Publications

Order by: publication date number of citations

• Disentangling sub-GeV dark matter from the diffuse supernova neutrino background using Hyper-Kamiokande

  Sandra Robles

  SciPost Phys. Proc. 12, 065 (2023) · published 5 July 2023 | Toggle abstract · pdf

  The upcoming Hyper-Kamiokande (HyperK) experiment is expected to detect the Diffuse Supernova Neutrino Background (DSNB). This requires to ponder all possible sources of background. Sub-GeV dark matter (DM) which annihilates into neutrinos is a potential background that has not been considered so far. We simulate DSNB and DM signals, as well as backgrounds in the HyperK detector. We find that DM-induced neutrinos could indeed alter the extraction of the correct values of the parameters of interest for DSNB physics. Since the DSNB is an isotropic signal, and DM originates primarily from the Galactic centre, we show that this effect could be alleviated with an on-off analysis.

  1 citation

• Theory of kinetically-constrained-models dynamics

  Gianmarco Perrupato, Tommaso Rizzo

  SciPost Phys. 18, 020 (2025) · published 17 January 2025 | Toggle abstract · pdf

  The mean-field theory of Kinetically-Constrained-Models is developed by considering the Fredrickson-Andersen model on the Bethe lattice. Using certain properties of the dynamics observed in actual numerical experiments we derive asymptotic dynamical equations equal to those of Mode-Coupling-Theory. Analytical predictions obtained for the dynamical exponents are successfully compared with numerical simulations in a wide range of models, including the case of generic values of the connectivity and the facilitation, random pinning and fluctuating facilitation. The theory is thus validated for both continuous and discontinuous transitions and also in the case of higher order critical points characterized by logarithmic decays.

  1 citation

• Single crystal growth of PrNiGe$_2$ compounds

  Kousei Ishiwatari, Kaito Hoshii, Keisuke Ida, Masashi Ohashi

  SciPost Phys. Proc. 11, 002 (2023) · published 5 June 2023 | Toggle abstract · pdf

  We report on the magnetic characterization of a praseodym intermetallic PrNiGe$_2$. Several single crystals are grown by the Czochralski method from Ni- deficient sample as the initial one. X-ray analysis of PrNi$_{0.8}$Ge$_2$ indicated the CeNiSi$_2$-type structure as the only phase. The magnetic measurements clearly indicate that PrNi$_x$Ge$_2$ exhibits a ferromagnetic orderings at 12 K, which is independent with of composition of Ni. A strong anisotropy along the three principal crystallographic directions was observed, reflecting the orthorhombic symmetry of the crystal structure. The $b$-axis was found to be the easy axis of magnetization.

  1 citation

• Codebase release 1.1 for TASEPy

  Luca Ciandrini, Richmond L. Crisostomo, Juraj Szavits-Nossan

  SciPost Phys. Codebases 22-r1.1 (2023) · published 13 December 2023 | Toggle abstract · src

  The totally asymmetric simple exclusion process (TASEP) is a paradigmatic lattice model for one-dimensional particle transport subject to excluded-volume interactions. Solving the inhomogeneous TASEP in which particles' hopping rate vary across the lattice is a long-standing problem. In recent years, a power series approximation (PSA) has been developed to tackle this problem, however no computer algorithm currently exists that implements this approximation. This paper addresses this issue by providing a Python-based package TASEPy that finds the steady state solution of the inhomogeneous TASEP for any set of hopping rates using the PSA truncated at a user-defined order.

  1 citation

• Scattering from an external field in quantum chromodynamics at high energies: From foundations to interdisciplinary connections

  Athanasia-Konstantina Angelopoulou, Anh Dung Le, Stéphane Munier

  SciPost Phys. Lect. Notes 92 (2025) · published 12 March 2025 | Toggle abstract · pdf

  We review the factorization of the $S$-matrix elements in the context of particle scattering off an external field, which can serve as a model for the field of a large nucleus. The factorization takes the form of a convolution of light cone wave functions describing the physical incoming and outgoing states in terms of bare partons, and products of Wilson lines. The latter represent the interaction between the bare partons and the external field. Specializing to elastic scattering amplitudes of onia at very high energies, we introduce the color dipole model, which formulates the calculation of the modulus-squared of the wave functions in quantum chromodynamics with the help of a branching random walk, and the scattering amplitudes as observables on this classical stochastic process. Methods developed for general branching processes produce analytical formulas for the asymptotics of such observables, and thus enable one to derive exact large-rapidity expressions for onium-nucleus cross sections, from which electron-nucleus cross sections may be inferred.

