Nuclear Theory·nucl-th

Monday·November 26, 2018

20 papers—15 primary·5 cross-listed

01
[Submitted on 22 Nov 2018]
E-by-e jet suppression, anisotropy, medium response and hard-soft tomography
Yayun He (CCNU)🇨🇳 · Shanshan Cao (WSU)🇺🇸 · Wei Chen (CCNU)🇨🇳 · Tan Luo (CCNU)🇨🇳 · Long-Gang Pang (UCB & LBNL)🇺🇸 · Xin-Nian Wang (CCNU & LBNL)🇨🇳
The Linear Boltzmann Transport (LBT) model for jet propagation and interaction in quark-gluon plasma (QGP) has been used to study jet quenching in high-energy heavy-lion collisions. The suppression of single inclusive jet production, medium modification of $γ$ -jet correlation, jet profiles and fragmentation functions as observed in experiments at Large Hadron Collider (LHC) can be described well by LBT in which jet-induced medium response is shown to play an essential role. In event-by-event simulations of jet quenching within LBT, jet azimuthal anisotropies are found to correlate linearly with the anisotropic flows of bulk hadrons from the underlying hydrodynamic events.
Comments:
4 pages, 6 figures, Parallel talk presented at QM2018
Subjects:
Nuclear Theory (nucl-th); High Energy Physics — Phenomenology (hep-ph)
arXiv:
1811.08975 [pdf]
NPA(2019)·3 citations
02
[Submitted on 22 Nov 2018]
An Elementary End of the Periodic Table
Yang-Hui He🇬🇧 · Stavros Garoufalidis🇺🇸
Using the Planck scale as an absolute bound of half-life, we give a quick estimate, in the manner of Feynman's fine-structure method, of the highest possible atomic number. We find, upon simple extrapolation, that element 168 would constitute the end of the Periodic Table and its isotope with atomic weight 411, being the most stable. These are remarkably close to current best estimates obtained from sophisticated and much more involved Hartree-Fock calculations.
Comments:
3 pages, 1 figure
Subjects:
Nuclear Theory (nucl-th); High Energy Physics — Theory (hep-th)
arXiv:
1811.08978 [pdf]
0 citations
03
[Submitted on 22 Nov 2018]
Energy dependence of the $K ˉ N$ interaction and the two-pole structure of the $Λ (1405)$ -- are they real?
János Révai
It is shown, that the energy dependence of the chiral based $K ˉ N$ potentials, responsible for the ocurence of two poles in the $I = 0$ sector is the consequence of applying the on-shell factorization approximation [1]. When the dynamical equation is solved without this approximation, the $T$ -matrix has only one pole in the region of the $Λ (1405)$ resonance.
Comments:
Submitted to proceedings of the 22nd International Conference on Few-body Problems in Physics (Caen, France, July 9-13, 2018)
Subjects:
Nuclear Theory (nucl-th)
arXiv:
1811.09039 [pdf]
Springer Proc.Phys.(2020)·1 citation
04
[Submitted on 22 Nov 2018]
The nucleon effective mass and its isovector splitting
Tuhin Malik · C. Mondal · B. K. Agrawal · J.N. De · S.K. Samaddar
Using an energy density functional (EDF) based on the thermodynamic Gibbs-Duhem relation, found equivalent to the standard Skyrme EDF for infinite nuclear matter, it is demonstrated that the parameters of this EDF are not uniquely determined from the fit of the empirical and theoretical data related to nuclear matter. This prevents an unambiguous determination of the nucleon effective mass ( $\frac{m _{0}^{*}}{m}$ ) and its isovector splitting ( $Δ m_{0}^{*}$ ). Complementary information from dipole polarizability of atomic nuclei helps in removing this ambiguity and plausible values of $\frac{m _{0}^{*}}{m}$ and $Δ m_{0}^{*}$ can be arrived at. Presently considered fit data on infinite nuclear matter and dipole polarizability of finite nuclei yield $\frac{m _{0}^{*}}{m} = 0.68 \pm 0.04$ and $Δ m_{0}^{*} = (- 0.20 \pm 0.09) δ$ . This EDF is consistent with the constraint on the maximum mass of the neutron star.
