Mon·Jan 21, 2019Monday·January 21, 2019

1. 01*

   Description of the recently observed hypernucleus ${}^{15}{}_{{\Xi }^{-}}$C within a quark-meson coupling model

   R. Shyam🇮🇳 · K. Tsushima🇧🇷

   We investigate within a quark-meson coupling (QMC) model, the structure of the bound ${\Xi }^{-}$ hypernucleus ${}^{15}{}_{{\Xi }^{-}}$C (${}^{14}$N + ${\Xi }^{-}$), which has been observed in a recent analysis of the KEK-E373 experiment. In the QMC model, light quarks in nonoverlapping nucleon and ${\Xi }^{-}$ bags interact self-consistently with isoscalar-scalar ($\sigma$), isoscalar-vector ($\omega$), and isovector-vector ($\rho$) mesons in the mean field approximation. The parameters of the model (quark-meson coupling constants and masses) are mostly fixed from the nuclear matter saturation properties. The QMC model closely reproduces the separation energies of the two ${\Xi }^{-}$ hyperon states in ${}^{15}{}_{{\Xi }^{-}}$C reported in the KEK-E373 analysis, and identifies their quantum numbers. We also make predictions for the cross sections for the production of the ${}^{15}{}_{{\Xi }^{-}}$C hypernuclear specta in the ($K^{-},K^{+}$) reaction on a ${}^{15}$O target within a covariant effective Lagrangian model using the ${\Xi }^{-}$ bound state spinors obtained within the same QMC model.

   ↳ nucl-thhep-exhep-phnucl-ex11 citations
2. 02*

   A new gas-based proton-recoil telescope for quasi-absolute neutron flux measurements between 0.2 and 2 MeV neutron energy

   P. Marini🇫🇷 · L. Mathieu🇫🇷 · M. Aïche🇫🇷 · J.-L. Pedroza🇫🇷 · T. Chiron🇫🇷 · P. Baron🇫🇷 · S. Czajkowski🇫🇷 · F. Druillole🇫🇷 · P. Hellmuth🇫🇷 · B. Jurado🇫🇷 · A. Rebii🇫🇷 · I. Tsekhanovich🇫🇷

   Absolute measurements of neutron flux are an essential prerequisite of neutron-induced cross section measurements, neutron beam lines characterization and dosimetric investigations. A new gaseous detector has been developed for measurements of 0.2 to 2 MeV neutron flux based on proton-recoil process. The detector, consisting of two segmented ionization chambers read by Micromegas technology, has beed conceived to provide quasi-absolute neutron flux measurements with an accuracy of \simeq3%. The gas pressure flexibility makes the telescope non sensitive to {\gamma} and electrons background, and therefore advantageous over semi-conductor materials as a neutron flux instrument. The adjustable gas pressure and H-sample thickness, the use of Micromegas technology and the tracking capabilities allows the detection of neutrons on a large dynamical range and down to 200 keV with a good rejection of scattered neutron events and random background

   ↳ physics.ins-detnucl-ex0 citations
3. 03*

   $\Phi$ and $J/\Psi$ Mesons in Cold Nuclear Matter

   J. J. Cobos-Martínez🇲🇽 · K. Tsushima🇧🇷 · G. Krein🇧🇷 · A. W. Thomas🇦🇺

   We present $\Phi$- and $J/\Psi$--nuclear bound state energies and absorption widths for some selected nuclei, using potentials in the local density approximation computed from an effective Lagrangian approach combined with the quark-meson coupling model. Our results suggest that these mesons should form bound states with all the nuclei considered provided that these mesons are produced in nearly recoilless kinematics.

   ↳ hep-phnucl-exnucl-thJPS Conf.Proc.(2019)·3 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.