Nuclear Theory·nucl-th

Monday·February 26, 2018

9 papers—4 primary·5 cross-listed

05
Lorentz-violating contributions to the nuclear Schiff moment and nuclear EDM
Jonas B. Araujo🇧🇷 · Rodolfo Casana🇧🇷 · Manoel M. Ferreira Jr🇧🇷
In the context of an atom endowed with nuclear electric dipole moment (EDM), we consider the effects on the Schiff moment of $C P T$ -even Lorentz-violating (LV) terms that modify the Coulomb potential. First, we study the modifications on the Schiff moment when the nucleus interacts with the electronic cloud by means of a Coulomb potential altered only by the $P$ -even LV components. Next, by supposing the existence of an additional intrinsic LV EDM generated by other LV sources, we assess the corrections to the Schiff moment when the interaction nucleus-electrons runs mediated by a Coulomb potential modified by both the $P$ -odd and $P$ -even LV components. We then use known estimates and EDM measurements to discuss upper bounds on the new Schiff moment components and the possibility of an intrisic nuclear EDM component ascribed to LV effects.
↳ hep-phhep-thnucl-thPRD(2018)·11 citations
06
Thermal Model Description of p--Pb Collisions at $s_{N N}$ = 5.02 TeV
Natasha Sharma🇮🇳 · Jean Cleymans🇿🇦 · Lokesh Kumar🇮🇳
The ALICE data on light flavor hadron production obtained in $p - P b$ collisions at $s_{N N}$ = 5.02 TeV are studied in the thermal model using the canonical approach with exact strangeness conservation. The chemical freeze-out temperature is independent of centrality except for the lowest multiplicity bin, with values close to 160 MeV but consistent with those obtained in $P b - P b$ collisions at $s_{N N}$ = 2.76 TeV. The value of the strangeness non-equilibrium factor $γ_{s}$ is slowly increasing with multiplicity from 0.9 to 0.96, i.e. it is always very close to full chemical equilibrium.
↳ hep-phnucl-thEPJC(2018)·19 citations
07
When gluons go odd: how classical gluon fields generate odd azimuthal harmonics for the two-gluon correlation function in high-energy collisions
Yuri V. Kovchegov🇺🇸 · Vladimir V. Skokov🇺🇸
We show that, in the saturation/Color Glass Condensate framework, odd azimuthal harmonics of the two-gluon correlation function with a long-range separation in rapidity are generated by the higher-order saturation corrections in the interactions with the projectile and the target. At the very least, the odd harmonics require three scatterings in the projectile and three scatterings in the target. We derive the leading-order expression for the two-gluon production cross section which generates odd harmonics: the expression includes all-order interactions with the target and three interactions with the projectile. We evaluate the obtained expression both analytically and numerically, confirming that the odd-harmonics contribution to the two-gluon production in the saturation framework is non-zero.
↳ hep-phnucl-exnucl-thPRD(2018)·41 citations
08
Testing dark decays of baryons in neutron stars
Gordon Baym🇺🇸 · D. H. Beck🇺🇸 · Peter Geltenbort🇫🇷 · Jessie Shelton🇺🇸
We demonstrate that the observation of neutron stars with masses greater than one solar mass places severe demands on any exotic neutron decay mode that could explain the discrepancy between beam and bottle measurements of the neutron lifetime. If the neutron can decay to a stable, feebly-interacting dark fermion, the maximum possible mass of a neutron star is 0.7 solar masses, while all well-measured neutron star masses exceed one solar mass. The survival of $2 M_{⊙}$ neutron stars therefore indicates that any explanation beyond the Standard Model for the neutron lifetime puzzle requires dark matter to be part of a multi-particle dark sector with highly constrained interactions.
↳ hep-phastro-ph.HEnucl-thPRL(2018)·123 citations
09
A femtoscopic Correlation Analysis Tool using the Schrödinger equation (CATS)
D.L. Mihaylov🇩🇪 · V. Mantovani Sarti🇩🇪 · O.W. Arnold🇩🇪 · L. Fabbietti🇩🇪 · B. Hohlweger🇩🇪 · A.M. Mathis🇩🇪
We present a new analysis framework called "Correlation Analysis Tool using the Schrödinger equation" (CATS) which computes the two-particle femtoscopy correlation function $C (k)$ , with $k$ being the relative momentum for the particle pair. Any local interaction potential and emission source function can be used as an input and the wave function is evaluated exactly. In this paper we present a study on the sensitivity of $C (k)$ to the interaction potential for different particle pairs: p-p, p- $Λ$ , $K^{-}$ -p, $K^{+}$ -p, p- $Ξ^{-}$ and $Λ$ - $Λ$ . For the p-p Argonne $v_{18}$ and Reid Soft-Core potentials have been tested. For the other pair systems we present results based on strong potentials obtained from effective Lagrangians such as $χ$ EFT for p- $Λ$ , Jülich models for $K (K ˉ)$ -N and Nijmegen models for $Λ$ - $Λ$ . For the p- $Ξ^{-}$ pairs we employ the latest lattice results from the HAL QCD collaboration. Our detailed study of different interacting particle pairs as a function of the source size and different potentials shows that femtoscopic measurements can be exploited in order to constrain the final state interactions among hadrons. In particular, small collision systems of the order of 1~fm, as produced in pp collisions at the LHC, seem to provide a suitable environment for quantitative studies of this kind.
↳ hep-phhep-exnucl-exnucl-thEPJC(2018)·122 citations

Affiliations

first authorsco-authorsvia INSPIRE

Lorentz-violating contributions to the nuclear Schiff moment and nuclear EDM

Thermal Model Description of p--Pb Collisions at sNN​​ = 5.02 TeV

When gluons go odd: how classical gluon fields generate odd azimuthal harmonics for the two-gluon correlation function in high-energy collisions

Testing dark decays of baryons in neutron stars

A femtoscopic Correlation Analysis Tool using the Schrödinger equation (CATS)

Affiliations

Thermal Model Description of p--Pb Collisions at $s_{N N}$ = 5.02 TeV