Publications

Order by: publication date number of citations

• Recent results from the TOTEM collaboration and the discovery of the odderon

  Christophe Royon

  SciPost Phys. Proc. 13, 005 (2023) · published 28 September 2023 | Toggle abstract · pdf

  We describe the most recent results from the TOTEM collaboration on elastic, inelastic and total cross sections as well as the odderon discovery by the D0 and TOTEM collaborations.

  1 citation

• Muon puzzle in inclined muon bundles detected by NEVOD-DECOR

  A. G. Bogdanov, N. S. Barbashina, S. S. Khokhlov, V. V. Kindin, R. P. Kokoulin, K. G. Kompaniets, A. Y. Konovalova, G. Mannocchi, A. A. Petrukhin, V. V. Shutenko, G. Trinchero, V. S. Vorobev, I. I. Yashin, E. A. Yurina, E. A. Zadeba

  SciPost Phys. Proc. 13, 003 (2023) · published 28 September 2023 | Toggle abstract · pdf

  The data of cosmic ray NEVOD-DECOR experiment on the investigation of inclined muon bundles for a long time period (May 2012 - March 2021) are presented. The analysis showed that the observed intensity of muon bundles at primary cosmic ray energies of about 1 EeV and higher can be compatible with the expectation in frame of widely used hadron interaction models only under the assumption of an extremely heavy mass composition. This conclusion is consistent with data of several experiments on investigations of muon content in air showers, but contradicts the available fluorescence data on $X_{\text{max}}$ which favor a light mass composition at these energies. In order to clarify the nature of the "muon puzzle", investigations of the muon bundle energy deposit in the detector material were carried out. For the first time, experimental estimates of the average energy of muons in the bundles of inclined air showers initiated by primary particles with energies from 10 to 1000 PeV have been obtained.

• Cosmic ray measurements with IceCube and IceTop

  Dennis Soldin (for the IceCube Collaboration)

  SciPost Phys. Proc. 13, 002 (2023) · published 28 September 2023 | Toggle abstract · pdf

  IceCube is a cubic-kilometer Cherenkov detector in the deep ice at the geographic South Pole. The dominant event yield in the deep ice detector consists of penetrating atmospheric muons with energies above approximately 300 GeV, produced in cosmic ray air showers. In addition, the surface array, IceTop, measures the electromagnetic component and GeV muons of air showers. Hence, IceCube and IceTop yield unique opportunities to study cosmic rays with unprecedented statistics in great detail. We will present recent results of comic ray measurements from IceCube and IceTop. In this overview, we will highlight measurements of the energy spectrum of cosmic rays from 250 TeV up to the EeV range and their mass composition above 3 PeV. We will also report recent results from measurements of the muon content in air showers and discuss their consistency with predictions from current hadronic interaction models.

• 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

• Unweighting multijet event generation using factorisation-aware neural networks

  Timo Janßen, Daniel Maître, Steffen Schumann, Frank Siegert, Henry Truong

  SciPost Phys. 15, 107 (2023) · published 21 September 2023 | Toggle abstract · pdf

  In this article we combine a recently proposed method for factorisation-aware matrix element surrogates with an unbiased unweighting algorithm. We show that employing a sophisticated neural network emulation of QCD multijet matrix elements based on dipole factorisation can lead to a drastic acceleration of unweighted event generation. We train neural networks for a selection of partonic channels contributing at the tree-level to $Z+4,5$ jets and $t\bar{t}+3,4$ jets production at the LHC which necessitates a generalisation of the dipole emulation model to include initial state partons as well as massive final state quarks. We also present first steps towards the emulation of colour-sampled amplitudes. We incorporate these emulations as fast and accurate surrogates in a two-stage rejection sampling algorithm within the SHERPA Monte Carlo that yields unbiased unweighted events suitable for phenomenological analyses and post-processing in experimental workflows, e.g. as input to a time-consuming detector simulation. For the computational cost of unweighted events we achieve a reduction by factors between $16$ and $350$ for the considered channels.

  12 citations

• Diffusion of muonic hydrogen in hydrogen gas and the measurement of the 1$s$ hyperfine splitting of muonic hydrogen

  J. Nuber, A. Adamczak, M. Abdou Ahmed, L. Affolter, F. D. Amaro, P. Amaro, A. Antognini, P. Carvalho, Y. -H. Chang, T. -L. Chen, W. -L. Chen, L. M. P. Fernandes, M. Ferro, D. Goeldi, T. Graf, M. Guerra, T. W. Hänsch, C. A. O. Henriques, M. Hildebrandt, P. Indelicato, O. Kara, K. Kirch, A. Knecht, F. Kottmann, Y. -W. Liu, J. Machado, M. Marszalek, R. D. P. Mano, C. M. B. Monteiro, F. Nez, A. Ouf, N. Paul, R. Pohl, E. Rapisarda, J. M. F. dos Santos, J. P. Santos, P. A. O. C. Silva, L. Sinkunaite, J. -T. Shy, K. Schuhmann, S. Rajamohanan, A. Soter, L. Sustelo, D. Taqqu, L. -B. Wang, F. Wauters, P. Yzombard, M. Zeyen, J. Zhang

