Nuclear Theory·nucl-th

Tuesday·August 22, 2017

13 papers—7 primary·6 cross-listed

08
[Submitted on 18 Aug 2017] (cross-list from nucl-ex)
Photoproduction prospects at the EIC
Heikki Mäntysaari🇺🇸
We discuss how photoproduction and electroproduction processes will provide a precise tool to study nuclear structure in the small- $x$ region in the future Electron-Ion Collider. In particular, we emphasize how exclusive vector meson production at the EIC can be used to accurately map the gluonic density profile of nuclei, including its event-by-event fluctuations. In addition, we show how measurements of the total diffractive cross section will be sensitive to saturation effects.
Comments:
5 pages, 6 figures. Invited talk at the Photon 2017 conference
Subjects:
Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
arXiv:
1708.05756 [pdf]
CERN Proc.(2018)·1 citation
09
[Submitted on 18 Aug 2017] (cross-list from hep-ph)
On the absorption and production cross sections of $K$ and $K^{*}$
A. Martinez Torres🇧🇷 · K. P. Khemchandani🇧🇷 · L. M. Abreu🇧🇷 · F. S. Navarra🇧🇷 · M. Nielsen🇧🇷
We have computed the isospin and spin averaged cross sections of the processes $π K^{*} \to ρ K$ and $ρ K^{*} \to π K$ , which are crucial in the determination of the abundances of $K^{*}$ and $K$ in heavy ion collisions. Improving previous calculations, we have considered several mechanisms which were missing, such as the exchange of axial and vector resonances ( $K_{1} (1270)$ , $K_{2}^{*} (1430)$ , $h_{1} (1170)$ , etc...) and also other processes such as $π K^{*} \to ω K, ϕ K$ and $ω K^{*}, ϕ K^{*} \to π K$ . We find that some of these mechanisms give important contributions to the cross section. Our results also suggest that, in a hadron gas, $K^{*}$ production might be more important than its absorption.
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
1708.05784 [pdf]
PRD(2018)·10 citations
10
[Submitted on 19 Aug 2017] (cross-list from hep-ph)
Dependencies of Lepton Angular Distribution Coefficients on the Transverse Momentum and Rapidity of $Z$ Bosons Produced in $pp$ Collisions at LHC
Wen-Chen Chang🇹🇼 · Randall Evan McClellan🇺🇸 · Jen-Chieh Peng🇺🇸 · Oleg Teryaev🇷🇺
High precision data of lepton angular distributions for $γ^{*} / Z$ production in $pp$ collisions at the LHC, covering broad ranges of dilepton transverse momenta ( $q_{T}$ ) and rapidity ( $y$ ), were recently reported. Strong $q_{T}$ dependencies were observed for several angular distribution coefficients, $A_{i}$ , including $A_{0} - A_{4}$ . Significant $y$ dependencies were also found for the coefficients $A_{1}$ , $A_{3}$ and $A_{4}$ , while $A_{0}$ and $A_{2}$ exhibit very weak rapidity dependence. Using an intuitive geometric picture we show that the $q_{T}$ and $y$ dependencies of the angular distributions coefficients can be well described.
Comments:
9 pages, 9 figures, some typos corrected
Subjects:
High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Experiment (hep-ex); Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
arXiv:
1708.05807 [pdf]
PRD(2017)·17 citations
11
[Submitted on 20 Aug 2017] (cross-list from gr-qc)
Non-radial Oscillation Modes of Compact Stars with a Crust
C. Vasquez Flores🇧🇷 · Zack B. Hall II🇺🇸 · Prashanth Jaikumar🇺🇸
Oscillation modes of isolated compact stars can, in principle, be a fingerprint of the equation of state (EoS) of dense matter. We study the non-radial high-frequency l=2 spheroidal modes of neutron stars and strange quark stars, adopting a two-component model (core and crust) for these two types of stars. Using perturbed fluid equations in the relativistic Cowling approximation, we explore the effect of a strangelet or hadronic crust on the oscillation modes of strange stars. The results differ from the case of neutron stars with a crust. In comparison to fluid-only configurations, we find that a solid crust on top of a neutron star increases the p-mode frequency slightly with little effect on the f-mode frequency, whereas for strange stars, a strangelet crust on top of a quark core significantly increases the f-mode frequency with little effect on the p-mode frequency.
