Fri·Jul 24, 2009Friday·July 24, 2009

1. 01*

   Non-photonic electron-hadron azimuthal correlation for AuAu, CuCu and pp collisions at $\sqrt{s_{NN}}=200$ GeV

   Bertrand Biritz🇺🇸

   We present preliminary STAR results of azimuthal correlations between non-photonic electrons and hadrons in AuAu, CuCu and pp at $\sqrt{s_{NN}}=200$ GeV. Comparison of the e-h correlations from these colliding systems allows one to study the system-size dependence of heavy quark jet-medium interactions. We also report on the relative charm and bottom contributions to non-photonic electrons extracted from correlations measured in pp collisions. Our results, when combined with $R_{AA}$ measurements of non-photonic electrons, constrain the charm and bottom energy loss in the dense medium.

   nucl-exNPA(2009)·8 citations
2. 02*

   Fission studies with 140 MeV $\mathbf{\alpha }$-Particles

   A. Buttkewitz🇩🇪 · H. H. Duhm🇩🇪 · F. Goldenbaum🇩🇪 · H. Machner🇩🇪 · W. Strauss🇩🇪

   Binary fission induced by 140 MeV $\alpha$-particles has been measured for ${}^{\mathrm{nat}}$Ag, ${}^{139}$La, ${}^{165}$Ho and ${}^{197}$Au targets. The measured quantities are the total kinetic energies, fragment masses, and fission cross sections. The results are compared with other data and systematics. A minimum of the fission probability in the vicinity $Z^2/A=24$ is observed.

   nucl-exPRC(2009)·8 citations
3. 03*

   Search for the critical point of strongly interacting matter in NA49

   Katarzyna Grebieszkow (for the NA49 Collaboration)🇵🇱

   Theoretical calculations locate the QCD critical point at energies accessible at the CERN SPS. Several observables were suggested to look for it. Here, we present the system size dependence and the energy dependence of event-by-event mean transverse momentum and multiplicity fluctuations, as well as the energy dependence of anti-baryon to baryon ratios.

   nucl-exNPA(2009)·52 citations
4. 04*

   Extraction of Correlated Jet Pair Signals in Relativistic Heavy Ion Collisions

   Anne Sickles🇺🇸 · Michael P. McCumber🇺🇸 · Andrew Adare🇺🇸

   Multi-particle correlation techniques are frequently used to study jet shapes and yields in hadronic and nuclear collisions. To date, a standard assumption applied in such analyses is that the observed correlations arise from either jets and associated hard scattering phenomena, or from a background component due to combinatorial pairs connected only through whole even correlations. Within this assumption of two essentially independent sources, a fundamental problem centers around determining the relative contributions of each component. We discuss the methods commonly used to establish the background yield in jet correlation analyses, with a full explanation of the absolute background normalization technique which establishes the background yield without assumptions about the shape of jet correlations. This is especially important in relativistic heavy ion collisions where the jet shapes are significantly distorted from the well separated back-to-back di-jets observed in proton-proton collisions.

   nucl-exPRC(2010)·35 citations
5. 05*

   Energy loss for heavy quarks in relation to light partons; is radiative energy loss for heavy quarks anomalous?

   Roy A. Lacey🇺🇸 · R. Wei🇺🇸 · N. N. Ajitanand🇺🇸 · J. M. Alexander🇺🇸 · X. Gong🇺🇸 · J. Jia🇺🇸 · A. Mawi🇺🇸 · S. Mohapatra🇺🇸 · D. Reynolds🇺🇸 · S. Salnikov🇷🇺 · A. Taranenko (Chemistry Dept. Stony Brook University)🇺🇸

   The scaling properties of jet suppression measurements are compared for non-photonic electrons ($e^{\pm }$) and neutral pions (${\pi }^0$) in Au + Au collisions at $\sqrt{s_{NN}}=200$ GeV. For a broad range of transverse momenta and collision centralities, the comparison is consistent with jet quenching dominated by radiative energy loss for both heavy and light partons. Less quenching is indicated for heavy quarks via $e^{\pm }$; this gives an independent estimate of the transport coefficient $\hat{q}$ that agrees with its magnitude obtained from quenching of light partons via ${\pi }^0$'s.

   nucl-exPRL(2009)·18 citations
6. 06*

   Parity-violating polarization in $np\to d\gamma$ with a pionless effective field theory

   J. W. Shin🇰🇷 · S. Ando🇬🇧 · C. H. Hyun🇰🇷

   We consider the two-nucleon weak interaction with a pionless effective field theory. Dibaryon fields are introduced to facilitate calculations and ensure precision in the initial and final state propagators. Weak interactions are accounted for with the parity-violating dibaryon-nucleon-nucleon vertices, which contain unknown weak dibaryon-nucleon-nucleon coupling constants. We apply the model to the calculation of a parity-violating observable in the neutron-proton capture at threshold. Result is obtained up to the linear order in the unknown dibaryon-nucleon-nucleon coupling constants. We compare our result to the one obtained from a hybrid calculation, and discuss the extension to weak interactions in the few-body systems.

   ↳ nucl-thhep-phnucl-exPRC(2010)·34 citations
7. 07*

   NEXT, a HPGXe TPC for neutrinoless double beta decay searches

   The NEXT Collaboration: F. Granena🇪🇸 · T. Lux🇪🇸 · F. Nova🇪🇸 · J. Rico🇪🇸 · F. Sanchez🇪🇸 · D.R. Nygren🇺🇸 · J.A.S. Barata🇵🇹 · F.I.G.M. Borges🇵🇹 · C.A.N. Conde🇵🇹 · T.H.V.T. Dias🇵🇹 · L.M.P. Fernandes🇵🇹 · E.D.C. Freitas🇵🇹 and 51 other authors

   We propose a novel detection concept for neutrinoless double-beta decay searches. This concept is based on a Time Projection Chamber (TPC) filled with high-pressure gaseous xenon, and with separated-function capabilities for calorimetry and tracking. Thanks to its excellent energy resolution, together with its powerful background rejection provided by the distinct double-beta decay topological signature, the design discussed in this Letter Of Intent promises to be competitive and possibly out-perform existing proposals for next-generation neutrinoless double-beta decay experiments. We discuss the detection principles, design specifications, physics potential and R&D plans to construct a detector with 100 kg fiducial mass in the double-beta decay emitting isotope Xe(136), to be installed in the Canfranc Underground Laboratory.

   ↳ hep-exnucl-exphysics.ins-det112 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.