  SciPost Phys. Core 6, 057 (2023) · published 23 August 2023 | Toggle abstract · pdf

  The CREMA collaboration is pursuing a measurement of the ground-state hyperfine splitting (HFS) in muonic hydrogen ($\mu$p) with 1 ppm accuracy by means of pulsed laser spectroscopy. In the proposed experiment, the $\mu$p atom is excited by a laser pulse from the singlet to the triplet hyperfine sub-levels, and is quenched back to the singlet state by an inelastic collision with a H$_2$ molecule. The resulting increase of kinetic energy after this cycle modifies the $\mu$p atom diffusion in the hydrogen gas and the arrival time of the $\mu$p atoms at the target walls. This laser-induced modification of the arrival times is used to expose the atomic transition. In this paper we present the simulation of the $\mu$p diffusion in the H$_2$ gas which is at the core of the experimental scheme. These simulations have been implemented with the Geant4 framework by introducing various low-energy processes including the motion of the H$_2$ molecules, i.e. the effects related with the hydrogen target temperature. The simulations have been used to optimize the hydrogen target parameters (pressure, temperatures and thickness) and to estimate signal and background rates. These rates allow to estimate the maximum time needed to find the resonance and the statistical accuracy of the spectroscopy experiment.

  5 citations

• Codebase release 0.4 for pyBumpHunter

  Louis Vaslin, Samuel Calvet, Vincent Barra, Julien Donini

  SciPost Phys. Codebases 15-r0.4 (2023) · published 14 July 2023 | Toggle abstract · src

  The BumpHunter algorithm is widely used in the search for new particles in High Energy Physics analysis. This algorithm offers the advantage of evaluating the local and global p-values of a localized deviation in the observed data without making any hypothesis on the supposed signal. The increasing popularity of the Python programming language motivated the development of a new public implementation of this algorithm in Python, called pyBumpHunter, together with several improvements and additional features. It is the first public implementation of the BumpHunter algorithm to be added to Scikit-HEP. This paper presents in detail the BumpHunter algorithm as well as all the features proposed in this implementation. All these features have been tested in order to demonstrate their behaviour and performance.

  1 citation

• pyBumpHunter: A model independent bump hunting tool in Python for high energy physics analyses

  Louis Vaslin, Samuel Calvet, Vincent Barra, Julien Donini

  SciPost Phys. Codebases 15 (2023) · published 14 July 2023 | Toggle abstract · pdf

  The BumpHunter algorithm is widely used in the search for new particles in High Energy Physics analysis. This algorithm offers the advantage of evaluating the local and global p-values of a localized deviation in the observed data without making any hypothesis on the supposed signal. The increasing popularity of the Python programming language motivated the development of a new public implementation of this algorithm in Python, called pyBumpHunter, together with several improvements and additional features. It is the first public implementation of the BumpHunter algorithm to be added to Scikit-HEP. This paper presents in detail the BumpHunter algorithm as well as all the features proposed in this implementation. All these features have been tested in order to demonstrate their behaviour and performance.

  5 citations

• The Belle II experiment: Status and prospects

  Kavita Lalwani (on behalf of the Belle II Collaboration)

  SciPost Phys. Proc. 8, 176 (2023) · published 11 July 2023 | Toggle abstract · pdf

  The Belle II experiment at the SuperKEKB energy asymmetric $e^{+}e^{-}$ collider is a substantial upgrade of the B factory facility at the Japanese KEK laboratory. The design luminosity of the machine is $6\times10^{35}$ $cm^{-2}s^{-1}$ and the Belle II experiment aims to record 50 $ab^{-1}$ of data, a factor of 50 more than its predecessor. With this data set, Belle II will be able to measure the Cabibbo-Kobayashi-Maskawa (CKM) matrix, the matrix elements and their phases, with unprecedented precision and explore flavor physics with $B$, charmed mesons, and $\tau$ leptons. Belle II has also a unique capability to search for low-mass dark matter and low-mass mediators. In this paper, we will review the status of the Belle II detector, SuperKEKB accelerator and the prospects for physics at Belle II.

• The DarkSide-20k TPC and underground argon cryogenic system

  Thomas N. Thorpe on behalf of the DS-20k collaboration

  SciPost Phys. Proc. 12, 069 (2023) · published 5 July 2023 | Toggle abstract · pdf

  DarkSide-20k (DS-20k) will exploit the physical and chemical properties of liquid argon (LAr) housed within a large dual-phase time project chamber (TPC) in its direct search for dark matter. The TPC will utilize a compact, integrated design with many novel features to enable the 20t fiducial volume of underground argon. Underground Argon (UAr) is sourced from underground CO$_2$ wells and depleted in the radioactive isotope $^{39}$Ar, greatly enhancing the experimental sensitivity to dark matter interactions. Sourcing and transporting the $\mathcal{O}$(100t) of UAr for (DS-20k) is costly, and a dedicated single-closed-loop cryogenic system has been designed, constructed, and tested to handle the valuable UAr. We present an overview of the (DS-20k) TPC design and the first results from the UAr cryogenic system.

  4 citations