Thu·Dec 3, 2020Thursday·December 3, 2020

1. 01*

   Correlated pion-proton pair emission off hot and dense QCD matter

   J. Adamczewski-Musch (e)🇩🇪 · O. Arnold (k, j)🇩🇪 · C. Behnke (i)🇩🇪 · A. Belounnas (q)🇫🇷 · A. Belyaev (h)🇷🇺 · J.C. Berger-Chen (k, j)🇩🇪 · A. Blanco (b)🇵🇹 · C. Blume (i)🇩🇪 · M. B"ohmer (k)🇩🇪 · P. Bordalo (b)🇵🇹 · S. Chernenko (h,+)🇷🇺 · L. Chlad (r)🇨🇿 and 110 other authors

   In this letter we report the first multi-differential measurement of correlated pion-proton pairs from 2 billion Au+Au collisions at \sqrt{s_{NN}} = 2.42 GeV collected with HADES. In this energy regime the population of \Delta(1232) resonances plays an important role in the way energy is distributed between intrinsic excitation energy and kinetic energy of the hadrons in the fireball. The triple differential d3N/dM{\pi}pdpTdy distributions of correlated {\pi}p pairs have been determined by subtracting the {\pi}p combinatorial background using an iterative method. The invariant-mass distributions in the \Delta(1232) mass region show strong deviations from a Breit-Wigner function with vacuum width and mass. The yield of correlated pion-proton pairs exhibits a complex isospin, rapidity and transverse-momentum dependence. In the invariant mass range 1.1 < Minv (GeV/c2) < 1.4, the yield is found to be similar for {\pi}+p and {\pi}-p pairs, and to follow a power law <Apart>^{\alpha}, where <Apart> is the mean number of participating nucleons. The exponent {\alpha} depends strongly on the pair transverse momentum (pT) while its pT-integrated and charge-averaged value is {\alpha} = 1.5 \pm 0.08stat \pm 0.2sys.

   nucl-exPLB(2021)·9 citations
2. 02*

   Study of the magnetic octupole moment of ${}^{173}$Yb using collinear laser spectroscopy

   R. P. de Groote · S. Kujanpää🇫🇮 · Á. Koszorús🇧🇪 · J.G. Li🇨🇳 · I. D. Moore🇫🇮

   The hyperfine constants of the ${}^3$P${}_2^{\circ }$ state in neutral Yb have been measured using three different dipole transitions. This state was recently shown to have a comparatively large hyperfine magnetic octupole splitting, and thus a puzzlingly large magnetic octupole moment. The measurement is performed using collinear laser spectroscopy on a fast atomic beam, which provides a straightforward route to probing long-lived metastable atomic states with high resolution. From the combined analysis of all three lines we find no significant evidence for a non-zero octupole moment in ${}^{173}$Yb.

   ↳ physics.atom-phnucl-exPRA(2021)·20 citations
3. 03*

   Folding-model approach to reaction cross section of ${}^{4,6,8}$He+${}^{12}$C scattering at 790 MeV (published in Results in Physics)

   Shingo Tagami🇯🇵 · Tomotsugu Wakasa🇯🇵 · Maya Takechi🇩🇪 · Jun Matsui · Masanobu Yahiro🇯🇵

   Tanihata {\it et al.} determined matter radii $r_m({\sigma }_{\mathrm{I}})$ for ${}^{4,6,8}$He from interaction cross sections ${\sigma }_{\mathrm{I}}$ of ${}^{4,6,8}$He+${}^{12}$C scattering at 790 MeV per nucleon, using the optical limit of the Glauber model. Lu {\it et al.} determined proton radii $r_p(\mathrm{AIS})$ for ${}^{4,6,8}$He with the atomic isotope shifts (AIS). We investigate whether the Love-Franey $t$-matrix folding model is good for ${}^{4,6,8}$He+${}^{12}$C scattering at 790 MeV per nucleon.

   ↳ nucl-thnucl-ex2 citations
4. 04*

   Bottomonium suppression in an open quantum system using the quantum trajectories method

   Nora Brambilla🇩🇪 · Miguel Ángel Escobedo🇪🇸 · Michael Strickland🇺🇸 · Antonio Vairo🇩🇪 · Peter Vander Griend🇩🇪 · Johannes Heinrich Weber🇩🇪

   We solve the Lindblad equation describing the Brownian motion of a Coulombic heavy quark-antiquark pair in a strongly coupled quark-gluon plasma using the highly efficient Monte Carlo wave-function method. The Lindblad equation has been derived in the framework of pNRQCD and fully accounts for the quantum and non-Abelian nature of the system. The hydrodynamics of the plasma is realistically implemented through a 3+1D dissipative hydrodynamics code. We compute the bottomonium nuclear modification factor and compare with the most recent LHC data. The computation does not rely on any free parameter, as it depends on two transport coefficients that have been evaluated independently in lattice QCD. Our final results, which include late-time feed down of excited states, agree well with the available data from LHC 5.02 TeV PbPb collisions.

   ↳ hep-phnucl-exnucl-thphysics.comp-phJHEP(2021)·101 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.