Nuclear Theory·nucl-th

Monday·December 21, 2020

12 papers—4 primary·8 cross-listed

05
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.
↳ nucl-exnucl-thPLB(2021)·11 citations
06
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.
↳ hep-phhep-exnucl-thPRD(2021)·52 citations
07
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.
↳ nucl-exhep-phnucl-th6 citations
08
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.
↳ hep-phnucl-exnucl-thPRC(2021)·51 citations
09
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.
↳ astro-ph.HEnucl-thEur.Phys.J.ST(2021)·15 citations
10
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.
↳ hep-phhep-exnucl-thPRC(2021)·3 citations
11
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.
↳ hep-phhep-exnucl-exnucl-thEPJA(2021)·11 citations
12
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.
↳ astro-ph.HEnucl-thMNRAS(2021)·32 citations

Affiliations

first authorsco-authorsvia INSPIRE