Tue·Jul 24, 2018Tuesday·July 24, 2018

1. 01*

   Open heavy-flavour production and elliptic flow in p-Pb collisions at the LHC with ALICE

   Henrique J. C. Zanoli (on behalf of the ALICE Collaboration)🇳🇱

   Measurements of open heavy flavour production in p--A collisions allow the investigation of Cold Nuclear Matter effects. In addition, they are an important tool for a complementary investigation of the long-range correlations found in small systems in the light flavour sector. In this work, production measurements of D mesons at mid-rapidity in p--Pb collisions at $\sqrt{s_{\mathrm{NN}}}$ = 5.02 TeV are reported. Production yields are also reported for the heavy-flavour hadron decay electrons at central rapidity at $\sqrt{s_{\mathrm{NN}}}$ = 5.02 and 8.16 TeV. The elliptic flow ($v_2$) of heavy-flavour hadron decay electrons in high-multiplicity p-Pb collisions at $\sqrt{s_{\mathrm{NN}}}$ = 5.02 TeV is found to be positive with a significance larger than $5\sigma$.

   nucl-exNPA(2019)·1 citation
2. 02*

   Investigation of antineutrino spectral anomaly with updated nuclear database

   Xubo Ma🇨🇳 · Le Yang🇨🇳 · Liang Zhan🇨🇳 · Fengpeng An🇨🇳 · Jun Cao🇨🇳

   Recently, three successful antineutrino experiments (Daya Bay, Double Chooz, and RENO) measured the neutrino mixing angle theta_13; however, significant discrepancies were found, both in the absolute flux and spectral shape. In this study, the antineutrino spectra were calculated by using the updated nuclear database, and we found that the four isotopes antineutrino spectrum have all contribution to the 5--7 MeV bump with ENDF/B-VII.1 fission yield. The bump can be explained well using the updated library and more important isotopes contribution to the bump were also given. In the last, the fission yield correlation coefficient between the four isotopes were discussed, and found that the correlation coefficients are very large.

   nucl-exhep-ex4 citations
3. 03*

   A large area detector for thermal neutron flux measurements at the KamLAND site

   Alexandre Kozlov🇯🇵 · Dmitry Chernyak🇯🇵

   A large area (0.5~m $\times$ 0.5~m) thermal neutron detector was developed based on 0.32~mm-thick ${}^6$LiF:ZnS(Ag) scintillator sheets. The detector was constructed for measurements of seasonal variations in low intensity thermal neutron flux at deep underground sites. The detector response to neutrons was studied using a low intensity ${}^{241}$Am/${}^9$Be($\alpha$,n) neutron source. The digital pulse shape discrimination technique was applied to separate neutron capture events from the background caused by traces of $\alpha$-emitters from Uranium and Thorium decay chains in scintillator components. The thermal neutron detection efficiency was 0.368$\pm$0.018 (0.155$\pm$0.009) before (after) event selection based on the digital pulse shape discrimination method. The measured $\alpha$-particle background event rate in the ${}^6$LiF:ZnS(Ag) scintillator was (4.88$\pm$0.06(stat))$\times$10${}^{-6}$ $\alpha$ cm${}^{-2}$sec${}^{-1}$. As a test of detector performance we measured the thermal neutron flux at the KamLAND area of the Kamioka neutrino observatory and compared it with result of the neutron flux measurement carried out at the Super-Kamiokande site. The thermal neutron flux at KamLAND was (6.43$\pm$0.50)$\times$10${}^{-6}$ n cm${}^{-2}$sec${}^{-1}$ that included $\sim$10~\% contribution from neutrons with energies above 1~eV. During the detector construction we identified a source of high amplitude noise pulses generated by 5-inch R1250 photomultipliers manufactured by Hamamatsu Photonics K. K..

   ↳ physics.ins-detnucl-exNucl.Instrum.Meth.A(2018)·6 citations
4. 04*

   Matrix Models of Strength Distributions

   Larry Zamick🇺🇸 · Arun Kingan

   In this work we use matrix models to study the problem of strength distributions. This is motivated by noticing near exponential fall offs of strengths in calculated magnetic dipole excitations. We emphasize that the quality of the exponential fall offs depend on the parameters in our matrices, especially the relative size of the couplings to the unperturbed level separations. We also find a matrix for which all transitions vanish.

   ↳ nucl-thnucl-exphysics.atom-phIJMPE(2018)·5 citations
5. 05*

   Short-range correlations and the charge density

   Ronen Weiss🇮🇱 · Axel Schmidt🇺🇸 · Gerald A. Miller🇺🇸 · Nir Barnea🇮🇱

   Sophisticated high-energy and large momentum-transfer scattering experiments combined with ab-initio calculations can reveal the short-distance behavior of nucleon pairs in nuclei. On an opposite energy and resolution scale, elastic electron scattering experiments are used to extract the charge density and charge radius of different nuclei. We show that even though the charge density has no obvious connection with nuclear short-range correlations, it can be used to extract properties of such correlations. This is accomplished by using the nuclear contact formalism to derive a relation between the charge density and the proton-proton nuclear contacts that describe the probability of two protons being at close proximity. With this relation, the values of the proton-proton contacts are extracted for various nuclei using only the nuclear charge density and a solution of the two-nucleon Schroedinger equation as inputs. For symmetric nuclei, the proton-neutron contacts can also be extracted from the charge density. Good agreement is obtained with previous extractions of the nuclear contacts. These results imply that one can predict (with reasonably good accuracy) the results of high-energy and large momentum-transfer electron-scattering experiments and ab-initio calculations of high momentum tails using only experimental data of elastic scattering experiments.

   ↳ nucl-thcond-mat.quant-gasnucl-exPLB(2019)·21 citations
6. 06*

   Hadronic resonances, strange and multi-strange particle production in Xe-Xe and Pb-Pb collisions with ALICE at the LHC

   D. S. D. Albuquerque (for the ALICE Collaboration)🇧🇷

   We present measurements of hadronic resonance, strange and multi-strange particle production in collisions of Xe-Xe and Pb-Pb at the center-of-mass energies of $\sqrt{s_{NN}}=5.44$ and $5.02$ TeV, respectively, by the ALICE collaboration at the LHC. Particle ratios are presented as a function of multiplicity for $K_s^0$, $\Lambda$, ${\Xi }^{-}$, ${\bar{\Xi }}^{+}$, ${\Omega }^{-}$, ${\bar{\Omega }}^{+}$, $\rho (770{)}^0$, $K^{\ast }(892{)}^0$, $\varphi (1020)$ and $\Lambda (1520)$. Our results are discussed and compared with predictions of QCD-inspired event generators. Additionally, comparisons with lower energy measurements and smaller systems are also presented.

   ↳ hep-exnucl-exNPA(2019)·25 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.