Nuclear Theory·nucl-th

Friday·November 11, 2022

7 papers—2 primary·5 cross-listed

01
[Submitted on 10 Nov 2022]
Skin values of $^{208}$ Pb and $^{48}$ Ca determined from reaction cross sections (published in Results in Physics)
Tomotsugu Wakasa · Shingo Tagami · Masanobu Yahiro
The PREX and the CREX group reported their skin values. Using the Love-Franey (LF) $t$ -matrix folding model with the neutron and proton densities scaled to the neutron radius $r_{n}^{208} (PREX2)$ and the proton radius of the electron scattering, we found that the model reproduces $σ_{R}$ for p+ $^{208}$ Pb scattering at $E_{lab} = 534.1, 549, 806$ MeV. Zenihiro {\it el al. } deduce neutron radii $r_{n}^{48, 40} (exp)$ from proton elastic scattering, whereas we determine $r_{m}^{40} (exp) = 3.361 \pm 0.075$ fm from measured $σ_{R}$ for $^{4}$ He+ $^{40}$ Ca scattering. Our first aim is to determine $r_{skin}^{208}$ from measured $σ_{R}$ of p+ $^{208}$ Pb scattering at $E_{lab} = 534.1, 549, 806$ MeV by using the LF $t$ -matrix folding model. Our second aim is to determine $r_{skin}^{48}$ from the $r_{m}^{40} (exp)$ and $Δ \equiv r_{m}^{48} (exp) - r_{m}^{40} (exp)$ that is evaluated from the $r_{n}^{48, 40} (exp)$ and the $r_{p}^{48, 40} (exp)$ calculated with the isotope shift method based on the electron scattering. For the first aim, we use the LF $t$ -matrix model with the densities scaled from the D1S-GHFB+AMP neutron density. The D1M-GHFB+AMP is used to estimate a theoretical error. The resulting skin values are $r_{skin}^{208} = 0.324 \pm 0.047$ fm for D1S and $r_{skin}^{208} (exp) = 0.333 \pm 0.047$ fm for D1M. The $Δ = 0.109$ fm and $r_{m}^{40} (exp) = 3.361 \pm 0.075$ fm yield $r_{m}^{48} = 3.470 \pm 0.075$ fm, leading to $r_{skin}^{48} = 0.144 \pm 0.075$ fm. We conclude that $r_{skin}^{208} (exp) = 0.324 \pm (0.047)_{exp} \pm (0.009)_{th} fm$ for p scattering at $E_{lab} = 534.1, 549, 806$ MeV. Our skin values are consistent with the PREX2 and CREX values.
Comments:
4 pages, 1 figure
Subjects:
Nuclear Theory (nucl-th); Nuclear Experiment (nucl-ex)
arXiv:
2211.05312 [pdf]
0 citations
02
[Submitted on 10 Nov 2022]
Structure and reaction study of Z=120 isotopes using non-relativistic and relativistic mean-field formalism
Jeet Amrit Pattnaik · K. C. Naik · R. N. Panda · M. Bhuyan · S. K. Patra
An extensive study is carried out for the island of stability in the superheavy nuclei of Z=120 and N=164-220 within the effective field theory motivated relativistic mean-field (E-RMF) and the non-relativistic Skyrme-Hartree-Fock (SHF) approaches. The relativistic G3 and IOPB-I and non-relativistic SLy4 and SkMP parameter sets are used for the investigations. Surface properties such as symmetry energy, neutron pressure and the curvature coefficient of symmetry energy are discussed within the coherent density fluctuation model (CDFM) using the Skyrme and the Brückner energy density functionals. The volume and surface contributions of symmetry energy are evaluated using Danielewicz's liquid drop approximation within the CDFM. The total nuclear reaction and elastic differential cross-sections are also obtained for both SHF and E-RMF within the Glauber model. The peaks in the symmetry energy at N = 182 for SHF and N=184 for E-RMF are seen, which are absent in the Brückner functional. The shifting of peak in the symmetry energy with Brückner functional can be correlated to the Coester-band problem. The enhanced total reaction cross-section for relativistic density of $^{304} 120$ suggests the extra stability of this nucleus. This further confirms the shell/sub-shell closure of N = 184 in E-RMF force. The differential cross-section shows its force independent nature and significant increase with the scattering angle.
Comments:
13 pages, 9 figures, 1 table
Subjects:
Nuclear Theory (nucl-th)
arXiv:
2211.05671 [pdf]
Pramana(2023)·9 citations
03
[Submitted on 9 Nov 2022] (cross-list from gr-qc)
Reverse phase transitions in binary neutron-star systems with exotic-matter cores
Maximiliano Ujevic🇧🇷 · Henrique Gieg🇧🇷 · Federico Schianchi🇩🇪 · Swami Vivekanandji Chaurasia🇸🇪 · Ingo Tews🇺🇸 · Tim Dietrich🇩🇪
