Tue·Jul 23, 2019Tuesday·July 23, 2019

1. 01*

   Direct real photons in relativistic heavy ion collisions

   Gabor David🇺🇸

   Direct real photons are arguably the most versatile tools to study relativistic heavy ion collisions. They are produced, by various mechanisms, during the entire space-time history of the strongly interacting system. Also, being colorless, most the time they escape without further interaction, ie they are penetrating probes. This makes them rich in information, but hard to decypher and interpret. This review presents the experimental and theoretical developments related to direct real photons since the 1970s, with a special emphasis on the recently emerged "direct photon puzzle", the simultaneous presence of large yields and strong azimuthal asymmetries of photons in heavy ion collisions, an observation that so far eluded full and coherent explanation.

   nucl-exhep-exnucl-thRept.Prog.Phys.(2020)·118 citations
2. 02*

   Probing quark transversity GPDs in diffractive photo- and electroproduction on the deuteron

   W. Cosyn🇧🇪 · B. Pire🇫🇷 · L. Szymanowski🇵🇱

   Transversity generalized parton distributions (GPDs) can be probed in diffractive electro- and photoproduction of two vector mesons on a hadron in kinematics where the two vector mesons are separated by a large rapidity gap. We report on calculations for this process in the case of coherent ${\rho }^0-\omega$ meson production on a deuteron target. Our cross section results show that an electron-ion collider with deuteron beams and forward detectors could probe deuteron transversity GPDs.

   ↳ hep-phnucl-exnucl-thPoS(2019)·5 citations
3. 03*

   Far-Field Monitoring of Reactor Antineutrinos for Nonproliferation

   Viacheslav A. Li🇺🇸

   Numerous experimental efforts have shown that antineutrino-based monitoring provides a non-intrusive means to estimate the fissile content and relative thermal power of nuclear reactors for nonproliferation. Until now, there have been no experimental demonstrations dedicated to exploring the nonproliferation potential of large detectors required for long-range monitoring. The goal of the Advanced Instrumentation Testbed (AIT) program is to test novel methods for the discovery of reactor cores, specifically in the mid-field to far-field, beyond 200 meters and out to tens or hundreds of kilometers, using kiloton-scale to megaton-scale detectors. The main physical infrastructure of the AIT consists of an underground laboratory in the Boulby mine in Northern England. The site is located at a 26-km standoff from the Hartlepool Reactor Complex, which houses two 1.5-GWth advanced gas-cooled reactors. The first detector to be deployed at the AIT is the WATer CHerenkov Monitor of ANtineutrinos (WATCHMAN). WATCHMAN will use ~6,000 tons of gadolinium-doped water in order to detect a few reactor antineutrinos per week from the Hartlepool reactor complex. WATCHMAN will focus on understanding the signal efficiency, radiological backgrounds, and the reactor operational status. Here, the nonproliferation goals are to understand the sensitivity for discovery of one reactor in the presence of another, the discovery of any reactor operations above a well-understood background, and the sensitivity to confirm the declared operational cycles of both reactors. Uniquely, AIT-WATCHMAN also offers a flexible platform at which nascent technologies such as water-based scintillator and fast photomultiplier tubes can be tested in real-world conditions. We present the AIT-WATCHMAN program and status.

   ↳ physics.ins-dethep-exnucl-ex3 citations
4. 04*

   Polarisabilities of the nucleon in baryon chiral perturbation theory and beyond

   Vadim Lensky🇩🇪 · Vladimir Pascalutsa🇩🇪

   We review the recent baryon chiral perturbation theory results for the nucleon polarisabilities that describe the different regimes of nucleon Compton scattering --- real, virtual, and doubly virtual. We stress the importance of the empirical verification of the theory in the context of the calculation of the inelastic nucleon structure corrections, such as the two-photon exchange contributions. We also discuss the recently obtained constraints that relate the different regimes of nucleon Compton scattering and can provide additional information on the nucleon structure.

   ↳ hep-phnucl-exnucl-thPoS(2019)·1 citation
5. 05*

   Impact of Uncertainties in Nuclear Reaction Cross Sections on p-Nucleosynthesis in Thermonuclear Supernovae

   T. Rauscher🇨🇭 · N. Nishimura🇯🇵 · G. Cescutti🇮🇹 · R. Hirschi🇬🇧 · A. St.J. Murphy🇬🇧 · C. Travaglio

   The propagation of uncertainties in reaction cross sections and rates of neutron-, proton-, and alpha-induced reactions into the final isotopic abundances obtained in nucleosynthesis models is an important issue in studies of nucleosynthesis and Galactic Chemical Evolution. We developed a Monte Carlo method to allow large-scale postprocessing studies of the impact of nuclear uncertainties on nucleosynthesis. Temperature-dependent rate uncertainties combining realistic experimental and theoretical uncertainties are used. From detailed statistical analyses uncertainties in the final abundances are derived as probability density distributions. Furthermore, based on rate and abundance correlations an automated procedure identifies the most important reactions in complex flow patterns from superposition of many zones or tracers. The method so far was already applied to a number of nucleosynthesis processes. Here we focus on the production of p-nuclei in white dwarfs exploding as thermonuclear (type Ia) supernovae. We find generally small uncertainties in the final abundances despite of the dominance of theoretical nuclear uncertainties. A separate analysis of low- and high-density regions indicates that the total uncertainties are dominated by the high-density regions.

