Publications

Order by: publication date number of citations

• Measurements of heavy-flavor production as a function of multiplicity with ALICE at the LHC

  Yoshini Bailung

  SciPost Phys. Proc. 10, 033 (2022) · published 11 August 2022 | Toggle abstract · pdf

  In this contribution, the production of heavy-flavor hadrons as a function of multiplicity, via the study of the D-meson and heavy-flavor hadron decay leptons self-normalized yields in pp collisions at the center of mass energy $\sqrt{s} = 13$ TeV is discussed. Comparisons are made with similar measurements of J/$\psi$ at $\sqrt{s} = 13$ TeV and various model calculations. The $\mathrm{\Lambda_{c}^{+}/D^{0}}$ and $\mathrm{D^{+}_{s}/D^{0}}$ yield ratios in different multiplicity intervals in pp collisions at $\sqrt{s} = 13$ TeV are also reported. In addition, the ALICE measurement of $\mathrm{\Lambda_{c}^{+}}$ production in p-Pb collisions at $\sqrt{s_{\rm{NN}}}$ = 5.02 TeV down to transverse momentum ($p_{\rm T}$) = 0 GeV/$c$ is presented. Finally, the nuclear modification factor is shown for open charm hadrons at $\sqrt{s} = 5.02$ TeV in p-Pb collisions. Finally, measurements of the elliptic flow of heavy-flavor hadron decay leptons in p-Pb systems are presented, which hint towards a possible collective behaviour in high multiplicity p-Pb collisions.

• Longitudinal double-spin asymmetries of inclusive jet and dijet production at STAR

  Maria Zurek

  SciPost Phys. Proc. 8, 086 (2022) · published 12 July 2022 | Toggle abstract · pdf

  At the STAR experiment, the gluon helicity distribution $\Delta g(x, Q^2)$ can be accessed through the double-spin asymmetries $A_{LL}$ of inclusive jet and dijet production in collisions of longitudinally polarized protons. These proceedings report on recently published results of $A_{LL}$ for inclusive jets and dijets at $\sqrt{s} = 200$~GeV and $\sqrt{s} = 510$ GeV in mid-pseudorapidity ($|\eta| < 1$) and preliminary results for dijets in intermediate pseudrapidity ($-0.8 < \eta < 1.8$). The mid-pseudorapidity jet and dijet measurements are sensitive to $\Delta g(x, Q^2)$ for gluon momentum fractions $x$ from $\simeq 0.5$ down to $\simeq 0.015$; the sensitivity region for dijets in intermediate pseudorapidity at 510 GeV extends to even lower $x$. The measurements are in good agreement with previous STAR results and recent theoretical evaluations of prior world data.

• Mergers as a probe of particle dark matter

  Anupam Ray

  SciPost Phys. Proc. 12, 056 (2023) · published 5 July 2023 | Toggle abstract · pdf

  Black holes below Chandrasekhar mass limit (1.4 $M_{\odot}$) can not be produced via any standard stellar evolution. Recently, gravitational wave experiments have also discovered unusually low mass black holes whose origin is yet to be known. We propose a simple yet novel formation mechanism of such low mass black holes. Non-annihilating particle dark matter, owing to their interaction with stellar nuclei, can gradually accumulate inside compact stars, and eventually swallows them to low mass black holes, ordinarily impermissible by the Chandrasekhar limit. We point out several avenues to test this proposal, concentrating on the cosmic evolution of the binary merger rates.

• Magnetic, electronic, and structural investigation of the strongly correlated Y$_{1-x}$Sm$_{x}$Co$_5$ system

  F. Passos, D. Cornejo, G. J. Nilsen, V. Martelli, J. Larrea Jiménez

  SciPost Phys. Proc. 11, 021 (2023) · published 6 June 2023 | Toggle abstract · pdf

  SmCo$_5$ and YCo$_5$ are isostructural compounds both showing large magnetocrystalline anisotropy, where the former originates mainly from the crystal-electric field and magnetic interactions. We investigate the contribution of both interactions by partially substituting Y by Sm in as-cast polycrystalline Y$_{1-x}$Sm$_{x}$Co$_5$ (with $x$=0.00, 0.12, 0.18, 0.31, and 0.40) and measuring their structural, magnetic, and electrical properties through X-ray diffraction, magnetization, and electrical transport measurements. Our results suggest an interplay between microstructure strain in as-cast samples and the electronic and magnetic interactions.

