Nuclear Theory·nucl-th

Thursday·December 15, 2016

9 papers—4 primary·5 cross-listed

01
[Submitted on 14 Dec 2016]
Evidence of a proton halo in $^{23}$ Al: A mean field analysis
R. N. Panda · M. Panigrahi · Mahesh K. Sharma · S. K. Patra
We have studied the nuclear structure properties like binding energy, charge radius, quadrupole deformation parameter for various isotopes of Al from the valley of stability to drip line region using the well known relativistic mean field formalism (RMF) with NL3 parameter set. We have compared our results with experimental data and found reasonable agreement. Further, we have taken spherical and deformed RMF densities to estimate the reaction dynamics of $^{23 - 28}$ Al isotopes as projectiles and $^{12}$ C as target by conjunction in Glauber model. The estimated results are also compared with the experimental data. The analysis of angular elastic differential and one proton removal cross sections are also studied with Glauber model many body system to investigate the structural feature of $^{23}$ Al. The evidence of enhanced total reaction cross section, higher value of rms radius, narrow longitudinal momentum distribution and small proton separation energy of $^{23}$ Al support its proton halo structure.
Comments:
12 pages, 10 figures
Subjects:
Nuclear Theory (nucl-th)
arXiv:
1612.04534 [pdf]
Phys.Atom.Nucl.(2018)·11 citations
02
[Submitted on 14 Dec 2016]
Behavior of universal critical parameters in the QCD phase diagram
Marcus Bluhm (North Carolina State U.)🇺🇸 · Marlene Nahrgang (SUBATECH, Nantes and Duke U.)🇺🇸 · Steffen A. Bass (Duke U.)🇺🇸 · Thomas Schaefer (North Carolina State U.)🇺🇸
We determine the dependence of important parameters for critical fluctuations on temperature and baryon chemical potential in the QCD phase diagram. The analysis is based on an identification of the fluctuations of the order parameter obtained from the Ising model equation of state and the Ginzburg-Landau effective potential approach. The impact of the mapping from Ising model variables to QCD thermodynamics is discussed.
Comments:
Contribution to the Proceedings of Strangeness in Quark Matter 2016, Berkeley, USA
Subjects:
Nuclear Theory (nucl-th); High Energy Physics — Phenomenology (hep-ph)
arXiv:
1612.04564 [pdf]
J.Phys.Conf.Ser.(2017)·8 citations
03
[Submitted on 14 Dec 2016]
An effective two-body model for spectra of clusters of $^{2}$ H, $^{3}$ H, $^{3}$ He, and $^{4}$ He with $^{4}$ He, and $^{2}$ H- $^{4}$ He scattering
P. R. Fraser · K. Massen-Hane · A. S. Kadyrov · K. Amos · I. Bray · L. Canton
Four light-mass nuclei are considered by an effective two-body clusterisation method; $^{6}$ Li as $^{2}$ H $+^{4}$ He, $^{7}$ Li as $^{3}$ H $+^{4}$ He, $^{7}$ Be as $^{3}$ He $+^{4}$ He, and $^{8}$ Be as $^{4}$ He $+^{4}$ He. The low-energy spectrum of each is determined from single-channel Lippmann-Schwinger equations, as are low-energy elastic scattering cross sections for the $^{2}$ H $+^{4}$ He system. These are presented at many angles and energies for which there are data. While some of these systems may be more fully described by many-body theories, this work establishes that a large amount of data may be explained by these two-body clusterisations.
Comments:
14 pages, 5 figures
Subjects:
Nuclear Theory (nucl-th)
arXiv:
1612.04649 [pdf]
PRC(2017)·6 citations
04
[Submitted on 14 Dec 2016]
Study of shape coexistence in the 180-190Hg isotopes by SO(6) representation of eigenstates
H. Sabri · O. Jabbarzade · A. Ghale Asadi · S. K. Mousavi Mobarake
In this paper, we have studied the shapes coexistence in the 180-190Hg isotopes. The SO(6) representation of eigenstates and a transitional Hamiltonian in the Interacting Boson Model are used to consider the evolution from prolate to oblate shapes for systems with total boson number N = 9-12. Parameter free (up to overall scale factors) predictions for energy spectra and quadrupole transition rates are found to be in good agreement with experimental counterparts. The results for the control parameter of transitional Hamiltonian offer a combination of spherical and deformed shapes in these Hg isotopes and also more deviation from SO(6) limit is observed when the quadrupole deformation is decreased. Also, there are some suggestion about the expectation values of operator which are determined in the first state of ground, beta and gamma bounds and the control parameter of model.
Comments:
27 pages, 8 figures, 8 tables. arXiv admin note: text overlap with arXiv:1509.02282; text overlap with arXiv:1312.4595 by other authors
Subjects:
Nuclear Theory (nucl-th)
arXiv:
1612.04678 [pdf]
IJMPE(2017)·2 citations
05
[Submitted on 23 Jul 2016] (cross-list from hep-ph)
Remarks on meson loop effects on quark models
I. K. Hammer🇩🇪 · C. Hanhart🇩🇪 · A. V. Nefediev🇷🇺