   ↳ astro-ph.HEnucl-exnucl-thJPS Conf.Proc.(2020)·1 citation
6. 06*

   Prompt, pre-equilibrium, and thermal photons in relativistic nuclear collisions

   Akihiko Monnai🇯🇵

   The direct photon emission model in relativistic nuclear colliders has been improved in recent years for reducing the discrepancy between theoretical estimations and experimental data and for understanding the properties of the QCD matter. In this study, the contribution of pre-equilibrium photons are investigated in addition to those of prompt and thermal photons in the framework of a relativistic hydrodynamic model. The numerical simulations at an LHC energy suggest that the pre-equilibrium photons may be relevant at intermediate transverse momentum near the saturation momentum scale, increasing particle spectra and reducing elliptic flow of direct photons.

   ↳ nucl-thhep-phnucl-exJ.Phys.G(2020)·29 citations
7. 07*

   CUPID pre-CDR

   The CUPID Interest Group

   CUPID is a proposed future tonne-scale bolometric neutrinoless double beta decay ($0\nu \beta \beta$) experiment to probe the Majorana nature of neutrinos and discover Lepton Number Violation in the so-called inverted hierarchy region of the neutrino mass. CUPID will be built on experience, expertise and lessons learned in CUORE, and will exploit the current CUORE infrastructure as much as possible. In order to achieve its ambitious science goals, CUPID aims to dramatically reduce the backgrounds in the region of interest introducing a high efficiently $\alpha$/$\beta$ discrimination techniques, also demonstrated by the CUPID-0 and CUPID-Mo experiments, and using a high transition energy double beta decay nucleus, ${}^{100}$Mo. This document describe the main concepts related with the design of the CUPID experiment and indicates the projected sensitivities and the global scientific goal of the experiment.

   ↳ physics.ins-dethep-exnucl-ex188 citations
8. 08*

   Double Polarization Observables in Pentaquark Photoproduction

   JPAC Collaboration: Daniel Winney🇺🇸 · Cristiano Fanelli🇺🇸 · Alessandro Pilloni🇮🇹 · Astrid N. Hiller Blin🇩🇪 · Cesar Fernandez-Ramirez🇲🇽 · Miguel Albaladejo🇺🇸 · Vincent Mathieu🇪🇸 · Victor I. Mokeev🇺🇸 · Adam P. Szczepaniak🇺🇸

   We investigate the properties of the hidden charm pentaquark-like resonances first observed by LHCb in 2015, by measuring the polarization transfer KLL between the incident photon and the outgoing proton in the exclusive photoproduction of J/psi near threshold. We present a first estimate of the sensitivity of this observable to the pentaquark photocouplings and hadronic branching ratios, and extend our predictions to the case of initial state helicity correlation ALL, using a polarized target. These results serve as a benchmark for the SBS experiment at Jefferson Lab, which proposes to measure for the first time the helicity correlations ALL and KLL in J/psi exclusive photoproduction, in order to determine the pentaquark photocouplings and branching ratios.

   ↳ hep-phhep-exnucl-exPRD(2019)·45 citations
9. 09*

   The MPGD-Based Photon Detectors for the upgrade of COMPASS RICH-1

   J. Agarwala · M. Alexeev · C.D.R. Azevedo · F. Bradamante · A. Bressan · M. Buchele · M. Chiosso · C. Chatterjee · P. Ciliberti · S. Dalla Torre · S. Dasgupta · O. Denisov and 17 other authors

   After pioneering gaseous detectors of single photon for RICH applications using CsI solid state photocathodes in MWPCs within the RD26 collaboration and by the constructions for the RICH detector of the COMPASS experiment at CERN SPS, in 2016 we have upgraded COMPASS RICH by novel gaseous photon detectors based on MPGD technology. Four novel photon detectors, covering a total active area of 1.5~m${}^2$, have been installed in order to cope with the challenging efficiency and stability requirements of the COMPASS physics programme. They are the first application in an experiment of MPGD-based single photon detectors. All aspects of the upgrade are presented, including engineering, mass production, quality assessment and performance. Perspectives for further developments in the field of gaseous single photon detectors are also indicated.

   ↳ physics.ins-dethep-exnucl-exJ.Phys.Conf.Ser.(2020)·1 citation
10. 10*

    Perturbation Scheme for the Effective Nuclear Force

    Kun Ratha Kean · Takashi Nishikawa · Yoritaka Iwata🇯🇵

    Based on a systematic Hartree-Fock+BCS calculation, new perturbation scheme is proposed to modify the existing Skyrme-type effective nuclear force. Much attention is paid to have a better description of fission property of heavy nuclei. In terms of incorporating the nuclear medium effects on the fission barrier height more correctly, two typical Skyrme parameter sets (SkM* and SLy4) are modified. In conclusion, according to the comparison to experiments, the calculated fission barrier heights are improved by almost 90$\%$.

    ↳ nucl-thnucl-exJPS Conf.Proc.(2020)·2 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.