Nuclear Theory·nucl-th

Monday·December 21, 2020

12 papers—4 primary·8 cross-listed

01
[Submitted on 17 Dec 2020]
$P$ -wave dibaryon resonances in $pp$ elastic scattering and near-threshold pion production
O.A. Rubtsova🇷🇺 · V.I. Kukulin🇷🇺 · M.N. Platonova🇷🇺
It is demonstrated within the dibaryon-induced model for $N N$ interaction that $pp$ scattering in $P$ waves is governed mainly by the production of the intermediate dibaryon resonances. Two dibaryon resonances with a mass of about 2200 MeV discovered recently by the ANKE-COSY Collaboration are shown to determine both elastic $pp$ phase shifts and inelasticities in the $^{3} P_{0}$ and $^{3} P_{2}$ - $^{3} F_{2}$ channels from zero energy up to $T_{p} = 0.7$ - $0.9$ GeV. It is also demonstrated clearly that the $^{3} P_{0}$ dibaryon plays a decisive role in near-threshold neutral pion production in $pp$ collisions which is poorly understood to date. The missing dibaryon contribution is found to be the very possible reason for the failure of traditional approaches to explain near-threshold $π^{0}$ production.
Comments:
12 pages, 11 figures; version accepted for publication in PRD
Subjects:
Nuclear Theory (nucl-th); High Energy Physics — Phenomenology (hep-ph)
arXiv:
2012.09886 [pdf]
PRD(2020)·6 citations
02
[Submitted on 17 Dec 2020]
CFNS Ad-Hoc meeting on Radiative Corrections Whitepaper
Andrei Afanasev · Jaseer Ahmed · Igor Akushevich · Jan C. Bernauer · Peter G. Blunden · Andrea Bressan · Duane Byer · Ethan Cline · Markus Diefenthaler · Jan M. Friedrich · Haiyan Gao · Alexandr Ilyichev and 16 other authors
Current precision scattering experiments and even more so many experiments planed for the Electron Ion Collider will be limited by systematics. From the theory side, a fundamental source of systematic uncertainty is the correct treatment of radiative effects. To gauge the current state of technique and knowledge, help the cross-pollination between different direction of nuclear physics, and to give input to the yellow report process, the community met in an ad-hoc workshop hosted by the Center for Frontiers in Nuclear Science, Stony Brook University. This whitepaper is a collection of contributions to this workshop.
Subjects:
Nuclear Theory (nucl-th)
arXiv:
2012.09970 [pdf]
6 citations
03
[Submitted on 18 Dec 2020]
Enhanced production of strange baryons in high energy nuclear collisions from a multiphase transport model
Tianhao Shao🇨🇳 · Jinhui Chen🇨🇳 · Che Ming Ko🇺🇸 · Zi-Wei Lin🇺🇸
We introduce additional coalescence factors for the production of strange baryons in a multiphase transport (AMPT) model in order to describe the enhanced production of multistrange hadrons observed in Pb-Pb collisions at $s_{NN}$ = 2.76 TeV at the Large hadron Collider (LHC) and Au+Au collisions at $s_{NN}$ = 200 GeV at Relativistic Heavy-Ion Collider (RHIC).This extended AMPT model is found to also give a reasonable description of the multiplicity dependence of the strangeness enhancement observed in high multiplicity events in $pp$ collisions at $s$ = 7 TeV and $p$ -Pb collisions at $s_{NN}$ = 5.02 TeV. We find that the coalescence factors depend on the system size but not much on whether the system is produced from A+A or p+A collisions. The extended AMPT model thus provides a convenient way to model the mechanism underlying the observed strangeness enhancement in collisions of both small and large systems at RHIC and LHC energies.