Multi-messenger observations of binary neutron star mergers provide a unique opportunity to constrain the dense-matter equation of state. Although it is known from quantum chromodynamics that hadronic matter will undergo a phase transition to exotic forms of matter, e.g., quark matter, the onset density of such a phase transition cannot be computed from first principles. Hence, it remains an open question if such phase transitions occur inside isolated neutron stars or during binary neutron star mergers, or if they appear at even higher densities that are not realized in the Cosmos. In this article, we perform numerical-relativity simulations of neutron-star mergers and investigate scenarios in which the onset density of such a phase transition is exceeded in at least one inspiralling binary component. Our simulations reveal that shortly before the merger it is possible that such stars undergo a "reverse phase transition", i.e., densities decrease and the quark core inside the star disappears leaving a purely hadronic star at merger. After the merger, when densities increase once more, the phase transition occurs again and leads, in the cases considered in this work, to a rapid formation of a black hole. We compute the gravitational-wave signal and the mass ejection for our simulations of such scenarios and find clear signatures that are related to the post-merger phase transition, e.g., smaller ejecta masses due to the softening of the equation of state through the quark core formation. Unfortunately, we do not find measurable imprints of the reverse phase transition.
Comments:
12 pages, 9 figures
Subjects:
General Relativity and Quantum Cosmology (gr-qc); High Energy Astrophysical Phenomena (astro-ph.HE); Nuclear Theory (nucl-th)
arXiv:
2211.04662 [pdf]
PRD(2023)·22 citations
04
[Submitted on 9 Nov 2022] (cross-list from hep-ph)
Mueller's dipole wave function in QCD: emergent KNO scaling in the double logarithm limit
Yizhuang Liu🇵🇱 · Maciej A. Nowak🇵🇱 · Ismail Zahed🇺🇸
We analyze Mueller's QCD dipole wave function evolution in the double logarithm approximation (DLA). Using complex analytical methods, we show that the distribution of dipole in the wave function (gluon multiplicity distribution) asymptotically satisfies the Koba-Nielsen-Olesen (KNO) scaling, with a non-trivial scaling function $f (z)$ with $z = \frac{n}{n ˉ}$ . The scaling function decays exponentially as $2 (2.55)^{2} z e^{- \frac{z}{0.3917}}$ at large $z$ , while its growth is log-normal as $e^{- \frac{1}{2} l n^{2} z}$ for small- $z$ . A detailed analysis of the Fourier-Laplace transform of $f (z)$ , allows for performing the inverse Fourier transform, and access the non-asymptotic bulk-region around the peak. The bulk and asymptotic results are shown to be in good agreement with the measured hadronic multiplicities in DIS, as reported by the H1 collaboration at HERA in the region of large $Q^{2}$ . A numerical tabulation of $f (z)$ is included. Remarkably, the same scaling function is found to emerge in the resummation of double logarithms in the evolution of jets. Using the generating function approach, we show why this is the case. The absence of KNO scaling in non-critical and super-renormalizable theories is briefly discussed. We also discuss the universal character of the entanglement entropy in the KNO scaling limit, and its measurement using the emitted multiplicities in DIS and $e^{+} e^{-}$ annihilation.
Comments:
36 pages, 10 figures, 2 tables
Subjects:
High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Theory (hep-th); Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
arXiv:
2211.05169 [pdf]
PRD(2023)·24 citations
05
[Submitted on 10 Nov 2022] (cross-list from hep-ph)
The proton radius and its relatives -- much ado about nothing?
Ulf-G. Meißner🇩🇪
I summarize the dispersion-theoretical analysis of the nucleon electromagnetic form factors. Special emphasis is given on the extraction of the proton charge radius and its relatives, the proton magnetic radius as well as the neutron magnetic radius. Some recent work on the hyperfine splitting in leptonic hydrogen and on radiative corrections to muon-proton scattering is also discussed. Some views on future studies are given.
Comments:
9 pages, 7 figures, plenary talk at INPC 2022, Cape Town, South Africa. arXiv admin note: text overlap with arXiv:2208.04025
Subjects:
High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Experiment (hep-ex); High Energy Physics — Lattice (hep-lat); Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