Comments:
9 pages, 6 figures, accepted as a regular article in Phys. Rev. C
Subjects:
Nuclear Theory (nucl-th)
arXiv:
1811.09077 [pdf]
PRC(2018)·10 citations
05
[Submitted on 22 Nov 2018]
Nucleon Parton Distribution Amplitude: A scalar diquark picture
Cédric Mezrag🇮🇹 · Jorge Segovia🇪🇸 · Minghui Ding🇺🇸 · Lei Chang🇨🇳 · Craig D. Roberts🇺🇸
We report progress on the development of Perturbative Integral Representation Ansätze to compute the nucleon Faddeev Wave function, using an explicit quark-diquark picture. Our formalism is able to handle non-pointlike diquark and to mimic the strong, dynamical correlations observed when solving the Faddeev Equation. We then project the wave function in order to compute the leading-twist Parton Distribution Amplitude.
Comments:
6 pages, 2 figures, contribution to the proceedings of the XXII International Conference on Few-Body Problems in Physics (FB22) 2018, July 9-13, Caen, France
Subjects:
Nuclear Theory (nucl-th); High Energy Physics — Phenomenology (hep-ph)
arXiv:
1811.09104 [pdf]
Springer Proc.Phys.(2020)·2 citations
06
[Submitted on 22 Nov 2018]
Advanced statistical methods to fit nuclear models
M. Shelley · P.Becker · A.Gration · A. Pastore
We discuss advanced statistical methods to improve parameter estimation of nuclear models. In particular, using the Liquid Drop Model for nuclear binding energies, we show that the area around the global $χ^{2}$ minimum can be efficiently identified using Gaussian Process Emulation. We also demonstrate how Markov-chain Monte-Carlo sampling is a valuable tool for visualising and analysing the associated multidimensional likelihood surface.
Subjects:
Nuclear Theory (nucl-th)
arXiv:
1811.09130 [pdf]
Acta Phys.Polon.Supp.(2019)·7 citations
07
[Submitted on 22 Nov 2018]
Asymptotic theory of charged particle transfer reactions at low energies and nuclear astrophysics
R. Yarmukhamedov · K. I. Tursunmakhatov · N. Burtebayev
A new asymptotic theory is proposed for the peripheral sub- and above-barrier transfer $A$ ( $x$ , $y$ ) $B$ reaction within the three-body ( $A$ , $a$ and $y$ ) model, where $x$ = $y$ + $a$ , $B$ = $A$ + $a$ and $a$ is a transferred particle. In the asymptotic theory, the allowance of the contribution of the three-body ( $A$ , $a$ and $y$ ) Coulomb dynamics of the transfer mechanism to the peripheral partial amplitudes for the partial wave $l_{i} >>$ 1 and of the Coulomb-nuclear distorted effects in the entrance and exit channels is done in a correct manner within the framework of the dispersion theory and the conventional distorted-wave Born approximation (DWBA), respectively. It is shown that the proposed asymptotic theory makes it possible to test the accuracy of taking into account the the three-body Coulomb dynamics of the transfer mechanism in the modified DWBA. The results of the analysis of the differential cross sections of the specific proton and triton transfer reactions at above- and sub-barrier energies are presented. New estimates and their uncertainties are obtained for values of the asymptotic normalization coefficients for $^{9} Be + p \to^{10} B$ , $^{11} B + p \to^{12} C$ , $^{16} O + p \to^{17} F$ and $^{19} F \to^{16} O + t$ as well as for the direct astrophysical $S$ factors at stellar energy of the radiative capture $^{9} Be (p, γ)^{10} B$ , $^{11} B (p, γ)^{12} C$ and $^{16} O (p, γ)^{17} F$ reactions.
