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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. 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)
3. Polarization observables $T$ and $F$ in the $\gamma p\to {\pi }^{0}p$ reaction at CLAS

   https://doi.org/10.1103/ml3y-pmb8  

   Jiang, H; Strauch, S; Strakovsky, I I; Rönchen, D; Workman, R; Achenbach, P; Alvarado, J S; Atac, H; Baashen, L; Baltzell, N A; et al (July 2026, Physical Review C)

   Pion photoproduction in the $\vec{\gamma }\vec{p}\to {\pi }^{0}p$reaction has been measured in the FROzen Spin Target (FROST) experiment at the Thomas Jefferson National Accelerator Facility. In this experiment, circularly polarized photons with energies up to 3.082 GeV impinged on a transversely polarized frozen-spin target. Final-state protons were detected in the Continuous Electron Beam Accelerator Facility (CEBAF) Large Acceptance Spectrometer. The polarization observables $T$and $F$have been extracted for $W$from 1445 to 2525 MeV, of which the energy range is much broader, and the precision is better than the existing measurements in higher $W$ranges. The data generally agree with predictions of present partial-wave analyses but also show marked differences for higher $W$ranges. By incorporating the present data into the databases, the Scattering Analysis Interactive Data (SAID) fits have been improved with relatively small ${\chi }^2$and significant changes in the parameters of the $\mathrm{\Delta }\left(1910\right)1/2^{+}$and $N\left(2190\right)7/2^{-}$have been found with the JüBo model. 

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4. $P$ -even and $P$ -odd asymmetries in ${}^{117}\mathrm{Sn}$ in the vicinity of the $p$ resonance at $E_p=1.33\mathrm{eV}$

   https://doi.org/10.1103/PhysRevC.109.014614  

   Charón-García, L E; Barrón-Palos, L; Curole, J; Snow, W M; Gudkov, V (January 2024, Physical Review C)
5. $ggh$ variations

   https://doi.org/10.1103/PhysRevD.105.076004  

   Martin, Adam; Trott, Michael (April 2022, Physical Review D)