Nuclear Theory·nucl-th

Wednesday·December 17, 2014

11 papers—7 primary·4 cross-listed

01
[Submitted on 15 Dec 2014]
Bridging a gap between continuum-QCD and ab initio predictions of hadron observables
Daniele Binosi🇮🇹 · Lei Chang🇦🇺 · Joannis Papavassiliou🇪🇸 · Craig D. Roberts🇺🇸
Within contemporary hadron physics there are two common methods for determining the momentum-dependence of the interaction between quarks: the top-down approach, which works toward an ab initio computation of the interaction via direct analysis of the gauge-sector gap equations; and the bottom-up scheme, which aims to infer the interaction by fitting data within a well-defined truncation of those equations in the matter sector that are relevant to bound-state properties. We unite these two approaches by demonstrating that the renormalisation-group-invariant running-interaction predicted by contemporary analyses of QCD's gauge sector coincides with that required in order to describe ground-state hadron observables using a nonperturbative truncation of QCD's Dyson-Schwinger equations in the matter sector. This bridges a gap that had lain between nonperturbative continuum-QCD and the ab initio prediction of bound-state properties.
Comments:
6 pages, 2 figures, 1 table
Subjects:
Nuclear Theory (nucl-th); High Energy Physics — Lattice (hep-lat); High Energy Physics — Phenomenology (hep-ph); Nuclear Experiment (nucl-ex)
arXiv:
1412.4782 [pdf]
PLB(2015)·237 citations
02
[Submitted on 15 Dec 2014]
Charmed baryonic resonances in medium
Laura Tolos🇪🇸
We discuss the behavior of dynamically-generated charmed baryonic resonances in matter within a unitarized coupled-channel model consistent with heavy-quark spin symmetry. We analyze the implications for the formation of $D$ -meson bound states in nuclei and the propagation of $D$ mesons in heavy-ion collisions from RHIC to FAIR energies.
Comments:
8 pages, 5 figures, invited talk at Resonance Workshop at Catania (RS@CT), 3-7 November 2014, Catania (Italy)
Subjects:
Nuclear Theory (nucl-th); High Energy Physics — Phenomenology (hep-ph)
arXiv:
1412.4811 [pdf]
EPJ Web Conf.(2015)·1 citation
03
[Submitted on 16 Dec 2014]
Constraining nucleon strangeness
T. J. Hobbs🇺🇸 · Mary Alberg🇺🇸 · Gerald A. Miller🇺🇸
Determining the nonperturbative $s s ˉ$ content of the nucleon has attracted considerable interest and been the subject of numerous experimental searches. These measurements used a variety of reactions and place important limits on the vector form factors observed in parity-violating (PV) elastic scattering and the parton distributions determined by deep inelastic scattering (DIS). In spite of this progress, attempts to relate information obtained from elastic and DIS experiments have been sparse. To ameliorate this situation, we develop an interpolating model using light-front wave functions capable of computing both DIS and elastic observables. This framework is used to show that existing knowledge of DIS places significant restrictions on our wave functions. The result is that the predicted effects of nucleon strangeness on elastic observables are much smaller than those tolerated by direct fits to PV elastic scattering data alone. Using our model, we find $- 0.024 \leq μ_{s} \leq 0.035$ , and $- 0.137 \leq ρ_{s}^{D} \leq 0.081$ for the strange contributions to the nucleon magnetic moment and charge radius. The model we develop also independently predicts the nucleon's strange spin content $Δ s$ and scalar density $⟨ N ∣ s ˉ s ∣ N ⟩$ , and for these we find agreement with previous determinations.
Comments:
13 pages, 3 figures; updated to published version
Subjects:
Nuclear Theory (nucl-th); High Energy Physics — Phenomenology (hep-ph); Nuclear Experiment (nucl-ex)
arXiv:
1412.4871 [pdf]
PRC(2015)·21 citations
04
[Submitted on 16 Dec 2014]
Reexamination of the role of the $Δ^{*}$ resonances in the $pp \to n K^{+} Σ^{+}$ reaction
Xiao-Yun Wang🇨🇳 · Xu Cao🇨🇳 · Ju-Jun Xie🇨🇳 · Xu-Rong Chen🇨🇳
