272Bh and 272Rg are the only experimentally identified nuclides with A=272. A tentative level scheme for 272Bh has been proposed from the decay of 276Mt. Search for 272Ds in 235U(40Ar,3n),E=5.1-5.4 MeV/nucleon reaction and subsequent α decays at GSI (1990Sc11) proved negative with σ 0.8 nb . A=276: 276Mt is the only experimentally identified nuclide with A=276. A tentative level scheme has been proposed for this nuclide. A=280: 280Rg is the only experimentally identified nuclide with A=280. A tentative evidence is reported (2017Ka66) for 280Ds, based on one possible α-α-α correlated event at RIKEN. A=284: 284Cn, 284Nh and 284Fl are the only experimentally identified nuclides with A=284. First measurement of mass/charge (A/q) ratio has been made by 2018Ga34, resulting in the determination of A=284 for 284Nh. A=288: 288Fl and 288Mc are the only experimentally identified nuclides with A=288. Two independent experiments, first by Dubna-Livermore-ORNL collaboration using DGFRS at FLNR-JINR-Dubna (2004Og07,2004Og12), and the second at GSI using TASCA (2010Du06,2011Ga19) have confirmed the existence of 288Fl and 288Mc; and a third experiment at LBNL-Berkeley using BGS (2015Ga24) further confirmed the existence of 288Mc. Chemistry-related experiments for 288Fl have been reported by 2014Ya33 and 2010Ei01. First measurement of mass/charge (A/q) ratio has been made by 2018Ga34, resulting in the determination of A=288 for 288Mc. Search for 288Ds in natural Pt, Pb and Bi samples (2011De21) using accelerator mass spectroscopy (AMS) proved negative, with extremely low upper limits established. A=292: 292Lv is the only experimentally identified nuclide with A=292. Two independent experiments, one by Dubna-Livermore collaboration (2004Og12,2004OgZZ), and the other at GSI-SHIP facility (2012Ho12) confirm the identification of 292Lv, with the assignment of ten correlated events composed of Evaporation Residues (EVR)-α1-α2-SF correlated decay chains. Search for 292Rg in natural gold materials (2011De03), and for 292Ds and 292Fl in natural Pt, Pb and Bi samples (2011De21) using accelerator mass spectroscopy (AMS) proved negative, with extremely low upper limits established. 2010Ma03 proposed the existence of a very long-lived isomer in 122292 in their search of superheavy elements in natural Th sample using inductively-coupled plasma sector field mass spectroscopy, and interpreted the observed events as due to high-spin isomers of superdeformed or hyperdeformed character. This claim, however, for other nuclides in the superheavy element region has not been verified, for example in the AMS studies of natural samples such as Pt, Os, Au, Pb and Bi by 2011De21 and 2011De03. See also the publications of the Joint Working Party (JWP) of the IUPAC-IUPAP with critical appraisal of studies dealing with search of superheavy elements in natural samples. Specifically, for A=292, 2011De21 and 2011De21, using AMS technique, found no evidence for the existence of 292Ds, 292Rg and 292Fl in natural Pt, Pb, Bi and Au samples. See also replies to above critiques by 2009Ma19, Marinov et al., arXiv:0909.1057 (2009), and 2004MaZS A=296: Search for 296Rg in natural gold materials (2011De03), and for 296Fl and 296Mc in natural Pt, Pb and Bi samples (2011De21) using accelerator mass spectroscopy (AMS) proved negative, with extremely low upper limits established. See 2016DuZX for future prospects of discovery of elements beyond Z=118. There are no data tables for A=296. A=300: Search for 300Mc in natural Pt, Pb and Bi samples (2011De21) using accelerator mass spectroscopy (AMS) proved negative, with extremely low upper limits established. There are no data tables for A=300.

中文翻译：

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A=268,272,276,280,284,288,292 的核数据表

