Mon·Jan 16, 2017Monday·January 16, 2017

1. 01*

   ${}^{137,138,139}$La($n$, $\gamma$) cross sections constrained with statistical decay properties of ${}^{138,139,140}$La nuclei

   Bonginkosi Vincent Kheswa🇳🇴 · Mathis Wiedeking · Josh Brown🇺🇸 · Ann-Cecilie Larsen🇳🇴 · Stephane Goriely🇧🇪 · Magne Guttormsen🇳🇴 · Frank L Bello Garrote🇳🇴 · Lee A Bernstein🇺🇸 · Darren L. Bleuel🇺🇸 · Tomas K Eriksen🇳🇴 · Francesca Giacoppo🇳🇴 · Andreas Görgen🇳🇴 and 13 other authors

   The nuclear level densities and $\gamma$-ray strength functions of ${}^{138,139,140}$La were measured using the ${}^{139}$La(${}^3$He, $\alpha$), ${}^{139}$La(${}^3$He, ${}^3$He${}^{\prime }$) and ${}^{139}$La(d, p) reactions. The particle-$\gamma$ coincidences were recorded with the silicon particle telescope (SiRi) and NaI(Tl) (CACTUS) arrays. In the context of these experimental results, the low-energy enhancement in the A$\sim$140 region is discussed. The ${}^{137,138,139}$La($n,\gamma )$ cross sections were calculated at $s$- and $p$-process temperatures using the experimentally measured nuclear level densities and $\gamma$-ray strength functions. Good agreement is found between ${}^{139}$La($n,\gamma )$ calculated cross sections and previous measurements.

   nucl-exPRC(2017)·22 citations
2. 02*

   Nuclear Symmetry Energy Extracted from Laboratory Experiments

   Bao-An Li🇺🇸

   Some recent progress and open questions in extracting and understanding the new physics underlying the density dependence of nuclear symmetry energy from laboratory experiments are discussed.

   ↳ nucl-thnucl-exNucl.Phys.News(2017)·76 citations
3. 03*

   Nucleon resonances $N(1875)$ and $N(2100)$ as strange partners of LHCb pentaquarks

   Jun He🇨🇳

   In this work, we investigate the possibility of interpreting two nucleon resonances, the $N(1875)$ and the $N(2100)$, as hadronic molecular states from the ${\Sigma }^{\ast }K$ and $\Sigma K^{\ast }$ interactions, respectively. With the help of effective Lagrangians in which coupling constants are determined by the SU(3) symmetry, the ${\Sigma }^{\ast }K$ and $\Sigma K^{\ast }$ interactions are described by the vector-meson and pseudoscalar-meson exchanges. With the one-boson-exchange potential obtained, bound states from the ${\Sigma }^{\ast }K$ and $\Sigma K^{\ast }$ interactions are searched for in a quasipotential Bethe-Saltpeter equation approach. A bound state with quantum number $I(J^P)=1/2(3/2^{-})$ is produced from the ${\Sigma }^{\ast }K$ interaction, which can be identified as the $N(1875)$ listed in PDG. It can be seen as a strange partner of the LHCb pentaquark $P_c(4380)$ with the same quantum numbers in the molecular state picture. The $\Sigma K^{\ast }$ interaction also produces a bound state with quantum number $I(J^P)=1/2(3/2^{-})$, which is related to experimentally observed $N(2100)$ in the $\varphi$ photoproduction. Our results suggest that the $N(2120)$ observed in the $K\Lambda (1520)$ photoproduction and the $N(2100)$ observed in the $\varphi$ photoproduction have different origins. The former is a conventional three-quark state while the latter is a $\Sigma K^{\ast }$ molecular state, which can be seen as a strange partner of the $P_c(4450)$ with different spin parity.

   ↳ hep-phhep-exnucl-exnucl-thPRD(2017)·69 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.