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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. ${\mathrm{\Lambda }}_c^{+}$ production in $pp$ and in $p$ -Pb collisions at $\sqrt{s_{NN}}=5.02$ TeV

   https://doi.org/10.1103/PhysRevC.104.054905  

   Acharya, S.; Adamová, D.; Adler, A.; Adolfsson, J.; Aglieri Rinella, G.; Agnello, M.; Agrawal, N.; Ahammed, Z.; Ahmad, S.; Ahn, S. U.; et al (November 2021, Physical Review C)
3. $\varphi$ meson production in $p+\mathrm{Al},$ $p+\mathrm{Au},$ $d+\mathrm{Au},$ and ${}^3\mathrm{He}+\mathrm{Au}$ collisions at $\sqrt{s_{NN}}=200\mathrm{GeV}$

   https://doi.org/10.1103/PhysRevC.106.014908  

   Acharya, U.; Adare, A.; Aidala, C.; Ajitanand, N. N.; Akiba, Y.; Alfred, M.; Andrieux, V.; Apadula, N.; Asano, H.; Azmoun, B.; et al (July 2022, Physical Review C)
4. Measurement of $\omega$ meson production in $pp$ and $p$ -Pb collisions at $\sqrt{s_{NN}}=5.02$ TeV

   https://doi.org/10.1103/ls6w-x1bb  

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

   We present the measurement of the $p_{\mathrm{T}}$-differential production cross section of $\omega$mesons in and $p$-Pb collisions at $\sqrt{s_{NN}}=5.02$TeV at midrapidity by ALICE. In addition, the first measurement of the nuclear modification factor $R_{p\mathrm{Pb}}$for $\omega$mesons at LHC energies is presented, complementing the existing measurements of lighter neutral mesons such as the ${\pi }^0$and $\eta$. Within the measured $p_{\mathrm{T}}$range, the $R_{p\mathrm{Pb}}$of $\omega$mesons is compatible with no cold nuclear matter effects within the uncertainties, consistent with previous measurements at lower energies. The $\omega /{\pi }^0$ratio is presented for both collision systems, showing no collision system dependence within the uncertainties. The comparison to previously published $\omega /{\pi }^0$ratios at lower and higher collision energies in collisions suggests a decreasing trend of the ratio above $p_{\mathrm{T}}$= 4 GeV/ $c$with increasing collision energy. The data in both collision systems are compared to predictions from PYTHIA 8, EPOS LHC, and DPMJET event generators, revealing significant shortcomings in these models’ ability to describe the production of $\omega$mesons. 

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5. Hard-photon-triggered jets in $p\text{−}p$ and $A\text{−}A$ collisions

   https://doi.org/10.1103/yyr5-zp16  

   Sirimanna, C; Tachibana, Y; Majumder, A; Angerami, A; Arora, R; Bass, S A; Chen, Y; Datta, R; Du, L; Ehlers, R; et al (June 2025, Physical Review C)

   An investigation of high-transverse-momentum (high- $p_T$) photon-triggered jets in proton-proton ( $p\text{−}p$) and ion-ion ( $A\text{−}A$) collisions at $\sqrt{s_{NN}}=0.2$and $5.02\mathrm{TeV}$is carried out, using the multistage description of in-medium jet evolution. Monte Carlo simulations of hard scattering and energy loss in heavy-ion collisions are performed using parameters tuned in a previous study of the nuclear modification factor ( $R_{AA}$) for inclusive jets and high- $p_T$hadrons. We obtain a good reproduction of the experimental data for photon-triggered jet $R_{AA}$, as measured by the ATLAS detector, the distribution of the ratio of jet to photon $p_T$( $X_{J\gamma }$), measured by both CMS and ATLAS, and the photon-jet azimuthal correlation as measured by CMS. We obtain a moderate description of the photon-triggered jet $I_{AA}$, as measured by STAR. A noticeable improvement in the comparison is observed when one goes beyond prompt photons and includes bremsstrahlung and decay photons, revealing their significance in certain kinematic regions, particularly at $X_{J\gamma }>1$. Moreover, azimuthal angle correlations demonstrate a notable impact of bremsstrahlung photons on the distribution, emphasizing their role in accurately describing experimental results. This work highlights the success of the multistage model of jet modification to straightforwardly predict (this set of) photon-triggered jet observables. This comparison, along with the role played by bremsstrahlung photons, has important consequences on the inclusion of such observables in a future Bayesian analysis. Published by the American Physical Society2025 

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