Nuclear Theory·nucl-th

Friday·February 6, 2015

11 papers—5 primary·6 cross-listed

01
[Submitted on 5 Feb 2015]
Charged particle assisted nuclear reactions in solid state environment: renaissance of low energy nuclear physics
Péter Kálmán · Tamás Keszthelyi
The features of electron assisted neutron exchange processes in crystalline solids are survayed. It is stated that, contrary to expectations, the cross section of these processes may reach an observable magnitude even in the very low energy case because of the extremely huge increment caused by the Coulomb factor of the electron assisted processes and by the effect of the crystal-lattice. The features of electron assisted heavy charged particle exchange processes, electron assisted nuclear capure processes and heavy charged particle assisted nuclear processes are also overviewed. Experimental observations, which may be related to our theoretical findings, are dealt with. The anomalous screening phenomenon is related to electron assisted neutron and proton exchange processes in crystalline solids. A possible explanation of observations by Fleischmann and Pons is presented. The possibility of the phenomenon of nuclear transmutation is qualitatively explained with the aid of usual and charged particle assisted reactions. The electron assisted neutron exchange processes in pure $N i$ and $L i - N i$ composite systems (in the Rossi-type E-Cat) are analyzed and it is concluded that these reactions may be responsible for recent experimental observations.
Comments:
arXiv admin note: text overlap with arXiv:1312.5498
Subjects:
physics.gen-ph (physics.gen-ph)
arXiv:
1502.01474 [pdf]
0 citations
02
[Submitted on 5 Feb 2015]
Relativistic density functional theory for finite nuclei and neutron stars
J. Piekarewicz
The main goal of the present contribution is a pedagogical introduction to the fascinating world of neutron stars by relying on relativistic density functional theory. Density functional theory provides a powerful--and perhaps unique--framework for the calculation of both the properties of finite nuclei and neutron stars. Given the enormous densities that may be reached in the core of neutron stars, it is essential that such theoretical framework incorporates from the outset the basic principles of Lorentz covariance and special relativity. After a brief historical perspective, we present the necessary details required to compute the equation of state of dense, neutron-rich matter. As the equation of state is all that is needed to compute the structure of neutron stars, we discuss how nuclear physics--particularly certain kind of laboratory experiments--can provide significant constrains on the behavior of neutron-rich matter.
Comments:
Contributing chapter to the book "Relativistic Density Functional for Nuclear Structure"; World Scientific Publishing Company (Singapore); Editor Prof. Jie Meng (Peking University)
Subjects:
Nuclear Theory (nucl-th); Solar and Stellar Astrophysics (astro-ph.SR); Nuclear Experiment (nucl-ex)
arXiv:
1502.01559 [pdf]
Int.Rev.Nucl.Phys.(2016)·2 citations
03
[Submitted on 5 Feb 2015]
Curvature correction term as a constraint for the Skyrme interaction
K. V. Cherevko · L. A. Bulavin · L. L. Jenkovszky · V. M. Sysoev · Feng-Shou Zhang
The curvature correction term to the surface tension is used as a criterion for the efficiency of the Skyrme interaction in describing surface properties. Based on the nuclear equation of state, the curvature correction term to the surface tension coefficient is calculated for 97 standard Skyrme interaction parameter sets in the vicinity of nuclear saturation density at zero temperature. The main idea is to find those parametrizations that give the Tolman's $δ$ correction close to the available theoretical predictions from the statistical theory. Only 59 out of 97 models give satisfactory results. Comparison of the obtained results with the results of the implementation of different macroscopic and microscopic constraints to Skyrme parametrizations available in the literature allows us to select 4 models that satisfy all the constraints.
Comments:
7 pages, 4 figures, 3 appendices
Subjects:
Nuclear Theory (nucl-th)
arXiv:
1502.01606 [pdf]
PRC(2015)·1 citation
04
[Submitted on 5 Feb 2015]
Description of the proton and neutron radiative capture reactions in the Gamow shell model
