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1. Search for Highly Ionizing Particles in $pp$ Collisions during LHC Run 2 Using the Full MoEDAL Detector

   https://doi.org/10.1103/PhysRevLett.134.071802  

   Acharya, B; Alexandre, J; Benes, P; Bergmann, B; Bertolucci, S; Bevan, A; Brancaccio, R; Branzas, H; Burian, P; Campbell, M; et al (February 2025, Physical Review Letters)

   This search for magnetic monopoles (MMs) and high electric charge objects (HECOs) with spins 0, $1/2$, and 1, uses for the first time the full MoEDAL detector, exposed to $6.46{\mathrm{fb}}^{-1}$proton-proton collisions at 13 TeV. The results are interpreted in terms of Drell-Yan and photon-fusion pair production. Mass limits on direct production of MMs of up to 10 Dirac magnetic charges and HECOs with electric charge in the range $10e$to $400e$, were achieved. The charge limits placed on MM and HECO production are currently the strongest in the world. MoEDAL is the only LHC experiment capable of being directly calibrated for highly ionizing particles using heavy ions and with a detector system dedicated to definitively measuring magnetic charge. Published by the American Physical Society2025 

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2. Probing Strangeness Hadronization with Event-by-Event Production of Multistrange Hadrons

   https://doi.org/10.1103/PhysRevLett.134.022303  

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

   This Letter presents the first measurement of event-by-event fluctuations of the net number (difference between the particle and antiparticle multiplicities) of multistrange hadrons ${\mathrm{\Xi }}^{-}$and ${\overline{\mathrm{\Xi }}}^{+}$and its correlation with the net-kaon number using the data collected by the ALICE Collaboration in pp, p-Pb, and Pb-Pb collisions at a center-of-mass energy per nucleon pair $\sqrt{s_{\mathrm{NN}}}=5.02\mathrm{TeV}$. The statistical hadronization model with a correlation over three units of rapidity between hadrons having the same and opposite strangeness content successfully describes the results. On the other hand, string-fragmentation models that mainly correlate strange hadrons with opposite strange quark content over a small rapidity range fail to describe the data. © 2025 CERN, for the ALICE Collaboration2025CERN 

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3. Search for prompt production of pentaquarks in charm hadron final states

   https://doi.org/10.1103/PhysRevD.110.032001  

   Aaij, R; Abdelmotteleb, A_S W; Abellan_Beteta, C; Abudinén, F; Ackernley, T; Adeva, B; Adinolfi, M; Adlarson, P; Afsharnia, H; Agapopoulou, C; et al (August 2024, Physical Review D)

   A search for hidden-charm pentaquark states decaying to a range of ${\mathrm{\Sigma }}_c\overline{D}$and ${\mathrm{\Lambda }}_c^{+}\overline{D}$final states, as well as doubly charmed pentaquark states to ${\mathrm{\Sigma }}_{c}D$and ${\mathrm{\Lambda }}_c^{+}D$, is made using samples of proton-proton collision data corresponding to an integrated luminosity of $5.7{\mathrm{fb}}^{-1}$recorded by the LHCb detector at $\sqrt{s}=13\mathrm{TeV}$. Since no significant signals are found, upper limits are set on the pentaquark yields relative to that of the ${\mathrm{\Lambda }}_c^{+}$baryon in the ${\mathrm{\Lambda }}_c^{+}\to p{K}^{-}{\pi }^{+}$decay mode. The known pentaquark states are also investigated, and their signal yields are found to be consistent with zero in all cases. © 2024 CERN, for the LHCb Collaboration2024CERN 

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4. Search for the baryon number and lepton number violating decays ${\tau }^{-}\to \mathrm{\Lambda }{\pi }^{-}$ and ${\tau }^{-}\to \overline{\mathrm{\Lambda }}{\pi }^{-}$ at Belle II

   https://doi.org/10.1103/PhysRevD.110.112003  

   Adachi, I; Aggarwal, L; Ahmed, H; Aihara, H; Akopov, N; Aloisio, A; Althubiti, N; Anh_Ky, N; Asner, D M; Atmacan, H; et al (December 2024, Physical Review D)

   We present a search for the baryon number $B$and lepton number $L$violating decays ${\tau }^{-}\to \mathrm{\Lambda }{\pi }^{-}$and ${\tau }^{-}\to \overline{\mathrm{\Lambda }}{\pi }^{-}$produced from the $e^{+}{e}^{-}\to {\tau }^{+}{\tau }^{-}$process, using a $364{\mathrm{fb}}^{-1}$data sample collected by the Belle II experiment at the SuperKEKB collider. No evidence of signal is found in either decay mode, which have $\left|\mathrm{\Delta }\right(B-L\left)\right|$equal to 2 and 0, respectively. Upper limits at 90% credibility level on the branching fractions of ${\tau }^{-}\to \mathrm{\Lambda }{\pi }^{-}$and ${\tau }^{-}\to \overline{\mathrm{\Lambda }}{\pi }^{-}$are determined to be $4.7\times {10}^{-8}$and $4.3\times {10}^{-8}$, respectively. Published by the American Physical Society2024 

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5. Observation of Medium-Induced Yield Enhancement and Acoplanarity Broadening of Low- $p_{\mathrm{T}}$ Jets from Measurements in $pp$ and Central Pb-Pb Collisions at $\sqrt{s_{\mathrm{NN}}}=5.02\mathrm{TeV}$

   https://doi.org/10.1103/PhysRevLett.133.022301  

   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 Letters)

   The ALICE Collaboration reports the measurement of semi-inclusive distributions of charged-particle jets recoiling from a high transverse momentum (high $p_{\mathrm{T}}$) hadron trigger in proton-proton and central Pb-Pb collisions at $\sqrt{s_{\mathrm{NN}}}=5.02\mathrm{TeV}$. A data-driven statistical method is used to mitigate the large uncorrelated background in central Pb-Pb collisions. Recoil jet distributions are reported for jet resolution parameter $R=0.2$, 0.4, and 0.5 in the range $7<p_{\mathrm{T},\text{jet}}<140\mathrm{GeV}/c$and trigger-recoil jet azimuthal separation $\pi /2<\mathrm{\Delta }\phi <\pi$. The measurements exhibit a marked medium-induced jet yield enhancement at low $p_{\mathrm{T}}$and at large azimuthal deviation from $\mathrm{\Delta }\phi \sim \pi$. The enhancement is characterized by its dependence on $\mathrm{\Delta }\phi$, which has a slope that differs from zero by $4.7\sigma$. Comparisons to model calculations incorporating different formulations of jet quenching are reported. These comparisons indicate that the observed yield enhancement arises from the response of the QGP medium to jet propagation. © 2024 CERN, for the ALICE Collaboration2024CERN 

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