Fri·Aug 28, 2020Friday·August 28, 2020

1. 01*

   Determination of luminosity for in-ring reactions: A new approach for the low-energy domain

   Y.M. Xing · J. Glorius · L. Varga · L. Bott · C. Brandau B. Bruckner · R.J. Chen · X. Chen · S. Dababneh · T. Davinson · P. Erbacher · S. Fiebiger · T. Gassner and 50 other authors

   Luminosity is a measure of the colliding frequency between beam and target and it is a crucial parameter for the measurement of absolute values, such as reaction cross sections. In this paper, we make use of experimental data from the ESR storage ring to demonstrate that the luminosity can be precisely determined by modelling the measured Rutherford scattering distribution. The obtained results are in good agreement with an independent measurement based on the x-ray normalization method. Our new method provides an alternative way to precisely measure the luminosity in low-energy stored-beam configurations. This can be of great value in particular in dedicated low-energy storage rings where established methods are difficult or impossible to apply.

   nucl-exNucl.Instrum.Meth.A(2020)·5 citations
2. 02*

   A comprehensive analysis of differential cross sections and analyzing powers in the proton-deuteron break-up channel at 135 MeV

   H. Tavakoli-Zaniani🇳🇱 · M. Eslami-Kalantari🇮🇷 · H. R. Amir-Ahmadi🇳🇱 · M. T. Bayat · A. Deltuva🇱🇹 · J. Golak🇵🇱 · N. Kalantar-Nayestanaki🇳🇱 · St. Kistryn🇵🇱 · A. Kozela🇵🇱 · H. Mardanpour🇳🇱 · J. G. Messchendorp🇳🇱 · M. Mohammadi-Dadkan🇳🇱 and 5 other authors

   A selection of measured cross sections and vector analyzing powers, Ax and Ay, are presented for the pd break-up reaction. The data are taken with a polarized proton beam energy of 135 MeV using the Big Instrument for Nuclear-polarization Analysis (BINA) at KVI, the Netherlands. With this setup, Ax is extracted for the first time for a large range of energies as well as polar and azimuthal angles of the two outgoing protons. For most of the configurations, the results at small and large relative azimuthal angles differ in behavior when comparing experimental data with the theoretical calculations. We also performed a more global comparison of our data with theoretical calculations using a chi-square (${\chi }^2$) analysis. The cross-section results show huge values of ${\chi }^2$/d.o.f.. The absolute values of ${\chi }^2$/d.o.f. for the components of vector analyzing powers, Ax and Ay, are smaller than the ones for the cross section, partly due to larger uncertainties for these observables. However, also for these observables no satisfactory agreement is found for all angular combinations. This implies that the present models of a three-nucleon force are not able to provide a satisfactory description of experimental data.

   nucl-exEPJA(2021)·3 citations
3. 03*

   Learning about the QCD medium using electromagnetic and weak probes

   Gojko Vujanovic🇺🇸

   Recent theoretical developments concerning radiation of electromagnetic and weak probes in ultra-relativistic heavy-ion collisions is overviewed. These proceedings focus on electromagnetic probes and briefly cover weak probes. An outlook regarding the future use of electromagnetic probes is formulated whereby a quantitative Bayesian comparison, simultaneously employing electromagnetic and hadronic calculations of experimental observables against data, is highlighted as a path towards a better understanding of the properties of the QCD medium.

   ↳ nucl-thhep-phnucl-exPoS(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.