Subjects:
Nuclear Theory (nucl-th)
arXiv:
1811.09175 [pdf]
Int.J.Mod.Phys.Conf.Ser.(2019)·1 citation
08
[Submitted on 23 Nov 2018]
Hadron gas with repulsive mean field
Pasi Huovinen🇵🇱 · Peter Petreczky🇺🇸
We study the QCD equation of state, and fluctuations of baryon number and strangeness using the hadron resonance gas model with repulsive mean field. We find that including both the predicted but not observed resonances, a.k.a. missing states, and the repulsive mean field into the resonance gas model leads to better description of the lattice results. The repulsive mean field is particularly important for the higher order baryon number fluctuations.
Comments:
8 pages, Proceedings of "XIII Quark Confinement and the Hadron Spectrum - Confinement2018", 31 July - 6 August 2018, Maynooth University, Ireland
Subjects:
Nuclear Theory (nucl-th); High Energy Physics — Lattice (hep-lat); High Energy Physics — Phenomenology (hep-ph)
arXiv:
1811.09330 [pdf]
PoS(2018)·1 citation
09
[Submitted on 23 Nov 2018]
Model Dependence of the Pion Form Factor Extracted from Pion Electro-production
Robert J. Perry🇦🇺 · Ayse Kızılersu🇦🇺 · Anthony W. Thomas🇦🇺
In 2008 the Jefferson Laboratory $F_{π}$ Collaboration released results for the pion electromagnetic form factor, which they extracted from pion electro-production data. The measured values for the pion form factor are model dependent, and require the use of the Vanderhaeghen, Guidal and Laget Regge Model for their extraction. While agreement between this model and data is impressive, the theoretical implementation of gauge invariance is less satisfying. We would like to establish how well the extracted form factor corresponds to the true form factor. To do this, we use a simple toy model, which imposes gauge invariance in a more theoretically satisfying way. The model form factor is extracted from our model cross section using the method employed by the $F_{π}$ Collaboration to extract the experimental pion form factor. We conclude that the reconstructed model form factor is a reasonable representation of the true model form factor for the kinematics chosen, although we note that the extracted form factor is smaller than the true form factor. This suggests that current extracted values of pion form factor may be overestimated.
Comments:
13 pages
Subjects:
Nuclear Theory (nucl-th); High Energy Physics — Phenomenology (hep-ph)
arXiv:
1811.09356 [pdf]
PRC(2019)·10 citations
10
[Submitted on 23 Nov 2018]
Extended optical model analyses of $^{11}$ Be+ $^{197}$ Au with dynamic polarization potentials
Kyoungsu Heo · Myung-Ki Cheoun · Ki-Seok Choi · K. S. Kim · W. Y. So
We discuss angular distributions of elastic, inelastic, and breakup cross sections for $^{11}$ Be + $^{197}$ Au system, which were measured at energies below and around Coulomb barrier. To this end, we employ Coulomb dipole excitation (CDE) and long-range nuclear (LRN) potential to take into account long range effects by halo nuclear system and break up effects by weakly-bound structure. We then analyze recent experimental data including 3-channes i.e. elastic, inelastic, and breakup cross sections, at $E_{c.m.}$ =29.6 MeV and $E_{c.m.}$ =37.1 MeV. From the extracted parameter sets using $χ^{2}$ analysis, we successfully reproduce the experimental angular distributions of the elastic, inelastic, and breakup cross sections for $^{11}$ Be+ $^{197}$ Au system simultaneously. Also we discuss the necessity of LRN potential around Coulomb barrier from analyzed experimental data.
Subjects:
Nuclear Theory (nucl-th)
arXiv:
1811.09360 [pdf]
EPJA(2020)·3 citations
11
[Submitted on 23 Nov 2018]
Shell model results for nuclear $β^{-}$ -decay properties of $s d$ shell nuclei
Anil Kumar · Praveen C. Srivastava · Toshio Suzuki
We evaluate the allowed $β^{-}$ -decay properties of nuclei with $Z = 8 - 15$ systematically under the framework of the nuclear shell model with the use of the valence space Hamiltonians derived from modern $ab in t i o$ methods, such as in-medium similarity renormalization group and coupled-cluster theory. For comparison we also show results obtained with fitted interaction derived from the chiral effective field theory and phenomenological USDB interaction. We have performed calculations for O $\to$ F, F $\to$ Ne, Ne $\to$ Na, Na $\to$ Mg, Mg $\to$ Al, Al $\to$ Si, Si $\to$ P and P $\to$ S transitions. Theoretical results of $B (GT)$ , log $f t$ values and half-lives, are discussed and compared with the available experimental data.
