Wed·Nov 4, 2015Wednesday·November 4, 2015

1. 01*

   Open $sd$-shell nuclei from first principles

   G. R. Jansen · M. D. Schuster · A. Signoracci · G. Hagen · P. Navrátil

   We extend the ab initio coupled-cluster effective interaction (CCEI) method to deformed open-shell nuclei with protons and neutrons in the valence space, and compute binding energies and excited states of isotopes of neon and magnesium. We employ a nucleon-nucleon and three-nucleon interaction from chiral effective field theory evolved to a lower cutoff via a similarity renormalization group transformation. We find good agreement with experiment for binding energies and spectra, while charge radii of neon isotopes are underestimated. For the deformed nuclei ${}^{20}$Ne and ${}^{24}$Mg we reproduce rotational bands and electric quadrupole transitions within uncertainties estimated from an effective field theory for deformed nuclei, thereby demonstrating that collective phenomena in $sd$-shell nuclei emerge from complex ab initio calculations.

   ↳ nucl-thnucl-exPRC(2016)·81 citations
2. 02*

   Jet quenching in high-energy heavy-ion collisions

   Guang-You Qin🇨🇳 · Xin-Nian Wang🇨🇳

   Jet quenching in high-energy heavy-ion collisions can be used to probe properties of hot and dense quark-gluon plasma. We provide a brief introduction to the concept and framework for the study of jet quenching. Different approaches and implementation of multiple scattering and parton energy loss are discussed. Recent progresses in the theoretical and phenomenological studies of jet quenching in heavy-ion collisions at RHIC and LHC are reviewed.

   ↳ hep-phnucl-exnucl-thIJMPE(2015)·443 citations
3. 03*

   Spectroscopy of ${}^{19}$Ne for the thermonuclear ${}^{15}$O($\alpha ,\gamma$)${}^{19}$Ne and ${}^{18}$F($p,\alpha$)${}^{15}$O reaction rates

   A. Parikh🇪🇸 · A.M. Laird🇬🇧 · N. de Séréville🇫🇷 · K. Wimmer🇺🇸 · T. Faestermann🇩🇪 · R. Hertenberger🇩🇪 · D. Seiler🇩🇪 · H.-F. Wirth🇩🇪 · P. Adsley🇬🇧 · B.R. Fulton🇬🇧 · F. Hammache🇫🇷 · J. Kiener🇫🇷 · I. Stefan🇫🇷

   Uncertainties in the thermonuclear rates of the ${}^{15}$O($\alpha ,\gamma$)${}^{19}$Ne and ${}^{18}$F($p,\alpha$)${}^{15}$O reactions affect model predictions of light curves from type I X-ray bursts and the amount of the observable radioisotope ${}^{18}$F produced in classical novae, respectively. To address these uncertainties, we have studied the nuclear structure of ${}^{19}$Ne over $E_x=4.0-5.1$ MeV and $6.1-7.3$ MeV using the ${}^{19}$F(${}^3$He,t)${}^{19}$Ne reaction. We find the $J^{\pi }$ values of the 4.14 and 4.20 MeV levels to be consistent with $9/2^{-}$ and $7/2^{-}$ respectively, in contrast to previous assumptions. We confirm the recently observed triplet of states around 6.4 MeV, and find evidence that the state at 6.29 MeV, just below the proton threshold, is either broad or a doublet. Our data also suggest that predicted but yet unobserved levels may exist near the 6.86 MeV state. Higher resolution experiments are urgently needed to further clarify the structure of ${}^{19}$Ne around the proton threshold before a reliable ${}^{18}$F($p,\alpha$)${}^{15}$O rate for nova models can be determined.

   ↳ astro-ph.SRnucl-exPRC(2015)·14 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.