Nuclear Theory·nucl-th

Tuesday·June 28, 2016

10 papers—6 primary·4 cross-listed

07
[Submitted on 11 Jun 2016] (cross-list from cond-mat.quant-gas)
Chiral magnetic effect by synthetic gauge fields
Tomoya Hayata🇯🇵 · Masahito Ueda🇯🇵
We study the dynamical generation of the chiral chemical potential in a Weyl metal constructed from a three-dimensional optical lattice and subject to synthetic gauge fields. By numerically solving the Boltzmann equation with the Berry curvature in the presence of parallel synthetic electric and magnetic fields, we find that the spectral flow and the ensuing chiral magnetic current emerge. We show that the spectral flow and the chiral chemical potential can be probed by time-of-flight imaging.
Comments:
5 pages, 5 figures
Subjects:
Quantum Gases (cond-mat.quant-gas); Mesoscale and Nanoscale Physics (cond-mat.mes-hall); High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Theory (hep-th); Nuclear Theory (nucl-th)
arXiv:
1606.03589 [pdf]
1 citation
08
[Submitted on 26 Jun 2016] (cross-list from hep-th)
Yang-Mills correlators across the deconfinement phase transition
U. Reinosa🇫🇷 · J. Serreau🇫🇷 · M. Tissier🇫🇷 · A. Tresmontant🇫🇷
We compute the finite temperature ghost and gluon propagators of Yang-Mills theory in the Landau-DeWitt gauge. The background field that enters the definition of the latter is intimately related with the (gauge-invariant) Polyakov loop and serves as an equivalent order parameter for the deconfinement transition. We use an effective gauge-fixed description where the nonperturbative infrared dynamics of the theory is parametrized by a gluon mass which, as argued elsewhere, may originate from the Gribov ambiguity. In this scheme, one can perform consistent perturbative calculations down to infrared momenta, which have been shown to correctly describe the phase diagram of Yang-Mills theories in four dimensions as well as the zero-temperature correlators computed in lattice simulations. In this article, we provide the one-loop expressions of the finite temperature Landau-DeWitt ghost and gluon propagators for a large class of gauge groups and present explicit results for the SU(2) case. These are substantially different from those previously obtained in the Landau gauge, which corresponds to a vanishing background field. The nonanalyticity of the order parameter across the transition is directly imprinted onto the propagators in the various color modes. In the SU(2) case, this leads, for instance, to a cusp in the electric and magnetic gluon susceptibilities as well as similar signatures in the ghost sector. We mention the possibility that such distinctive features of the transition could be measured in lattice simulations in the background field gauge studied here.
Comments:
28 pages, 17 figures; published version
Subjects:
High Energy Physics — Theory (hep-th); High Energy Physics — Lattice (hep-lat); High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
1606.08012 [pdf]
PRD(2017)·33 citations
09
[Submitted on 26 Jun 2016] (cross-list from nucl-ex)
Finite-Size Scaling of Non-Gaussian Fluctuations Near the QCD Critical Point
Roy A. Lacey (1,2)🇺🇸 · Peifeng Liu (1,2)🇺🇸 · Niseem Magdy (1)🇺🇸 · B. Schweid (1,2)🇺🇸 · N. N. Ajitanand (1) ((1) Department of Chemistry, Stony Brook University, (2) Dept. of Physics, Stony Brook University)🇺🇸
