Publications

Order by: publication date number of citations

• Vision for QCD to the 2030s and Beyond

  George Sterman

  SciPost Phys. Proc. 8, 156 (2022) · published 14 July 2022 | Toggle abstract · pdf

  In this closing talk, I review some of the lessons we've learned about quantum chromodynamics, and reflect on what we may hope to learn in the coming years.

  1 citation

• Attenuation of cosmic-ray up-scattered dark matter

  Helena Kolesova

  SciPost Phys. Proc. 12, 055 (2023) · published 5 July 2023 | Toggle abstract · pdf

  GeV-scale dark matter particles with strong coupling to baryons evade the standard direct detection limits as they are efficiently stopped in the overburden and, consequently, are not able to reach the underground detectors. On the other hand, it has been shown that it is possible to probe this parameter space taking into account the flux of dark matter particles boosted by interactions with cosmic rays. We revisit these bounds paying particular attention to interactions of the relativistic dark matter particles in the Earth's crust. The effects of nuclear form factors, inelastic scattering and extra dependence of the cross section on transferred momentum (e.g. due to presence of light mediators) are studied and are found to be crucial for answering the question as to whether the window for GeV-scale strongly interacting dark matter is closed or not.

  1 citation

• Pion GPDs: Constraints, modelling and experimental access

  Jose Manuel Morgado Chávez

  SciPost Phys. Proc. 8, 165 (2022) · published 14 July 2022 | Toggle abstract · pdf

  The study of Generalised Parton Distributions is a hot-topic in hadron physics. Due to its connection with chiral symmetry breaking, assessing those of pions is of great interest. For this reason, we present a novel model-building strategy for pion GPDs capable of fulfilling all of the theoretical constraints required by QCD: support, polynomiality, positivity and soft-pion theorem. The methodology is illustrated with a simple model, and exploited afterwards for the calculation of pions' deeply virtual Compton Scattering (DVCS) Compton Form Factors (CFFs) at NLO. The results show gluon-content to play the dominant role in pions' response to DVCS at EIC kinematics.

  1 citation

• Theoretical study of deeply virtual Compton scattering off $^4$He

  Sara Fucini, Sergio Scopetta, Michele Viviani

  SciPost Phys. Proc. 3, 012 (2020) · published 24 February 2020 | Toggle abstract · pdf

  An interesting breakthrough in understanding the elusive inner content of nuclear systems in terms of partonic degrees of freedom is represented by deeply virtual Compton scattering processes. In such a way, tomographic view of nuclei and bound nucleons in coordinate space could be achieved for the first time. Moreover, nowadays experimental results for such a process considering $^4$He targets recently released at Jefferson Lab are available. In this talk, the recent results of our rigorous Impulse Approximation for DVCS off $^4$He, in terms of state-of-the-art models of the nuclear spectral function and of the parton structure of the bound proton, able to explain present data, has been shown.

  1 citation

• Particle Physics at PSI

  A. Signer, K. Kirch, C. M. Hoffman

  SciPost Phys. Proc. 5, 001 (2021) · published 6 September 2021 | Toggle abstract · pdf

  Particle physics results of constant value and significant impact have been obtained at PSI, and several efforts are presently ongoing and expected to deliver new findings in the near future. In this special SciPost volume we collect them together in a concise manner. Not yet included are ideas for future facility upgrades or completely new experimental efforts, but we are set to extend this volume in the years to come.

  1 citation

• Correlations among 3N observables

  Yuriy Volkotrub, Jacek Golak, Roman Skibiński, Kacper Topolnicki, Henryk Witała

  SciPost Phys. Proc. 3, 055 (2020) · published 27 February 2020 | Toggle abstract · pdf

  We use a correlation matrix of two-nucleon (2N) potential parameters to investigate correlations among three-nucleon (3N) observables for the elastic nucleon-deuteron (Nd) scattering process. We employ the up-to-date 2N semilocal momentum-space regularized chiral interactions and the phenomenological OPE-Gaussian potential and using the Faddeev formalism we calculate 3N observables and their correlations. As an example, we present the correlation between the differential cross section and the deuteron analyzing power T20.

  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

• Light Nuclei Production in Au+Au Collisions at $\sqrt{s_{\mathrm{NN}}}$ = 3 GeV from the STAR experiment

  Hui Liu

  SciPost Phys. Proc. 10, 040 (2022) · published 11 August 2022 | Toggle abstract · pdf

  Light nuclei production is expected to be sensitive to baryon density fluctuations and can be used to probe the signatures of QCD critical point and/or a first-order phase transition in heavy-ion collisions. In this proceedings, we present the spectra and yields of protons ($p$) and light nuclei ($d$, $t$, $^{3}\mathrm{He}$, $^{4}\mathrm{He}$) in Au+Au collisions at $\sqrt{s_{\mathrm{NN}}}$ = 3 GeV by the STAR experiment. Finally, it is found that the kinetic freeze-out dynamics (temperature $T_{kin}$ $vs.$ average radial flow velocity $\langle\beta_{T}\rangle$) at 3 GeV extracted with the blast-wave model deviate from the trends at high energies ($\sqrt{s_{\mathrm{NN}}}$ = 7.7 - 200 GeV), indicating a different medium equation of state.

  1 citation

• $τ$ lepton mass measurement at BESIII

  Jianyong Zhang on behalf of BESIII collaboration

  SciPost Phys. Proc. 1, 004 (2019) · published 18 February 2019 | Toggle abstract · pdf

  In order to obtain the mass of $\tau$ lepton at BESIII precisely, a beam energy measurement system was built at BEPCII. A scenario for high precision $\tau$ mass measurement was put forth before data taken. More than 130 $pb^{-1}$ $\tau$ mass scan data were collected in April 2018, and the uncertainty of $m_{\tau}$ is expected to be less than 100 keV.

  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