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1. Search for Quasiparticle Scattering in the Quark-Gluon Plasma with Jet Splittings in $pp$ and Pb-Pb Collisions at $\sqrt{s_{\mathrm{NN}}}=5.02\mathrm{TeV}$

   https://doi.org/10.1103/PhysRevLett.135.031901  

   Acharya, S; Agarwal, A; Aglieri_Rinella, G; Aglietta, L; Agnello, M; Agrawal, N; Ahammed, Z; Ahmad, S; Ahn, S U; Ahuja, I; et al (July 2025, Physical Review Letters)

   The ALICE Collaboration reports measurements of the large relative transverse momentum ( $k_T$) component of jet substructure in $pp$and Pb-Pb collisions at center-of-mass energy per nucleon pair $\sqrt{s_{\mathrm{NN}}}=5.02\mathrm{TeV}$. Enhancement in the yield of such large- $k_{\mathrm{T}}$emissions in head-on Pb-Pb collisions is predicted to arise from partonic scattering with quasiparticles of the quark-gluon plasma. The analysis utilizes charged-particle jets reconstructed by the anti- $k_{\mathrm{T}}$algorithm with resolution parameter $R=0.2$in the transverse-momentum interval $60<p_{\mathrm{T},\mathrm{ch},\mathrm{jet}}<80\mathrm{GeV}/c$. The soft drop and dynamical grooming algorithms are used to identify high transverse momentum splittings in the jet shower. Comparison of measurements in Pb-Pb and $pp$collisions shows medium-induced narrowing, corresponding to yield suppression of high- $k_T$splittings, in contrast to the expectation of yield enhancement due to quasiparticle scattering. The measurements are compared to theoretical model calculations incorporating jet modification due to jet-medium interactions (“jet quenching”), both with and without quasiparticle scattering effects. These measurements provide new insight into the underlying mechanisms and theoretical modeling of jet quenching. 

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2. High-statistics measurement of antineutrino quasielasticlike scattering at $E_{\overline{\nu }}$ 6 GeV on a hydrocarbon target

   https://doi.org/10.1103/PhysRevD.108.032018  

   Bashyal, A; Akhter, S; Ahmad_Dar, Z; Akbar, F; Ansari, V; Ascencio, M V; Sajjad_Athar, M; Bercellie, A; Betancourt, M; Bodek, A; et al (August 2023, Physical Review D)

   We present measurements of the cross section for antineutrino charged-current quasielasticlike scattering on hydrocarbon using the medium energy NuMI wide-band neutrino beam peaking at antineutrino energy hE¯νi ∼ 6 GeV. The measurements are presented as a function of the longitudinal momentum (pjj) and transverse momentum (pT) of the final state muon. This work complements our previously reported high statistics measurement in the neutrino channel and extends the previous antineutrino measurement made in a low energy beam at hE¯νi ∼ 3.5 GeV out to pT of 2.5 GeV=c. Current theoretical models do not completely describe the data in this previously unexplored high pT region. The single differential cross section as a function of four-momentum transfer (Q2 QE) now extends to 4 GeV2 with high statistics. The cross section as a function of Q2 QE shows that the tuned simulations developed by the MINERvA Collaboration that agreed well with the low energy beam measurements do not agree as well with the medium energy beam measurements. Newer neutrino interaction models such as the GENIE v3 tunes are better able to simulate the high Q2 QE region. 

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3. Measurements of jet quenching using semi-inclusive hadron+jet distributions in $pp$ and central Pb-Pb collisions at $\sqrt{s_{NN}}=5.02$ TeV

   https://doi.org/10.1103/PhysRevC.110.014906  

   Acharya, S; Adamová, D; Aglieri_Rinella, G; Agnello, M; Agrawal, N; Ahammed, Z; Ahmad, S; Ahn, S U; Ahuja, I; Akindinov, A; et al (July 2024, Physical Review C)

