The new element 111

Abstract

The new element 111 was produced and unambiguously identified in an experiment at SHIP, GSI Darmstadt. Three nudlei of the isotope 272111 were observed in irradiations of 2~ targets with a4Ni projectiles of 318 MeV and 320 MeV energy. The cross-sections are (1.72~ pb and (3.5_ +4-6) pb, respectively. The nuclei decay by cc emission into the new and so far the heaviest isotopes of the elements 109 and 107 with mass numbers A = 268 and A=264. The ~-decay chains were followed down to the known nuclei 260105 and 256Lr.

Development of an Odd-Z-Projectile Reaction for Heavy Element Synthesis:Pb208(Folden1, Gregorich2, Düllmann3 et al. 2004Phys. Rev. Lett.700160View full textAdd to dashboardCite

“…Pb( 64 Ni, n) 271 Ds excitation function was measured first to aid in the estimation of the optimum 65 Cu beam energy for the production of 272 111. The current work serves as an independent confirmation of the discovery of element 111 [6] using a different reaction. It also demonstrates a rather simple method for estimating optimum projectile energies for production of heavy elements in cold fusion reactions which have very narrow excitation functions.…”

Eleven new heaviest isotopes of elementsZ=105toZ=117identified among the products ofOganessian1, Abdullin2, Bailey3 et al. 2011Phys. Rev. C1255350View full textAdd to dashboardCite

“…Despite the strong hindrance, spontaneous fission is a principal decay mode of the odd-even nucleus 281 Rg. Note that all of the lighter isotopes of element Z = 111, the 280 Rg, 279 Rg [20,21] and 278 Rg [22] produced in reactions with 48 Ca, as well as 274 Rg [49,50] and 272 Rg [51][52][53][54] produced in cold fusion experiments are α-emitters. The heavier isotope 282 Rg registered in the decay chain at E * ≈ 35 MeV undergoes α-decay as well.…”

Are MCDF calculations 101% correct in the super-heavy elements range?

“…Elements 108 (Hs) [5][6][7], 109 (Mt) [8][9][10], 110 (Ds) [11], 111 (Rg) [12], 112 [13][14][15], 113 [16], 114 [17][18][19][20], 115 [3], 116 [21][22][23], 117 [24] and 118 [25,23] have been observed in a series of experiments in Berkeley, GSI, Dubna and RIKEN. Chemistry of transactinide elements 104 (Rf) to 108 has been performed one atom at a time (see, e.g., [26] for a review).…”