Thu·Nov 15, 2018Thursday·November 15, 2018

1. 01*

   Experimental study of the $\gamma p\to K^0{\Sigma }^{+}$, $\gamma n\to K^0\Lambda$, and $\gamma n\to K^0{\Sigma }^0$ reactions at the Mainz Microtron

   C.S. Akondi🇺🇸 · K. Bantawa🇺🇸 · D.M. Manley🇺🇸 · S. Abt🇨🇭 · P. Achenbach🇩🇪 · F. Afzal🇩🇪 · P. Aguar-Bartolomé🇩🇪 · Z. Ahmed🇨🇦 · J.R.M. Annand🇬🇧 · H.J. Arends🇩🇪 · M. Bashkanov🇬🇧 · R. Beck🇩🇪 and 69 other authors

   This work measured $d\sigma /d\Omega$ for neutral kaon photoproduction reactions from threshold up to a c.m.\ energy of 1855MeV, focussing specifically on the $\gamma p\to K^0{\Sigma }^{+}$, $\gamma n\to K^0\Lambda$, and $\gamma n\to K^0{\Sigma }^0$ reactions. Our results for $\gamma n\to K^0{\Sigma }^0$ are the first-ever measurements for that reaction. These data will provide insight into the properties of $N^{\ast }$ resonances and, in particular, will lead to an improved knowledge about those states that couple only weakly to the $\pi N$ channel. Integrated cross sections were extracted by fitting the differential cross sections for each reaction as a series of Legendre polynomials and our results are compared with prior experimental results and theoretical predictions.

   nucl-exEPJA(2019)·31 citations
2. 02*

   Acoplanarity of Lepton Pair to Probe the Electromagnetic Property of Quark Matter

   Spencer Klein🇺🇸 · A.H. Mueller🇺🇸 · Bo-Wen Xiao🇨🇳 · Feng Yuan🇺🇸

   We investigate the $P_T$-broadening effects in dilepton production through photon-photon scattering in heavy ion collisions. The QED multiple interaction effects with the medium is found to be consistent with a recent observation of low transverse momentum lepton pair from ATLAS collaboration at the LHC. We further comment on the magnetic effects and point out a number of ways to disentangle these two mechanisms. In particular, the rapidity dependence of the $P_T$-broadening effects provide a unique probe to the magnetic effects.

   ↳ hep-phhep-exnucl-exnucl-thPRL(2019)·77 citations
3. 03*

   $\eta n$ photoproduction and nucleon resonances

   Jung-Min Suh🇰🇷 · Sang-Ho Kim🇰🇷 · Hyun-Chul Kim🇰🇷

   We present results of a recent work on the reaction mechanism of $\eta n$ photoproduction off the neutron in the range of $\sqrt{s}\approx 1.5-1.9$ GeV and discuss the role of various nucleon resonances listed in the Particle Data Group (PDG). We make use of an effective Lagrangian approach combining with a Regge method. The total and helicity-dependent cross sections ${\sigma }_{1/2},{\sigma }_{3/2}$ are computed and the numerical results are in good agreement with the A2 experimental data.

   ↳ hep-phhep-exnucl-exnucl-thSpringer Proc.Phys.(2020)·0 citations
4. 04*

   Ultracold Neutron Storage Simulation Using the Kassiopeia Software Package

   Z Bogorad🇺🇸 · P M Murthy🇨🇭 · J A Formaggio🇺🇸

   The Kassiopeia software package was originally developed to simulate electromagnetic fields and charged particle trajectories for neutrino mass measurement experiments. Recent additions to Kassiopeia also allow it to simulate neutral particle trajectories in magnetic fields based on their magnetic moments. Two different methods were implemented: an exact method that can work for arbitrary fields and an adiabatic method that is limited to slowly-varying fields but is much faster for large precession frequencies. Additional interactions to simulate reflection of ultracold neutrons from material walls and to allow spin-flip pulses were also added. These tools were used to simulate neutron precession in the Paul Scherrer Institute's neutron electric dipole moment experiment and predict the values of the longitudinal and transverse relaxation times as well as the trapping lifetime. All three parameters are found to closely match the experimentally determined values when simulated with both the exact and adiabatic methods, confirming that Kassiopeia is able to accurately simulate neutral particles. This opens the door for future uses of Kassiopeia to prototype the next generation of atomic traps and ultracold neutron experiments.

   ↳ physics.comp-phnucl-exphysics.ins-detNew J.Phys.(2022)·1 citation

* 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.