Tue·Nov 13, 2018Tuesday·November 13, 2018

1. 01*

   Isomeric fission yield ratios for odd-mass Cd and In isotopes using the Phase-Imaging Ion-Cyclotron-Resonance technique

   V. Rakopoulos · M. Lantz🇸🇪 · S. Pomp · A. Solders · A. Al-Adili · L. Canete · T. Eronen🇫🇮 · A. Jokinen🇫🇮 · A. Kankainen🇫🇮 · A. Mattera · I. D. Moore🇫🇮 · D. A. Nesterenko🇫🇮 and 6 other authors

   Isomeric yield ratios for the odd-$A$ isotopes of ${}^{119-127}$Cd and ${}^{119-127}$In from 25-MeV proton-induced fission on natural uranium have been measured at the JYFLTRAP double Penning trap, by employing the Phase-Imaging Ion-Cyclotron-Resonance technique. With the significantly improved mass resolution of this novel method isomeric states separated by 140 keV from the ground state, and with half-lives of the order of 500 ms, could be resolved. This opens the door for obtaining new information on low-lying isomers, of importance for nuclear structure, fission and astrophysics. In the present work the experimental isomeric yield ratios are used for the estimation of the root-mean-square angular momentum ($J_{\mathrm{rms}}$) of the primary fragments. The results show a dependency on the number of unpaired protons and neutrons, where the odd-$Z$ In isotopes carry larger angular momenta. The deduced values of $J_{\mathrm{rms}}$ display a linear relationship when compared with the electric quadrupole moments of the fission products.

   nucl-exPRC(2019)·24 citations
2. 02*

   Laboratory Probes of the Neutron-Matter Equation of State

   M.B. Tsang🇺🇸 · C.Y. Tsang🇺🇸 · P. Danielewicz🇺🇸 · W.G. Lynch🇺🇸 · F.J. Fattoyev🇺🇸

   To relate constraints from nuclear physics to the tidal deformabilities of neutron stars, we construct a neutron star model that accepts input from a large collection of Skyrme density functions to calculate properties of 1.4 solar-mass neutron stars. We find that restricting this set of Skyrme to density functions that describe nuclear masses, isobaric analog states, and low energy nuclear reactions does not sufficiently restrict the predicted neutron-star radii and the tidal deformabilities. However, pressure constraints on the EoS around twice saturation density ($2\times 2.74\times 10^{14}g/c{m}^3$), obtained from high energy nucleus-nucleus collisions, does constrain predicted tidal deformabilities with uncertainties smaller than those obtained from the analysis of GW170817. We also found that the density-pressure constraint on the EoS obtained from a recent analysis of the neutron-star merger event agree very well with the density pressure constraints obtained from nuclear physics experiments published in 2002.

   nucl-exnucl-th4 citations
3. 03*

   Event Shape Engineering and Multiplicity dependent Study of Identified Particle Production in proton+proton Collisions at $\sqrt{s}$= 13 TeV using PYTHIA8

   Arvind Khuntia🇮🇳 · Sushanta Tripathy🇮🇳 · Ashish Bisht🇮🇳 · Raghunath Sahoo🇮🇳

   Small system collectivity observed at the LHC energies along with enhancement of strangeness makes high-multiplicity proton+proton (pp) collisions very interesting in order to look for QGP-like features, usually found in heavy-ion collisions. It may be interesting to perform a double differential study of different observables in pp collisions in terms of charged particle multiplicity and event shape in order to understand the new dimensions in high-multiplicity pp physics. We study the correlation between the number of multi-partonic interactions (nMPI), event shape (transverse spherocity) and charged particle multiplicity classes. For the first time, we report the simulation results on the spherocity and charged particle multiplicity dependent study of (${\pi }^{+}+{\pi }^{-}$), (K${}^{+}$+K${}^{-}$), (p+$\bar{\mathrm{p}}$), K${}^{\ast 0}$, $\varphi$ and ($\Lambda +\bar{\Lambda }$) production in pp collisions at $\sqrt{s}$ = 13 TeV using PYTHIA8. We explore the event shape and charged particle multiplicity dependence of the transverse momentum ($p_{\mathrm{T}}$) spectra, integrated yield, mean transverse momentum ($⟨p_{\mathrm{T}}⟩$) and particle ratios of the identified particles. This study provides a baseline for exploring the the event topology and final state multiplicity dependence of identified particle production in the LHC pp collisions.

