Publications

Order by: publication date number of citations

• Differential measurements of jet sub-structure observables and their correlation in p+p collisions at √s = 200 GeV in STAR

  Monika Robotková

  SciPost Phys. Proc. 8, 071 (2022) · published 12 July 2022 | Toggle abstract · pdf

  This analysis extends recent measurements of the jet sub-structure observables based on the SoftDrop algorithm in p+p collisions at √s = 200 GeV in the STAR experiment. We present fully unfolded multi-differential measurements of jet sub-structure observables at the first split and their correlations for jets of different transverse momenta and radii. We compare our measurements to various Monte Carlo models.

• Light sterile neutrinos: a critical overview

  Ivan Esteban

  SciPost Phys. Proc. 1, 026 (2019) · published 20 February 2019 | Toggle abstract · pdf

  Light sterile neutrinos, first proposed after the results of the LSND experiment, have been a polemical topic for the last decades after seemingly contradictory data appeared from different experiments. In this overview, I review the experimental hints that point towards sterile neutrinos as well as their statistical compatibility. Even though the muon neutrino disappearance experiments strongly rule out vanilla sterile neutrinos, each oscillation channel remains internally mostly consistent. In any case, in the near future a series of independent and precise experiments should finally settle down this issue.

• Backward-Angle (u-Channel) Meson Production from JLab 12~GeV Hall C to EIC

  Wenliang B. Li

  SciPost Phys. Proc. 8, 036 (2022) · published 12 July 2022 | Toggle abstract · pdf

  The recent exclusive backward-angle electroproduction of omega from Jefferson Lab Hall C electron-proton fixed-target scattering experiments above the resonance region hints at a new domain of applicability of QCD factorization in a unique u-channel kinematics regime. Thanks to this effort, the interest in studying nucleon structure through u-channel meson production observables has grown significantly. In the fixed target configuration, theu-channel meson electroproduction observables feature a unique interaction picture: the target proton absorbs nearly all momentum induced by virtual photons and recoils forward, while the produced mesons (such as omega or pions) are left behind almost at rest near the target station. In this presentation, We provide a summary of the key observations of the existing u-channel meson production results, update-to-date theory insights, and a path to further exploration from JLab 12 GeV Hall C program to the future Electron-Ion Colliders

• Disorder in AdS$_3$/CFT$_2$

  Moritz Dorband, Daniel Grumiller, René Meyer, Suting Zhao

  SciPost Phys. 16, 017 (2024) · published 18 January 2024 | Toggle abstract · pdf

  We perturbatively study marginally relevant quenched disorder in AdS$_3$/CFT$_2$ to second order in the disorder strength. Using the Chern-Simons formulation of AdS$_3$ gravity for the Poincaré patch, we introduce disorder via the chemical potentials. We discuss the bulk and boundary properties resulting from the disorder-averaged metric. The disorder generates a small mass and angular momentum. In the bulk and the boundary, we find unphysical features due to the disorder average. Motivated by these features, we propose a Poincaré-Lindstedt-inspired resummation method. We discuss how this method enables us to remove all of the unphysical features and compare with other approaches to averaging.

• The role of atomic interactions in cavity-induced continuous time crystals

  Christian Høj Johansen, Johannes Lang, Francesco Piazza

  SciPost Phys. 17, 089 (2024) · published 24 September 2024 | Toggle abstract · pdf

  We consider continuous time-crystalline phases in dissipative many-body systems of atoms in cavities, focusing on the role of short-range interatomic interactions. First, we show that the latter can alter the nature of the time crystal by changing the type of the underlying critical bifurcation. Second, we characterize the heating mechanism and dynamics resulting from the short-range interactions and demonstrate that they make the time crystal inherently metastable. We argue this is generic for the broader class of dissipative time crystals in atom-cavity systems whenever the cavity loss rate is comparable to the atomic recoil energy. We observe that such a scenario for heating has several similarities to the one proposed for preheating in the early universe, where the oscillating coherent inflation field decays into a cascade of exponentially growing fluctuations. By extending approaches for dissipative dynamical systems to our many-body problem, we obtain analytical predictions for the parameters describing the phase transition and the heating rate inside the time-crystalline phase. We underpin and extend the analytical predictions of the heating rates with numerical simulations, which also show that the metastable regime exists when the inherent stochastic nature is taken into account.

