Thu·Jul 15, 2021Thursday·July 15, 2021

1. 01*

   Determination of the ${}^{209}$Bi(n,$\gamma$)${}^{210g}$Bi cross section using the NICE-Detector

   K. Al-Khasawneh · E. Borris · B. Brückner · P. Erbacher · S. Fiebiger · K. Göbel · T. Heftrich · T. Kisselbach · D. Kurtulgil · C. Langer · M. Reich · R. Reifarth and 3 other authors

   The capture cross section of ${}^{209}$Bi(n,$\gamma$)${}^{210g}$Bi was measured at different astrophysically energies including thermal capture cross section (25 meV), resonance integral, and the Maxwellian averaged cross section at a thermal energy of $kT$ = 30 keV. The partial capture cross section (${\sigma }_g$) was determined using the activation technique and by measuring the ${}^{210}$Po activity. The newly developed and tested NICE detector setup was used to measure the $\alpha$-activity of the ${}^{210}$Po. Using this setup the thermal and resonance integral cross sections were determined to be $16.2\pm 0.97$~mb and $89.81\pm 8.0$~mb, respectively. And the Maxwellian average cross section was measured to be $2.01\pm 0.38$~mb.

   nucl-exPRC(2021)·2 citations
2. 02*

   Nucleon-nucleon potentials from Delta-full chiral effective-field-theory and implications

   Y. Nosyk🇺🇸 · D. R. Entem🇪🇸 · R. Machleidt🇺🇸

   We closely investigate NN potentials based upon the Delta-full version of chiral effective field theory. We find that recently constructed NN potentials of this kind, which (when applied together with three-nucleon forces) were presented as predicting accurate binding energies and radii for a range of nuclei from A=16 to A=132 and providing accurate equations of state for nuclear matter, yield a chi^2/datum of 60 for the reproduction of the pp data below 100 MeV laboratory energy. This chi^2 is more than three times what the Hamada-Johnston potential of the year of 1962 achieved already some 60 years ago. We perceive this historical fact as concerning in view of the current emphasis on precision. We are able to trace the very large chi^2 as well as the apparent success of the potentials in nuclear structure to unrealistic predictions for P-wave states, in which the Delta-full NNLO potentials are off by up to 40 times the NNLO truncation errors. In fact, we show that, the worse the description of the P-wave states, the better the predictions in nuclear structure. Thus, these potentials cannot be seen as the solution to the outstanding problems in current miscroscopic nuclear structure physics.

   ↳ nucl-thastro-ph.SRhep-phnucl-exPRC(2021)·31 citations
3. 03*

   Kinematic dependence of azimuthal anisotropies in $p$$+$Au, $d$$+$Au, ${}^3$He+Au at $\sqrt{s_{{}_{NN}}}$ = 200 GeV

   U.A. Acharya · A. Adare · C. Aidala · N.N. Ajitanand · Y. Akiba · M. Alfred · V. Andrieux · K. Aoki · N. Apadula · H. Asano · C. Ayuso · B. Azmoun and 374 other authors

   There is strong evidence for the formation of small droplets of quark-gluon plasma in $p/d{/}^3$He+Au collisions at the Relativistic Heavy Ion Collider (RHIC) and in $p$+$p$/Pb collisions at the Large Hadron Collider. In particular, the analysis of data at RHIC for different geometries obtained by varying the projectile size and shape has proven insightful. In the present analysis, we find excellent agreement with the previously published PHENIX at RHIC results on elliptical and triangular flow with an independent analysis via the two-particle correlation method, which has quite different systematic uncertainties and an independent code base. In addition, the results are extended to other detector combinations with different kinematic (pseudorapidity) coverage. These results provide additional constraints on contributions from nonflow and longitudinal decorrelations.

   ↳ hep-exnucl-exPRC(2022)·41 citations
4. 04*

   Progress and Opportunities in Backward angle (u-channel) Physics

   C. Ayerbe Gayoso🇺🇸 · Ł. Bibrzycki🇵🇱 · S. Diehl🇩🇪 · S. Heppelmann🇺🇸 · D.W. Higinbotham🇺🇸 · G.M. Huber🇨🇦 · S.J.D. Kay🇨🇦 · S.R. Klein🇺🇸 · J.M. Laget🇺🇸 · W.B. Li🇺🇸 · V. Mathieu🇪🇸 · K. Park🇺🇸 and 8 other authors

   Backward angle (u-channel) scattering provides complementary information for studies of hadron spectroscopy and structure, but has been less comprehensively studied than the corresponding forward angle case. As a result, the physics of u-channel scattering poses a range of new experimental and theoretical opportunities and questions. We summarize recent progress in measuring and understanding high energy reactions with baryon charge exchange in the u-channel, as discussed in the first backward angle (u-channel) Physics Workshop. In particular, we discuss backward angle measurements and their theoretical description via both hadronic models and the collinear factorization approach, and discuss planned future measurements of u-channel physics. Finally, we propose outstanding questions and challenges for u-channel physics.

   ↳ hep-phnucl-exnucl-thEPJA(2021)·22 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.