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1. New metric improving Bayesian calibration of a multistage approach studying hadron and inclusive jet suppression

   https://doi.org/10.1103/PhysRevC.109.064903  

   Fan, W; Vujanovic, G; Bass, S A; Angerami, A; Arora, R; Cao, S; Chen, Y; Dai, T; Du, L; Ehlers, R; et al (June 2024, Physical Review C)

   We study parton energy-momentum exchange with the quark gluon plasma (QGP) within a multistage approach composed of in-medium Dokshitzer-Gribov-Lipatov-Altarelli-Parisi evolution at high virtuality, and (linearized) Boltzmann transport formalism at lower virtuality. This multistage simulation is then calibrated in comparison with high- $p_T$charged hadrons, $D$mesons, and the inclusive jet nuclear modification factors, using Bayesian model-to-data comparison, to extract the virtuality-dependent transverse momentum broadening transport coefficient $\hat{q}$. To facilitate this undertaking, we develop a quantitative metric for validating the Bayesian workflow, which is used to analyze the sensitivity of various model parameters to individual observables. The usefulness of this new metric in improving Bayesian model emulation is shown to be highly beneficial for future such analyses. Published by the American Physical Society2024 

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2. One-jettiness DIS event shape at ${\mathrm{N}}^3\mathrm{LL}+\mathcal{O}\left({\alpha }_s^2\right)$

   https://doi.org/10.1103/PhysRevD.110.014045  

   Cao, Haotian; Kang, Zhong-Bo; Liu, Xiaohui; Mantry, Sonny (July 2024, Physical Review D)

   We present results for the ${\tau }_1$and ${\tau }_{1a}$1-jettiness global event shape distributions, for deep inelastic scattering (DIS), at the ${\mathrm{N}}^3\mathrm{LL}+\mathcal{O}\left({\alpha }_s^2\right)$level of accuracy. These event-shape distributions quantify and characterize the pattern of final state radiation in electron-nucleus collisions. They can be used as a probe of nuclear structure functions, as nuclear medium effects in jet production, and for a precision extraction of the QCD strong coupling. The results presented here, along with the corresponding numerical codes, can be used for analyses with HERA data, in Electron-Ion Collider (EIC) simulation studies, and for eventual comparison with real EIC data. Published by the American Physical Society2024 

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3. Search for the nonresonant production of Higgs boson pairs via gluon fusion and vector-boson fusion in the $b\overline{b}{\tau }^{+}{\tau }^{-}$ final state in proton-proton collisions at $\sqrt{s}=13\mathrm{TeV}$ with the ATLAS detector

   https://doi.org/10.1103/PhysRevD.110.032012  

   Aad, G; Aakvaag, E; Abbott, B; Abeling, K; Abicht, N J; Abidi, S H; Aboelela, M; Aboulhorma, A; Abramowicz, H; Abreu, H; et al (August 2024, Physical Review D)

   A search for the nonresonant production of Higgs boson pairs in the $HH\to b\overline{b}{\tau }^{+}{\tau }^{-}$channel is performed using $140{\mathrm{fb}}^{-1}$of proton-proton collisions at a center-of-mass energy of 13 TeV recorded by the ATLAS detector at the CERN Large Hadron Collider. The analysis strategy is optimized to probe anomalous values of the Higgs boson self-coupling modifier ${\kappa }_{\lambda }$and of the quartic $HHVV$( $V=W,Z$) coupling modifier ${\kappa }_{2V}$. No significant excess above the expected background from Standard Model processes is observed. An observed (expected) upper limit ${\mu }_{HH}<5.9\left(3.3\right)$is set at 95% confidence-level on the Higgs boson pair production cross section normalized to its Standard Model prediction. The coupling modifiers are constrained to an observed (expected) 95% confidence interval of $-3.1<{\kappa }_{\lambda }<9.0$( $-2.5<{\kappa }_{\lambda }<9.3$) and $-0.5<{\kappa }_{2V}<2.7$( $-0.2<{\kappa }_{2V}<2.4$), assuming all other Higgs boson couplings are fixed to the Standard Model prediction. The results are also interpreted in the context of effective field theories via constraints on anomalous Higgs boson couplings and Higgs boson pair production cross sections assuming different kinematic benchmark scenarios. © 2024 CERN, for the ATLAS Collaboration2024CERN 

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4. Gapless superconductivity from low-frequency electrodynamic response of two-dimensional granular composites

   https://doi.org/10.1103/PhysRevResearch.7.013183  

   Zhang, Xinyang; Wu, Jinze; Palevski, Alexander; Kapitulnik, Aharon (February 2025, Physical Review Research)

   We measured the full complex ac conductance of two-dimensional granular $\mathrm{In}/{\mathrm{InO}}_x$composites using the mutual inductance technique to explore the transition from a “failed superconductor turned anomalous metal” to a robust superconductor. In this system, room-temperature annealing was adopted to tune the ${\mathrm{InO}}_x$-mediated coupling between In grains, allowing for the observation of both a “true” superconductor-to-insulator transition and the emergence of an intervening anomalous metallic state. In this paper, we show that further annealing increases the intergrain coupling, eliminating the anomalous metallic phase but at the same time preventing the emergence of strong Bose-dominated insulating phase. The complex ac conductance revealed a $T\to 0$finite dissipative response in a finite magnetic field, coexisting with a robust superfluid density. The anomalous power-law spectra for the dissipative response suggest quantum critical behavior as probed in the kilohertz range, and point to signatures of gapless superconductivity in our granular superconducting system. Published by the American Physical Society2025 

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5. Magnetic x-ray spectroscopy of Gd-doped EuO thin films

   https://doi.org/10.1103/PhysRevMaterials.9.024410  

   Arnold, E L; Riley, J M; Duffy, L B; Figueroa, A I; Held, R; Shen, K M; Schlom, D G; King, P_D C; Hoesch, M; van_der_Laan, G; et al (February 2025, Physical Review Materials)

   We present a detailed x-ray magnetic circular dichroism (XMCD) study of the magnetic properties of Gd-doped EuO thin films, synthesized via molecular-beam epitaxy with Gd doping levels up to over 12%. The impact of Gd doping on the electronic and magnetic behavior of EuO is studied using XMCD and magnetometry. Gd doping significantly enhances the Curie temperature ( $T_{\mathrm{C}}$) from 69 K in undoped EuO to over 120 K, driven by increased carrier density, while preserving the high quality of the single-crystalline films. At higher doping levels, a plateau in $T_{\mathrm{C}}$is observed, which is attributed to the formation of Eu-Gd nearest-neighbor pairs that limit dopant activation. We also observe a distinctive “double-dome” structure in the temperature-dependent magnetization, which we attribute to both the ferromagnetic ordering of Eu $4f$moments at lower temperatures and the influence of conduction electrons via $4f\text{−}5d$exchange interactions at higher temperatures. These findings provide key insights into the mechanisms of carrier-induced magnetic transitions. Published by the American Physical Society2025 

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