Thu·Jul 21, 2022Thursday·July 21, 2022

1. 01*

   New measurement of double beta decays of ${}^{100}$Mo to excited states of ${}^{100}$Ru with the CUPID-Mo experiment

   CUPID-Mo Collaboration: C. Augier🇫🇷 · A. S. Barabash🇷🇺 · F. Bellini🇮🇹 · G. Benato🇮🇹 · M. Beretta🇺🇸 · L. Bergé🇫🇷 · J. Billard🇫🇷 · Yu. A. Borovlev🇷🇺 · L. Cardani🇮🇹 · N. Casali🇮🇹 · A. Cazes🇫🇷 · M. Chapellier🇫🇷 and 69 other authors

   The CUPID-Mo experiment, located at Laboratoire Souterrain de Modane (France), was a demonstrator experiment for CUPID. It consisted of an array of 20 Li${}_2^{100}$MoO${}_4$ (LMO) calorimeters each equipped with a Ge light detector (LD) for particle identification. In this work, we present the result of a search for two-neutrino and neutrinoless double beta decays of ${}^{100}$Mo to the first 0${}^{+}$ and $2^{+}$ excited states of ${}^{100}$Ru using the full CUPID-Mo exposure (2.71 kg$\times$yr of LMO). We measure the half-life of $2\nu \beta \beta$ decay to the $0_1^{+}$ state as $T_{1/2}^{2\nu \to 0_1^{+}}=7.5\pm 0.8\text{(stat.)}{}_{-0.3}^{+0.4}\text{(syst.)})\times 10^{20}\mathrm{yr}$. The bolometric technique enables measurement of the electron energies as well as the gamma rays from nuclear de-excitation and this allows us to set new limits on the two-neutrino decay to the $2_1^{+}$ state of T^{2\nu \rightarrow 2_1^+}_{1/2}>4.4\times 10^{21} \ \mathrm{yr} \ \text{(90 % c.i.)} and on the neutrinoless modes of T_{1/2}^{0\nu\rightarrow 2_1^+}>2.1\times10^{23} \ \mathrm{yr}\ \text{(90 % c.i.)}, T_{1/2}^{0\nu\rightarrow 0_1^+}>1.2\times10^{23} \ \mathrm{yr}\ \text{(90 % c.i.)}. Information on the electrons spectral shape is obtained which allows us to make the first comparison of the single state (SSD) and higher state (HSD) $2\nu \beta \beta$ decay models for the $0_1^{+}$ excited state of ${}^{100}$Ru.

   nucl-exPRC(2023)·25 citations
2. 02*

   Beam Energy Dependence of Fifth and Sixth-Order Net-proton Number Fluctuations in Au+Au Collisions at RHIC

   STAR Collaboration: B. E. Aboona · J. Adam · L. Adamczyk · J. R. Adams · I. Aggarwal · M. M. Aggarwal · Z. Ahammed · D. M. Anderson · E. C. Aschenauer · J. Atchison · V. Bairathi · W. Baker and 361 other authors

   We report the beam energy and collision centrality dependence of fifth and sixth order cumulants ($C_5$, $C_6$) and factorial cumulants (${\kappa }_5$, ${\kappa }_6$) of net-proton and proton distributions, from $\sqrt{s_{NN}}=3-200$ GeV Au+Au collisions at RHIC. The net-proton cumulant ratios generally follow the hierarchy expected from QCD thermodynamics, except for the case of collisions at $\sqrt{s_{NN}}$ = 3 GeV. $C_6/C_2$ for 0-40\% centrality collisions is increasingly negative with decreasing $\sqrt{s_{NN}}$, while it is positive for the lowest $\sqrt{s_{NN}}$ studied. These observed negative signs are consistent with QCD calculations (at baryon chemical potential, ${\mu }_B\le$ 110 MeV) that include a crossover quark-hadron transition. In addition, for $\sqrt{s_{NN}}\ge$ 11.5 GeV, the measured proton ${\kappa }_n$, within uncertainties, does not support the two-component shape of proton distributions that would be expected from a first-order phase transition. Taken in combination, the hyper-order proton number fluctuations suggest that the structure of QCD matter at high baryon density, ${\mu }_B\sim 750$ MeV ($\sqrt{s_{NN}}$ = 3 GeV) is starkly different from those at vanishing ${\mu }_B\sim 20$MeV ($\sqrt{s_{NN}}$ = 200 GeV and higher).

   nucl-exPRL(2023)·77 citations
3. 03*

   CME -- Experimental Results and Interpretation

   Fuqiang Wang🇺🇸

   The experimental status is reviewed on the search for the chiral magnetic effect (CME) in relativistic heavy-ion collisions. Emphasis is put on background contributions to the CME-sensitive charge correlation measurements and their effects on data interpretation.

   nucl-exhep-exnucl-thActa Phys.Polon.Supp.(2023)·7 citations
4. 04*

   Influence of heavy resonances in SMASH

   J. Salinas San Martin🇺🇸 · J. Noronha-Hostler🇺🇸 · H. Elfner🇩🇪 · J. Hammelmann🇩🇪 · R. Hirayama🇩🇪

   Recent lattice QCD results, comparing to a hadron resonance gas model, have shown the need for hundreds of particles in hadronic models. These extra particles influence both the equation of state and hadronic interactions within hadron transport models. Here, we introduce the PDG21+ particle list, which contains the most up-to-date database of particles and their properties. We then convert all particles decays into 2 body decays so that they are compatible with SMASH in order to produce a more consistent description of a heavy-ion collision.

   ↳ hep-phnucl-exnucl-thRev.Mex.Fis.Suppl.(2022)·5 citations
5. 05*

   Simultaneous Gamma-Neutron Vision device: a portable and versatile tool for nuclear inspections

   J. Lerendegui Marco · V. Babiano-Suárez🇪🇸 · J. Balibrea-Correa · L. Caballero🇪🇸 · D. Calvo · I. Ladarescu🇪🇸 · C. Domingo-Pardo🇪🇸

   GN-Vision is a novel dual $\gamma$-ray and neutron imaging system, which aims at simultaneously obtaining information about the spatial origin of $\gamma$-ray and neutron sources. The proposed device is based on two position sensitive detection planes and exploits the Compton imaging technique for the imaging of $\gamma$-rays. In addition, spatial distributions of slow- and thermal-neutron sources ($<$100 eV) are reconstructed by using a passive neutron pin-hole collimator attached to the first detection plane. The proposed gamma-neutron imaging device could be of prime interest for nuclear safety and security applications. The two main advantages of this imaging system are its high efficiency and portability, making it well suited for nuclear applications were compactness and real-time imaging is important. This work presents the working principle and conceptual design of the GN-Vision system based on Monte Carlo simulations and explores its simultaneous $\gamma$-ray and neutron detection and imaging capabilities for a realistic case of a security inspection where a ${}^{252}$Cf source is hidden in a neutron moderating container.

   ↳ physics.ins-detnucl-exphysics.app-phphysics.med-phEPJ Tech.Instrum.(2024)·4 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.