Thu·Aug 20, 2020Thursday·August 20, 2020

1. 01*

   Strange Hadron Spectroscopy with Secondary KL Beam in Hall D

   KLF Collaboration: Moskov Amaryan (ODU)🇺🇸 · Mikhail Bashkanov (UoY)🇬🇧 · Sean Dobbs (FSU)🇺🇸 · James Ritman (Ruhr-U.)🇩🇪 · Justin Stevens (W&M)🇺🇸 · Igor Strakovsky (GWU)🇺🇸 · Shankar Adhikari (ODU)🇺🇸 · Arshak Asaturyan (YerPhi)🇺🇸 · Alexander Austregesilo (JLab)🇺🇸 · Marouen Baalouch (C.E.A.)🇺🇸 · Vitaly Baturin (ODU)🇺🇸 · Vladimir Berdnikov (CUA)🇺🇸 and 140 other authors

   We propose to create a secondary beam of neutral kaons in Hall D at Jefferson Lab to be used with the GlueX experimental setup for strange hadron spectroscopy. The superior CEBAF electron beam will enable a flux on the order of $1\times 10^4{K}_L/sec$, which exceeds the flux of that previously attained at SLAC by three orders of magnitude. The use of a deuteron target will provide first measurements ever with neutral kaons on neutrons. The experiment will measure both differential cross sections and self-analyzed polarizations of the produced $\Lambda$, $\Sigma$, $\Xi$, and $\Omega$ hyperons using the GlueX detector at the Jefferson Lab Hall D. The measurements will span CM $\cos \theta$ from $-0.95$ to 0.95 in the range W = 1490 MeV to 2500 MeV. The new data will significantly constrain the partial wave analyses and reduce model-dependent uncertainties in the extraction of the properties and pole positions of the strange hyperon resonances, and establish the orbitally excited multiplets in the spectra of the $\Xi$ and $\Omega$ hyperons. Comparison with the corresponding multiplets in the spectra of the charm and bottom hyperons will provide insight into he accuracy of QCD-based calculations over a large range of masses. The proposed facility will have a defining impact in the strange meson sector through measurements of the final state $K\pi$ system up to 2 GeV invariant mass. This will allow the determination of pole positions and widths of all relevant $K^{\ast }(K\pi )$ $S$-,$P$-,$D$-,$F$-, and $G$-wave resonances, settle the question of the existence or nonexistence of scalar meson $\kappa /K_0^{\ast }(700)$ and improve the constrains on their pole parameters. Subsequently improving our knowledge of the low-lying scalar nonet in general.

   nucl-exhep-exhep-phnucl-th72 citations
2. 02*

   The Structure of ${}^{33}$Si and the magicity of the N=20 gap at Z=14

   S. Jongile🇿🇦 · A. Lemasson🇫🇷 · O. Sorlin🇫🇷 · M. Wiedeking🇿🇦 · P. Papka🇿🇦 · D. Bazin🇺🇸 · C. Borcea🇷🇴 · R. Borcea🇷🇴 · A. Gade🇺🇸 · H. Iwasaki🇺🇸 · E. Khan🇫🇷 · A. Lepailleur🇫🇷 and 11 other authors

   The structure of ${}^{33}$Si was studied by a one-neutron knockout reaction from a ${}^{34}$Si beam at 98.5 MeV/u incident on a ${}^9$Be target. The prompt $\gamma$-rays following the de-excitation of ${}^{33}$Si were detected using the GRETINA $\gamma$-ray tracking array while the reaction residues were identified on an event-by-event basis in the focal plane of the S800 spectrometer at NSCL (National Superconducting Cyclotron Laboratory). The presently derived spectroscopic factor values, $C^{2}S$, for the 3/2${}^{+}$ and 1/2${}^{+}$ states, corresponding to a neutron removal from the $0d_{3/2}$ and $1s_{1/2}$ orbitals, agree with shell model calculations and point to a strong $N=20$ shell closure. Three states arising from the more bound $0d_{5/2}$ orbital are proposed, one of which is unbound by about 930 keV. The sensitivity of this experiment has also confirmed a weak population of 9/2${}^{-}$ and 11/2${}_{1,2}^{-}$ final states, which originate from a higher-order process. This mechanism may also have populated, to some fraction, the 3/2${}^{-}$ and 7/2${}^{-}$ negative-parity states, which hinders a determination of the $C^{2}S$ values for knockout from the normally unoccupied $1p_{3/2}$ and $0f_{7/2}$ orbits.

   nucl-exPRC(2020)·9 citations
3. 03*

   Neutron capture cross sections of radioactive nuclei

   C.A. Bertulani🇺🇸 · B.V. Carlson🇧🇷

   Alternative methods to calculate neutron capture cross sections on radioactive nuclei are reported using the theory of Inclusive Non-Elastic Breakup (INEB) developed by Hussein and McVoy [1]. The statistical coupled-channels theory proposed in Ref. [2] is further extended in the realm of random matrices. The case of reactions with the projectile and the target being two-cluster nuclei is also analyzed and applications are made for scattering from a deuteron target [3]. An extension of the theory to a three-cluster projectile incident on a two-cluster target is also discussed. The theoretical developments described here should open new possibilities to obtain information on the neutron capture cross sections of radioactive nuclei using indirect methods.

   ↳ nucl-thnucl-exBraz.J.Phys.(2021)·0 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.