Investigation of the reaction 64Ni+238U being an option of synthesizing element 120.

This study is concerned with the search for entrance channels suitable to synthesize elements with Z > 118. Mass–energy distributions as well as capture cross-sections of fission-like fragments have been measured for the reactions 64Ni+238U→302120 and 48Ca+238U → 286112 at energies near the Coulomb barrier. Compound nucleus fission cross-sections were estimated from the analysis of mass and total kinetic energy distributions. The cross-section drops three orders of magnitude for the formation of the compound nucleus with Z = 120 obtained in the reaction 64Ni + 238U compared to the formation of the compound nucleus with Z = 112 obtained in the reaction 48Ca + 238U at an excitation energy of the compound nucleus of about 45 MeV. From our analysis it turns out that the reaction 64Ni + 238U is not suitable for the synthesis of element Z = 120

Measurement of charm production at central rapidity in proton-proton collisions at 1as = 2.76 TeV

The p t-differential production cross sections of the prompt (B feed-down subtracted) charmed mesons D0, D+, and D*+ in the rapidity range |y| < 0.5, and for transverse momentum 1 < p t < 12 GeV/c, were measured in proton-proton collisions at 1as = 2.76 TeV with the ALICE detector at the Large Hadron Collider. The analysis exploited the hadronic decays D 0 \u2192 K -\u3c0 +, D + \u2192 K -\u3c0 +\u3c0 +, D *+ \u2192 D 0\u3c0 +, and their charge conjugates, and was performed on a L int = 1.1 nb -1 event sample collected in 2011 with a minimum-bias trigger. The total charm production cross section at 1as = 2.76 TeV and at 7 TeV was evaluated by extrapolating to the full phase space the p t-differential production cross sections at 1as = 2.76 TeV and our previous measurements at 1as = 7 TeV. The results were compared to existing measurements and to perturbative-QCD calculations. The fraction of cd D mesons produced in a vector state was also determined. \ua9 2012 SISSA