In this work, the role of the $Δ^{*}$ resonances in the process of $pp \to n K^{+} Σ^{+}$ are systematically investigated with the effective Lagrangian approach and the isobar model. We find that a $P_{31}$ state, either $Δ^{*} (1750)$ or $Δ^{*} (1910)$ , is favored by the data while the $P_{33}$ state, namely $Δ^{*} (1920)$ , has small contribution. Besides, either sub-threshold $S_{31}$ $Δ^{*} (1620)$ resonance or strong $n Σ$ final state interaction or both have possible contribution at near threshold region, depending on the measured cross sections. We demonstrate the invariant mass distributions and the Dalitz Plots in order to investigate whether it is possible to distinguish the controversial $K Σ$ production mechanism in these observables.
Comments:
10 pages, published version
Subjects:
Nuclear Theory (nucl-th)
arXiv:
1412.4895 [pdf]
PRC(2015)·7 citations
05
[Submitted on 16 Dec 2014]
Study of clustering structures through breakup reactions
Pierre Capel
Models for the description of breakup reactions used to study the structure of exotic cluster structures like halos are reviewed. The sensitivity of these models to the projectile description is presented. Calculations are sensitive to the projectile ground state mostly through its asymptotic normalisation coefficient (ANC). They also probe the continuum of the projectile. This enables studying not only the bound states of the projectile but also its continuum, both resonant and non-resonant. This opens the possibility to study correlations between both halo neutrons in two-neutron halo nuclei.
Comments:
Contribution to the proceedings of the 3rd international Workshop on "State of the Art in Nuclear Cluster Physics" (SotANCP, 26-30 May 2014, Yolohama, Japan). 7 pages, 6 figures
Subjects:
Nuclear Theory (nucl-th)
arXiv:
1412.4991 [pdf]
J.Phys.Conf.Ser.(2014)·0 citations
06
[Submitted on 16 Dec 2014]
Thermodynamics of pairing transition in hot nuclei
Lang Liu · Zhen-Hua Zhang · Peng-Wei Zhao
The pairing correlations in hot nuclei $^{162}$ Dy are investigated in terms of the thermodynamical properties by covariant density functional theory. The heat capacities $C_{V}$ are evaluated in the canonical ensemble theory and the paring correlations are treated by a shell-model-like approach, in which the particle number is conserved exactly. A S-shaped heat capacity curve, which agrees qualitatively with the experimental data, has been obtained and analyzed in details. It is found that the one-pair-broken states play crucial roles in the appearance of the S shape of the heat capacity curve. Moreover, due to the effect of the particle-number conservation, the pairing gap varies smoothly with the temperature, which indicates a gradual transition from the superfluid to the normal state.
Comments:
13 pages, 4 figures
Subjects:
Nuclear Theory (nucl-th); Nuclear Experiment (nucl-ex)
arXiv:
1412.5069 [pdf]
PRC(2015)·25 citations
07
[Submitted on 16 Dec 2014]
Separation of flow from chiral magnetic effect in U+U collisions using spectator asymmetry
Sandeep Chatterjee🇮🇳 · Prithwish Tribedy🇮🇳
We demonstrate that the prolate shape of the Uranium nucleus generates anti-correlation between spectator asymmetry and initial state ellipticity of the collision zone, providing a way to constrain the initial event shape in U+U collisions. As an application, we show that this can be used to separate the background contribution due to flow from the signals of chiral magnetic effect.
Comments:
5 pages, 4 figures, few texts modified
Subjects:
Nuclear Theory (nucl-th); High Energy Physics — Phenomenology (hep-ph); Nuclear Experiment (nucl-ex)
arXiv:
1412.5103 [pdf]
PRC(2015)·36 citations
08
[Submitted on 16 Dec 2014] (cross-list from hep-ph)
The Spinless Relativistic Kink-Like Problem
Wolfgang Lucha🇦🇹 · Franz F. Schöberl🇦🇹
We constrain the possible bound-state solutions of the spinless Salpeter equation (the most obvious semirelativistic generalization of the nonrelativistic Schrödinger equation) with an interaction between the bound-state constituents given by the kink-like potential (a central potential of hyperbolic-tangent form) by formulating a bunch of very elementary boundary conditions to be satisfied by all solutions of the eigenvalue problem posed by a bound-state equation of this type, only to learn that all results produced by a procedure very much liked by some quantum-theory practitioners prove to be in severe conflict with our expectations.
Comments:
8 pages
Subjects:
