Wed·Feb 28, 2024Wednesday·February 28, 2024

1. 01*

   On the significance of radiative corrections on measurements of the EMC effect

   S. Moran🇺🇸 · M. Arratia🇺🇸 · J. Arrington🇺🇸 · D. Gaskell🇺🇸 · B. Schmookler🇺🇸

   Analyzing global data on the EMC effect, which denotes differences in parton distribution functions in nuclei compared to unbound nucleons, reveals tensions. Precise measurements at Jefferson Lab, studying both x and A dependence, show systematic discrepancies among experiments, making the extraction of the A dependence of the EMC effect sensitive to the selection of datasets. By comparing various methods and assumptions used to calculate radiative corrections, we have identified differences that, while not large, significantly impact the EMC ratios and show that using a consistent radiative correction procedure resolves this discrepancy, leading to a more coherent global picture, and allowing for a more robust extraction of the EMC effect for infinite nuclear matter.

   nucl-exPRC(2024)·3 citations
2. 02*

   $K_S^0$ meson production in inelastic p+p interactions at 31, 40 and 80 GeV/c beam momentum measured by NA61/SHINE at the CERN SPS

   N. Abgrall🇨🇭 · H. Adhikary🇵🇱 · P. Adrich🇵🇱 · K.K. Allison🇺🇸 · N. Amin🇩🇪 · E.V. Andronov · T. Antičić🇭🇷 · I.-C. Arsene🇳🇴 · M. Bajda🇵🇱 · Y. Balkova🇵🇱 · M. Baszczyk🇵🇱 · D. Battaglia🇺🇸 and 146 other authors

   Measurements of $K_S^0$ meson production via its ${\pi }^{+}{\pi }^{-}$ decay mode in inelastic $\text{p+p}$ interactions at incident projectile momenta of 31, 40 and 80 GeV/$c$ ($\sqrt{s_{NN}}=7.7,8.8$ and $12.3$ GeV, respectively) are presented. The data were recorded by the NA61/SHINE spectrometer at the CERN Super Proton Synchrotron. Double-differential distributions were obtained in transverse momentum and rapidity. The mean multiplicities of $K_S^0$ mesons were determined to be $(5.95\pm 0.19(stat)\pm 0.22(sys))\times 10^{-2}$ at 31 GeV/$c$, $(7.61\pm 0.13(stat)\pm 0.31(sys))\times 10^{-2}$ at 40 GeV/$c$ and $(11.58\pm 0.12(stat)\pm 0.37(sys))\times 10^{-2}$ at 80 GeV/$c$. The results on $K_S^0$ production are compared with model calculations (Epos1.99, SMASH 2.0 and PHSD) as well as with published data from other experiments.

   ↳ hep-exnucl-exEPJC(2024)·7 citations
3. 03*

   Estimation of electric field in intermediate-energy heavy-ion collisions

   Hidetoshi Taya🇯🇵 · Toru Nishimura🇯🇵 · Akira Ohnishi🇯🇵

   We estimate the spacetime profile of the electric field in head-on heavy-ion collisions at intermediate collision energies $\sqrt{s_{\mathrm{NN}}}=\mathcal{O}(3-10\mathrm{GeV})$. Using a hadronic cascade model (JAM; Jet AA Microscopic transport model), we numerically demonstrate that the produced field has strength $eE=\mathcal{O}((30-60\mathrm{MeV}{)}^2)$, which is supercritical to the Schwinger limit of QED and is non-negligibly large compared even to the hadron/QCD scale, and survives for a long time $\tau =\mathcal{O}(10\mathrm{fm}/c)$ due to the baryon stopping. We show that the produced field is nonperturbatively strong in the sense that the nonperturbativity parameters (e.g., the Keldysh parameter) are sufficiently large. This is in contrast to high-energy collisions $\sqrt{s_{\mathrm{NN}}}\gtrsim 100\mathrm{GeV}$, where the field is extremely short-lived and hence is perturbative. Our results imply that the electromagnetic field may have phenomenological impacts on hadronic/QCD processes in intermediate-energy heavy-ion collisions and that heavy-ion collisions can be used as a new tool to explore strong-field physics in the nonperturbative regime.

