Thu·May 10, 2018Thursday·May 10, 2018

1. 01*

   Nuclear surface diffuseness revealed in nucleon-nucleus diffraction

   S. Hatakeyama · W. Horiuchi🇯🇵 · A. Kohama

   Nuclear surface provides useful information on nuclear radius, nuclear structure as well as properties of nuclear matter. We discuss the relationship between the nuclear surface diffuseness and elastic scattering differential cross section at the first diffraction peak of high-energy nucleon-nucleus scattering as an efficient tool in order to extract the nuclear surface information from limited experimental data involving short-lived unstable nuclei. The high-energy reaction is described by a reliable microscopic reaction theory, the Glauber model. Extending the idea of the black sphere model, we find one-to-one correspondence between the nuclear bulk structure information and proton elastic scattering diffraction peak. This implies that we can extract both the nuclear radius and diffuseness simultaneously, using the position of the first diffraction peak and its magnitude of the elastic scattering differential cross section. We confirm the reliability of this approach by using realistic density distributions obtained by a mean-field model.

   ↳ nucl-thnucl-exPRC(2018)·32 citations
2. 02*

   Kinetic freeze-out properties from transverse momentum spectra of pions in high energy proton-proton collisions

   Li-Li Li🇨🇳 · Fu-Hu Liu🇨🇳

   Transverse momentum spectra of negative and positive pions produced at mid-(pseudo)rapidity in inelastic or non-single-diffractive proton-proton collisions over a center-of-mass energy, $\sqrt{s}$, range from a few GeV to above 10 TeV are analyzed by the blast-wave fit with Boltzmann (Tsallis) distribution. The blast-wave fit results are well fitting to the experimental data measured by several collaborations. In a particular superposition with Hagedorn function, both the excitation functions of kinetic freeze-out temperature ($T_0$) of emission source and transverse flow velocity (${\beta }_T$) of produced particles obtained from a given selection in the blast-wave fit with Boltzmann distribution have a hill at $\sqrt{s}\approx 10$ GeV, a drop at dozens of GeV, and then an increase from dozens of GeV to above 10 TeV. However, both the excitation functions of $T_0$ and ${\beta }_T$ obtained in the blast-wave fit with Tsallis distribution do not show such a complex structure, but a very low hill. In another selection for the parameters or in the superposition with the usual step function, $T_0$ and ${\beta }_T$ increase generally quickly from a few GeV to about 10 GeV and then slightly at above 10 GeV, there is no such the complex structure, when also studying nucleus-nucleus collisions.

   ↳ hep-phhep-exnucl-exnucl-thMDPI Physics(2020)·17 citations
3. 03*

   Behavior of the collective rotor in wobbling motion

   E. Streck · Q. B. Chen🇩🇪 · N. Kaiser🇩🇪 · Ulf-G. Meißner🇩🇪

   The behavior of the collective rotor in wobbling motion is investigated within the particle-rotor model for the nucleus ${}^{135}$Pr by transforming the wave functions from the $K$-representation to the $R$-representation. After reproducing the experimental energy spectra and wobbling frequencies, the evolution of the wobbling mode in ${}^{135}$Pr, from transverse at low spins to longitudinal at high spins, is illustrated by the distributions of the total angular momentum in the intrinsic reference frame (azimuthal plot). Finally, the coupling schemes of the angular momenta of the rotor and the high-$j$ particle for transverse and longitudinal wobbling are obtained from the analysis of the probability distributions of the rotor angular momentum ($R$-plots) and their projections onto the three principal axes ($K_R$-plots).

   ↳ nucl-thnucl-exPRC(2018)·54 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.