Nuclear Theory·nucl-th

Wednesday·September 7, 2022

21 papers—12 primary·9 cross-listed

13
[Submitted on 2 Sept 2022] (cross-list from hep-ph)
Resumming Quark's Longitudinal Momentum Logarithms in LaMET Expansion of Lattice PDFs
Yushan Su🇺🇸 · Jack Holligan🇺🇸 · Xiangdong Ji🇺🇸 · Fei Yao🇨🇳 · Jian-Hui Zhang🇨🇳 · Rui Zhang🇺🇸
In the large-momentum expansion for parton distribution functions (PDFs), the natural physics scale is the longitudinal momentum ( $p_{z}$ ) of the quarks (or gluons) in a large-momentum hadron. We show how to expose this scale dependence through resumming logarithms of the type $ln^{n} p_{z} / μ$ in the matching coefficient, where $μ$ is a fixed renormalization scale. The result enhances the accuracy of the expansion at moderate $p_{z} > 1$ GeV, and at the same time, clearly shows that the partons cannot be approximated from quarks with $p_{z} \sim Λ_{QCD}$ which are not predominantly collinear with the parent hadron momentum, consistent with power counting of the large-momentum effective theory. The same physics mechanism constrains the coordinate space expansion at large distances $z$ , the conjugate of $p_{z}$ , as illustrated in the example of fitting the moments of the PDFs.
Comments:
17 pages, 9 figures
Subjects:
High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Lattice (hep-lat); Nuclear Theory (nucl-th)
arXiv:
2209.01236 [pdf]
NPB(2023)·62 citations
14
[Submitted on 3 Sept 2022] (cross-list from nucl-ex)
First Observation of Large Missing-Momentum (e,e'p) Cross-Section Scaling and the onset of Correlated-Pair Dominance in Nuclei
I. Korover · A.W. Denniston · A. Kiral · A. Schmidt · A. Lovato · N. Rocco · A. Nikolakopoulos · L.B. Weinstein · E. Piasetzky · O. Hen · the CLAS Collaboration
We report the first measurement of $x_{B}$ -scaling in $(e, e^{'} p)$ cross-section ratios off nuclei relative to deuterium at large missing-momentum of $350 \leq p_{mi ss} \leq 600$ MeV/c. The observed scaling extends over a kinematic range of $0.7 \leq x_{B} \leq 1.8$ , which is significantly wider than $1.4 \leq x_{B} \leq 1.8$ previously observed for inclusive $(e, e^{'})$ cross-section ratios. The $x_{B}$ -integrated cross-section ratios become constant (i.e., scale) beginning at $p_{mi ss} \approx k_{F}$ , the nuclear Fermi momentum. Comparing with theoretical calculations we find good agreement with Generalized Contact Formalism calculations for high missing-momentum ( $> 375$ MeV/c), suggesting the observed scaling results from interacting with nucleons in short-range correlated (SRC) pairs. For low missing-momenta, mean-field calculations show good agreement with the data for $p_{mi ss} \leq k_{F}$ , and suggest that contributions to the measured cross-section ratios from scattering off single, un-correlated, nucleons are non-negligible up to $p_{mi ss} \approx 350$ MeV/c. Therefore, SRCs become dominant in nuclei at $p_{mi ss} \approx 350$ MeV/c, well above the nuclear Fermi Surface of $k_{F} \approx 250$ MeV/c.
Comments:
7 pages, 4 figures and supplementary materials
Subjects:
Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
arXiv:
2209.01492 [pdf]
PRC(2023)·16 citations
15
[Submitted on 5 Sept 2022] (cross-list from hep-ph)
Possible origin of HADES data on proton number fluctuations in Au+Au collisions
O. Savchuk🇺🇦 · R. V. Poberezhnyuk🇺🇦 · M.I. Gorenstein🇺🇦
Recent data of the HADES Collaboration in Au+Au central collisions at $s_{NN} = 2.4$ GeV indicate large proton number fluctuations inside one unit of rapidity around midrapidity. This can be a signature of critical phenomena due to the strong attractive interactions between baryons. We study an alternative hypothesis that these large fluctuations are caused by the event-by-event fluctuations of the number of bare protons, and no interactions between these protons are assumed. The proton number fluctuations in five symmetric rapidity intervals $Δ y$ inside the region $Δ Y = 1$ are calculated using the binomial acceptance procedure. This procedure assumes the independent (uncorrelated) emission of protons, and it appears to be in agreement with the HADES data. To check this simple picture we suggest to calculate the correlation between proton multiplicities in non-overlapping rapidity intervals $Δ y_{1}$ and $Δ y_{2}$ placed inside $Δ Y = 1$ .
Comments:
5 pages, 2 figures
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
2209.01883 [pdf]
PLB(2022)·6 citations
16
[Submitted on 5 Sept 2022] (cross-list from nucl-ex)
The Core of $^{25}$ F studied by the $^{25}$ F(-1p) $^{24}$ O reaction
