Thu·Oct 19, 2023Thursday·October 19, 2023

1. 01*

   Study of charm hadronization and in-medium modification at the Electron-ion Collider in China

   Senjie Zhu🇨🇳 · Xiao Huang🇨🇳 · Lei Xia🇨🇳 · Aiqiang Guo🇨🇳 · Yutie Liang🇨🇳 · Yifei Zhang🇨🇳 · Yuxiang Zhao🇨🇳

   Charm quark production and its hadronization in ep and eA collisions at the future Electron-Ion Collider in China (EicC) will help us understand the quark/gluon fragmentation processes and the hadronization mechanisms in the nuclear medium, especially within a poorly constrained kinematic region ($x<0.1$). In this paper, we report a study on the production of charmed hadrons, $D^0$ and ${\Lambda }_c^{+}$, reconstructed with a dedicated GEANT4 simulation of vertex$\&$tracking detectors designed for EicC. The ${\Lambda }_c^{+}$/$D^0$ ratios as functions of multiplicity and $p_T$, as well as the $D^0$ double ratio are presented with projected statistical precision.

   nucl-exPRD(2024)·1 citation
2. 02*

   Measurement of $\omega$ meson production in pp and p-Pb collisions at $\sqrt{s_{\text{NN}}}=5.02$TeV with ALICE

   Nicolas Strangmann🇩🇪

   The ALICE experiment at the LHC investigates the properties of the hot and dense nuclear matter created in heavy-ion collisions. By comparing the particle production in pp and p-Pb collisions, possible nuclear initial state effects can be isolated. Measurements of the $\omega$ meson $p_{\text{T}}$-spectra in pp and p-Pb collisions not only allow for a determination of the nuclear modification factor $R_{\text{pPb}}$, but also provide insight into the fragmentation process and serve as vital input for decay background simulations for direct photons. In this contribution, measurements of the $\omega$ meson production in pp and p-Pb collisions at $\sqrt{s_{\text{NN}}}=5.02$TeV are presented. This includes the signal extraction and various corrections of the $\omega$ meson yields, leading to their production cross sections and the first measured nuclear modification factor $R_{\text{pPb}}$ of the $\omega$ meson at LHC energies.

   nucl-exhep-exPoS(2024)·1 citation
3. 03*

   Shape polarization in the tin isotopes near $N=60$ from precision $g$-factor measurements on short-lived $11/2^{-}$ isomers

   T. J. Gray🇺🇸 · A. E. Stuchbery🇦🇺 · J. Dobaczewski🇬🇧 · A. Blazhev🇩🇪 · H. A. Alshammari🇦🇺 · L. J. Bignell🇦🇺 · J. Bonnard🇬🇧 · B. J. Coombes🇦🇺 · J. T. H. Dowie🇦🇺 · M. S. M. Gerathy🇦🇺 · T. Kibédi🇦🇺 · G. J. Lane🇦🇺 and 7 other authors

   The $g$ factors of $11/2^{-}$ isomers in semimagic ${}^{109}$Sn and ${}^{111}$Sn (isomeric lifetimes $\tau =2.9(3)$ ns and $\tau =14.4(7)$ ns, respectively) were measured by an extension of the Time Differential Perturbed Angular Distribution technique, which uses \LaBr detectors and the hyperfine fields of a gadolinium host to achieve precise measurements in a new regime of short-lived isomers. The results, $g(11/2^{-};{}^{109}\text{Sn})=-0.186(8)$ and $g(11/2^{-};{}^{111}\text{Sn})=-0.214(4)$, are significantly lower in magnitude than those of the $11/2^{-}$ isomers in the heavier isotopes and depart from the value expected for a near pure neutron $h_{11/2}$ configuration. Broken-symmetry density functional theory calculations applied to the sequence of $11/2^{-}$ states reproduce the magnitude and location of this deviation. The $g(11/2^{-})$ values are affected by shape core polarization; the odd $0h_{11/2}$ neutron couples to $J^{\pi }=2^{+},4^{+},6^{+}...$ configurations in the weakly-deformed effective core, causing a decrease in the $g$-factor magnitudes.

   nucl-exnucl-thPLB(2023)·4 citations
4. 04*

   The mechanical radius of the proton

   V.D. Burkert🇺🇸 · L. Elouadrhiri🇺🇸 · F.X. Girod🇺🇸

   We present the first determination of the proton mechanical radius. The result was obtained by employing a novel theoretical approach that connects experimental data of deeply virtual Compton scattering with the spin = 2 interaction that is characteristic of gravity coupling with matter. We find that the proton mechanical radius is significantly smaller than its charge radius, consistent with the latest Lattice QCD computation.

   ↳ hep-phhep-latnucl-exnucl-th20 citations
5. 05*

   Determination of the Equation of State from Nuclear Experiments and Neutron Star Observations

   Chun Yuen Tsang🇺🇸 · ManYee Betty Tsang🇺🇸 · William G. Lynch🇺🇸 · Rohit Kumar🇺🇸 · Charles J. Horowitz🇺🇸

   With recent advances in neutron star observations, major progress has been made in determining the pressure of neutron star matter at high density. This pressure is constrained by the neutron star deformability, determined from gravitational waves emitted in a neutron-star merger, and measurements of radii of two neutron stars, using a new X-ray observatory on the International Space Station. Previous studies have relied on nuclear theory calculations to provide the equation of state at low density. Here we use a combination of 15 constraints composed of three astronomical observations and twelve nuclear experimental constraints that extend over a wide range of densities. Bayesian Inference is then used to obtain a comprehensive nuclear equation of state. This data-centric result provides benchmarks for theoretical calculations and modeling of nuclear matter and neutron stars. Furthermore, it provides insights on the composition of neutron stars and their cooling via neutrino radiation.

   ↳ nucl-thastro-ph.HEnucl-exNature Astron.(2024)·109 citations
6. 06*

   Causal hydrodynamic fluctuations in a one-dimensional expanding system

   Shin-ei Fujii🇯🇵 · Tetsufumi Hirano🇯🇵

   We derive equations of motion of hydrodynamic fluctuations performing perturbative expansion of the energy-momentum conservation equations around the boost invariant solution in one-dimensional expanding system. In the course of derivation, we do not assume any specific forms of constitutive equations for shear stress tensor ${\pi }^{\mu \nu }$ and bulk pressure $\Pi$. Therefore, the framework enables us to employ any constitutive equations beyond the Navier-Stokes theory which satisfy the causality. Employing Israel-Stewart equations as examples of the constitutive equations, we demonstrate the dynamics of causal hydrodynamic fluctuations in (1+1)-dimensional Milne coordinates. We observe that structure of energy density fluctuations is almost frozen in the early stage of the expansion. Two-point correlations of energy density fluctuations turn out to be closely related with the properties of the medium such as sound velocity, viscosity, and relaxation time. Furthermore, we show that two-particle correlation functions of final hadrons after freezeout inherit correlations of thermodynamic variables and flow rapidity. This opens a new door for an analysis of transport properties of the medium produced in relativistic heavy ion collisions.

   ↳ nucl-thhep-phnucl-exPRC(2024)·3 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.