Comments:
11 pages, 15 figures, 2 tables, Accepted version in Progress of Theoretical and Experimental Physics (2020).[The Physical Society of Japan]
Subjects:
Nuclear Theory (nucl-th); Nuclear Experiment (nucl-ex)
arXiv:
1811.09367 [pdf]
PTEP(2020)·11 citations
12
[Submitted on 23 Nov 2018]
Short-range three-nucleon interaction from A=3 data and its hierarchical structure
L. Girlanda · A. Kievsky · M. Viviani · L. E. Marcucci
We construct accurate models of three-nucleon (3N) interaction by fitting, in a hybrid phenomenological approach, the low-energy constants parametrizing the subleading 3N contact operators to the triton binding energy, n-d scattering lengths, cross section and polarization observables of p-d scattering at 2 MeV center-of-mass energy. These models lead to a satisfactory description of polarized p-d scattering data in the whole energy range below the deuteron breakup threshold. In particular, the long-standing $A_{y}$ puzzle seems to be solved thanks to the new terms considered in the 3N force. Two types of hierarchies among the subleading contact operators are also derived, based on the large- $N_{c}$ counting and on a recently proposed relativistic counting. We test these hierarchies against the same experimental data and show that they are respected at a reasonable level.
Comments:
35 pages, 9 figures
Subjects:
Nuclear Theory (nucl-th)
arXiv:
1811.09398 [pdf]
PRC(2019)·43 citations
13
[Submitted on 23 Nov 2018]
The problem of cluster separability in relativistic few-body systems
Wolfgang Schweiger · Nikita Reichelt · William H. Klink
An appropriate framework for dealing with hadron structure and hadronic physics in the few-GeV energy range is relativistic quantum mechanics. The Bakamjian-Thomas construction provides a systematic procedure for implementing interactions in a relativistic invariant way. It leads, however, to problems with cluster separability. It has been known for some time, due to Sokolov's pioneering work, that mass operators with correct cluster properties can be obtained through a series of unitary transformations making use of so-called packing operators. In the present contribution we sketch an explicit construction of packing operators for three-particle systems consisting of distinguishable, spinless particles.
Comments:
4 pages, contribution presented by W. Schweiger at the 22nd International Conference on Few-Body Problems in Physics (Caen, July 9-13, 2018)
Subjects:
Nuclear Theory (nucl-th)
arXiv:
1811.09405 [pdf]
Springer Proc.Phys.(2020)·0 citations
14
[Submitted on 23 Nov 2018]
Camouflage of the Phase Transition to Quark Matter in Neutron Stars
Wei Wei🇨🇳 · Bryen Irving🇺🇸 · Thomas Klähn🇺🇸 · Prashanth Jaikumar🇺🇸
It has been known for some time that compact stars containing quark matter can masquerade as neutron stars in the range of measured mass and radius, making it difficult to draw firm conclusions on the phases of matter present inside the star. Using the vector-enhanced Bag model (vBag), we examine mass-radius and mass-compactness relations with Maxwell and Gibbs construction for hybrid stars with transitions from nuclear matter to two or three-flavor quark matter, including sequential transitions. Not only can stable hybrid stars with either two or three-flavor quark matter mimic neutron stars (the traditional masquerade), it appears as well difficult to distinguish two-flavor from three-flavor quark matter even in cases where a phase transition can be said to have occurred, as in the presence of a distinct kink in the mass-radius relation. Furthermore, allowing for sequential flavor transitions, we find that the transition into an unstable branch can be caused by either a transition from a nuclear to unstable quark matter or the sequential transition from nuclear to stable but "masquerading" two-flavor to unstable three-flavor quark matter. Addressing chiral restoration as well as quark deconfinement in a model of the phase transition, as the vBag does, adds further flexibility to the high-density equation of state, motivating caution in using even high-precision $M$ - $R$ data to draw firm conclusions on the nature of phases and phase transitions in neutron stars.