   ↳ hep-phnucl-exnucl-thPRC(2024)·13 citations
4. 04*

   Capacitive coupling study of the HERD SCD prototype: preliminary results

   Ruo-Si Lu🇨🇳 · Rui Qiao🇨🇳 · Ke Gong🇨🇳 · Wen-Xi Peng🇨🇳 · Wei-Shuai Zhang🇨🇳 · Dong-Ya Guo🇨🇳 · Jia-Ju Wei🇨🇳 · Yi-Ming Hu🇨🇳 · Jian-Hua Guo🇨🇳 · Qi Wu🇨🇳 · Peng Hu🇨🇳 · Xuan Liu🇨🇳 · Bing Lu🇨🇳 · Yi-Rong Zhang🇨🇳

   The Silicon Charge Detector (SCD) is a subdetector of the High Energy Cosmic Radiation Detection payload. The dynamic range of the silicon microstrip detector can be extended by the capacitive coupling effect, which is related to the interstrip capacitance and the coupling capacitance. A detector prototype with several sets of parameters was designed and tested in the ion beams at the CERN Super Proton Synchrotron. The capacitive coupling fractions with readout strip and floating strip incidences were studied using the beam test data and SPICE simulation.

   ↳ physics.ins-detnucl-exIEEE Trans.Nucl.Sci.(2024)·5 citations
5. 05*

   Impact of strong magnetic field, baryon chemical potential, and medium anisotropy on polarization and spin alignment of hadrons

   Bhagyarathi Sahoo🇮🇳 · Captain R. Singh🇮🇳 · Raghunath Sahoo🇮🇳

   The recent observation of global spin polarization of $\Lambda$ ($\bar{\Lambda }$) hyperons and the spin alignment of $\varphi$ and $K^{\ast 0}$ vector mesons create remarkable interest in investigating the particle polarization in the relativistic fluid produced in heavy-ion collisions at GeV/TeV energies. Among other sources of spin polarization phenomena, the Debye mass of a medium plays a crucial role in particle polarization. Any modification brought to the effective mass due to the temperature, strong magnetic field ($eB$), baryonic chemical potential (${\mu }_B$), medium anisotropy ($\xi$), and vorticity, etc., certainly affects the particle spin polarization. In this work, we explore the global hyperon spin polarization and the spin alignment of vector mesons corresponding to the strong magnetic field, baryonic chemical potential, and medium anisotropy. We find that the degree of spin polarization is flavor-dependent for hyperons. Meanwhile, vector meson spin alignment depends on the hadronization mechanisms of initially polarized quarks and anti-quarks. Medium anisotropy significantly changes the degree of spin polarization compared to the magnetic field and baryon chemical potential.

   ↳ hep-phhep-exhep-thnucl-ex+1EPJC(2025)·15 citations
6. 06*

   T-odd gluon distribution functions in a spectator model

   Alessandro Bacchetta🇮🇹 · Francesco Giovanni Celiberto🇪🇸 · Marco Radici🇮🇹

   We present a model calculation of T-odd transverse-momentum-dependent distributions of gluons in the nucleon. The model is based on the assumption that a nucleon can emit a gluon, and what remains after the emission is treated as a single spectator particle. This spectator particle is considered to be on-shell, but its mass is allowed to take a continuous range of values, described by a spectral function. The final-state interaction that is necessary to generate T-odd functions is modeled as the exchange of a single gluon between the spectator and the outgoing parton.

   ↳ hep-phhep-exnucl-exnucl-thEPJC(2024)·47 citations

* Reconstructed cohort: no mailing for this day survives in the archive. Papers are grouped by their submission times and arXiv's announcement cut-off, assuming announcement without delay; positions follow identifier order. Validated at ~91% exact-day agreement against the archived era.