Publications

Order by: publication date number of citations

• An accurate allowance for initial and final state interactions in the treatment of the alpha-alpha Bremsstrahlung

  Adam M. Arslanaliev, Aleksandr V. Shebeko

  SciPost Phys. Proc. 3, 042 (2020) · published 27 February 2020 | Toggle abstract · pdf

  The alpha-alpha bremsstrahlung is studied using the generalization of the Siegert theorem. The corresponding amplitude is written in the gauge invariant form. Special attention is paid to taking into account the Coulomb interaction. Some correlation function is found and its dependence on the strong interaction is discussed.

  1 citation

• Proton penetration efficiency over a high altitude observatory in Mexico

  S. Miyake, T. Koi, Y. Muraki, Y. Matsubara, S. Masuda, P. Miranda, T. Naito, E. Ortiz, A. Oshima, T. Sakai, T. Sako, S. Shibata, H. Takamaru, M. Tokumaru, J. F. Valdés-Galicia

  SciPost Phys. Proc. 13, 001 (2023) · published 28 September 2023 | Toggle abstract · pdf

  In association with a large solar flare on November 7, 2004, the solar neutron detectors located at Mt. Chacaltaya (5,250 m) in Bolivia and Mt. Sierra Negra (4,600 m) in Mexico recorded very interesting events. In order to explain these events, we have performed a calculation solving the equation of motion of anti-protons inside the magnetosphere. Based on these results, the Mt. Chacaltaya event may be explained by the detection of solar neutrons, while the Mt. Sierra Negra event may be explained by the first detection of very high energy solar neutron decay protons (SNDPs) around 6 GeV.

  1 citation

• The inversion of the Lorentz integral transform with controlled resolution

  Winfried Leidemann, Victor D. Efros, Veronica Yu. Shalamova

  SciPost Phys. Proc. 3, 037 (2020) · published 26 February 2020 | Toggle abstract · pdf

  The Lorentz integral transform (LIT) method is briefly presented. The ill-posedness of the inversion is discussed and it is pointed out that the LIT is an integral transform with a controlled resolution. As application the dipole response of a three-particle system bound in a hypercentral potential is considered. The inversion is performed in two ways, both employ expansions of the response function and of the LIT on a basis set and a transformed basis set, respectively. A previous study of the process under consideration seemed to point to serious problems in the inversion process. In the present work, however, it is shown that the LIT approach can be carried out in a reliable way.

  1 citation

• Cracking hadron and nuclear collisions open with ropes and string shoving in PYTHIA8

  Smita Chakraborty

  SciPost Phys. Proc. 10, 017 (2022) · published 10 August 2022 | Toggle abstract · pdf

  Enhancement in strangeness yields in heavy-ion collisions is regarded as one of the attributes of the Quark-Gluon Plasma (QGP) along with jet quenching and final-state collectivity. To reproduce these effects in the MC implementation of the Lund string model in \pythia, the inclusion of non-perturbative mechanisms like string shoving and rope hadronization is crucial. In this proceeding, we discuss our latest implementation of these mechanisms and the preliminary results for the strangeness enhancement in high-multiplicity p-p, p-Pb and Xe-Xe. We conclude with remarks on the ongoing development of the model.

  1 citation

• Chiral symmetry restoration with three chiral partners

  Juan M. Torres-Rincon

  SciPost Phys. Proc. 6, 015 (2022) · published 31 May 2022 | Toggle abstract · pdf

  I discuss the masses of chiral partners in the context of chiral symmetry restoration at finite temperature. Using the Nambu–Jona-Lasinio model I first remind the usual situation where two mesons of opposed parity become degenerate above the chiral transition temperature. Then I consider an effective theory for D mesons where the positive parity companion presents a “double pole structure”. In this case three different masses need to be analyzed as functions of the temperature. I suggest a possible restoration pattern at high temperatures when the back-reaction of the quark condensate is incorporated.