An effective Finite-Size Scaling (FSS) of moment products from recent STAR measurements of the variance $σ$ , skewness $S$ and kurtosis $κ$ of net-proton multiplicity distributions, are reported for a broad range of collision centralities in Au+Au ( $s_{N N} = 7.7 - 200$ GeV) collisions. The products $S σ$ and $κ σ^{2}$ , which are directly related to the hgher-order baryon number susceptibility ratios $χ_{B}^{(3)} / χ_{B}^{(2)}$ and $χ_{B}^{(4)} / χ_{B}^{(2)}$ , show scaling patterns consistent with earlier indications for a second order phase transition at a critical end point (CEP) in the plane of temperature vs. baryon chemical potential ( $T, μ_{B}$ ) of the QCD phase diagram. The resulting scaling functions validate the earlier estimates of $T^{cep} \sim 165$ MeV and $μ_{B}^{cep} \sim 95$ MeV for the location of the CEP, and the critical exponents used to assign its 3D Ising model universality class.
Comments:
5 pages, 3 figures, submitted for publication. Effective Finite-Size-Scaling procedure clarified in this version
Subjects:
Nuclear Experiment (nucl-ex); High Energy Physics — Experiment (hep-ex); Nuclear Theory (nucl-th)
arXiv:
1606.08071 [pdf]
11 citations
10
[Submitted on 27 Jun 2016] (cross-list from hep-ph)
Hidden-charm pentaquarks as a meson-baryon molecule with coupled channels for $D ˉ^{(*)} Λ_{c}$ and $D ˉ^{(*)} Σ_{c}^{(*)}$
Yasuhiro Yamaguchi🇮🇹 · Elena Santopinto🇮🇹
The recent observation of two hidden-charm pentaquark states by LHCb collaborations prompted us to investigate the exotic states close to the $D ˉ Λ_{c}$ , $D ˉ^{*} Λ_{c}$ , $D ˉ Σ_{c}$ , $D ˉ Σ_{c}^{*}$ , $D ˉ^{*} Σ_{c}$ and $D ˉ^{*} Σ_{c}^{*}$ thresholds. We therefore studied the hadronic molecules that form the coupled-channel system of $D ˉ^{(*)} Λ_{c}$ and $D ˉ^{(*)} Σ_{c}^{(*)}$ . As the heavy quark spin symmetry manifests the mass degenerations of $D ˉ$ and $D ˉ^{*}$ mesons, and of $Σ_{c}$ and $Σ_{c}^{*}$ baryons, the coupled channels of $D ˉ^{(*)} Σ_{c}^{(*)}$ are important in these molecules. In addition, we consider the coupling to the $D ˉ^{(*)} Λ_{c}$ channel whose thresholds are near the $D ˉ^{(*)} Σ_{c}^{(*)}$ thresholds, and the coupling to the state with nonzero orbital angular momentum mixed by the tensor force. This full coupled channel analysis of $D ˉ^{(*)} Λ_{c} - D ˉ^{(*)} Σ_{c}^{(*)}$ with larger orbital angular momentum has never been performed before. By solving the coupled-channel Schrödinger equations with the one meson exchange potentials that respected to the heavy quark spin and chiral symmetries, we studied the hidden-charm hadronic molecules with $I (J^{P}) = 1/2 (3/ 2^{\pm})$ and $1/2 (5/ 2^{\pm})$ . We conclude that the $J^{P}$ assignment of the observed pentaquarks is $3/ 2^{+}$ for $P_{c}^{+} (4380)$ and $5/ 2^{-}$ for $P_{c}^{+} (4450)$ , which is agreement with the results of the LHCb analysis. In addition, we give predictions for other $J^{P} = 3/ 2^{\pm}$ states at 4136.0, 4307.9 and 4348.7 MeV in $J^{P} = 3/ 2^{-}$ , and 4206.7 MeV in $J^{P} = 3/ 2^{+}$ , which can be further investigated by means of experiment.
Comments:
8 pages, 1 figure and 5 tables
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
1606.08330 [pdf]
PRD(2017)·83 citations

Affiliations

first authorsco-authorsvia INSPIRE

Chiral magnetic effect by synthetic gauge fields

Yang-Mills correlators across the deconfinement phase transition

Finite-Size Scaling of Non-Gaussian Fluctuations Near the QCD Critical Point

Hidden-charm pentaquarks as a meson-baryon molecule with coupled channels for Dˉ(∗)Λc​ and Dˉ(∗)Σc(∗)​

Affiliations

Hidden-charm pentaquarks as a meson-baryon molecule with coupled channels for $D ˉ^{()} Λ_{c}$ and $D ˉ^{()} Σ_{c}^{(*)}$