Tue·Dec 6, 2022Tuesday·December 6, 2022

1. 01*

   Measurements of azimuthal anisotropy of nonprompt D${}^0$ mesons in PbPb collisions at $\sqrt{s_{\mathrm{NN}}}$ = 5.02 TeV

   CMS Collaboration

   Measurements of the elliptic ($v_2$) and triangular ($v_3$) azimuthal anisotropy coefficients are presented for D${}^0$ mesons produced in b hadron decays (nonprompt D${}^0$ mesons) in lead-lead collisions at $\sqrt{s_{\mathrm{NN}}}$ = 5.02 TeV. The results are compared with previously published charm meson anisotropies measured using prompt D${}^0$ mesons. The data were collected with the CMS detector in 2018 with an integrated luminosity of 0.58 nb${}^{-1}$. Azimuthal anisotropy is sensitive to the interactions of quarks with the hot and dense medium created in heavy ion collisions. Comparing results for prompt and nonprompt D${}^0$ mesons can assist in understanding the mass dependence of these interactions. The nonprompt results show lower magnitudes of $v_2$ and $v_3$ and weaker dependences on the meson transverse momentum and collision centrality than those found for prompt D${}^0$ mesons. The results are in agreement with theoretical predictions that include a mass dependence in the interactions of quarks with the medium.

   nucl-exhep-exPLB(2024)·29 citations
2. 02*

   Measurement of the ${}^{159}$Tb(n, $\gamma$) cross section at the CSNS Back-n facility

   S. Zhang · G. Li · W. Jiang · D.X. Wang · J. Ren · E.T. Li · M. Huang · J.Y.Tang · X.C. Ruan · H.W. Wang · Z.H. Li · Y.S. Chen and 10 other authors

   The stellar (n, $\gamma$) cross section data for the mass numbers around A $\approx$ 160 are of key importance to nucleosynthesis in the main component of the slow neutron capture process, which occur in the thermally pulsing asymptotic giant branch (TP--AGB). The new measurement of (n, $\gamma$) cross sections for ${}^{159}$Tb was performed using the C${}_6$D${}_6$ detector system at the back streaming white neutron beam line (Back-n) of the China spallation neutron source (CSNS) with neutron energies ranging from 1 eV to 1 MeV. Experimental resonance capture kernels were reported up to 1.2 keV neutron energy with this capture measurement. Maxwellian-averaged cross sections (MACS) were derived from the measured ${}^{159}$Tb (n, $\gamma$) cross sections at $kT$ = 5 $\sim$ 100 keV and are in good agreement with the recommended data of KADoNiS-v0.3 and JEFF-3.3, while KADoNiS-v1.0 and ENDF-VIII.0 significantly overestimate the present MACS up to 40$\%$ and 20$\%$, respectively. A sensitive test of the s-process nucleosynthesis was also performed with the stellar evolution code MESA. Significant changes in abundances around A $\approx$ 160 were observed between the ENDF/B-VIII.0 and present measured rate of ${}^{159}$Tb(n, $\gamma$)${}^{160}$Tb in the MESA simulation.

   nucl-exastro-ph.SRPRC(2023)·5 citations
3. 03*

   In-situ measurement of the velocity spectrum of ultracold neutrons and its evolution using an oscillating detector

   D. Rozpedzik🇵🇱 · K. Bodek🇵🇱 · K. Kirch🇨🇭 · B. Lauss🇨🇭 · K. Lojek🇵🇱 · I. Rienaecker · P. Schmidt-Wellenburg🇨🇭 · G. Zsigmond🇨🇭

   Ultracold neutrons (UCNs) are used in experiments investigating fundamental interactions, testing the Standard Model of particle physics and searching for phenomena beyond it. Knowledge of the energy spectrum of UCNs is very often a key ingredient to determine the systematic effects in precision measurements utilizing UCNs. The proposed novel method allows for the in-situ measurements of the UCN velocity distribution and its time evolution. In addition, the proposed UCN spectrometer can be a handy diagnostic tool for monitoring the spectrum in critical places in the UCN transport system connecting an UCN source with experiments. In this paper, we show the results from the measurements performed at the Paul Scherrer Institute's UCN source.

