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1. Production of $\eta$ and ${\eta }^{\prime }$ mesons in $pp$ and $p\mathrm{Pb}$ collisions

   https://doi.org/10.1103/PhysRevC.109.024907  

   Aaij, R; Abdelmotteleb, A_S W; Abellan_Beteta, C; Abudinén, F; Ackernley, T; Adeva, B; Adinolfi, M; Adlarson, P; Agapopoulou, C; Aidala, C A; et al (February 2024, Physical Review C)

   The production of 𝜂 and 𝜂′ mesons is studied in proton-proton and proton-lead collisions collected with the LHCb detector. Proton-proton collisions are studied at center-of-mass energies of 5.02 and 13TeV and proton-lead collisions are studied at a center-of-mass energy per nucleon of 8.16TeV. The studies are performed in center-of-mass (c.m.) rapidity regions 2.5<𝑦c.m.<3.5 (forward rapidity) and −4.0<𝑦c.m.<−3.0 (backward rapidity) defined relative to the proton beam direction. The 𝜂 and 𝜂′ production cross sections are measured differentially as a function of transverse momentum for 1.5<𝑝T<10GeV and 3<𝑝T<10GeV, respectively. The differential cross sections are used to calculate nuclear modification factors. The nuclear modification factors for 𝜂 and 𝜂′ mesons agree at both forward and backward rapidity, showing no significant evidence of mass dependence. The differential cross sections of 𝜂 mesons are also used to calculate 𝜂/𝜋0 cross-section ratios, which show evidence of a deviation from the world average. These studies offer new constraints on mass-dependent nuclear effects in heavy-ion collisions, as well as 𝜂 and 𝜂′ meson fragmentation. 

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2. Nonlinear Arrhenius behavior of self-diffusion in $\beta \text{−}\mathrm{Ti}$ and $\mathrm{Mo}$

   https://doi.org/10.1103/PhysRevMaterials.6.063402  

   Wang, Yaxian; Chen, Zhangqi; Windl, Wolfgang; Zhao, Ji-Cheng (June 2022, Physical Review Materials)

   While anomalous diffusion coefficients with non-Arrhenius-like temperature dependence are observed in a number of metals, a conclusive comprehensive framework of explanation has not been brought forward to date. Here, we use first-principles calculations based on density functional theory to calculate self-diffusion coefficients in the bcc metals Mo and β-Ti by coupling quasiharmonic transition state theory and large-displacement phonon calculations and show that anharmonicity from thermal expansion is the major reason for the anomalous temperature dependence. We use a modified Debye approach to quantify the thermal expansion over the entire temperature range and introduce a method to relax the vacancy structure in a mechanically unstable crystal such as β-Ti. The effect of thermal expansion is found to be crucial for the nonlinear, non-Arrhenius “anomalous” self-diffusion in both bcc systems, with β-Ti showing a 60% larger relative nonlinearity parameter than Mo. Our results point to temperature dependence in the diffusion prefactor from thermal expansion as the major origin of anomalous self-diffusion. The methodology proposed for β-Ti is general and simple enough to be applicable to other mechanically unstable crystals. 

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3. Energy-Energy Correlator for Jet Production in $pp$ and $pA$ Collisions

   https://doi.org/10.1103/96xh-bd1w  

   Barata, João; Kang, Zhong-Bo; Mayo_López, Xoán; Penttala, Jani (June 2025, Physical Review Letters)

   In this Letter, we study the collinear limit of the energy-energy correlator in single-inclusive jet production in proton-proton and proton-nucleus collisions. We introduce a nonperturbative model that allows us to describe the energy-energy correlator in the entire angular region of the current experiments. Our results for proton-proton collisions show excellent agreement with CMS and ALICE data over a wide range of jet transverse momenta. For proton-nucleus collisions, we include modifications from the nuclear medium, and our predictions align well with the trends observed in recent ALICE measurements. 

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4. Measurement of $WWZ$ and $ZH$ Production Cross Sections at $\sqrt{s}=13$ and 13.6 TeV

   https://doi.org/10.1103/6z3d-zjw4  

   Hayrapetyan, A; Makarenko, V; Tumasyan, A; Adam, W; Andrejkovic, J W; Benato, L; Bergauer, T; Damanakis, K; Dragicevic, M; Giordano, C; et al (August 2025, Physical Review Letters)

   A measurement is presented of the cross section in proton-proton collisions for the production of two $W$bosons and one $Z$boson. It is based on data recorded by the CMS experiment at the CERN LHC at center-of-mass energies $\sqrt{s}=13$and 13.6 TeV, corresponding to an integrated luminosity of $200{\mathrm{fb}}^{-1}$. Events with four charged leptons (electrons or muons) in the final state are selected. Both nonresonant $WWZ$production and $ZH$production, with the Higgs boson decaying into two $W$bosons, are reported. For the first time, the two processes are measured separately in a simultaneous fit. Combining the two modes, signal strengths relative to the standard model (SM) predictions of ${0.75}_{-0.29}^{+0.34}$and ${1.74}_{-0.60}^{+0.71}$are measured for $\sqrt{s}=13$and 13.6 TeV, respectively. The observed (expected) significance for the triboson signal is 3.8 (2.5) standard deviations for $\sqrt{s}=13.6\mathrm{TeV}$, thus providing the first evidence for triboson production at this center-of-mass energy. Combining the two modes and the two center-of-mass energies, the inclusive signal strength relative to the SM prediction is measured to be ${1.03}_{-0.28}^{+0.31}$, with an observed (expected) significance of 4.5 (5.0) standard deviations. 

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5. Nuclear-modification factor of charged hadrons at forward and backward rapidity in $p$ $+$ $\mathrm{Al}$ and $p$ $+$ $\mathrm{Au}$ collisions at $\sqrt{s_{NN}}=200\mathrm{GeV}$

   https://doi.org/10.1103/PhysRevC.101.034910  

   Aidala, C.; Akiba, Y.; Alfred, M.; Andrieux, V.; Apadula, N.; Asano, H.; Azmoun, B.; Babintsev, V.; Bandara, N. S.; Barish, K. N.; et al (March 2020, Physical Review C)