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Abstract Spectroscopic information such as production, identification, half-lives, decay modes and possible excited states for experimentally known nuclides of mass numbers 266, 270, 274, 278, 282, 286, 290, 294, and 298 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=302. 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), 2015Og05, 2015Og07, 2015Mo25, 2015OgZX, 2013Th02, and 2011Og07. See 2016Ka49 for IUPAC technical discussions for the discovery of Z=117 (Ts), Z=115 (Mc), Z=113 (Nh), 2001Ka70 and 2003Ka71 for Z=110-112, 2011Ba54 for Z≥113, 2009Ba62 for Z=112, and 2016Ka50 for Z=118 (Og). 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. See also 2016DuZX for future prospects of discovery of elements beyond Z=118 A = 266 : 266Db, 266Sg, 266Bh, 266Hs and 266Mt are the experimentally identified nuclides with A=266. Identification of 266Lr from α decay of 270Db has been proposed by 2014Kh04 from experiments at GSI, but complete details and analyses of all the four decay chains reported in this experiment have not yet been published, and discussion in 2015Og05 review article considering their work from Dubna (2013Og04, 2011Og04) and from GSI (2014Kh04) still concluded that 270Db decayed dominantly by SF mode, in contrast with dominant α decay mode proposed by 2014Kh04. Experiments carried out at FLNR-JINR-Dubna in collaboration with LLNL and ORNL, GSI-SHIP facility, RIKEN, and LBNL facilities: 266Db from the α -decay of 282Nh in two correlated decay chains at Dubna; 266Sg as α -daughter of 270Hs in 12 correlated decay chains at Dubna and GSI; 266Bh in α decay of 278Nh in three correlated decay chains observed at RIKEN, and also directly with one event in 249Bk(22Ne,5n) at LBNL, and with four events in 243Am(26Mg,3n) at HIRFL-Lanzhou; 266Hs as α -daughter of 270Ds at GSI in two different experiments, six correlated decays in the first, and 25 decay chains in the second experiment, the analysis of which has not been fully reported as yet; and 266Mt directly in 209Bi(58Fe,n) reaction at GSI in two different experiments, observing three events in the first experiment and 12 events in the second, also produced in 208Pb(59Co,n) reaction at LBNL, observing five correlated decay chains. See also 2000Ho27 for discussion on 266Sg and 266Mt. A = 270 : 270Db, 270Bh, 270Hs, 270Mt and 270Ds are the experimentally identified nuclides with A=270 are presented. Experiments carried out at FLNR-JINR-Dubna in collaboration with LLNL and ORNL, GSI-SHIP facility, and RIKEN: 270Db from the decay of 294Ts in six correlated decay chains at Dubna and GSI; 270Bh as α great-granddaughter of 282Nh in two correlated decay chains observed at Dubna; 270Hs directly in 248Cm(26Mg,4n) reaction at GSI, and in 226Ra(48Ca,4n) reaction at Dubna; 270Mt as granddaughter of 278Ts in three correlated decay chains at RIKEN; and 270Ds directly in 207Pb(64Ni,n) at GSI in 33 correlated decay chains. A = 274 : 274Bh, 274Mt and 274Rg are the experimentally identified nuclides with A=274. Search for 274Ds in 238U(40Ar, 4n),E=5.7 MeV/nucleon reaction and subsequent α decays at GSI (1990Sc11) proved negative. Experiments carried out at FLNR-JINR-Dubna in collaboration with LLNL and ORNL, GSI-SHIP facility, and RIKEN: 274Bh from the decay of 294Ts in six correlated decay chains at Dubna and GSI, 274Mt produced as α daughter of 282Nh in two correlated decay chains observed at Dubna, and 274Rg as α daughter of 278Nh produced in three correlated decay chains at RIKEN. A = 278 : 278Mt, 278Rg and 278Nh are the experimentally identified nuclides with A=278. A very tentative evidence is provided for 278Bh and 278Hs from a chain originally observed and assigned to 289Fl by 1999Og10, but later reassigned by 2004Og10 to 290Fl, and further discussed in detail by 2016Ho09, where, based on systematics of α decays and SF half-lives, 290Fl is proposed to decay via ε mode to 290Nh, which then decays by an α chain, ending in 278Bh that decays by SF mode. Experiments carried out at FLNR-JINR-Dubna in collaboration with LLNL and ORNL labs in the USA, GSI-SHIP facility, and RIKEN: 278Mt from the decay of 294Ts in six correlated decay chains at Dubna and GSI, 278Rg produced as α daughter of 282Nh in two correlated decay chains observed at Dubna, and 278Nh produced directly in three correlated decay chains at RIKEN. A = 282 : 282Rg, 282Cn and 282Nh are the experimentally identified nuclides with A=282. A very tentative evidence is provided for 282Mt and 282Ds from a chain originally observed and assigned to 289Fl by 1999Og10, but later reassigned by 2004Og10 to 290Fl, and further discussed in detail by 2016Ho09, where, based on systematics of α decays and SF half-lives, 290Fl is proposed to decay via ε mode to 290Nh, which then decays by an α chain, ending in 278Bh that decays by SF mode. Experiments carried out at FLNR-Dubna, in collaboration with LLNL and ORNL