Comments:
10 pages, 5 figure panels
Subjects:
Nuclear Theory (nucl-th)
arXiv:
1811.09441 [pdf]
27 citations
15
[Submitted on 23 Nov 2018]
Universal scaling of the sigma field and net-protons from Langevin dynamics of model A
Shanjin Wu🇨🇳 · Zeming Wu🇨🇳 · Huichao Song🇨🇳
In this paper, we investigate the Kibble-Zurek scaling of the sigma field and net-protons within the framework of Langevin dynamics of model A. After determining the characteristic scales $τ_{k z}, l_{k z}$ and $θ_{k z}$ and properly rescaling the traditional cumulants, we construct universal functions for the sigma field and approximate universal functions for net-protons in the critical regime, which are insensitive to the relaxation time and the chosen evolving trajectory. Besides, the oscillating behavior for the higher order cumulants of net-protons near the critical point is also drastically suppressed, which converge into approximate universal curves with these constructed Kibble-Zurek functions.
Subjects:
Nuclear Theory (nucl-th)
arXiv:
1811.09466 [pdf]
PRC(2019)·27 citations
16
[Submitted on 12 Nov 2018] (cross-list from hep-ph)
Second-Order Leptonic Radiative Corrections for Lepton-Proton Scattering
R.-D. Bucoveanu🇩🇪 · H. Spiesberger🇩🇪
The interpretation of high-precision lepton-nucleon scattering experiments requires the knowledge of higher-order radiative corrections. We present a calculation of the cross section for unpolarized lepton-proton scattering including leptonic radiative corrections up to second order, including one- and two-loop corrections, radiation of one and two photons and one-loop corrections for one-photon radiation. Numerical results are given for the planned P2 experiment at the MESA facility in Mainz, and some results are also discussed for Qweak and the suggested MUSE experiment.
Comments:
28 pages
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
1811.04970 [pdf]
EPJA(2019)·34 citations
17
[Submitted on 21 Nov 2018] (cross-list from astro-ph.HE)
Hypermassive Neutron Star Disk Outflows and Blue Kilonovae
Steven Fahlman · Rodrigo Fernández
We study mass ejection from accretion disks around newly-formed hypermassive neutron stars (HMNS). Standard kilonova model fits to GW170817 require at least a lanthanide-poor ('blue') and lanthanide-rich ('red') component. The existence of a blue component has been used as evidence for a HMNS remnant of finite lifetime, but average disk outflow velocities from existing long-term HMNS simulations fall short of the inferred value ( $\sim 0.25 c$ ) by a factor of $\sim 2$ . Here we use time-dependent, axisymmetric hydrodynamic simulations of HMNS disks to explore the limits of the model and its ability to account for observations. For physically plausible parameter choices compatible with GW170817, we find that hydrodynamic models that use shear viscosity to transport angular momentum cannot eject matter with mass-averaged velocities larger than $\sim 0.15 c$ . While outflow velocities in our simulations can exceed the asymptotic value for a steady-state neutrino-driven wind, the increase in the average velocity due to viscosity is not sufficient. Therefore, viscous HMNS disk winds cannot reproduce by themselves the ejecta properties inferred from multi-component fits to kilonova light curves from GW170817. Three possible resolutions remain feasible within standard merger ejecta channels: more sophisticated radiative transfer models that allow for photon reprocessing between ejecta components, inclusion of magnetic stresses, or enhancement of the dynamical ejecta. We provide fits to our disk outflow models once they reach homologous expansion.
Comments:
Accepted by ApJ letters
Subjects:
High Energy Astrophysical Phenomena (astro-ph.HE); Solar and Stellar Astrophysics (astro-ph.SR); General Relativity and Quantum Cosmology (gr-qc); Nuclear Theory (nucl-th)
arXiv:
1811.08906 [pdf]
ApJL(2018)·49 citations
18
[Submitted on 21 Nov 2018] (cross-list from hep-ph)
Model-independent femtoscopic Levy imaging for elastic proton-proton scattering
T. Csorgo🇨🇭 · R. Pasechnik🇸🇪 · A. Ster🇭🇺
A model independent Levy expansion method is introduced to describe nearly Levy shaped squared moduli of Fourier transforms. We apply this method to precisely characterize the most recent elastic scattering data of proton-proton collisions at $s = 13$ TeV. The results reveal a substructure of protons, which is found to be significantly larger and darker in high energy proton-proton collisions at the TeV scale, as compared to a rather faint and apparently overlooked sub-structure, that we also identify in elastic proton-proton scattering at the ISR energy range of $s = 23 - 62$ GeV.