  1 citation

• Gluon pseudo-distributions at short distances

  I. Balitsky, W. Morris, A. Radyushkin

  SciPost Phys. Proc. 8, 161 (2022) · published 14 July 2022 | Toggle abstract · pdf

  We present the results that are necessary in the ongoing lattice calculations of the gluon parton distribution functions (PDFs) within the pseudo-PDF approach. We identify the two-gluon correlator functions that contain the invariant amplitude determining the gluon PDF in the light-cone $z^2 \to 0$ limit, and perform one-loop calculations in the coordinate representation in an explicitly gauge-invariant form. Ultraviolet (UV) terms, which contain $\ln (-z^2)$-dependence cancel in the reduced Ioffe-time distribution (ITD), and we obtain the matching relation between the reduced ITD and the light-cone ITD. Using a kernel form, we get a direct connection between lattice data for the reduced ITD and the normalized gluon PDF.

  1 citation

• Highlights from the Telescope Array Experiment

  Hiroyuki Sagawa for the Telescope Array Collaboration

  SciPost Phys. Proc. 13, 041 (2023) · published 29 September 2023 | Toggle abstract · pdf

  The Telescope Array (TA) is the largest hybrid cosmic ray detector in the Northern Hemisphere, which observes primary particles in the energy range from 2 PeV to 100 EeV. The main TA detector consists of 507 plastic scintillation counters on a 1.2-km spacing square grid and fluorescence detectors at three stations overlooking the sky above the surface detector array. The TA Low energy Extension (TALE) detector, which consists of ten fluorescence telescopes, and 80 infill surface detectors with 400m and 600 m spacing, has continued to provide stable observations since its construction completion in 2018. The TAx4, a plan to quadruple the detection area of TA is also ongoing. About half of the planned surface detectors have been deployed, and the current TAx4 continues to operate stably as a hybrid detector. I review the present status of the TA experiment and the recent results on the cosmic-ray anisotropy, mass composition and energy spectrum.

  1 citation

• Nucleon axial form factors from lattice QCD

  Constantia Alexandrou

  SciPost Phys. Proc. 6, 006 (2022) · published 31 May 2022 | Toggle abstract · pdf

  We give an overview on the evaluation of the axial and pseudoscalar form factors of the nucleon within the lattice QCD formulation. We discuss recent results obtained from the analysisofNf =2+1+1twistedmassfermiongaugeensemblesgeneratedatphysical values of the pion mass. Besides evaluating the isovector form factors, and the PCAC and Goldberger-Treiman relations, we also discuss results for the strange and charm axial form factors. We provide a comparison with other recent lattice QCD results obtained with different discretization schemes of the fermion action.

  1 citation

• Nuclear matter effects on jet production at electron-ion colliders

  Hai Tao Li, Ze Long Liu, Ivan Vitev

  SciPost Phys. Proc. 8, 134 (2022) · published 14 July 2022 | Toggle abstract · pdf

  In these proceedings we report recent progress on understanding hadron and jet production in electron-nucleus collisions at the future Electron-Ion Collider [1,2]. These processes will play an essential role in the exploration of the partonic structure of nuclei and the study of parton shower evolution in strongly-interacting matter. We employ the framework of soft-collinear effective theory, generalized to include in-medium interactions, to present the first theoretical results for inclusive hadron and jet cross sections, as well as the jet charge modification in deep inelastic scattering on nuclei. We further demonstrate how to separate initial-state and final-state effects.

  1 citation

• Even lighter particle dark matter

  Alvaro E. Chavarria

  SciPost Phys. Proc. 12, 001 (2023) · published 3 July 2023 | Toggle abstract · pdf

  We report on recent progress in the search for dark matter particles with masses from 1 Mev to 1 Gev . Several dark matter candidates in this mass range are expected to generate measurable electronic-recoil signals in direct-detection experiments. We focus on dark matter particles scattering with electrons in semiconductor detectors since they have fundamentally the highest sensitivity due to their low ionization threshold. Charge-coupled device (CCD) silicon detectors are the leading technology, with significant progress expected in the coming years. We present the status of the CCD program and briefly report on other efforts.

  1 citation