We investigate the effect of meson loops on the spectrum of quark states. We demonstrate that in general quark states do not tend to get very broad if their coupling to the continuum increases, but instead they decouple from the latter in the large coupling limit. We ascribe this effect to the essentially nonperturbative unitarization procedure involved. In the meantime, some quark resonances behave very differently and demonstrate collectivity in the sense that their pole trajectories span a wide, as compared to the level spacing, region therefore acquiring contributions from multiple bare poles rather than from the closest neighbors. While the actual calculations are done within particular, very simplified models, it is argued that the findings might well be general.
Comments:
15 pages, 17 figures
Subjects:
High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Experiment (hep-ex); High Energy Physics — Lattice (hep-lat); Nuclear Theory (nucl-th)
arXiv:
1607.06971 [pdf]
EPJA(2016)·19 citations
06
[Submitted on 14 Dec 2016] (cross-list from hep-ph)
Forward $J / ψ$ and $D$ meson nuclear suppression at the LHC
B. Ducloué🇫🇮 · T. Lappi🇫🇮 · H. Mäntysaari🇺🇸
Using the color glass condensate formalism, we study the nuclear modification of forward $J / ψ$ and $D$ meson production in high energy proton-nucleus collisions at the LHC. We show that relying on the optical Glauber model to obtain the dipole cross section of the nucleus from the one of the proton fitted to HERA DIS data leads to a smaller nuclear suppression than in the first study of these processes in this formalism and a better agreement with experimental data.
Comments:
4 pages, 3 figures. Hard Probes 2016 proceedings
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
1612.04585 [pdf]
Nucl.Part.Phys.Proc.(2017)·28 citations
07
[Submitted on 14 Dec 2016] (cross-list from hep-th)
Relativistic Chiral Kinetic Theory from Quantum Field Theories
Yoshimasa Hidaka🇯🇵 · Shi Pu🇯🇵 · Di-Lun Yang🇯🇵
The chiral kinetic theory of Weyl fermions with collisions in the presence of weak electric and magnetic fields is derived from quantum field theories. It is found that the side-jump terms in the perturbative solution of Wigner functions play a significant role for the derivation. Moreover, such terms manifest the breaking of Lorentz symmetry for distribution functions. The Lorentz covariance of Wigner functions thus leads to modified Lorentz transformation associated with side-jump phenomena further influenced by background fields and collisions.
Comments:
6 pages, journal version, accepted by PRD rapid communication
Subjects:
High Energy Physics — Theory (hep-th); Mesoscale and Nanoscale Physics (cond-mat.mes-hall); Nuclear Theory (nucl-th)
arXiv:
1612.04630 [pdf]
PRD(2017)·208 citations
08
[Submitted on 14 Dec 2016] (cross-list from hep-lat)
Novel applications of Lattice QCD: Parton distribution functions, proton charge radius and neutron electric dipole moment
Constantia Alexandrou (Univ. of Cyprus and The Cyprus Inst.)🇨🇾
We briefly discuss the current status of lattice QCD simulations and review selective results on nucleon observables focusing on recent developments in the lattice QCD evaluation of the nucleon form factors and radii, parton distribution functions and their moments, and the neutron electric dipole moment. Nucleon charges and moments of parton distribution functions are presented using simulations generated at physical values of the quark masses, while exploratory studies are performed for the parton distribution functions and the neutron electric dipole moment at heavier than physical value of the pion mass.
Comments:
Plenary talk at XII Quark Confinement, 29 August - 3 September, 2016, Thessaloniki, Greece, 20 pages, 21 figures
Subjects:
High Energy Physics — Lattice (hep-lat); High Energy Physics — Phenomenology (hep-ph); Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
arXiv:
1612.04644 [pdf]
EPJ Web Conf.(2017)·15 citations
09
[Submitted on 7 Dec 2016] (cross-list from hep-th)
Schwinger's proper time and worldline holographic renormalisation
Dennis D. Dietrich🇩🇪 · Adrian Koenigstein🇩🇪
Worldline holography states that within the framework of the worldline approach to quantum field theory, sources of a quantum field theory over Mink $_{4}$ naturally form a field theory over AdS $_{5}$ {\sl to all orders} in the elementary fields and in the sources of arbitrary spin. (Such correspondences are also available for other pairs of spacetimes, not only Mink $_{4} \leftrightarrow AdS_{5}$ .) Schwinger's proper time of the worldline formalism is automatically grouped with the physical four spacetime dimensions into an AdS $_{5}$ geometry. We show that the worldline holographic effective action in general and the proper-time profiles of the sources in particular solve a renormalisation group equation and, reversely, can be defined as solution to the latter. This fact also ensures regulator independence.
Comments:
12 pages
Subjects:
High Energy Physics — Theory (hep-th); High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
1612.04658 [pdf]
PRD(2017)·2 citations

Affiliations

first authorsco-authorsvia INSPIRE