H. L. Crawford · M. D. Jones · A. O. Macchiavelli · P. Fallon · D. Bazin · P. C. Bender · B. A. Brown · C. M. Campbell · R. M. Clark · M. Cromaz · B. Elman · A. Gade and 10 other authors
The $^{25}$ F( $5/ 2^{+}) (- 1 p)^{24}$ O reaction was studied at the NSCL using the S800 spectrometer. The experimental spectroscopic factor for the ground-state to ground-state transition indicates a substantial depletion of the proton $d_{5/2}$ strength compared to shell-model expectations. Our result supports the findings reported by Tang \textit{et al.}, from their study of the $(p, 2 p)$ reaction at RIBF. The overlap between the $^{25}$ F and $^{24}$ O ground-states is considerably less than anticipated if $^{24}$ O acted as a robust and rigid doubly-magic core in $^{25}$ F. We interpret the results within the framework of the Particle-Vibration Coupling (PVC) of a $d_{5/2}$ proton coupled to a quadrupole phonon of an effective core. This approach provides a good description of the experimental data by requiring an effective $^{24}$ O* core with a phonon energy of $ℏ ω_{2}$ = 3.2 MeV, and a $B (E 2) 2.7$ W.u., softer and more collective than a bare $^{24}$ O. Both the Nilsson deformed mean field and the PVC models appear to capture the properties of the effective core of $^{25}$ F, suggesting that the additional proton tends to polarize the free, doubly magic $^{24}$ O in such a way that it becomes either slightly deformed or a quadrupole vibrator.
Comments:
6 pages, 2 figures
Subjects:
Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
arXiv:
2209.02162 [pdf]
0 citations
17
[Submitted on 6 Sept 2022] (cross-list from hep-ph)
Anisotropic pressure of magnetized quark matter with anomalous magnetic moment
Nilanjan Chaudhuri🇮🇳 · Snigdha Ghosh🇮🇳 · Pradip Roy🇮🇳 · Sourav Sarkar🇮🇳
We investigate magnetic field $(e B)$ dependence of constituent quark mass, the longitudinal and transverse pressure as well as the magnetization and magnetic susceptibility of strongly interacting quark matter. We employ the two-flavour Polyakov Nambu--Jona-Lasinio model with the inclusion of the anomalous magnetic moment (AMM) of the quarks at finite temperature $(T)$ and finite quark chemical potential $(μ_{q})$ capturing different stages of chiral phase transition. We find that the transverse pressure, magnetization and magnetic susceptibility become highly oscillatory for large values of $e B$ in the chiral symmetry broken phase. However the oscillations cease to occur at higher values of $T$ and $μ_{q}$ when chiral symmetry is (partially) restored and the anisotropic nature of the pressure becomes significant even at smaller values of $e B$ . As the inclusion of AMM of the quarks leads to inverse magnetic catalysis of the transition temperature we observe that the variations of transverse pressure, magnetization and magnetic susceptibility are significantly modified in the vicinity of the chiral transition temperature. Furthermore, above the chiral transition temperature the magnetic susceptibility is found to remain positive for a wide range of $e B$ indicating a paramagnetic character of the strongly interacting quark matter. Finally, we have also examined the magnetism of strongly interacting matter in the quarkyonic phase. The obtained results could be useful for a magnetohydrodynamic evolution of hot and dense matter created in heavy-ion collisions.
Comments:
Version Published in Physical Review D
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
2209.02248 [pdf]
PRD(2022)·22 citations
18
[Submitted on 6 Sept 2022] (cross-list from hep-ph)
Quark-model relations among TMDs in the parton model
F. Aslan🇺🇸 · S. Bastami🇺🇸 · A. Mahabir🇺🇸 · A. Tandogan🇺🇸 · P. Schweitzer🇺🇸
The covariant parton model (CPM) is a consequent application of the parton model concept to the nucleon structure. In this model, there is a choice to put quarks either in a pure-spin state or in a mixed-spin state. We show that the mixed-spin version of the CPM does not support the quark-model relations among transverse momentum dependent parton distributions (TMDs) which were shown to hold in a large class of quark models. One can enforce the quark-model relations to be valid in the CPM by imposing a condition which is equivalent to putting the quarks in a pure-spin state. This gives a complementary perspective on the connection of the pure- and mixed-spin state CPM versions, and provides a fresh view on the question whether the quark-model relations could be realized in QCD as "approximate relations" with some useful numerical accuracy.
Comments:
v1: 10 pages. v2: reformatted, 11 pages
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
2209.02355 [pdf]
PRD(2022)·4 citations
19
[Submitted on 6 Sept 2022] (cross-list from hep-ph)
Cross-channel constraints on resonant antikaon-nucleon scattering
Jun-Xu Lu🇨🇳 · Li-Sheng Geng🇨🇳 · Michael Doering🇺🇸 · Maxim Mai🇺🇸
Chiral perturbation theory and its unitarized versions have played an important role in our understanding of the low-energy strong interaction. Yet, so far, such studies typically deal exclusively with perturbative or nonperturbative channels. In this letter, we report on the first global study of meson-baryon scattering up to one-loop order. It is shown that covariant baryon chiral perturbation theory, including its unitarization for the negative strangeness sector, can describe meson-baryon scattering data remarkably well. This provides a highly non-trivial check on the validity of this important low-energy effective field theory of QCD. We show that the $K ˉ N$ related quantities can be better described in comparison with those of lower-order studies, and with reduced uncertainties due to the stringent constraints from the $π N$ and $K N$ phase shifts. In particular, we find that the two-pole structure of $Λ (1405)$ persists up to one-loop order reinforcing the existence of two-pole structures in dynamically generated states.
Comments:
11 pages, 3 figures; to appear in Physical Review Letters
Subjects:
High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Experiment (hep-ex); Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
arXiv:
2209.02471 [pdf]
PRL(2023)·60 citations
20
[Submitted on 6 Sept 2022] (cross-list from astro-ph.HE)
Effects of nuclear matter and composition in core-collapse supernovae and long-term proto-neutron star cooling
Kohsuke Sumiyoshi · Shun Furusawa · Hiroki Nagakura · Akira Harada · Hajime Togashi · Ken'ichiro Nakazato · Hideyuki Suzuki
We study the influence of hot and dense matter in core-collapse supernovae by adopting up-to-date nuclear equation of state (EOS) based on the microscopic nuclear many-body frameworks. We explore effects of EOS based on the Dirac Brueckner Hartree-Fock theory through comparisons with those based on the variational method. We also examine effects of the differences in the composition of nuclei and nucleons by using the same EOS by the variational method but employing two different treatments in computations of nuclear abundances. We perform numerical simulations of core-collapse supernovae adopting the three EOSs. We also perform numerical simulations of the long-term evolution over 70 s of the proto-neutron star cooling. We show that impacts by different modeling of composition are remarkable as in those by different treatments of uniform matter in the gravitational collapse, bounce, and shock propagation. The cooling of proto-neutron star and the resulting neutrino emission are also affected by the compositional difference even if the same treatment in computing uniform matter of EOS.
Comments:
33 pages, 23 figures, 1 table, accepted for publication in Progress of Theoretical and Experimental Physics (PTEP)
Subjects:
High Energy Astrophysical Phenomena (astro-ph.HE); Nuclear Theory (nucl-th)
arXiv:
2209.02474 [pdf]
PTEP(2023)·10 citations
21
[Submitted on 6 Sept 2022] (cross-list from physics.atom-ph)
Synthesis of cold and trappable fully stripped HCI's via antiproton-induced nuclear fragmentation in traps
G. Kornakov (1) · G. Cerchiari (2) · J. Zieliński (1) · L. Lappo (1) · G. Sadowski (3) · M. Doser (3) ((1) Warsaw University of Technology · (2) Institut für Experimentalphysik Universität Innsbruck · (3) CERN)
The study of radioisotopes as well as of highly charged ions is a very active and dynamic field. In both cases, the most sensitive probes involve species trapped in Penning or Paul traps after a lengthy series of production and separation steps that limit the types and lifetimes of species that can be investigated. We propose a novel production scheme that forms fully (or almost fully) stripped radionuclei in form of highly charged ions (HCI's) directly in the trapping environment. The method extends the range of species, among them radioisotopes such as $^{21}$ F, $^{100}$ Sn or $^{229}$ Th, that can be readily produced and investigated and is complementary to existing techniques.
Comments:
9 pages, 6 figures
Subjects:
Atomic Physics (physics.atom-ph); Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
arXiv:
2209.02596 [pdf]
PRC(2023)·8 citations

Affiliations

first authorsco-authorsvia INSPIRE