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1. Determination of nuclear charge radius by extreme-ultraviolet spectroscopy of Na-like ions

   https://doi.org/10.1103/PhysRevResearch.7.L012024  

   Hosier, A; Dipti; Blundell, S A; Lapierre, A; Silwal, R; Gwinner, G; Tan, J N; Naing, A; Gillaspy, J D; Yang, Y; et al (February 2025, Physical Review Research)

   We report on a method for determining the absolute nuclear charge radius of high- $Z$elements using extreme-ultraviolet spectroscopy of highly charged Na-like ions in tandem with highly accurate atomic structure calculations of transition energy differences. The application of this method has reduced the nuclear charge radius uncertainty of ${}^{191}\mathrm{Ir}$by a factor of 8 from the currently accepted literature value, with a recently reported charge radius of 5.435(12) fm. The result reduces the charge radius uncertainty along the full Ir isotopic chain when combined with prior optical isotope shift measurements. The technique utilizes only a few million ions stored in an ion trap, which should apply to measurements with small quantities of radioactive nuclei. Published by the American Physical Society2025 

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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. 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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4. Evidence of Coherent Elastic Neutrino-Nucleus Scattering with COHERENT’s Germanium Array

   https://doi.org/10.1103/PhysRevLett.134.231801  

   Adamski, S; Ahn, M; Barbeau, P S; Belov, V; Bernardi, I; Bock, C; Bolozdynya, A; Bouabid, R; Browning, J; Cabrera-Palmer, B; et al (June 2025, Physical Review Letters)

   We report the first detection of coherent elastic neutrino-nucleus scattering (CEvNS) on natural germanium, measured at the Spallation Neutron Source at Oak Ridge National Laboratory. The Ge-Mini detector of the COHERENT collaboration employs large-mass, low-noise, high-purity germanium spectrometers, enabling excellent energy resolution, and an analysis threshold of 1.5 keV electron-equivalent ionization energy. We observe an on-beam excess of ${20.6}_{-6.3}^{+7.1}$counts with a total exposure of 10.22 GWhkg, and we reject the no-CEvNS hypothesis with $3.9\sigma$significance. The result agrees with the predicted standard model of particle physics signal rate within $2\sigma$. Published by the American Physical Society2025 

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5. Enantioselective One-Photon Excitation of Formic Acid

   https://doi.org/10.1103/PhysRevLett.133.093002  

   Tsitsonis, D; Trinter, F; Williams, J B; Fehre, K; Demekhin, Ph V; Jahnke, T; Dörner, R; Schöffler, M S (August 2024, Physical Review Letters)

   We use one-photon excitation to promote $K$-shell electrons of formic acid (which has a planar equilibrium structure) to an antibonding ${\pi }^{*}$orbital. The excited molecule is known to have a (chiral) pyramidal equilibrium structure. In our experiment, we determine the handedness of the excited molecule by imaging the momenta of charged fragments, which occur after its Coulomb explosion triggered by Auger-Meitner decay cascades succeeding the excitation. We find that the handedness of the excited molecule depends on its spatial orientation with respect to the propagation (or polarization) direction of the exciting photon. The effect is largely independent of the exact polarization properties of the light driving the $1s\to {\pi }^{*}$excitation. Published by the American Physical Society2024 

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