• Measurements and searches of Higgs boson production involving fermion couplings with the ATLAS detector

  Shigeki Hirose

  SciPost Phys. Proc. 8, 006 (2022) · published 11 July 2022 | Toggle abstract · pdf

  In the standard model, fermions acquire the mass via the Yukawa interaction. This mechanism can be tested by measuring couplings of the fermions with the Higgs boson. At the ATLAS experiment, the Higgs-fermion coupling measurements became possible thanks to the abundant dataset: the integrated luminosity of 139~fb$^{-1}$ at the centre-of-mass energy of 13~TeV as well as 25~fb$^{-1}$ at 7--8~TeV. This paper presents recent results from measurements of the Higgs boson productions in decays to a fermion pair in the final state with the ATLAS detector.

• The Higgs mechanism with diagrams: A didactic approach

  Jochem Kip, Ronald Kleiss

  SciPost Phys. Lect. Notes 88 (2024) · published 14 October 2024 | Toggle abstract · pdf

  We present a paedagogical treatment of the electroweak Higgs mechanism based solely on Feynman diagrams and S-matrix elements, without recourse to (gauge) symmetry arguments. Throughout, the emphasis is on Feynman rules and the Schwinger-Dyson equations; it is pointed out that particular care is needed in the treatment of tadpole diagrams and their symmetry factors.

• Photon counting statistics in Gaussian bosonic networks

  Kalle Sulo Ukko Kansanen, Pedro Portugal, Christian Flindt, Peter Samuelsson

  SciPost Phys. 18, 116 (2025) · published 1 April 2025 | Toggle abstract · pdf

  The statistics of transmitted photons in microwave cavities play a foundational role in microwave quantum optics and its technological applications. By utilizing quantum mechanical phase-space methods, we here develop a general theory of the photon counting statistics in Gaussian bosonic networks consisting of driven cavities with beamsplitter interactions and two-mode-squeezing. The dynamics of the network can be captured by a Lyapunov equation for the covariance matrix of the cavity fields, which generalizes to a Riccati equation, when counting fields are included. By solving the Riccati equation, we obtain the statistics of emitted and absorbed photons as well as the time-dependent correlations encoded in waiting time distributions and second-order coherence functions. To illustrate our theoretical framework, we first apply it to a simple linear network consisting of two coupled cavities, for which we evaluate the photon cross-correlations and discuss connections between the photon emission statistics and the entanglement between the cavities. We then consider a bosonic circulator consisting of three coupled cavities, for which we investigate how a synthetic flux may affect the direction of the photon flow, similarly to recent experiments. Our general framework paves the way for systematic investigations of the photon counting statistics in Gaussian bosonic networks.

• Complementarity of Lepton-Charge and Forward-Backward Drell-Yan Asymmetries for Precision Electroweak Measurements and Quark Density Determinations

  J. Fiaschi, F. Giuli, F. Hautmann, S. Moretti

  SciPost Phys. Proc. 8, 038 (2022) · published 12 July 2022 | Toggle abstract · pdf

  We address the impact of future measurements of charged and neutral current Drell-Yan (DY) asymmetries and their combination on Parton Distribution Functions (PDFs) uncertainties. We quantify the reduction of PDF uncertainties using the QCD tool xFitter. We examine the effects of such reduced PDF errors on both Standard Model (SM) and Beyond SM (BSM) observables.

• The diagrammatic coaction and cuts of the double box

  Einan Gardi, Aris Ioannou

  SciPost Phys. Proc. 7, 012 (2022) · published 20 June 2022 | Toggle abstract · pdf

  The diagrammatic coaction encodes the analytic structure of Feynman integrals by mapping any given Feynman diagram into a tensor product of diagrams defined by contractions and cuts of the original diagram. Feynman integrals evaluate to generalized hypergeometric functions in dimensional regularization. Establishing the coaction on this type of functions has helped formulating and checking the diagrammatic coaction of certain two-loop integrals. In this talk we study its application on the fully massless double box diagram. We make use of differential equation techniques, which, together with the properties of homology and cohomology theory of the resulting hypergeometric functions, allow us to formulate the coaction on a range of cuts of the double box in closed form.

• Exclusion process subject to conformational size changes

  Yvan Rousset, Luca Ciandrini, Norbert Kern

  SciPost Phys. 6, 077 (2019) · published 26 June 2019 | Toggle abstract · pdf

  We introduce a model for stochastic transport on a one-dimensional substrate with particles assuming different conformations during their stepping cycles. These conformations correspond to different footprints on the substrate: in order to advance, particles are subject to successive contraction and expansion steps with different characteristic rates. We thus extend the paradigmatic exclusion process, provide predictions for all regimes of these rates that are in excellent agreement with simulations, and show that the current-density relation may be affected considerably. Symmetries are discussed, and exploited. We discuss our results in the context of molecular motors, confronting a hand-over-hand and an inchworm stepping mechanism, as well as for ribosomes.