   nucl-exphysics.ins-det0 citations
4. 04*

   Charge-dependent anisotropic flow in high-energy heavy-ion collisions from relativistic resistive magneto-hydrodynamic expansion

   Kouki Nakamura🇯🇵 · Takahiro Miyoshi🇯🇵 · Chiho Nonaka🇯🇵 · Hiroyuki R. Takahashi🇯🇵

   We have investigated the charge-dependent anisotropic flow in high-energy heavy-ion collisions, using relativistic resistive magneto-hydrodynamics (RRMHD). We consider the optical Glauber model as an initial model of the quark-gluon plasma (QGP) and the solution of the Maxwell equations with source term of the charged particles in two colliding nuclei as initial electromagnetic fields. The RRMHD simulation is performed with these initial conditions in Au-Au and Cu-Au collisions at $\sqrt{s_{\mathrm{NN}}}=200$ GeV. We have calculated the charge-odd contribution to the directed flow $\Delta v_1$ and elliptic flow $\Delta v_2$ in both collisions based on electric charge distributions as a consequence of RRMHD. Our results show that the $\Delta v_1$ and $\Delta v_2$ are approximately proportional to the electrical conductivity ($\sigma$) of the medium. In the $\sigma =0.023{\mathrm{fm}}^{-1}$ case, our result of $\Delta v_1$ is consistent with STAR data in Au-Au collisions. Furthermore, in Cu-Au collisions, $\Delta v_1$ has a non-zero value at $\eta =0$. We conclude that the charge-dependent anisotropic flow is a good probe to extract the electrical conductivity of the QGP medium in high-energy heavy-ion experiments.

   ↳ nucl-thhep-phnucl-exPRC(2023)·17 citations
5. 05*

   Progress in Nuclear Astrophysics: a multi-disciplinary field with still many open questions

   S. Goriely🇧🇪 · A. Choplin🇧🇪 · W. Ryssens🇧🇪 · I. Kullmann🇧🇪

   Nuclear astrophysics is a multi-disciplinary field with a huge demand for nuclear data. Among its various fields, stellar evolution and nucleosynthesis are clearly the most closely related to nuclear physics. The need for nuclear data for astrophysics applications challenges experimental techniques as well as the robustness and predictive power of present nuclear models. Despite impressive progress for the last years, major problems and puzzles remain. In the present contribution, only a few nuclear astrophysics specific aspects are discussed. These concern some experimental progress related to the measurement of key reactions of relevance for the so-called s-and p-processes of nucleosynthesis, the theoretical effort in predicting nuclear properties of exotic neutron-rich nuclei of interest for the r-process nucleosynthesis, and the recent introduction of machine learning techniques in nuclear astrophysics applications.

   ↳ nucl-thastro-ph.HEastro-ph.SRnucl-exJ.Phys.Conf.Ser.(2023)·1 citation
6. 06*

   Neutrino-tagged jets at the Electron-Ion Collider

   Miguel Arratia🇺🇸 · Zhong-Bo Kang🇺🇸 · Sebouh J. Paul🇺🇸 · Alexei Prokudin🇺🇸 · Felix Ringer🇺🇸 · Fanyi Zhao🇺🇸

   We explore the potential of jet observables in charged-current deep-inelastic scattering (CC DIS) events at the future Electron-Ion Collider (EIC). Tagging jets with a recoiling neutrino, which can be identified by the event's missing transverse momentum, will allow for flavor-sensitive measurements of Transverse Momentum Dependent parton distribution functions (TMDs). We present the first predictions for transverse-spin asymmetries in azimuthal neutrino-jet correlations and hadron-in-jet measurements. We study the kinematic reach and the precision of these measurements and explore their feasibility using parameterized detector simulations. We conclude that jet production in CC DIS, while challenging in terms of luminosity requirements, will complement the EIC experimental program to study the three-dimensional structure of the nucleon encoded in TMDs.

   ↳ hep-phhep-exnucl-exnucl-thPRD(2023)·17 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.