arXiv:
2211.05419 [pdf]
J.Phys.Conf.Ser.(2023)·9 citations
06
[Submitted on 10 Nov 2022] (cross-list from hep-ph)
Hydrodynamization in hybrid Bjorken flow attractors
Toshali Mitra🇮🇳 · Sukrut Mondkar🇮🇳 · Ayan Mukhopadhyay🇮🇳 · Anton Rebhan🇦🇹 · Alexander Soloviev🇦🇹
Hybrid fluid models, consisting of two sectors with more weakly and more strongly self-interacting degrees of freedom coupled consistently as in the semi-holographic framework, have been shown to exhibit an attractor surface for Bjorken flow. Retaining only the simple viscid fluid descriptions of both sectors, we find that, on the attractor surface, the hydrodynamization times of both subsectors decrease with increasing total energy density at the respective point of hydrodynamization following a conformal scaling, reach their minimum values, and subsequently rise rapidly. The minimum values are obtained when the respective energy densities are of the order of the inverse of the dimensionful inter-system coupling. Restricting to attractor curves which can be matched to glasma models at a time set by the saturation scale for both $p$ - $p$ and Pb-Pb collisions, we find that the more weakly coupled sector hydrodynamizes much later, and the strongly coupled sector hydrodynamizes earlier in $p$ - $p$ collisions, since the total energy densities at the respective hydrodynamization times of these sectors fall inside and outside of the conformal window. This holds true also for phenomenologically relevant solutions that are significantly away from the attractor surface at the time we match to glasma models.
Comments:
50 pages, 19 figures. Version to appear in JHEP; Section 4 improved
Subjects:
High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Theory (hep-th); Nuclear Theory (nucl-th)
arXiv:
2211.05480 [pdf]
JHEP(2024)·8 citations
07
[Submitted on 10 Nov 2022] (cross-list from hep-ph)
Phenomenological description of the $π^{-} π^{+}$ $S$ -waves in $D^{+} \to π^{-} π^{+} π^{+}$ and $D_{s}^{+} \to π^{-} π^{+} π^{+}$ decays: The problem of phases
N.N. Achasov🇷🇺 · G.N. Shestakov🇷🇺
We present a phenomenological description of the LHCb data for the magnitudes and phases of the $π^{-} π^{+}$ $S$ -wave amplitudes in the $D^{+} \to π^{-} π^{+} π^{+}$ and $D_{s}^{+} \to π^{-} π^{+} π^{+}$ decays. We operate within a simple model that takes into account the known pair interactions of particles in coupled channels. The seed complex amplitudes for various intermediate state production are assumed to be independent of the energy. Their values are determined by fitting. This model gives the satisfactorily description of virtually all features of the energy dependence of the experimentally measured $S$ -wave amplitudes in the $D^{+} \to π^{-} π^{+} π^{+}$ and $D_{s}^{+} \to π^{-} π^{+} π^{+}$ decays in the regions $2 m_{π} < m_{π^{-} π^{+}} < 1.39 \mbox G e V$ and $2 m_{π} < m_{π^{-} π^{+}} < 1.29 \mbox G e V$ , respectively.
Comments:
9 pages, 6 figures; v2: published version; clarifications, references, and comment on possibility of pi-eta S-wave phase shift measurement added
Subjects:
High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Experiment (hep-ex); Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
arXiv:
2211.05526 [pdf]
PRD(2023)·3 citations

Affiliations

first authorsco-authorsvia INSPIRE

Skin values of 208Pb and 48Ca determined from reaction cross sections (published in Results in Physics)

Structure and reaction study of Z=120 isotopes using non-relativistic and relativistic mean-field formalism

Reverse phase transitions in binary neutron-star systems with exotic-matter cores

Mueller's dipole wave function in QCD: emergent KNO scaling in the double logarithm limit

The proton radius and its relatives -- much ado about nothing?

Hydrodynamization in hybrid Bjorken flow attractors

Phenomenological description of the π−π+ S-waves in D+→π−π+π+ and Ds+​→π−π+π+ decays: The problem of phases

Affiliations

Skin values of $^{208}$ Pb and $^{48}$ Ca determined from reaction cross sections (published in Results in Physics)

Phenomenological description of the $π^{-} π^{+}$ $S$ -waves in $D^{+} \to π^{-} π^{+} π^{+}$ and $D_{s}^{+} \to π^{-} π^{+} π^{+}$ decays: The problem of phases