Publications

Order by: publication date number of citations

• The all-particle energy spectrum of cosmic rays from 10 TeV to 1 PeV measured with HAWC

  Jorge A. Morales-Soto, Juan C. Arteaga-Velázquez on behalf of the HAWC Collaboration

  SciPost Phys. Proc. 13, 039 (2023) · published 29 September 2023 | Toggle abstract · pdf

  The HAWC observatory is an air-shower detector, which is designed to study both astrophysical gamma-rays in the TeV region and galactic cosmic rays in the energy interval from 1 TeV to 1 PeV. This energy regime is interesting for cosmic ray research, since indirect observations overlap with direct measurements, which offers the opportunity for cross calibration and studies of experimental systematic errors in both techniques. One quantity that could help for this purpose is the all-particle energy spectrum of cosmic rays. In this work, we present an update of HAWC measurements on the total cosmic-ray energy spectrum between 10 TeV and 1 PeV. The spectrum was obtained from an unfolding analysis of almost two years of HAWC's data, which was collected from January, 2018 to December, 2019. For the energy estimation, we employed the high-energy hadronic interaction model QGSJET-II-04. As in a previous work of HAWC, published in 2017, we observed the presence of a knee-like feature in the region of tens of TeV.

  3 citations

• Mulan: a part-per-million measurement of the muon lifetime and determination of the Fermi constant

  R. Carey, T. Gorringe, D.W. Hertzog

  SciPost Phys. Proc. 5, 016 (2021) · published 6 September 2021 | Toggle abstract · pdf

  The part-per-million measurement of the positive muon lifetime and determination of the Fermi constant by the MuLan experiment at the Paul Scherrer Institute is reviewed. The experiment used an innovative, time-structured, surface muon beam and a near-4π, finely-segmented, plastic scintillator positron detector. Two in-vacuum muon stopping targets were used: a ferromagnetic foil with a large internal magnetic field, and a quartz crystal in a moderate external magnetic field. The experiment acquired a dataset of 1.6e12 positive muon decays and obtained a muon lifetime τ_µ = 2 196 980.3(2.2) ps (1.0 ppm) and Fermi constant G_F = 1.166 378 7(6) × 10−5 GeV^−2 (0.5 ppm). The thirty fold improvement in τ_µ has proven valuable for precision measurements in nuclear muon capture and the commensurate improvement in G_F has proven valuable for precision tests of the standard model.

  3 citations

• Developments since Kira 2.0

  Fabian Lange, Philipp Maierhöfer, Johann Usovitsch

  SciPost Phys. Proc. 7, 017 (2022) · published 21 June 2022 | Toggle abstract · pdf

  Last year we released version 2.0 of the Feynman integral reduction program Kira. In this contribution we first report on changes and new features since then and, secondly, on new features for upcoming releases.

  3 citations

• The LHCspin project

  M. Santimaria, V. Carassiti, G. Ciullo, P. Di Nezza, P. Lenisa, S. Mariani, L. L. Pappalardo, E. Steffens

  SciPost Phys. Proc. 8, 050 (2022) · published 12 July 2022 | Toggle abstract · pdf

  Broad and unexplored kinematic regions can be accessed at the LHC with fixed-target $pp$, $pA$ and $PbA$ collisions at $\sqrt{s_{\rm{NN}}}=72-115~\rm{GeV}$. The LHCb detector is a fully-instrumented forward spectrometer able to run in fixed-target mode, and currently hosts a target gas cell to take data in the upcoming Run 3. The LHCspin project aims at extending this physics program to Run 4 and to bring polarised physics at the LHC. An overview of the physics potential and a description of the LHCspin experimental setup are presented.

  3 citations

• Cosmic ray interactions in the atmosphere: QGSJET-III and other models

  Sergey Ostapchenko

  SciPost Phys. Proc. 13, 004 (2023) · published 28 September 2023 | Toggle abstract · pdf

  The physics content of the QGSJET-III Monte Carlo generator of high energy hadronic collisions is discussed. New theoretical approaches implemented in QGSJET-III are addressed in some detail and a comparison to alternative treatments of other cosmic ray interaction models is performed. Calculated characteristics of cosmic ray-induced extensive air showers are presented and differences between the respective results of QGSJET-III and other models are analyzed. In particular, it is demonstrated that those differences are partly caused by severe deficiencies of the other interaction models.

  3 citations

• Direct searches of dark matter with the SABRE South experiment

  Madeleine J. Zurowski on behalf of the SABRE South Collaboration

  SciPost Phys. Proc. 12, 029 (2023) · published 4 July 2023 | Toggle abstract · pdf

  The SABRE (Sodium-iodide with Active Background REjection) South experiment is a direct dark matter detector, made of radio-pure NaI(Tl) crystals surrounded by a liquid scintillator veto. The achievement of ultra-low background rate is essential to provide a model independent test of the signal observed by the DAMA/LIBRA experiment whose claim has not been verified yet. The SABRE South experiment will be located at the Stawell Underground Physics Laboratory (SUPL), Australia, the first deep underground laboratory in the Southern Hemisphere. The laboratory will not only house rare event physics searches but also measurement facilities to support low background physics experiments and applications like radiobiology and quantum computing. The SABRE South detector commissioning is expected to occur in 2023. This paper details the setup and projections for the experiment, and a brief description of the underground laboratory.

  3 citations

• Status of the Muon g-2 experiment at Fermilab

  A. Driutti for the Muon g-2 Collaboration

  SciPost Phys. Proc. 1, 033 (2019) · published 21 February 2019 | Toggle abstract · pdf

  The aim of the Muon g − 2 Experiment at Fermilab (E989) is to measure the muon anomalous magnetic moment (aμ) with a relative precision of 140 parts- per-billion (ppb). This precision, which is a factor of four improvement from the current experimental result, will allow for a much more stringent test of the Standard Model. This paper present the current status of the experimental measurement of aμ after the first physics run.

  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

• Transport and magnetic properties in the Nd diluted system Y$_{1-x}$Nd$_{x}$Co$_{2}$Zn$_{20}$

  Rikako Yamamoto, Yasuyuki Shimura, Kazunori Umeo, Toshiro Takabatake, Takahiro Onimaru

  SciPost Phys. Proc. 11, 010 (2023) · published 5 June 2023 | Toggle abstract · pdf

  We report the electrical resistivity, specific heat, and magnetization measurements of Y$_{1-x}$Nd$_{x}$Co$_{2}$Zn$_{20}$ for $0.017 \leq x \leq 0.95$. The Schottky-type specific heat peak at around 13 K for all the samples is reproduced by the crystalline electric field model with the $\Gamma_{6}$ doublet ground state of a Nd$^{3+}$ ion. The magnetization and magnetic susceptibility data of the samples for $x \leq 0.06$ are well reproduced by the calculation without intersite magnetic interactions among Nd moments. Therefore, the dilute Nd system Y$_{1-x}$Nd$_{x}$Co$_{2}$Zn$_{20}$ for $x \leq 0.06$ is a good candidate to study on-site interaction of the $\Gamma_{6}$ doublet ground state of 4$f$ electrons with conduction electrons.

  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