Observation of the antimatter helium-4 nucleus at RHIC

We present the observation of the \Heebar nucleus, the heaviest antinucleus observed to date. In total, 18 \Heebar counts were detected at the STAR experiment at RHIC in 10$^{9}$ recorded Au+Au collisions at beam energies of $\sqrt{s_{NN}}$ = 200 GeV and 62 GeV. The background has been estimated, and the misidentification probability is found to be lower than 10$^{-11}$.Comment: 4 pages, 3 figures, to appear as proceedings of QM2011 conference at Annecy, Franc

Critical magnetic field in holographic superconductor in Gauss-Bonnet gravity with Born-Infeld electrodynamics

In the paper using matching method in the probe limit, we investigate some properties of holographic superconductor in Gauss-Bonnet gravity with Born-Infeld electrodynamics . We discuss the effects of the Gauss-Bonnet coupling \a and Born-Infeld parameter $b$ on the critical temperature and condensate. We find that both of \a and $b$ make the critical temperature decrease, which implies the condensate harder to form. Moreover we study the magnetic effect on holographic superconductor and obtain that the ratio between the critical magnetic field and the square of the critical temperature increases from zero as the temperature is lowered below the critical value $T_c$, which agrees well with the former results. We also find the critical magnetic field is indeed affected by Gauss-Bonnet coupling, but not by Born-Infeld parameter.Comment: 13 pages, 5 figure

A range extension for Haplomitrium mnioides (Lindb.) R.M.Schust.

Haplomitrium mnioides (Lindb.) R.M.Schust. is reported as new to Hainan Island. A continuous distribution of H. mnioides from west (Thailand) to east (Japan) is confirmed. Habitat pictures and a distribution map are provided

The radiative decays of 0++0^{++} and 1+−1^{+-} heavy mesons

The radiative decay is believed to be an ideal lab to study hadronic structure of newly observed resonances because the reactions are governed by only the electromagnetic interaction (tree level). However, to obtain correct theoretical values, one has to properly deal with the non-perturbative QCD effects in the wavefunction and hadronization. In this work we derive the formulas for the radiative decays of $0^{++}$ and $1^{-+}$ heavy mesons in the light front quark model (LFQM). Because $\mathcal{B}(\chi_{c0}\rightarrow J/\psi\gamma)$ is well measured, the theoretical evaluation of the transition rate can be used to test our approach. Within this theoretical framework, the width of $\chi_{b0}\rightarrow \Upsilon(1S)\gamma$ is evaluated. The formulas can be applied to identify the inner structures of new resonances, for example the isospin of $h_{c(b)}$ and the structure of $D_s(2317)$, via processes $h_c\rightarrow \eta_c\gamma$, $h_b\rightarrow \eta_b\gamma$ and $D_s(2317)\rightarrow D_s^*+\gamma$.Comment: 10 pages, 1 figure, Accepted by PR