Publications

Order by: publication date number of citations

• Monte Carlo, fitting and Machine Learning for Tau leptons

  Vladimir Cherepanov, Elzbieta Richter-Was, Zbigniew Was

  SciPost Phys. Proc. 1, 018 (2019) · published 19 February 2019 | Toggle abstract · pdf

  Status of tau lepton decay Monte Carlo generator TAUOLA, and its main recent applications are reviewed. It is underlined, that in recent efforts on development of new hadronic currents, the multi-dimensional nature of distributions of the experimental data must be taken with a great care. Studies for H to tau tau; tau to hadrons indeed demonstrate that multi-dimensional nature of distributions is important and available for evaluation of observables where tau leptons are used to constrain experimental data. For that part of the presentation, use of the TAUOLA program for phenomenology of H and Z decays at LHC is discussed, in particular in the context of the Higgs boson parity measurements with the use of Machine Learning techniques. Some additions, relevant for QED lepton pair emission and electroweak corrections are mentioned as well.

  2 citations

• Superradiant instability and black resonators in AdS

  Takaaki Ishii

  SciPost Phys. Proc. 4, 008 (2021) · published 13 August 2021 | Toggle abstract · pdf

  Rapidly rotating Myers-Perry-AdS black holes are unstable against rotational superradiance. From the onset of the instability, cohomogeneity-1 black resonators are constructed in five-dimensional asymptotically AdS space. By using the cohomogeneity-1 metric, perturbations of the cohomogeneity-1 black resonators are also studied.

  2 citations

• The eikonal model of reactions involving exotic nuclei; Roy Glauber's legacy in today's nuclear physics

  Pierre Capel

  SciPost Phys. Proc. 3, 017 (2020) · published 25 February 2020 | Toggle abstract · pdf

  In this contribution, the eikonal approximation developed by Roy Glauber to describe high-energy quantum collisions is presented. This approximation has been-and still is-extensively used to analyse reaction measurements performed to study the structure of nuclei far from stability. This presentation focuses more particularly on the application of the eikonal approximation to the study of halo nuclei in modern nuclear physics. To emphasise Roy Glauber's legacy in today's nuclear physics, recent extensions of this model are reviewed.

  2 citations

• Intermittency in pp collisions at $\sqrt{s}=$ 0.9, 7 and 8 TeV from the CMS collaboration

  Z. Ong, P. Agarwal, H. W. Ang, A. H. Chan, C. H. Oh

  SciPost Phys. Proc. 10, 032 (2022) · published 11 August 2022 | Toggle abstract · pdf

  The intermittency-type fluctuations as outlined by Bialas and Peschanski in the 1980s is analysed in $pp$ collisions at $\sqrt{s}=$ 0.9, 7 and 8 TeV from the CMS collaboration at CERN. Our preliminary analysis shows that the intermittency exponents in the bin-averaged scaled factorial moments decrease in magnitude with increasing collision energy at the TeV scale, which suggests that the cascading nature of multiparticle production described by the $\alpha$-model is weakening. We outline possible areas planned for future studies.

  2 citations

• On the discrepancy between the FOPT and CIPT approaches for hadronic tau spectral function moments

  Andre H. Hoang, Christoph Regner

  SciPost Phys. Proc. 7, 005 (2022) · published 20 June 2022 | Toggle abstract · pdf

  The discrepancy between the FOPT and CIPT approaches for hadronic tau spectral function moments constitutes the major theoretical uncertainty for strong coupling determinations from tau decay data. We show that the discrepancy can be analytically understood since the Borel representations -- which have been assumed to be identical for both approaches previously -- differ in the presence of IR renormalons. This implies that the OPE condensate corrections are different for both approaches and that the discrepancy may eventually be reconciled. In the talk we explain the difference and some mathematical aspects of the FOPT and CIPT Borel representations and show numerical results.

  2 citations

• CORSIKA 8 - the next-generation air shower simulation framework

  Tim Huege for the CORSIKA 8 Collaboration

  SciPost Phys. Proc. 13, 028 (2023) · published 29 September 2023 | Toggle abstract · pdf

  For more than 20 years, the community has heavily relied on CORSIKA for the simulation of extensive air showers, their Cherenkov light emission and their radio signals. While tremendously successful, the Fortran-based monolithic design of CORSIKA up to version 7 limits adaptation to new experimental needs, for example, in complex scenarios where showers transition from air into dense media, and to new computing paradigms such as the use of multi-core and GPU parallelization. With CORSIKA 8, we have reimplemented the core functionality of CORSIKA in a modern, modular, C++-based simulation framework, and successfully validated it against CORSIKA 7. Here, we discuss the philosophy of CORSIKA 8, showcase some example applications, and present the current state of implementation as well as the plans for the future.

  2 citations

• Classical boundary field theory of Jacobi sigma models by Poissonization

  Ion V. Vancea

  SciPost Phys. Proc. 4, 011 (2021) · published 13 August 2021 | Toggle abstract · pdf

  In this paper, we are going to construct the classical field theory on the boundary of the embedding of $\mathbb{R} \times S^{1}$ into the manifold $M$ by the Jacobi sigma model. By applying the poissonization procedure and by generalizing the known method for Poisson sigma models, we express the fields of the model as perturbative expansions in terms of the reduced phase space of the boundary. We calculate these fields up to the second order and illustrate the procedure for contact manifolds.