Comments:
15 pages, 5 figures
Subjects:
Nuclear Theory (nucl-th); Nuclear Experiment (nucl-ex)
arXiv:
2012.10037 [pdf]
PRC(2020)·25 citations
04
[Submitted on 18 Dec 2020]
A benchmark of initial state models for heavy-ion collisions at $s_{_{NN}} =$ 27 and 62 GeV
Jakub Cimerman · Iurii Karpenko · Boris Tomášik · Barbara Antonina Trzeciak
Description of relativistic heavy-ion collisions at the energies of RHIC Beam Energy Scan program with fluid dynamic approach poses several challenges, one of which being a complex geometry and a longer duration of the pre-hydrodynamic stage. Therefore, existing fluid dynamic models for heavy-ion collisions at the RHIC Beam Energy Scan energies rely on rather complex initial states, such as UrQMD cascade or multi-fluid dynamics. In this study, we show that functionally simpler, non-dynamical initial states can be employed for the fluid dynamical simulations of Au-Au collisions at $\mbox{$ \sqrt{s_{_{\rm NN}}} $}=27$ and 62.4~GeV. We adapt the initial states based on Monte Carlo Glauber model (GLISSANDO 2) and $T_{A} T_{B}$ ansatz based on reduced thickness (T $_{R}$ ENTo $p = 0$ ), extended into the longitudinal direction and finite baryon density. We find that both initial states, when coupled to a 3D event-by-event viscous fluid dynamic + cascade model, result in an overall fair reproduction of basic experimental data: pseudorapidity distributions, transverse momentum spectra and elliptic flow, at both collision energies. This is a rather surprising, given that the $T_{A} T_{B}$ ansatz is functionally similar to the EKRT and IP-Glasma models, which are successful at much larger energies and rely on a partonic picture of the initial state.
Comments:
13 pages, 14 figures, version accepted for publication in Phys.Rev.C
Subjects:
Nuclear Theory (nucl-th); Nuclear Experiment (nucl-ex)
arXiv:
2012.10266 [pdf]
PRC(2021)·12 citations
05
[Submitted on 17 Dec 2020] (cross-list from nucl-ex)
On the $β$ -decay of $^{186}$ Hg
A. Algora🇪🇸 · E. Ganioğlu🇹🇷 · P. Sarriguren🇪🇸 · V.Guadilla🇪🇸 · L. M. Fraile🇪🇸 · E. Nácher🇪🇸 · B. Rubio🇪🇸 · J. L. Tain🇪🇸 · J. Agramunt🇪🇸 · W. Gelletly🇬🇧 · J. A. Briz🇪🇸 · R. B. Cakirli🇹🇷 and 11 other authors
The Gamow-Teller strength distribution of the decay of $^{186}$ Hg into $^{186}$ Au has been determined for the first time using the total absorption gamma spectroscopy technique and has been compared with theoretical QRPA calculations using the SLy4 Skyrme force. The measured Gamow-Teller strength distribution and the half-life are described by mixing oblate and prolate configurations independently in the parent and daughter nuclei. The best description of the experimental beta strength is obtained with dominantly prolate components for both parent $^{186}$ Hg and daughter $^{186}$ Au. The approach also allowed us to determine an upper limit of the oblate component in the parent state. The complexity of the analysis required the development of a new approach in the analysis of the X-ray gated total absorption spectrum.
Comments:
12 pages, 5 figures
Subjects:
Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
arXiv:
2012.09878 [pdf]
PLB(2021)·11 citations
06
[Submitted on 17 Dec 2020] (cross-list from hep-ph)
Probing the Weinberg Operator at Colliders
Benjamin Fuks🇫🇷 · Jonas Neundorf🇩🇪 · Krisztian Peters🇩🇪 · Richard Ruiz🇧🇪 · Matthias Saimpert🇨🇭
Motivated by searches for $0 ν β β$ decay in nuclear experiments and collider probes of lepton number violation at dimension $d \geq 7$ , we investigate the sensitivity to the $d = 5$ Weinberg operator using the non-resonant signature $pp \to ℓ^{\pm} ℓ^{' \pm} j j$ at the LHC. We develop a prescription for the operator that is applicable in collisions and decays, and focus on the $ℓ ℓ^{'} = μμ$ channel, which is beyond the reach of nuclear decays. For a Wilson coefficient $C_{5}^{μμ} = 1$ , scales as heavy as $Λ \sim 8.3 (11)$ ~TeV can be probed with $L = 300 fb^{- 1} (3 ab^{- 1})$ . This translates to an effective $μμ$ Majorana mass of $∣ m_{μμ} ∣ \sim 7.3 (5.4)$ ~GeV, and establishes a road map for testing the Weinberg operator at accelerators.
