Wed·Feb 19, 2020Wednesday·February 19, 2020

1. 01*

   The TTIK approach for neutrons

   V. Z. Goldberg🇺🇸 · E. M. Gazeeva🇷🇺 · M. S. Golovkov · A. A. Bezbakh🇷🇺 · D. K. Nauruzbayev🇰🇿 · A. K. Nurmukhanbetova🇰🇿 · Zh. Kurmanaliyev🇷🇺 · A. Serikov🇷🇺 · B. Zalewski🇷🇺 · G.V. Rogachev🇺🇸

   We applied Thick Target Inverse Kinematics Method for a study of resonances decaying through neutron emission. As a test we used a well-studied, because of its role in s-process in stars, ${}^{13}$C($\alpha$; n) reaction. The observed energy resolution for the ${}^{13}$C($\alpha$; n) excitation function was $\sim$60 keV, the largest contributions coming from the time structure of the beam and the thickness of the neutron detector. These measurements demonstrated the high efficiency of the approach and revealed a disagreement with R-matrix calculations based on parameters of the most recent previous analysis.

   nucl-exPRResearch(2020)·1 citation
2. 02*

   Measurement of global spin alignment of $K^{\ast 0}$and $\varphi$ vector mesons using the STAR detector at RHIC

   Subhash Singha (for the STAR Collaboration)🇨🇳

   We report the transverse momentum ($p_{\mathrm{T}}$) and centrality dependence of global spin alignment (${\rho }_{00}$) of $K^{\ast 0}$ vector meson at midrapidity ($|y|<0.5$) in Au + Au collisions at $\sqrt{s_{NN}}$ = 54.4 and 200~GeV with the STAR experiment at RHIC. The $K^{\ast 0}$ results are compared to that of $\varphi$ meson. At low-$p_{\mathrm{T}}$ region and midcentral collisions, the $K^{\ast 0}$ ${\rho }_{00}$ is found to be smaller than 1/3 with about 4$\sigma$ significance, while that of $\varphi$ meson is observed to be larger than 1/3 with about 3$\sigma$ significance. The ${\rho }_{00}$ results are compared between RHIC and LHC energies. The physics implication of our results is also discussed.

   nucl-exhep-exnucl-thNPA(2021)·33 citations
3. 03*

   A covariant model for the decuplet to octet Dalitz decays

   G. Ramalho🇧🇷

   In the last years it became possible to measure in HADES the dilepton decays of several baryons. The baryon dilepton decays provide information about the electromagnetic structure of the baryons in the timelike region. In the present work, we study the $B^{\prime }\to e^{+}{e}^{-}B$ decays, where $B^{\prime }$ is a baryon decuplet member and $B$ is a baryon octet member. Our calculations are based on the covariant spectator quark model, where the contribution of the quark core is complemented with an $SU(3)$ contribution from the pion cloud. The pion cloud contribution prove to be relevant in the range of study. We present predictions for the ${\Sigma }^0(1385)\to e^{+}{e}^{-}\Lambda (1116)$ and ${\Sigma }^{+}(1385)\to e^{+}{e}^{-}{\Sigma }^{+}(1193)$ decays, which may be tested at HADES in a near future. Predictions for the remaining decuplet baryon Dalitz decays are also presented. We conclude that different orders of magnitudes are expected for the baryon decuplet Dalitz decay widths, according to the quark content of the baryons. We also conclude that the dependence of the transition form factors on the square momentum transfer ($q^2$) is important for some transitions.

   ↳ hep-phhep-exnucl-exnucl-thPRD(2020)·19 citations
4. 04*

   Vorticity and Spin Polarization --- A Theoretical Perspective

   Xu-Guang Huang🇨🇳

   We give a theoretical perspective on the vorticity and spin polarization in heavy-ion collisions. We discuss the recent progress in spin hydrodynamics and spin kinetic theory. We also discuss other effects caused by vorticity including the chiral vortical effect and rotation-induced phase transitions.

   ↳ nucl-thhep-phnucl-exNPA(2021)·51 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.