K. Fossez🇫🇷 · N. Michel🇫🇷 · M. Płoszajczak🇫🇷 · Y. Jaganathen🇺🇸 · R.M. Id Betan
We formulate the Gamow shell model (GSM) in coupled-channel (CC) representation for the description of proton/neutron radiative capture reactions and present the first application of this new formalism for the calculation of cross-sections in mirror reactions 7Be(p,gamma)8B and 7Li(n,gamma)8Li. The GSM-CC formalism is applied to a translationally-invariant Hamiltonian with an effective finite-range two-body interaction. Reactions channels are built by GSM wave functions for the ground state 3/2- and the first excited state 1/2- of 7Be/7Li and the proton/neutron wave function expanded in different partial waves.
Subjects:
Nuclear Theory (nucl-th)
arXiv:
1502.01631 [pdf]
PRC(2015)·47 citations
05
[Submitted on 5 Feb 2015]
The importance of the bulk viscosity of QCD in ultrarelativistic heavy-ion collisions
S. Ryu🇨🇦 · J.-F. Paquet🇨🇦 · C. Shen🇨🇦 · G. S. Denicol🇨🇦 · B. Schenke🇺🇸 · S. Jeon🇨🇦 · C. Gale🇨🇦
We investigate the consequences of a nonzero bulk viscosity coefficient on the transverse momentum spectra, azimuthal momentum anisotropy, and multiplicity of charged hadrons produced in heavy ion collisions at LHC energies. The agreement between a realistic 3D hybrid simulation and the experimentally measured data considerably improves with the addition of a bulk viscosity coefficient for strongly interacting matter. This paves the way for an eventual quantitative determination of several QCD transport coefficients from the experimental heavy ion and hadron-nucleus collision programs.
Comments:
5 pages, 3 figures. Light modifications to text and figures. To be published in PRL
Subjects:
Nuclear Theory (nucl-th); High Energy Physics — Phenomenology (hep-ph)
arXiv:
1502.01675 [pdf]
PRL(2015)·425 citations
06
[Submitted on 4 Feb 2015] (cross-list from hep-th)
Center symmetry and Hagedorn spectrum
Adi Armoni🇬🇧 · Thomas D. Cohen🇺🇸 · Srimoyee Sen🇺🇸
This paper explores the conjecture that large Nc gauge theories have a Hagedorn spectrum, if, and only if, they are confining and posses an explicit or emergent center symmetry. Evidence in support of this conjecture is presented. Many classes of large Nc gauge theories are considered. In all cases, we find that theories for which there exists a strong plausibility argument for a Hagedorn spectrum at large Nc are also believed to be confining and possess either an explicit center symmetric or have a strong plausibility argument for the existence of an emergent center symmetry at large Nc . Conversely, all theories we considered which are believed not to have a Hagedorn spectrum at large Nc, either were known not to be confining or else were believed to lack an emergent center symmetry. This is consistent with expectations based on the conjecture.
Comments:
expanded version. few references and one author added
Subjects:
High Energy Physics — Theory (hep-th); High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
1502.01356 [pdf]
PRD(2015)·4 citations
07
[Submitted on 5 Feb 2015] (cross-list from astro-ph.HE)
The effects of delta mesons on the baryonic direct Urca processes in neutron star matter
Xiu-Lin Huang · Hai-Jun Wang · Guang-Zhou Liu · Yan Xu
In the framework of relativistic mean field theory, the relativistic neutrino emissivity of the nucleonic and hyperonic direct Urca processes in the degenerate baryon matter of neutron stars are studied. We investigate particularly the influence of the isovector scalar interaction which is considered by exchanging $δ$ meson on the nucleonic and hyperonic direct Urca processes. The results indicate that $δ$ mesons lead to obvious enhancement of the total neutrino emissivity, which must result in more rapid cooling rate of neutron star matter.
Subjects:
High Energy Astrophysical Phenomena (astro-ph.HE); Nuclear Theory (nucl-th)
arXiv:
1502.01460 [pdf]
CPC(2015)·3 citations
08
[Submitted on 5 Feb 2015] (cross-list from cond-mat.mes-hall)
Generalized Bloch theorem and chiral transport phenomena
Naoki Yamamoto🇯🇵
Bloch theorem states the impossibility of persistent electric currents in the ground state of nonrelativistic fermion systems. We extend this theorem to generic systems based on the gauged particle number symmetry and study its consequences on the example of chiral transport phenomena. We show that the chiral magnetic effect can be understood as a generalization of the Bloch theorem to a nonequilibrium steady state, similarly to the integer quantum Hall effect. On the other hand, persistent axial currents are not prohibited by the Bloch theorem and they can be regarded as Pauli paramagnetism of relativistic matter. An application of the generalized Bloch theorem to quantum time crystals is also discussed.