Comments:
Journal version. 9 pages including an extended technical appendix; 4 figures; 4 tables; UFO models available from https://feynrules.irmp.ucl.ac.be/wiki/SMWeinberg
Subjects:
High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Experiment (hep-ex); Nuclear Theory (nucl-th)
arXiv:
2012.09882 [pdf]
PRD(2021)·52 citations
07
[Submitted on 17 Dec 2020] (cross-list from nucl-ex)
The reactor antineutrino spectrum calculation
S. V. Silaeva🇷🇺 · V. V. Sinev🇷🇺
New fissile isotopes antineutrino spectra ( $^{235}$ U, $^{238}$ U, $^{239}$ Pu and $^{241}$ Pu) calculation is presented. On base of summation method the toy model was developed. It was shown that total antineutrino number is conserved in framework of given database on individual fragments yields. The analysis of antineutrino spectrum shape says that any presented antineutrino spectrum should satisfy to the total antineutrino number conservation.
Comments:
9 pages, 5 figures, 6 tables
Subjects:
Nuclear Experiment (nucl-ex); High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
2012.09917 [pdf]
6 citations
08
[Submitted on 17 Dec 2020] (cross-list from hep-ph)
Particlization of an interacting hadron resonance gas with global conservation laws for event-by-event fluctuations in heavy-ion collisions
Volodymyr Vovchenko🇺🇸 · Volker Koch🇺🇸
We revisit the problem of particlization of a QCD fluid into hadrons and resonances at the end of the fluid dynamical stage in relativistic heavy-ion collisions in a context of fluctuation measurements. The existing methods sample an ideal hadron resonance gas, therefore, they do not capture the non-Poissonian nature of the grand-canonical fluctuations, expected due to QCD dynamics such as the chiral transition or QCD critical point. We address the issue by partitioning the particlization hypersurface into locally grand-canonical fireballs populating the space-time rapidity axis that are constrained by global conservation laws. The procedure allows to quantify the effect of global conservation laws, volume fluctuations, thermal smearing and resonance decays on fluctuation measurements in various rapidity acceptances, and can be used in fluid dynamical simulations of heavy-ion collisions. As a first application, we study event-by-event fluctuations in heavy-ion collisions at the LHC using an excluded volume hadron resonance gas model matched to lattice QCD susceptibilities, with a focus on (pseudo)rapidity acceptance dependence of net baryon, net proton, and net charge cumulants. We point out large differences between net proton and net baryon cumulant ratios that make direct comparisons between the two unjustified. We observe that the existing experimental data on net-charge fluctuations at the LHC shows a strong suppression relative to a hadronic description.
Comments:
25 pages, 9 figures
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
arXiv:
2012.09954 [pdf]
PRC(2021)·51 citations
09
[Submitted on 18 Dec 2020] (cross-list from astro-ph.HE)
New equation of state involving Bose-Einstein condensate of antikaon for supernova and neutron star merger simulations
Tuhin Malik🇮🇳 · Sarmistha Banik🇮🇳 · Debades Bandyopadhyay🇮🇳
We compute a new equation of state table including Bose-Einstein condensate of $K^{-}$ mesons for core collapse supernova and neutron star merger simulations. Nuclei and interacting nucleons in non-uniform matter is described in an extended version of the nuclear statistical equilibrium model including excluded volume effects whereas the uniform matter at higher densities is treated in the relativistic hadron field theory with density dependent couplings. The equation of state table is generated for a wide range of density ( $1 0^{- 12}$ to $\sim 1$ fm $^{- 3}$ ), positive charge fraction (0.01 to 0.60) and temperature (0.1 to 158.48 MeV). The impact of antikaon condensate is investigated on different thermodynamic quantities for example free energy per baryon, entropy per baryon, pressure as well as compositions of matter. Furthermore, critical temperatures of antikaon condensation and the phase diagram of matter are also studied in this article.