  2 citations

• Primary cosmic ray energy spectrum and mean mass composition using data from the TAIGA astrophysical complex

  V. Prosin, I. Astapov, P. Bezyazeekov, E. Bonvech, A. Borodin, A. Bulan, A. Chiavassa, D. Chernov, A. Dyachok, A. Gafarov, A. Garmash, V. Grebenyuk, O. Gress, E. Gress, T. Gress, A. Grinyuk, O. Grishin, A. D. Ivanova, A. L. Ivanova, N. Kalmykov, V. Kindin, S. Kiryuhin, R. Kokoulin, K. Kompaniets, E. Korosteleva, V. Kozhin, E. Kravchenko, A. Kryukov, L. Kuzmichev, A. Lagutin, M. Lavrova, Y. Lemeshev, B. Lubsandorzhiev, N. Lubsandorzhiev, A. Lukanov, D. Lukyantsev, S. Malakhov, R. Mirgazov, R. Monkhoev, E. Okuneva, E. Osipova, A. Pakhorukov, A. Pan, L. Panasenko, L. Pankov, A. D. Panov, A. Petrukhin, I. Poddubny, D. Podgrudkov, V. Poleschuk, V. Ponomareva, E. Popova, E. Postnikov, V. Ptuskin, A. Pushnin, R. Raikin, A. Razumov, G. Rubtsov, E. Ryabov, Y. Sagan, V. Samoliga, A. Silaev, A. Silaev, A. Sidorenkov, A. Skurikhin, A. Sokolov, L. Sveshnikova, V. Tabolenko, A. Tanaev, B. Tarashchansky, M. Y. Ternovoy, L. Tkachev, R. Togoo, N. Ushakov, A. Vaidyanathan, P. Volchugov, N. Volkov, D. Voronin, A. Zagorodnikov, A. Zhaglova, D. Zhurov, I. Yashin

  SciPost Phys. Proc. 13, 037 (2023) · published 29 September 2023 | Toggle abstract · pdf

  The corrected dependence of the mean depth of the EAS maximum $X_{max}$ on the energy was obtained from the data of the Tunka-133 array for 7 years and the TAIGA-HiSCORE array for 2 years. The parameter $\langle\ln A\rangle$, characterizing the mean mass compositon was derived from these results. The differential energy spectrum of primary cosmic rays in the energy range of $2\cdot 10^{14}$ – $2\cdot 10^{16}$ eV was reconstructed using the new parameter $Q_{100}$ the Cherenkov light flux at the core distance 100 m. Change of the parameter for the energy reconstuction for the TAIGA-HiSCORE from $Q_{200}$ to $Q_{100}$ provides a decreasing energy threshold for the spectrum to about 200 TeV.

  2 citations

• The pion beta and radiative electronic decays

  Dinko Počanić

  SciPost Phys. Proc. 5, 024 (2021) · published 6 September 2021 | Toggle abstract · pdf

  As the lightest meson, pion offers unique opportunities for measuring parameters and testing limits of the Standard Model (SM). The PiBeta experiment, carried out at PSI, focused on SM tests accessible through the pion beta, π + → π 0 e + ν e (γ), and electronic radiative, π + → e + ν e γ, decay channels. We review the PiBeta experiment, and update the pion beta decay branching ratio B πβ^exp = 1.038(6) tot × 10 −8 , along with the corresponding derived value of the Cabibbo-Kobayashi-Maskawa matrix element V ud = 0.9738(28).

  2 citations

• The SINDRUM-I Experiment

  Ralph Eichler, Christoph Grab

  SciPost Phys. Proc. 5, 007 (2021) · published 6 September 2021 | Toggle abstract · pdf

  SINDRUM-I was the first nearly 4 spectrometer at SIN. It was initially designed to 9 search for the forbidden decay + ! e+e􀀀e+ , but also successfully studied various 10 other processes with high precision. The upper limit obtained for the branching ratio of B!3e = 􀀀 (+ ! e+e􀀀e+ )=􀀀 (+ ! e+e¯ 11  ) < 1.0  10􀀀12(90% CL) from 1988 is still the best. The first statistically significant observation of the rare decay + ! e+e􀀀e+e¯ 12  , achieved in 1985, yielded a branching ratio of B13 !3e2 = (3.40.20.2)10􀀀5. Several 14 othermeasurements of rare decays were undertaken: the first observation of the -decay 15 + !e+ee􀀀e+ resulted in 􀀀 (+ !e+ee􀀀e+ )=􀀀 (+ !+ ) = (3.2  0.5  0.2)  10􀀀9, 16 also still the best measurement; and a determination of the ratio of the weak axial- to 17 vector-form factor FA=FV = (0.7  0.5), resolving an ambiguity. In addition, upper limits 18 for + ! e+ and + ! e+e with subsequent decay ! e+e􀀀 (search for "massless" Goldstone bosons) and 0 !e+e􀀀 19 < 1.3  10􀀀7 were obtained.

  2 citations