  1 citation

• Invariants of winding-numbers and steric obstruction in dynamics of flux lines

  Olivier Cépas, Peter M. Akhmetiev

  SciPost Phys. 7, 032 (2019) · published 12 September 2019 | Toggle abstract · pdf

  We classify the sectors of configurations that result from the dynamics of 2d crossing flux lines, which are the simplest degrees of freedom of the 3-coloring lattice model. We show that the dynamical obstruction is the consequence of two effects: (i) conservation laws described by a set of invariants that are polynomials of the winding numbers of the loop configuration, (ii) steric obstruction that prevents paths between configurations, for lack of free space. We argue that the invariants fully classify the configurations in five, chiral and achiral, sectors and no further obstruction in the limit of low-winding numbers.

  1 citation

• Can quantized fragmentation replace colour reconnection models?

  Šárka Todorova-Nová

  SciPost Phys. Proc. 15, 001 (2024) · published 2 April 2024 | Toggle abstract · pdf

  A brief overview of properties of the model of quantized fragmentation of a helical QCD string is followed by the discussion of colour reconnection models and of the ways to reproduce the evolution of the average transverse momentum in hadronic events, as function of charged particle multiplicity. Reference to recent experimental data is included.

  1 citation

• Tapered amplifier laser with frequency-shifted feedback

  A. Bayerle, S. Tzanova, P. Vlaar, B. Pasquiou, F. Schreck

  SciPost Phys. 1, 002 (2016) · published 22 October 2016 | Toggle abstract · pdf

  We present a frequency-shifted feedback (FSF) laser based on a tapered amplifier. The laser operates as a coherent broadband source with up to 370GHz spectral width and 2.3us coherence time. If the FSF laser is seeded by a continuous-wave laser a frequency comb spanning the output spectrum appears in addition to the broadband emission. The laser has an output power of 280mW and a center wavelength of 780nm. The ease and flexibility of use of tapered amplifiers makes our FSF laser attractive for a wide range of applications, especially in metrology.

  1 citation

• Codebase release 1.1 for GAPS

  Michael H. Seymour, Siddharth Sule

  SciPost Phys. Codebases 33-r1.1 (2024) · published 12 August 2024 | Toggle abstract · src

  The Single Instruction, Multiple Thread (SIMT) paradigm of GPU programming does not support the branching nature of a parton shower algorithm by definition. However, modern GPUs are designed to schedule threads with diverging processes independently, allowing them to handle such branches. With regular thread synchronisation and careful treatment of the individual steps, one can simulate a parton shower on a GPU. We present a Sudakov veto algorithm designed to simulate parton branching on multiple events in parallel. We also release a CUDA C++ program that generates matrix elements, showers partons and computes jet rates and event shapes for LEP at 91.2 GeV on a GPU. To benchmark its performance, we also provide a near-identical C++ program designed to simulate events serially on a CPU. While the consequences of branching are not absent, we demonstrate that a GPU can provide the throughput of a many-core CPU. As an example, we show that the time taken to shower $10^6$ events on one NVIDIA TESLA V100 GPU is equivalent to that of 295 Intel Xeon E5-2620 CPU cores.

  1 citation

• First measurement results from DANAE - Demonstrating DePFET RNDR on a prototype Matrix

  Alexander Bähr, Holger Kluck, Peter Lechner, Jelena Ninkovic, Jochen Schiek, Hexi Shi, Wolfgang Treberspurg, Johannes Treis

  SciPost Phys. Proc. 12, 066 (2023) · published 5 July 2023 | Toggle abstract · pdf

  In the search for dark matter particle candidates, the mass region below 1 GeV/c$^2$ is relatively unprobed. Utilizing a low-noise silicon sensor as a sensitive target material, we aim to study the event signature of recoils between dark matter candidates and bound electrons. As the deposited energy is only a few eV, a sensor capable of detecting these low signals is required. We present first measurements on a prototype pixel matrix. It is based on the RNDR DePFET principle and provides a deep sub-electron readout noise of 0.2e$^-$ and below.

  1 citation