Mon·Sep 25, 2023Monday·September 25, 2023

1. 01*

   Reaction plane correlated triangular flow in Au+Au collisions at $\sqrt{s_{NN}}=3$ GeV

   STAR Collaboration: M. I. Abdulhamid🇪🇬 · B. E. Aboona🇺🇸 · J. Adam🇨🇿 · L. Adamczyk🇵🇱 · J. R. Adams🇺🇸 · I. Aggarwal · M. M. Aggarwal · Z. Ahammed🇮🇳 · E. C. Aschenauer🇺🇸 · S. Aslam🇮🇳 · J. Atchison🇺🇸 · V. Bairathi🇨🇱 and 353 other authors

   We measure triangular flow relative to the reaction plane at 3 GeV center-of-mass energy in Au+Au collisions at the BNL Relativistic Heavy Ion Collider. A significant $v_3$ signal for protons is observed, which increases for higher rapidity, higher transverse momentum, and more peripheral collisions. The triangular flow is essentially rapidity-odd with a slope at mid-rapidity, $d{v}_3/dy{|}_{(y=0)}$, opposite in sign compared to the slope for directed flow. No significant $v_3$ signal is observed for charged pions and kaons. Comparisons with models suggest that a mean field potential is required to describe these results, and that the triangular shape of the participant nucleons is the result of stopping and nuclear geometry.

   nucl-exPRC(2024)·11 citations
2. 02*

   The dynamic hadronization of charm quarks in heavy-ion collisions

   Christian Bierlich🇸🇪 · Gösta Gustafson🇸🇪 · Leif Lönnblad🇸🇪 · Harsh Shah🇸🇪

   The PYTHIA8/ANGANTYR model for heavy ion collisions was recently updated with a mechanism for \textit{global colour reconnection}. The colour reconnection model used is QCD colour algebra inspired and enhances baryon production due to the formation of string junctions. In this paper, we present updates to the junction formation and string fragmentation mechanisms, connected to heavy quark fragmentation. This allows for the simulation of heavy quark fragmentation, using junction formation, in heavy ion collisions. The framework is validated for proton collisions, and we show results for charm baryon production in proton-lead collisions.

   ↳ hep-phhep-exnucl-exEPJC(2024)·17 citations
3. 03*

   Constraints for the X17 boson from compacts objects observations

   A. Kanakis-Pegios🇬🇷 · V. Petousis🇨🇿 · M. Veselsky🇨🇿 · Jozef Leja🇸🇰 · Ch.C. Moustakidis🇬🇷

   We investigate the hypothetical X17 boson on neutron stars and Quark Stars (QSs) using various hadronic Equation of States (EoSs) with phenomenological or microscopic origin. Our aim is to set realistic constraints on its coupling constant and the mass scaling, with respect to causality and various possible upper mass limits and the dimensionless tidal deformability ${\Lambda }_{1.4}$. In particular, we pay special attention on two main phenomenological parameters of the X17, the one is related to the coupling constant $\mathrm{g}$ that it has with hadrons or quarks and the other with the in-medium effects through the regulator $\mathrm{C}$. Both are very crucial concerning the contribution on the total energy density and pressure. In the case of considering the X17 as a carrier of nuclear force in Relativistic Mean Field (RMF) theory, an admixture into vector boson segment was constrained by 20\% and 30\%. In our investigation, we came to the general conclusion that the effect of the hypothetical X17 both on neutron and QSs constrained mainly by the causality limit, which is a specific property of each EoS. Moreover, it depends on the interplay between the main two parameters that is the interaction coupling $\mathrm{g}$ and the in-medium effects regulator $\mathrm{C}$. These effects are more pronounced in the case of QSs concerning all the bulk properties.

   ↳ nucl-thastro-ph.HEnucl-exPRD(2024)·13 citations
4. 04*

   Revealing the Origin of Mass through Studies of Hadron Spectra and Structure

   Craig D. Roberts🇨🇳

   The Higgs boson is responsible for roughly 1% of the visible mass in the Universe. Obviously, therefore, Nature has another, very effective way of generating mass. In working toward identifying the mechanism, contemporary strong interaction theory has arrived at a body of basic predictions, viz. the emergence of a nonzero gluon mass-scale, a process-independent effective charge, and dressed-quarks with constituent-like masses. These three phenomena - the pillars of emergent hadron mass (EHM) - explain the origin of the vast bulk of visible mass in the Universe. Their expressions in hadron observables are manifold. This contribution highlights a few; namely, some of the roles of EHM in building the meson spectrum, producing the leading-twist pion distribution amplitude, and moulding hadron charge and mass distributions.

   ↳ hep-phhep-exhep-latnucl-ex+1EPJ Web Conf.(2024)·0 citations
5. 05*

   A comparison of the neutron detection efficiency and response characteristics of two pixelated PSD-capable organic scintillator detectors with different photo-detection readout methods

   J. Balajthy🇺🇸 · P. Marleau · M. Sweany

   We characterize the performance of two pixelated neutron detectors: a PMT-based array that utilizes Anger logic for pixel identification and a SiPM-based array that employs individual pixel readout. The SiPM-based array offers improved performance over the previously developed PMT-based detector both in terms of uniformity and neutron detection efficiency. Each detector array uses PSD-capable plastic scintillator as a detection medium. We describe the calibration and neutron efficiency measurement of both detectors using a ${}^{137}$Cs source for energy calibration and a ${}^{252}$Cf source for calibration of the neutron response. We find that the intrinsic neutron detection efficiency of the SiPM-based array is ($30.2\pm 1.7$)\%, which is almost twice that of the PMT-based array, which we measure to be ($16.9\pm 0.2$)\%.

   ↳ physics.ins-detnucl-exJINST(2024)·1 citation

* 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.