Comments:
8 pages, 2x2 figures, 2 Tables. Invited talk of T. Csorgo at WPCF 2019 at JINR, Dubna, Russia, submitted to the proceedings. Physics of Elementary Particles and Nuclei (PEPAN), in press
Subjects:
High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Experiment (hep-ex); Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th); Data Analysis, Statistics and Probability (physics.data-an)
arXiv:
1811.08913 [pdf]
Phys.Part.Nucl.(2020)·8 citations
19
[Submitted on 22 Nov 2018] (cross-list from hep-ph)
Exclusive $ρ$ and $J /Ψ$ photoproduction in ultraperipheral $p A$ collisions: Predictions of the gluon saturation models for the momentum transfer distributions
V. P. Goncalves🇧🇷 · F. S. Navarra🇧🇷 · D. Spiering🇧🇷
In this letter we complement previous studies on exclusive vector meson photoproduction in hadronic collisions presenting a comprehensive analysis of the $t$ - spectrum measured in exclusive $ρ$ and $J /Ψ$ photoproduction in $p A$ collisions at the LHC. We compute the differential cross sections considering two phenomenological models for the gluon saturation effects and present predictions for $pP b$ and $pC a$ collisions. Moreover, we compare our predictions with the recent preliminary CMS data for the exclusive $ρ$ photoproduction. We demonstrate that the gluon saturation models are able to describe the CMS data at small - $t$ . On the other hand, the models underestimate the few data point at large -- $t$ . Our results indicate that future measurements of the large -- $t$ region can be useful to probe the presence or absence of a dip in the $t$ -- spectrum and discriminate between the different approaches to the gluon saturation effects.
Comments:
6 pages, 4 figures
Subjects:
High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Experiment (hep-ex); Nuclear Theory (nucl-th)
arXiv:
1811.09124 [pdf]
PLB(2019)·32 citations
20
[Submitted on 13 Nov 2018] (cross-list from hep-ph)
Centrality and Transverse momentum dependencies of Hadrons in Xe+Xe collisions at $s_{N N} = 5.44$ TeV from a multi-phase transport model
Lilin Zhu🇨🇳 · Hua Zheng🇨🇳 · Ruimin Kong
In this paper, we study and predict the charged-particle pseudorapidity multiplicity density ( $\frac{d N _{c h}}{d η}$ ), transverse momentum spectra of identified particles and their ratios in relativistic heavy ion collisions at the Large Hadron Collider (LHC), using the string-melting version of a multi-phase transport (AMPT) model with improved quark coalescence method. Results of the charged-particle pseudorapidity multiplicity density from AMPT model calculations for Pb+Pb collisions at $s_{N N} = 5.02$ TeV are compared with the experimental data. Good agreements are generally found between theoretical calculations and experimental data. We predict $\frac{d N _{c h}}{d η}$ for Xe+Xe collisions at $s_{N N} = 5.44$ TeV at different centralities, and $p_{T}$ spectra of charged pions, kaons and protons, and their ratios $K / π$ and $p / π$ in Pb+Pb collisions at $s_{N N} = 5.02$ TeV and Xe+Xe collisions at $s_{N N} = 5.44$ TeV that are being studied at LHC. The $p_{T}$ spectra of identified particles in Pb+Pb collisions from the improved AMPT model are compared and found to be consistent with results from the iEBE-VISHNU hybrid model with TRENTo initial condition.
Comments:
6 pages, 5 figures
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
1811.09510 [pdf]
EPJA(2019)·12 citations

Affiliations

first authorsco-authorsvia INSPIRE