• 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.

• Recent results from reactor antineutrino experiments

  Hyunkwan Seo

  SciPost Phys. Proc. 1, 027 (2019) · published 20 February 2019 | Toggle abstract · pdf

  The smallest neutrino mixing angle $\theta_{13}$ has been successfully measured by the disappearance of reactor antineutrinos at RENO, Daya Bay, and Double Chooz. The oscillation frequency is also measured based on energy and baseline dependent disappearance probability of reactor antineutrinos. Recent results fi nd a variation in the observed reactor antineutrino flux as a function of the reactor fuel evolution. We report more precisely measured values of $\theta_{13}$ and $\Delta m^2_{ee}$ and results on the evolution of observed reactor antineutrino yield and spectrum.

• Centrality dependence of multistrange baryon production in high-energy heavy-ion collisions

  Gevorg H. Arakelyan, Carlos Merino, Yuli M. Shabelski

  SciPost Phys. Proc. 15, 024 (2024) · published 3 April 2024 | Toggle abstract · pdf

  We consider the experimental data on the production of strange $\Lambda^{\prime}$s, and multistrange baryons ($\Xi$, $\Omega$), and antibaryons, on nuclear targets, at the energy region from SPS up to LHC, in the framework of the Quark-Gluon String Model. One remarkable result of this analysis is the significant dependence on the centrality of the collision of the experimental $\overline{\Xi}^+/\overline{\Lambda}$ and $\overline{\Omega}^+/\overline{\Lambda}$ ratios in heavy-ion collisions, at SPS energies.

• "The Greatest and Most Important Human Right": Citizenship and Bureaucratic Indifference in Refugee-UNHCR Correspondence

  Lamis Abdelaaty

  Mig. Pol. 3, 001 (2024) · published 8 April 2024 | Toggle abstract · pdf

  This article examines how refugees advocate for themselves with the UN Refugee Agency (UNHCR), and what responses their communications engender. It analyzes letters sent by refugees in Kenya to UNHCR headquarters in Geneva between 1983 and 1994. The findings underline a disjuncture between refugees’ efforts to constitute themselves as political agents, and UNHCR’s insistence on viewing them as depoliticized subjects. The refugees perform citizenship vis-à-vis UNHCR, using their shared identity as a basis for collective claims-making and trying to renegotiate their unequal relationship with the international organization. To empower themselves, they adopt the international organization’s own refugee rights vocabulary and play off different organizations and layers of UNHCR against each other. UNHCR’s responses (or lack thereof) demonstrate the consequences of its insulation and bureaucratization. These insights are especially noteworthy in light of recent progress on meaningful refugee participation in the refugee regime.

• Open strange meson $K^\pm_1$ in hot and dense nuclear matter

  Rajesh Kumar, Arvind Kumar

  SciPost Phys. Proc. 8, 055 (2022) · published 12 July 2022 | Toggle abstract · pdf

  Using the unification of the chiral SU(3) model and QCD sum rules, we deduce the in-medium properties of $K^\pm_1$ meson. Within the chiral SU(3) model, medium modified gluon and quark condensates are evaluated through their interactions with the scalar fields ($\sigma$, $\zeta$, $\delta$, and $\chi$). These condensates are further used as input in the Borel transformed equations of QCD sum rules to evaluate the in-medium mass of strange $K^\pm_1$ meson. The in-medium property of the above meson can be used to study the restoration of chiral symmetry in nuclear matter.