Comments:
9 pages, 1 figure; v3: published version
Subjects:
Mesoscale and Nanoscale Physics (cond-mat.mes-hall); High Energy Physics — Theory (hep-th); Nuclear Theory (nucl-th); Quantum Physics (quant-ph)
arXiv:
1502.01547 [pdf]
PRD(2015)·116 citations
09
[Submitted on 5 Feb 2015] (cross-list from hep-ph)
Weak $K \to π$ generalized form factors and transverse transition quark-spin density from the instanton vacuum
Hyeon-Dong Son🇰🇷 · Seung-il Nam🇰🇷 · Hyun-Chul Kim🇰🇷
We investigate the generalized $K \to π$ transition vector and tensor form factors, from which we derive the transverse quark spin density in the course of the $K \to π$ transition, based on the nonlocal chiral quark model from the instanton vacuum. The results of the transition tensor form factor are in good agreement with recent data of lattice QCD. The behavior of the transverse quark spin density of the $K \to π$ transition turn out to be very similar to those of the pion and the kaon.
Comments:
11 pages, 5 figures. A few more sentences were added
Subjects:
High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Experiment (hep-ex); High Energy Physics — Lattice (hep-lat); Nuclear Theory (nucl-th)
arXiv:
1502.01558 [pdf]
PLB(2015)·7 citations
10
[Submitted on 5 Feb 2015] (cross-list from hep-ph)
Non-extensive statistics effects in transverse momentum spectra of hadrons
A.S. Parvan🇷🇺
The Bose-Einstein and Fermi-Dirac statistics of the identified hadrons were verified on the basis of the transverse momentum distributions of bosons and fermions created in the $pp$ collisions at high energies using the Tsallis-factorized statistics and the two-component distributions of the Boltzmann-Gibbs statistics. The main differences between the parameters of the Tsallis-factorized statistics and the Boltzmann-Gibbs statistics were identified. The results of the Boltzmann-Gibbs statistics are reasonable and suggest that the soft and hard hadrons may be produced from the two different macroscopic states of the dynamical system. It was revealed that the volume of the system obtained in the Tsallis-factorized statistics is unusually large in comparison with the geometrical volume of two protons. The main formulas for the Tsallis statistics in the grand canonical ensemble were formulated.
Comments:
2 figures
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
1502.01581 [pdf]
PoS(2015)·5 citations
11
[Submitted on 5 Feb 2015] (cross-list from hep-ph)
Heavy quark scattering and quenching in a QCD medium at finite temperature and chemical potential
H. Berrehrah🇩🇪 · E. Bratkovskaya🇩🇪 · W. Cassing🇩🇪 · P.B. Gossiaux🇫🇷 · J. Aichelin🇫🇷
The heavy quark collisional scattering on partons of the quark gluon plasma (QGP) is studied in a QCD medium at finite temperature and chemical potential. We evaluate the effects of finite parton masses and widths, finite temperature $T$ and quark chemical potential $μ_{q}$ on the different elastic cross sections for dynamical quasi-particles (on- and off-shell particles in the QGP medium as described by the dynamical quasi-particles model "DQPM") using the leading order Born diagrams. Our results show clearly the decrease of the $q Q$ and $g Q$ total elastic cross sections when the temperature and the quark chemical potential increase. These effects are amplified for finite $μ_{q}$ at temperatures lower than the corresponding critical temperature $T_{c} (μ_{q})$ . Using these cross sections we, furthermore, estimate the energy loss and longitudinal and transverse momentum transfers of a heavy quark propagating in a finite temperature and chemical potential medium. Accordingly, we have shown that the transport properties of heavy quarks are sensitive to the temperature and chemical potential variations. Our results provide some basic ingredients for the study of charm physics in heavy-ion collisions at Beam Energy Scan (BES) at RHIC and CBM experiment at FAIR.
Comments:
19 pages, 28 figures
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
1502.01700 [pdf]
PRC(2015)·20 citations

Affiliations

first authorsco-authorsvia INSPIRE