Fri·Oct 7, 2011Friday·October 7, 2011

1. 01*

   Reconstruction of Jet Properties in Pb-Pb Collisions with the ALICE-Experiment

   Christian Klein-Boesing (for the ALICE Collaboration)🇩🇪

   The study of the hot and dense medium created in heavy-ion collisions via the effect of parton energy loss is one of the major goals of jet and high-\pt\ measurements in these reactions. In particular the modifications of the longitudinal and transverse jet structure. Here the subtraction of the underlying heavy-ion event, as well as a precise knowledge of the background induced fluctuations of the reconstructed jet energy is required. We extract the modification of the near- and away-side jet yield in heavy-ion collisions at the LHC and present a detailed assessment of background fluctuations for jet reconstruction.

   nucl-exhep-exAIP Conf.Proc.(2012)·2 citations
2. 02*

   Spectroscopy of ${}^{18}$Na: Bridging the two-proton radioactivity of ${}^{19}$Mg

   M. Assié🇫🇷 · F. de Oliveira Santos🇫🇷 · T. Davinson · F. de Grancey🇫🇷 · L. Achouri🇫🇷 · J. Alcántara-Núñez🇫🇷 · T. Al Kalanee · J.-C. Angélique🇫🇷 · C. Borcea🇷🇴 · R. Borcea · L. Caceres🇫🇷 · I. Celikovic and 22 other authors

   The unbound nucleus ${}^{18}$Na, the intermediate nucleus in the two-proton radioactivity of ${}^{19}$Mg, was studied by the measurement of the resonant elastic scattering reaction ${}^{17}$Ne(p,${}^{17}$Ne)p performed at 4 A.MeV. Spectroscopic properties of the low-lying states were obtained in a R-matrix analysis of the excitation function. Using these new results, we show that the lifetime of the ${}^{19}$Mg radioactivity can be understood assuming a sequential emission of two protons via low energy tails of ${}^{18}$Na resonances.

   nucl-exPLB(2012)·15 citations
3. 03*

   Stochastic potential and quantum decoherence of heavy quarkonium in the quark-gluon plasma

   Yukinao Akamatsu🇯🇵 · Alexander Rothkopf🇩🇪

   We propose an open quantum systems approach to the physics of heavy quarkonia in a thermal medium, based on stochastic quantum evolution. This description emphasizes the importance of collisions with the environment and focuses on the concept of spatial decoherence of the heavy quarkonium wave function. It is shown how to determine the parameters of the dynamical evolution, i.e. the real potential and the noise strength, from a comparison with quantities to be obtained from lattice QCD. Furthermore the imaginary part of the lattice QCD heavy quark potential is found to be naturally related to the strength of the noise correlations. We discuss the time evolution of $Q\bar{Q}$ analytically in a limiting scenario for the spatial decoherence and provide a qualitative 1-dimensional numerical simulation of the real-time dynamics.

   ↳ hep-phnucl-exnucl-thquant-phPRD(2012)·137 citations
4. 04*

   Impurity effect of $\Lambda$ hyperon on shape-coexistence nucleus ${}^{44}$S in the energy functional based collective Hamiltonian

   H. Mei🇨🇳 · Z. P. Li🇨🇳 · J. M. Yao🇨🇳 · K. Hagino🇯🇵

   The non-relativistic Skyrme energy density functional (EDF) based collective Hamiltonian, that takes into account dynamical correlations related to the restoration of broken symmetries and fluctuations of quadrupole collective variables, is applied to quantitatively study the impurity effect of $\Lambda$ hyperon on the collectivity of ${}^{44}$S. Several Skyrme forces for both the nucleon-nucleon ($NN$) and $\Lambda$-nucleon ($\Lambda N$) interactions are used. The influence of pairing strengths on the polarization effect of $\Lambda$ hyperon is also examined. It is found that although these Skyrme forces with different pairing strengths give somewhat different low-lying spectra for ${}^{44}$S, all of them give similar and generally small size of $\Lambda$ reduction effect (within 5%) on the collective properties.

   ↳ nucl-thnucl-exIJMPE(2012)·2 citations

* Reconstructed cohort: no mailing for this day survives in the archive. Papers are grouped by their submission times and arXiv's announcement cut-off, assuming announcement without delay; positions follow identifier order. Validated at ~91% exact-day agreement against the archived era.