   ↳ hep-phhep-exnucl-exnucl-thJ.Phys.G(2021)·31 citations
4. 04*

   Mapping the QCD phase diagram with statistics friendly distributions

   Adam Bzdak🇵🇱 · Volker Koch🇺🇸

   We demonstrate that the multiplicity distribution of a system located in the vicinity of a first-order phase transition can be successfully measured in terms of its factorial cumulants with a surprisingly small number of events. This finding has direct implications for the experimental search of a QCD phase transition conjectured to be located in the high baryon density region of the QCD phase diagram.

   ↳ nucl-thhep-exhep-phnucl-exPRC(2019)·31 citations
5. 05*

   Description of bulk observables in Au+Au collisions at top RHIC energy in the integrated HydroKinetic Model

   M. D. Adzhymambetov🇺🇦 · V. M. Shapoval🇺🇦 · Yu. M. Sinyukov🇺🇦

   The results on the main bulk observables obtained in the simulations within the integrated hydrokinetic model (iHKM) of Au+Au collisions at the RHIC energy $\sqrt{s_{NN}}=200$ GeV are presented along with the corresponding experimental data from the STAR and the PHENIX collaborations. The simulations include all the stages of the collision process: formation of the initial state, its gradual thermalization and hydrodynamization, viscous relativistic hydro-evolution, system's hadronization and particlization, and, finally, an expansion of the interacting hadron-resonance gas. The model gives a satisfactory description of charged-particle multiplicities, particle number ratios, transverse momentum spectra for pions, kaons, protons and antiprotons, charged-particle $v_2$ coefficients, and femtoscopy radii at all collision centralities. It is demonstrated how one can estimate the times of the pion and kaon maximal emission from the femto-scales.

   ↳ hep-phnucl-exnucl-thNPA(2019)·10 citations
6. 06*

   Test of the Standard Model in Neutron Beta Decay with Polarized Electron and Unpolarized Neutron and Proton

   A. N. Ivanov🇦🇹 · R. Höllwieser🇦🇹 · N. I. Troitskaya🇦🇹 · M. Wellenzohn🇦🇹 · Ya. A. Berdnikov🇷🇺

   We calculate the correlation coefficients of the electron-energy and electron-antineutrino angular distribution of the neutron beta decay with polarized electron and unpolarised neutron and proton. The calculation is carried out within the Standard Model (SM) with the contributions, caused by the weak magnetism, proton recoil and radiative corrections of order of 10^{-3}, Wilkinson's corrections of order 10^{-5}$(Wilkinson, Nucl. Phys. A377, 474 (1982) and Ivanov et al., Phys. Rev. C95, 055502 (2017)) and the contributions of interactions beyond the SM. The obtained results can be used for the analysis of experimental data on searches of interactions beyond the SM at the level of 10^{-4} (Abele, Hyperfine Interact. 237, 155 (2016)). The contributions of G-odd correlations are calculated and found at the level of 10^{-5} in agreement with the results obtained by Gardner and Plaster (Phys. Rev. C87, 065504 (2013)) and Ivanov et al. (Phys. Rev. C98, 035503 (2018)).

   ↳ hep-phgr-qcnucl-exPRD(2019)·15 citations
7. 07*

   Fissile material detection using neutron time-correlations from photofission

   R. A. Soltz🇺🇸 · A. Danagoulian · E. P. Hartouni · M. S. Johnson · S. A. Sheets · A. Glenn🇺🇸 · S. E. Korbly · R. J. Ledoux

   The detection of special nuclear materials (SNM) in commercial cargoes is a major objective in the field of nuclear security. In this work we investigate the use of two-neutron time-correlations from photo-fission using the Prompt Neutrons from Photofission (PNPF) detectors in Passport Systems Inc.'s (PSI) Shielded Nuclear Alarm Resolution (SNAR) platform~\cite{pnpf} for the purpose of detecting $\sim$5~kg quantities of fissionable materials in seconds. The goal of this effort was to extend the secondary scan mode of this system to differentiate fissile materials, such as highly enriched uranium, from fissionable materials, such as low enriched and depleted uranium (LEU and DU). Experiments were performed using a variety of material samples, and data were analyzed using the variance-over-mean technique referred to as $Y_{2F}$ or Feynman-$\alpha$. Results were compared to computational models to improve our ability to predict system performance for distinguishing fissile materials. Simulations were then combined with empirical formulas to generate receiver operating characteristics (ROC) curves for a variety of shielding scenarios. We show that a 10 second screening with a 200~$\mu$A 9~MeV X-ray beam is sufficient to differentiate kilogram quantities of HEU from DU in various shielding scenarios in a standard cargo container.

   ↳ physics.ins-detnucl-exphysics.app-phAIP Adv.(2019)·1 citation

* 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.