Nuclear Theory·nucl-th

Tuesday·February 10, 2015

12 papers—4 primary·8 cross-listed

01
Techniques for multiboson interferometry
Dhevan Gangadharan🇺🇸
The quantum statistics (QS) correlations of identical bosons are well known to be sensitive to the space-time extent and dynamics of the particle emitting source in high-energy collisions. While two-pion correlations are most often experimentally measured, the QS correlations of three-pions and higher are rarely explored. We present a set of techniques to isolate and analyze 3- and 4-pion QS correlations. In particular, the technique of built correlation functions allows one to more easily study the effects of quantum coherence at finite relative momenta instead of at the unmeasured intercept of correlation functions.
nucl-thnucl-exPRC(2015)·28 citations
02
Effect of first forbidden decays on the shape of neutrino spectra
Dong-Liang Fang🇺🇸 · B. Alex Brown🇺🇸
We examine the effect of First Forbidden (FF) decays on $β$ -decay neutrino spectra by performing microscopic nuclear structure calculations. By analyzing the FF decay branches of even-even nuclei we conclude that FF decays may be responsible for part of the missing neutrinos in the so called "Reactor Neutrino Anomaly". Further calculations and more experimental data are needed for a firm conclusion.
nucl-thhep-phPRC(2015)·43 citations
03
Isospin splitting of nucleon effective mass and shear viscosity of nuclear matter
Jun Xu
Based on an improved isospin- and momentum-dependent interaction, we have studied the qualitative effect of isospin splitting of nucleon effective mass on the specific shear viscosity of neutron-rich nuclear matter from a relaxation time approach. It is seen that for $m_{n}^{⋆} > m_{p}^{⋆}$ , the relaxation time of neutrons is smaller and the neutron flux between flow layers is weaker, leading to a smaller specific shear viscosity of neutron-rich matter compared to the case for $m_{n}^{⋆} < m_{p}^{⋆}$ . The effect is larger in nuclear matter at higher densities, lower temperatures, and larger isospin asymmetries, but it doesn't affect much the behavior of the specific shear viscosity near nuclear liquid-gas phase transition.
nucl-thPRC(2015)·14 citations
04
$v_{4}$ , $v_{5}$ , $v_{6}$ , $v_{7}$ : nonlinear hydrodynamic response versus LHC data
Li Yan🇫🇷 · Jean-Yves Ollitrault🇫🇷
Higher harmonics of anisotropic flow ( $v_{n}$ with $n \geq 4$ ) in heavy-ion collisions can be measured either with respect to their own plane, or with respect to a plane constructed using lower-order harmonics. We explain how such measurements are related to event-plane correlations. We show that CMS data on $v_{4}$ and $v_{6}$ are compatible with ATLAS data on event-plane correlations. If one assumes that higher harmonics are the superposition of non-linear and linear responses, then the linear and non-linear parts can be isolated under fairly general assumptions. By combining analyses of higher harmonics with analyses of $v_{2}$ and $v_{3}$ , one can eliminate the uncertainty from initial conditions and define quantities that only involve nonlinear hydrodynamic response coefficients. Experimental data on $v_{4}$ , $v_{5}$ and $v_{6}$ are in good agreement with hydrodynamic calculations. We argue that $v_{7}$ can be measured with respect to elliptic and triangular flow. We present predictions for $v_{7}$ versus centrality in Pb-Pb collisions at the LHC.
nucl-thhep-phnucl-exPLB(2015)·127 citations

Affiliations

first authorsco-authorsvia INSPIRE

Techniques for multiboson interferometry

Effect of first forbidden decays on the shape of neutrino spectra

Isospin splitting of nucleon effective mass and shear viscosity of nuclear matter

v4​, v5​, v6​, v7​: nonlinear hydrodynamic response versus LHC data

Affiliations

$v_{4}$ , $v_{5}$ , $v_{6}$ , $v_{7}$ : nonlinear hydrodynamic response versus LHC data