摘要 提供了质量数为 268、272、276、280、284、288 和 292 的实验已知核素的光谱信息，例如产生、识别、半衰期、衰变模式和可能的激发态以及推荐值、替代信息和 2005Gu33 之前的 ENSDF 和 NDS 评估中的数据。尚未确定 A=296 和 300 的核素。 在过去的 14 年中，大量关于超重核素 (SHN) 的新的和确定的数据已经可用，从而几乎完全改变了这个质量区域的核数据格局，正如最近的一些评论文章所指出的：2017Og01、2016Ho09、2016Ho06（用于裂变壁垒）、2016Fo10、2015Og05、2015Og07 和 2013Th02。IUPAC关于发现Z=111(Rg)的技术讨论见2003Ka71和2001Ka70，发现Z=112(Cn)见2009Ba62，发现Z=114(Fl)和Z=116(Lv)见2011Ba54，2016Ka4见2011Ba54发现 Z=113 (Nh) 和 Z=115 (Mc)。核物理专刊 A444 (2015) 致力于研究超重元素 (SHE)，共有 27 篇文章。特别是，请参阅 2015Ko20 发表的关于地球物质中超重元素的质谱搜索的文章。另请参阅在 Eur 上发表的诺贝尔研讨会论文集 NS160 '重元素和超重元素的化学和物理学'。物理。日。Web of Conferences 131 (2016)，特别是 2016UtZZ、2016DmZZ 和 2016HoZY。A=268：268Db、268Hs 和 268Mt 是唯一通过实验确定的 A=268 的核素。A=272：272Bh 和 272Rg 是唯一通过实验确定的 A=272 的核素。从 276Mt 的衰变中提出了 272Bh 的暂定水平方案。在 235U(40Ar,3n),E=5.1-5.4 MeV/核子反应中寻找 272Ds，随后 GSI (1990Sc11) 的 α 衰变证明为负值，σ 0.8 nb 。A=276：276Mt 是唯一通过实验确定的 A=276 的核素。已经为这种核素提出了一个暂定的水平方案。A=280：280Rg 是唯一通过实验确定的 A=280 的核素。根据 RIKEN 的一个可能的 α-α-α 相关事件，报告了 280D 的初步证据 (2017Ka66)。A=284：284Cn、284Nh 和 284Fl 是唯一通过实验确定的 A=284 的核素。2018Ga34 首次测量了质荷比 (A/q)，结果确定 284Nh 的 A=284。A=288：288Fl 和 288Mc 是唯一通过实验确定的 A=288 的核素。两个独立的实验，首先是 Dubna-Livermore-ORNL 在 FLNR-JINR-Dubna (2004Og07,2004Og12) 上使用 DGFRS 合作，第二次在 GSI 上使用 TASCA (2010Du06,2011Ga19) 证实了 288Fl 和 288Mc 的存在；LBNL-Berkeley 使用 BGS (2015Ga24) 进行的第三次实验进一步证实了 288Mc 的存在。288Fl 的化学相关实验已在 2014Ya33 和 2010Ei01 报告。2018Ga34 首次测量了质荷比 (A/q)，结果确定 288Mc 的 A=288。使用加速器质谱 (AMS) 在天然 Pt、Pb 和 Bi 样品 (2011De21) 中搜索 288D 被证明是负面的，并且建立了极低的上限。A=292：292Lv 是唯一通过实验确定的 A=292 的核素。两个独立实验，一个由 Dubna-Livermore 合作 (2004Og12,2004OgZZ)，另一个在 GSI-SHIP 设施 (2012Ho12) 确认了 292Lv 的识别，分配了由蒸发残留物 (EVR)-α1-α2-SF 相关衰变链组成的十个相关事件。使用加速器质谱 (AMS) 在天然金材料 (2011De03) 中搜索 292Rg 以及在天然 Pt、Pb 和 Bi 样品 (2011De21) 中搜索 292Ds 和 292Fl 被证明是阴性的，并且建立了极低的上限。2010Ma03 在使用电感耦合等离子体扇形场质谱法寻找天然 Th 样品中的超重元素时，提出了 122292 中存在一个非常长寿命的异构体，并将观察到的事件解释为由于超变形或超变形特征的高自旋异构体. 然而，这种说法对于超重元素区的其他核素尚未得到证实，例如，在 2011De21 和 2011De03 对 Pt、Os、Au、Pb 和 Bi 等天然样品的 AMS 研究中。另请参阅 IUPAC-IUPAP 联合工作组 (JWP) 的出版物，其中包含对处理在自然样品中寻找超重元素的研究的批判性评价。具体而言，对于 A=292、2011De21 和 2011De21，使用 AMS 技术，没有发现天然 Pt、Pb、Bi 和 Au 样品中存在 292D、292Rg 和 292Fl 的证据。另请参阅 2009Ma19、Marinov 等人对上述评论的答复，arXiv:0909.1057 (2009) 和 2004MaZS A=296：在天然金材料中搜索 296Rg (2011De03)，以及在天然金材料中寻找 296Fl、Pb 和 296Fl、Pb使用加速器质谱 (AMS) 的样品 (2011De21) 被证明是阴性的，并且建立了极低的上限。未来发现 Z=118 以外元素的前景见 2016DuZX。A=296 没有数据表。A=300：使用加速器质谱 (AMS) 在天然 Pt、Pb 和 Bi 样品 (2011De21) 中搜索 300Mc 被证明是负面的，并且建立了极低的上限。A=300 没有数据表。