Tue·Oct 27, 2015Tuesday·October 27, 2015

1. 01*

   Photon-hadron and photon-photon collisions in ALICE

   R. Schicker (for the ALICE Collaboration)🇩🇪

   A review is given on photon-hadron and photon-photon collisions in the ALICE experiment. The physics motivation for studying such reactions is outlined, and the results obtained in proton-lead and lead-lead collisions in Run 1 of the LHC are discussed. The improvement in detector rapidity coverage due to a newly added detector system is presented. The ALICE perspectives for data taking in LHC Run II are summarised.

   nucl-exhep-ex0 citations
2. 02*

   Nuclear Chiral EFT in the Precision Era

   Evgeny Epelbaum🇩🇪

   Chiral effective field theory has established itself as the method of choice to study nuclear forces and low-energy nuclear dynamics. I review the status and prospects of this approach and discuss ongoing efforts to advance the precision frontier for ab initio description of few-nucleon systems. Special emphasis is put on the precise determination of the two-nucleon force at fifth order in the chiral expansion, role of the chiral symmetry, the convergence pattern of the chiral expansion and the quantification of the theoretical uncertainties. The discussed topics are essential for ongoing studies towards elucidating the structure of the three-nucleon force which will be briefly addressed as well.

   ↳ nucl-thhep-phnucl-exPoS(2016)·16 citations
3. 03*

   Status and Outlook of CHIP-TRAP: the Central Michigan University High Precision Penning Trap

   Matthew Redshaw🇺🇸 · Richard A. Bryce · Paul Hawks · Nadeesha D. Gamage · Curtis Hunt · Rathnayake M. E. B. Kandegedara · Ishara S. Ratnayake · Lance Sharp

   At Central Michigan University we are developing a high-precision Penning trap mass spectrometer (CHIP-TRAP)that will focus on measurements with long-lived radioactive isotopes. CHIP-TRAP will consist of a pair of hyperbolic precision-measurement Penning traps, and a cylindrical capture/filter trap in a 12 T magnetic field. Ions will be produced by external ion sources, including a laser ablation source, and transported to the capture trap at low energies enabling ions of a given m=q ratio to be selected via their time-of-flight. In the capture trap, contaminant ions will be removed with a mass-selective rf dipole excitation and the ion of interest will be transported to the measurement traps. A phase-sensitive image charge detection technique will be used for simultaneous cyclotron frequency measurements on single ions in the two precision traps, resulting in a reduction in statistical uncertainty due to magnetic field fluctuations.

   ↳ physics.ins-detnucl-exNucl.Instrum.Meth.B(2016)·6 citations
4. 04*

   Baryon resonances in the strangeness production

   Ju-Jun Xie🇨🇳 · En Wang🇨🇳 · Jia-Jun Wu🇦🇺

   We have studied the $N^{\ast }(2120)$, ${\Delta }^{\ast }(1940)$, and the possible ${\Sigma }^{\ast }(1380)$ resonances in the $\gamma p\to K^{+}\Lambda (1520)$, $pp\to n{K}^{+}\Sigma (1385)$, and $\Lambda p\to \Lambda p{\pi }^0$ reactions within the resonance model and the effective Lagrangian approach. It is shown that when the contributions from these baryonic states were considered, the current experimental measurement could be well reproduced. In addition, we also demonstrate that the angular distributions provide direct information of these reactions, which could be useful for the investigation of those states and may be tested by future experiments.

   ↳ nucl-thhep-phnucl-exJPS Conf.Proc.(2016)·0 citations
5. 05*

   The ${\Xi }^{\ast }\bar{K}$ and $\Omega \eta$ interaction within a chiral unitary approach

   Siqi Xu🇨🇳 · Ju-Jun Xie🇨🇳 · Xurong Chen🇨🇳 · Duojie Jia🇨🇳

   In this work we study the interaction of the coupled channels $\Omega \eta$ and ${\Xi }^{\ast }\bar{K}$ within the chiral unitary approach. The systems under consideration have total isospins $0$, strangeness $S=-3$, and spin $3/2$. We studied the $s$ wave interaction which implies that the possible resonances generated in the system can have spin-parity $J^P=3/2^{-}$. The unitary amplitudes in coupled channels develop poles that can be associated with some known baryonic resonances. We find there is a dynamically generated $3/2^{-}$ $\Omega$ state with mass around $1800$ MeV, which is in agreement with the predictions of the five-quark model.

   ↳ nucl-thhep-exhep-phnucl-exCommun.Theor.Phys.(2016)·18 citations
6. 06*

   Heavy-flavor dynamics in relativistic p-Pb collisions at $\sqrt{S_{NN}}=5.02$ TeV

   Yingru Xu🇺🇸 · Shanshan Cao🇺🇸 · Marlene Nahrgang🇺🇸 · Weiyao Ke🇺🇸 · Guang-You Qin🇨🇳 · Jussi Auvinen🇺🇸 · Steffen A. Bass🇺🇸

   We investigate the heavy flavor dynamics in the quark-gluon plasma (QGP) medium created in p-Pb collisions at the CERN Large Hadron Collider (LHC). In the (3+1)-dimensional viscous hydrodynamics model describing QGP medium, the dynamics of heavy quarks are studied in an improved Langevin framework incorporating both collisional and radiative energy loss. The hadronization of the heavy quarks is given by a hybrid model of fragmentation and recombination. We find that the in-medium evolution of charm quarks raises the D-meson $R_{pPb}$ at low transverse momenta while it suppresses the D-meson $R_{pPb}$ at intermediate momenta. In addition, the elliptic flow of D-meson is calculated. For a diffusion coefficient which reproduces central $R_{AA}$ data at the LHC, we find a much smaller D-meson $v_2$ compared to the light hadrons. This observation indicates an incomplete coupling between heavy quarks with the medium, due to the reduced medium size compared to AA collisions.

   ↳ nucl-thnucl-exNucl.Part.Phys.Proc.(2016)·40 citations
7. 07*

   Chemical Freeze-out Parameters via a Non-perturbative QCD Approach

   Jing Chen🇨🇳 · Fei Gao🇨🇳 · Yu-xin Liu🇨🇳

   By analyzing the calculated baryon number susceptibility ratios ${\chi }_1^B/{\chi }_2^B$ and ${\chi }_3^B/{\chi }_1^B$ in two-flavor system via the Dyson-Schwinger equation approach of QCD, we determine the chemical freeze-out temperature and baryon chemical potential in cases of both thermodynamic limit and finite size. We calculate the center-of-mass energy dependence of the ${\chi }_4^B/{\chi }_2^B(\kappa {\sigma }^2)$ at the freeze-out line and find an excellent agreement with experimental data in $\sqrt{S_{NN}^{}}\ge 19.6$GeV region when taking into account the finite size effect. Our calculations indicate that the $\kappa {\sigma }^2$ exhibits a non-monotonic behavior in lower collision energy region.

   ↳ hep-phnucl-exnucl-th6 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.