High Energy Physics — Phenomenology (hep-ph); Mathematical Physics (math-ph); math.MP (math.MP); Nuclear Theory (nucl-th); Quantum Physics (quant-ph)
arXiv:
1412.4950 [pdf]
Int.J.Mod.Phys.A(2015)·6 citations
09
[Submitted on 16 Dec 2014] (cross-list from hep-th)
Meson turbulence at quark deconfinement from AdS/CFT
Koji Hashimoto🇯🇵 · Shunichiro Kinoshita🇯🇵 · Keiju Murata🇯🇵 · Takashi Oka🇯🇵
Based on the QCD string picture at confining phase, we conjecture that the deconfinement transition always accompanies a condensation of higher meson resonances with a power-law behavior, "meson turbulence". We employ the AdS/CFT correspondence to calculate the meson turbulence for $N = 2$ supersymmetric QCD at large $N_{c}$ and at strong coupling limit, and find that the energy distribution to each meson level $n$ scales as $n^{α}$ with the universal scaling $α = - 5$ . The universality is checked for various ways to attain the quark deconfinement: a static electric field below/around the critical value, a time-dependent electric field quench, and a time-dependent quark mass quench, all result in the turbulent meson condensation with the universal power $α = - 5$ around the deconfinement.
Comments:
20 pages, 17 figures
Subjects:
High Energy Physics — Theory (hep-th); Strongly Correlated Electrons (cond-mat.str-el); General Relativity and Quantum Cosmology (gr-qc); High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
1412.4964 [pdf]
NPB(2015)·9 citations
10
[Submitted on 16 Dec 2014] (cross-list from hep-th)
Heavy Quark Potential at Finite Temperature in a Dual Gravity Closer to Large N QCD
Binoy Krishna Patra🇮🇳 · Himanshu Khanchandani🇮🇳
In gauge-gravity duality, the heavy quark potential at finite temperature is usually calculated with the pure AdS background, which does not capture the renormalization group (RG) running in the gauge theory part. In addition, the potential does not contain any confining term in the deconfined phase. Following the Klebanov-Strassler geometry, we employ a geometry, which captures the RG flow similar to QCD, to obtain the heavy quark potential by analytically continuing the string configurations into the complex plane. In addition to the attractive terms, the obtained potential has confining terms both at $T = 0$ and $T \neq = 0$ , compared to the calculations usually done in the literature, where only the Coulomb-like term is present in the deconfined phase. The potential also develops an (negative) imaginary part above a critical separation, $r_{c} (= 0.53 z_{h})$ . Moreover, our potential exhibits a behavior different from the usual Debye screening obtained from perturbation theory.
Comments:
18 pages, one figure; Typos corrected, replaced by published version
Subjects:
High Energy Physics — Theory (hep-th); High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
1412.5003 [pdf]
PRD(2015)·12 citations
11
[Submitted on 16 Dec 2014] (cross-list from hep-ph)
Gravity waves generated by sounds from big bang phase transitions
Tigran Kalaydzhyan🇺🇸 · Edward Shuryak🇺🇸
Inhomogeneities associated with the cosmological QCD and electroweak phase transitions produce hydrodynamical perturbations, longitudinal sounds and rotations. It has been demonstrated by Hindmarsh et al. that the sounds produce gravity waves (GW) well after the phase transition is over. We further argue that, under certain conditions, an inverse acoustic cascade may occur and move sound perturbations from the (UV) momentum scale at which the sound is originally produced to much smaller (IR) momenta. The weak turbulence regime of this cascade is studied via the Boltzmann equation, possessing stationary power and time-dependent self-similar solutions. We suggest certain indices for the strong turbulence regime as well, into which the cascade eventually proceeds. Finally, we point out that two on-shell sound waves can produce one on-shell gravity wave, and we evaluate the rate of the process using a standard sound loop diagram.
Comments:
13 pages. Published version
Subjects:
High Energy Physics — Phenomenology (hep-ph); Cosmology and Nongalactic Astrophysics (astro-ph.CO); High Energy Physics — Theory (hep-th); Nuclear Theory (nucl-th)
arXiv:
1412.5147 [pdf]
PRD(2015)·33 citations

Affiliations

first authorsco-authorsvia INSPIRE