   The ALICE Collaboration reports measurements of the semi-inclusive distribution of charged-particle jets recoiling from a high transverse momentum (high $p_{\mathrm{T}}$) charged hadron, in $pp$and central Pb-Pb collisions at center-of-mass energy per nucleon–nucleon collision $\sqrt{s_{\mathrm{NN}}}=5.02$TeV. The large uncorrelated background in central Pb-Pb collisions is corrected using a data-driven statistical approach which enables precise measurement of recoil jet distributions over a broad range in $p_{\mathrm{T},\mathrm{ch}\mathrm{jet}}$and jet resolution parameter $R$. Recoil jet yields are reported for $R=0.2$, 0.4, and 0.5 in the range $7<p_{\mathrm{T},\mathrm{ch}\mathrm{jet}}<140 \mathrm{GeV}/c$and $\pi /2<\mathrm{\Delta }\phi <\pi$, where $\mathrm{\Delta }\phi$is the azimuthal angular separation between hadron trigger and recoil jet. The low- $p_{\mathrm{T},\mathrm{ch}\mathrm{jet}}$reach of the measurement explores unique phase space for studying jet quenching, the interaction of jets with the quark–gluon plasma generated in high-energy nuclear collisions. Comparison of $p_{\mathrm{T},\mathrm{ch}\mathrm{jet}}$distributions from $pp$and central Pb-Pb collisions probes medium-induced jet energy loss and intra-jet broadening, while comparison of their acoplanarity distributions explores in-medium jet scattering and medium response. The measurements are compared to theoretical calculations incorporating jet quenching. ©2024 CERN, for the ALICE Collaboration2024CERN 

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4. Measurement of $d^2\sigma /d\left|\overrightarrow{q}\right|d{E}_{\text{avail}}$ in charged current ${\nu }_{\mu }$ -nucleus interactions at $⟨E_{\nu }⟩=1.86\mathrm{GeV}$ using the NOvA Near Detector

   https://doi.org/10.1103/PhysRevD.111.052009  

   Acero, M A; Acharya, B; Adamson, P; Aliaga, L; Anfimov, N; Antoshkin, A; Arrieta-Diaz, E; Asquith, L; Aurisano, A; Back, A; et al (March 2025, Physical Review D)

   Double- and single-differential cross sections for inclusive charged-current ${\nu }_{\mu }$-nucleus scattering are reported for the kinematic domain 0 to $2\mathrm{GeV}/c$in three-momentum transfer and 0 to 2 GeV in available energy, at a mean ${\nu }_{\mu }$energy of 1.86 GeV. The measurements are based on an estimated 995,760 ${\nu }_{\mu }$charged-current (CC) interactions in the scintillator medium of the NOvA Near Detector. The subdomain populated by 2-particle-2-hole (2p2h) reactions is identified by the cross section excess relative to predictions for ${\nu }_{\mu }$-nucleus scattering that are constrained by a data control sample. Models for 2-particle-2-hole processes are rated by ${\chi }^2$comparisons of the predicted-versus-measured ${\nu }_{\mu }$CC inclusive cross section over the full phase space and in the restricted subdomain. Shortfalls are observed in neutrino generator predictions obtained using the theory-based València and SuSAv2 2p2h models. Published by the American Physical Society2025 

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5. Search for inelastic dark matter-nucleus scattering with the PICO-60 ${\mathrm{CF}}_3\mathrm{I}$ and ${\mathrm{C}}_3{\mathrm{F}}_8$ bubble chambers

   https://doi.org/10.1103/PhysRevD.108.062003  

   Adams, E; Ali, B; Arnquist, I J; Baxter, D; Behnke, E; Bressler, M; Broerman, B; Chen, C J; Clark, K; Collar, J I; et al (September 2023, Physical Review D)

   PICO bubble chambers have exceptional sensitivity to inelastic dark matter-nucleus interactions due to a combination of their extended nuclear recoil energy detection window from a few keV to O(100 keV) or more and the use of iodine as a heavy target. Inelastic dark matter-nucleus scattering is interesting for studying the properties of dark matter, where many theoretical scenarios have been developed. This study reports the results of a search for dark matter inelastic scattering with the PICO-60 bubble chambers. The analysis reported here comprises physics runs from PICO-60 bubble chambers using CF3I and C3F8. The CF3I run consisted of 36.8 kg of CF3I reaching an exposure of 3415 kg-day operating at thermodynamic thresholds between 7 and 20 keV. The C3F8 runs consisted of 52 kg of C3F8 reaching exposures of 1404 kg-day and 1167 kg-day running at thermodynamic thresholds of 2.45 keV and 3.29 keV, respectively. The analysis disfavors various scenarios, in a wide region of parameter space, that provide a feasible explanation of the signal observed by DAMA, assuming an inelastic interaction, considering that the PICO CF3I bubble chamber used iodine as the target material. 

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