Comments:
Accepted for publication in EPJ ST
Subjects:
High Energy Astrophysical Phenomena (astro-ph.HE); Nuclear Theory (nucl-th)
arXiv:
2012.10127 [pdf]
Eur.Phys.J.ST(2021)·15 citations
10
[Submitted on 18 Dec 2020] (cross-list from hep-ph)
Relativistic mean-field corrections for interactions of dark matter particles with nucleons
X. G. Wang🇦🇺 · A. W. Thomas🇦🇺
We investigate the interactions of weakly interacting massive particles (WIMPS) with nucleons in nuclear medium by taking into account the effect of nuclear dynamics. We derive the nonrelativistic effective operators starting from the relativistic mean-field approximation. Certain interactions receive non-negligible corrections, which may significantly change the sensitivities of WIMP-nucleus scattering cross section to these effective operators.
Comments:
9 pages, 1 table
Subjects:
High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Experiment (hep-ex); Nuclear Theory (nucl-th)
arXiv:
2012.10144 [pdf]
PRC(2021)·3 citations
11
[Submitted on 18 Dec 2020] (cross-list from hep-ph)
Dependence of related parameters on centrality and mass in a new treatment for transverse momentum spectra in high energy collisions
Pei-Pin Yang🇨🇳 · Mai-Ying Duan🇨🇳 · Fu-Hu Liu🇨🇳
We collected the experimental data of transverse momentum spectra of identified particles produced in proton-proton ( $p$ - $p$ ), deuteron-gold ( $d$ -Au or $d$ - $A$ ), gold-gold (Au-Au or $A$ - $A$ ), proton-lead ( $p$ -Pb or $p$ - $A$ ), and lead-lead (Pb-Pb or $A$ - $A$ ) collisions measured by the ALICE, CMS, LHCb, NA49, NA61/SHINE, PHENIX, and STAR collaborations at different center-of mass energies. The multisource thermal model at the quark level or the participant quark model is used to describe the experimental data. The free parameters, the effective temperature $T$ , entropy index-related $n$ , and revised index $a_{0}$ , in the revised Tsallis--Pareto-type function are extracted at the quark level. In most cases, $T$ and $n$ in central collisions are larger than those in peripheral collisions, and $a_{0}$ does not change in different centrality classes. With the increase in the mass of produced particle or participant quark, $T$ and $a_{0}$ increase, and $n$ does not change significantly. The behaviors of related parameters from $p$ - $p$ , $p (d)$ - $A$ , and $A$ - $A$ collisions are similar.
Comments:
34 pages, 16 figures. The European Physical Journal A, accepted
Subjects:
High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Experiment (hep-ex); Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
arXiv:
2012.10228 [pdf]
EPJA(2021)·11 citations
12
[Submitted on 18 Dec 2020] (cross-list from astro-ph.HE)
Resonant Shattering Flares as Multimessenger Probes of the Nuclear Symmetry Energy
Duncan Neill · William G. Newton · David Tsang
The behaviour of the nuclear symmetry energy near saturation density is important for our understanding of dense nuclear matter. This density dependence can be parameterised by the nuclear symmetry energy and its derivatives evaluated at nuclear saturation density. In this work we show that the core-crust interface mode of a neutron star is sensitive to these parameters, through the (density-weighted) shear-speed within the crust, which is in turn dependent on the symmetry energy profile of dense matter. We calculate the frequency at which the neutron star quadrupole ( $ℓ = 2$ ) crust-core interface mode must be driven by the tidal field of its binary partner to trigger a Resonant Shattering Flare (RSF). We demonstrate that coincident multimessenger timing of an RSF and gravitational wave chirp from a neutron star merger would enable us to place constraints on the symmetry energy parameters that are competitive with those from current nuclear experiments.
Comments:
15 pages, 19 figures, accepted in MNRAS
Subjects:
High Energy Astrophysical Phenomena (astro-ph.HE); Nuclear Theory (nucl-th)
arXiv:
2012.10322 [pdf]
MNRAS(2021)·32 citations

Affiliations

first authorsco-authorsvia INSPIRE