Tue·Mar 19, 2019Tuesday·March 19, 2019

1. 01*

   Recent Results from the CERN LHC Experiment TOTEM -- Implications for Odderon Exchange

   T. Csörgő (for the TOTEM Collaboration)🇭🇺

   Recent results are summarized from the TOTEM experiment at CERN LHC, including measurements of the total, elastic and inelastic cross-sections, the nuclear slope parameter $B$, the differential cross-section of elastic scattering and the real to imaginary part ration $\rho$ at $\sqrt{s}=$ 2.76 and 13 TeV. The implications of these data for Odderon (odd-gluon colorless) exchange are discussed.

   ↳ hep-exhep-phnucl-exEPJ Web Conf.(2019)·12 citations
2. 02*

   Combined Neyman-Pearson Chi-square: An Improved Approximation to the Poisson-likelihood Chi-square

   Xiangpan Ji🇺🇸 · Wenqiang Gu🇺🇸 · Xin Qian🇺🇸 · Hanyu Wei🇺🇸 · Chao Zhang🇺🇸

   We describe an approximation to the widely-used Poisson-likelihood chi-square using a linear combination of Neyman's and Pearson's chi-squares, namely "combined Neyman-Pearson chi-square" (${\chi }_{\mathrm{CNP}}^2$). Through analytical derivations and toy model simulations, we show that ${\chi }_{\mathrm{CNP}}^2$ leads to a significantly smaller bias on the best-fit model parameters compared to those using either Neyman's or Pearson's chi-square. When the computational cost of using the Poisson-likelihood chi-square is high, ${\chi }_{\mathrm{CNP}}^2$ provides a good alternative given its natural connection to the covariance matrix formalism.

   ↳ physics.data-anhep-exnucl-exNucl.Instrum.Meth.A(2020)·71 citations
3. 03*

   Toroidal states in ${}^{28}$Si with covariant density functional theory in 3D lattice space

   Z. X. Ren🇨🇳 · P. W. Zhao🇨🇳 · S. Q. Zhang🇨🇳 · J. Meng🇨🇳

   The toroidal states in ${}^{28}$Si with spin extending to extremely high are investigated with the cranking covariant density functional theory on a 3D lattice. Thirteen toroidal states with spin $I$ ranging from 0 to 56$\hslash$ are obtained, and their stabilities against particle emissions are studied by analyzing the density distributions and potentials. The excitation energies of the toroidal states at $I=28$, 36, 44$\hslash$ reasonably reproduce the observed three resonances extracted from the 7-$\alpha$ de-excitation of ${}^{28}$Si. The $\alpha$ clustering of these toroidal states is supported by the $\alpha$-localization function.

   ↳ nucl-thnucl-exNPA(2020)·32 citations
4. 04*

   Nuclear dependence of the transverse single-spin asymmetry in the production of charged hadrons at forward rapidity in polarized $p+p$, $p+$Al, and $p+$Au collisions at $\sqrt{s_{{}_{NN}}}=200$ GeV

   C. Aidala · Y. Akiba · M. Alfred · V. Andrieux · N. Apadula · H. Asano · B. Azmoun · V. Babintsev · N.S. Bandara · K.N. Barish · S. Bathe · A. Bazilevsky and 292 other authors

   We report on the nuclear dependence of transverse single-spin asymmetries (TSSAs) in the production of positively-charged hadrons in polarized $p^{\uparrow }+p$, $p^{\uparrow }+$Al and $p^{\uparrow }+$Au collisions at $\sqrt{s_{{}_{NN}}}=200$ GeV. The measurements have been performed at forward rapidity ($1.4<\eta <2.4$) over the range of $1.8<p_T<7.0$ GeV$/c$ and $0.1<x_F<0.2$. We observed a positive asymmetry $A_N$ for positively-charged hadrons in \polpp collisions, and a significantly reduced asymmetry in $p^{\uparrow }$+$A$ collisions. These results reveal a nuclear dependence of charged hadron $A_N$ in a regime where perturbative techniques are relevant. These results provide new opportunities to use \polpA collisions as a tool to investigate the rich phenomena behind TSSAs in hadronic collisions and to use TSSA as a new handle in studying small-system collisions.

   ↳ hep-exnucl-exPRL(2019)·23 citations
5. 05*

   Neutron lifetime splitting in beta-decay

   V.V. Vasiliev

   The author considers a hypothesis of neutron lifetime splitting in beta-decay and shows that the beta-decay of neutrons could be described by the triad of lifetimes tau_{Left}, tau_{Mean}, tau_{Right}. The lifetime tau_{Left} is the lifetime of L-neutrons emitting electrons against the neutron spin direction (L-type neutron decay). The lifetime tau_{Right} is the lifetime of R-neutrons emitting electrons in the direction of the neutron spin (R-type neutron decay). The lifetime tau_{Mean} is the arithmetic average of tau_{Left}, tau_{Right} or the mean neutron lifetime. While using the parameters of electron-spin asymmetry of neutron decay and the results for determining the mean neutron lifetime, the performed numerical estimates gave the numerical values of the triad tau_{Left}, tau_{Mean}, tau_{Right} as 813 s, 900 s and 987 s respectively. In addition to the estimates, the lifetimes of the triad are determined from experimental data applying the decay scale tuning method proposed by the author. The experimental values of the triad coincided with the estimates with high accuracy. The weighted average neutron lifetime tau_{W} determined from the experimental neutron lifetimes tau_{Left} and tau_{Right} is equal to tau_{W}=833.33 +- 0.02 s, and is in good agreement with the values of the neutron lifetime obtained by the other methods.

   ↳ physics.data-annucl-ex1 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.