labs in the USA, and at GSI-SHIP facility confirm the identification of these isotopes, 282Rg in α decay chain of 294Ts in six correlated decay chains at Dubna and GSI, 282Cn produced in four ways at Dubna: independently in one correlated decay chain, as α daughter of 286Lv in 11 correlated decay chains, as α grand-daughter of 290Lv in 12 correlated decay chains, as α great-grand daughter of 294Og in four correlated decay chains, and 282Nh produced at Dubna directly in two correlated decay chains. A = 286 : 286Nh and 286Fl are the only experimentally identified nuclides with A=286. A very tentative evidence is provided for 286Rg and 286Cn from a chain originally observed and assigned to 289Fl by 1999Og10, but later reassigned by 2004Og10 to 290Fl, and further discussed in detail by 2016Ho09, where, based on systematics of α decays and SF half-lives, 290Fl is proposed to decay via ε mode to 290Nh, which then decays by an α chain, ending in 278Bh that decays by SF mode. 2017Ka66 in experiments at RIKEN using GARIS separator interpret one correlated decay chain in three different ways, one involving possible production of 294Lv in 248Cm(48Ca,2n),E=261.6 MeV, and α decay to 290Fl which further decays to 286Cn. Experiments carried out at FLNR-Dubna, in collaboration with LLNL and ORNL labs in the USA, and at GSI-SHIP facility confirm the identification of these isotopes, 286Nh as α grand-daughter of 294Ts in six correlated decay chains, and 286Fl produced in three ways: independently in 11 correlated decay chains, as α daughter of 290Lv in 12 correlated decay chains, and as α grand-daughter of 294Og in four correlated decay chains. A = 290 : 290Mc and 290Lv are the only experimentally identified nuclides with A=290. A tentative evidence is provided for 290Nh and 290Fl from a chain originally observed and assigned to 289Fl by 1999Og10, but later reassigned by 2004Og10 to 290Fl, and further discussed in detail by 2016Ho09, where, based on systematics of α decays and SF half-lives, 290Fl is proposed to decay via ε mode to 290Nh, which then decays by an α chain, ending in 278Bh that decays by SF mode. 2017Ka66 in experiments at RIKEN using GARIS separator interpret one correlated decay chain in three different ways, one involving possible production of 294Lv in 248Cm(48Ca,2n),E=261.6 MeV, and α decay to 290Fl. Experiments carried out at FLNR-Dubna, in collaboration with LLNL and ORNL labs in the USA, and at GSI-SHIP facility confirm the identification of these isotopes, 290Mc as α daughter of 294Ts in six correlated decay chains, and 290Lv produced in two ways, independently in 14 correlated decay chains, and as α daughter of 294Og in four correlated decay chains. A = 294 : 294Ts and 294Og are the only experimentally identified nuclides with A=294. Experiments carried out at FLNR-Dubna, in collaboration with LLNL and ORNL labs in the USA, and at GSI-SHIP facility confirm the identification of these isotopes, with a total of six EVR- α -SF correlated decay chains observed for 294Ts and four for 294Og. Tentative identification of 294Lv is provided by 2017Ka66 from the observation one correlated event using GARIS-RIKEN facility, where this event is interpreted in three possible ways, two interpretations lead to production of 293Lv and successive odd-A nuclides of 289Fl, 285Cn and 281Ds, whereas the third prediction starts with the production of 294Lv and successive 290Fl and 286Cn nuclides. Search for 294Rg in natural gold materials (2011De03), and for 294Ds, 294Fl and 294Mc in natural Pt, Pb and Bi samples (2011De21) using accelerator mass spectroscopy (AMS) proved negative, with extremely low upper limits established. Also 1980St05 did not see any evidence for 294Ds in natural Pt sample using AMS. A = 298 : Search for 298120 through fusion-evaporation reaction at Dubna, and for 298Fl and 298Mc in natural Pt, Pb and Bi samples using accelerator mass spectroscopy (AMS) proved negative. Tentative assignment of three α - α - α decay chains by 2016Ho09 to 299120 in 248Cm(54Cr,3n)299120 at GSI was refuted by 2017He11, assigning these correlations to random events, instead. A = 302 : Fluorescent x rays from Z=120 element were observed by 2012Fr03 from compound nucleus 302120 produced in 238U(64Ni,X),E=6.6 MeV/nucleon at GANIL, and x-ray yields were measured, together with minimum average time deduced from x-ray multiplicity. The compound nucleus could decay by 3n- or 4n-channels to produce 299120 or 298120. 2012He05 and 2016Ho09 also produced 302120 compound nucleus in 248Cm(54Cr, xn)302120*,E=6.035 MeV/nucleon; and 238U(64Ni,xn)302120*,E=5.53 MeV/nucleon reactions using UNILAC at GSI. Three α - α - α correlated decays from 248Cm(54Cr,xn)302120* reaction were tentatively assigned by 2016Ho09 to 299120 decay, however, a detailed analysis by 2017He11 refuted this claim, ascribing these events to random sequences. There are no data tables for A=302. [ABSTRACT FROM AUTHOR]