Comments:
10 pages, 6 figures
Subjects:
General Relativity and Quantum Cosmology (gr-qc); Nuclear Theory (nucl-th)
arXiv:
1708.05985 [pdf]
PRC(2017)·50 citations
12
[Submitted on 20 Aug 2017] (cross-list from hep-ph)
Fermi Liquid Model for Hadrons in Medium
A. Bhattacharya🇮🇳 · S. Pal🇮🇳 · R. Ghosh🇮🇳 · B.Chakrabarti🇮🇳
A Fermi liquid model for hadrons has been suggested for the hadrons in medium. The hadrons are supposed to behave like quasi particle as Fermi excitation while in the medium and the effective mass of the hadrons have been estimated using Fermi liquid model. Considering a momentum dependent potential inside the medium to describe the interaction, the effective masses of the hadrons are estimated. The temperature dependence of effective masses has also been studied. The possibility of describing masses of the quarks as Fermi excitation has been investigated. Compressibility, specific heats, density of states in medium has been studied. The potential depth for light and singly heavy baryons in medium has been extracted. The results are found to be very interesting and compared with the other studies available in literature.
Comments:
18 pages, 14 figures
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
1708.05995 [pdf]
0 citations
13
[Submitted on 18 Aug 2017] (cross-list from gr-qc)
Causality and existence of solutions of relativistic viscous fluid dynamics with gravity
Fabio S. Bemfica (Rio Grande do Norte U.)🇧🇷 · Marcelo M. Disconzi (Vanderbilt U.)🇺🇸 · Jorge Noronha (Sao Paulo U.)🇧🇷
A new approach is described to help improve the foundations of relativistic viscous fluid dynamics and its coupling to general relativity. Focusing on neutral conformal fluids constructed solely in terms of hydrodynamic variables, we derive the most general viscous energy-momentum tensor yielding equations of motion of second order in the derivatives, which is shown to provide a novel type of generalization of the relativistic Navier-Stokes equations for which causality holds. We show how this energy-momentum tensor may be derived from conformal kinetic theory. We rigorously prove existence, uniqueness, and causality of solutions of this theory (in the full nonlinear regime) both in a Minkowski background and also when the fluid is dynamically coupled to Einstein's equations. Linearized disturbances around equilibrium in Minkowski spacetime are stable in this causal theory. A numerical study reveals the presence of an out-of-equilibrium hydrodynamic attractor for a rapidly expanding fluid. Further properties are also studied and a brief discussion of how this approach can be generalized to non-conformal fluids is presented.
Comments:
33 pages, 5 figures. Substantial improvements were made: the new conformal tensor is now derived from kinetic theory; the causality and well-posedness theorems now hold under more general conditions on the transport coefficients; further discussion and applications have also been included; new references were added
Subjects:
General Relativity and Quantum Cosmology (gr-qc); High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Theory (hep-th); Mathematical Physics (math-ph); math.MP (math.MP); Nuclear Theory (nucl-th)
arXiv:
1708.06255 [pdf]
PRD(2018)·285 citations

Affiliations

first authorsco-authorsvia INSPIRE

Photoproduction prospects at the EIC

On the absorption and production cross sections of K and K∗

Dependencies of Lepton Angular Distribution Coefficients on the Transverse Momentum and Rapidity ofZ Bosons Produced in pp Collisions at LHC

Non-radial Oscillation Modes of Compact Stars with a Crust

Fermi Liquid Model for Hadrons in Medium

Causality and existence of solutions of relativistic viscous fluid dynamics with gravity

Affiliations

On the absorption and production cross sections of $K$ and $K^{*}$

Dependencies of Lepton Angular Distribution Coefficients on the Transverse Momentum and Rapidity of $Z$ Bosons Produced in $pp$ Collisions at LHC