Tue·Sep 1, 2020Tuesday·September 1, 2020

1. 01*

   Robustness of chiral symmetry in atomic nuclei with reflection-asymmetric shapes

   C. M. Petrache🇫🇷

   The present paper is a comment regarding the robustness of the chirality in presence of the space-reflection asymmetry, which leads to pairs of interleaved positive- and negative-parity bands. The recent results reported in Ref. \cite{2006.12062} which introduced the $chiture$ and $chiplex$ quantum numbers to describe an ideal nuclear system with simultaneous chiral and reflection symmetry breaking, are commented.

   ↳ nucl-thnucl-exSci.Bull.(2020)·1 citation
2. 02*

   Enhancement of low-mass dileptons in ultraperipheral collisions

   I.M. Dremin🇷🇺 · S.R. Gevorkyan🇷🇺 · D.T. Madigozhin🇷🇺

   It is shown that production of low-mass $e^{+}{e}^{-}$-pairs in ultraperipheral nuclear collisions is enhanced due to the Sommerfeld-Gamow-Sakharov (SGS) factor. This effect is especially strong near the threshold of creation of unbound $e^{+}{e}^{-}$-pairs with low masses in the two-photon fusion. Coulomb attraction of the non-relativistic components of such pairs may lead to the increased intensity of 511 keV photons. It can be recorded at the NICA collider and has some astrophysical implications. The analogous effect can be observed at LHC in dilepton production.

   ↳ hep-phastro-ph.HEhep-exnucl-ex+1EPJC(2021)·8 citations
3. 03*

   Advances in modeling nuclear matrix elements of neutrinoless double beta decay

   J. M. Yao🇺🇸

   Accurate nuclear matrix elements (NMEs) for neutrinoless double beta decays of candidate nuclei are important for the design and interpretation of future experiments. Significant progress has been made in the modeling of these NMEs from first principles. The NME for 48Ca shows a good agreement among three different ab initio calculations starting from the same nuclear interaction constructed within the chiral EFT and the same decay operator. These studies open the door to ab initio calculations of the matrix elements for the decay of heavier nuclei such as 76Ge, 130Te, and 136Xe. The ultimate goal is the computation of NMEs in many-body calculations with controllable approximations, using nuclear interactions and weak transition operators derived consistently from chiral EFT. We are expecting more progress towards this goal in the near future.

   ↳ nucl-thhep-exhep-phnucl-exSci.Bull.(2021)·6 citations
4. 04*

   Heavy Quark Radiation in the Quark-Gluon Plasma in the Moliere Theory: Angular Distribution of the Radiation

   B. Blok (Technion)🇮🇱

   We study the effects of adding the Coulomb interactions to the harmonic oscillator (HO) approximation of the heavy parton propagating through the quark-gluon plasma (the extension to QCD of the Molliere theory). We explicitly find the expression for the transverse momentum distribution of the gluon radiation of the heavy quark propagating in the quark gluon plasma in the framework of the Moliere theory, taking into account the BDMPSZ radiation in the harmonic oscillator (HO) approximation, and the Coulomb logarithms described by the additional logarithmic terms in the effective potential. We show that these Coulomb logarithms significantly influence the HO distribution, derived in the BDMPSZ works, especially for the small transverse momenta, filling the dead cone, and reducing the dead cone suppression of the heavy quark radiation (dead cone effect). In addition we study the effect of the phase space constraints on the heavy quark energy loss, and argue that taking into account of both the phase space constraints and of the Coulomb gluons reduces the dependence of the heavy quark energy loss on its mas in the HO approximation.

   ↳ hep-phhep-exnucl-exnucl-thEPJC(2021)·8 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.