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1. Spectroscopic Confirmation of an Ultra-Massive Galaxy in a Protocluster at $z\sim 4.9$

   https://doi.org/10.33232/001c.120087  

   Urbano_Stawinski, Stephanie M; Cooper, M C; Forrest, Ben; Muzzin, Adam; Marchesini, Danilo; Wilson, Gillian; Gomez, Percy; McConachie, Ian; Marsan, Z Cemile; Annuziatella, Marianna; et al (June 2024, The Open Journal of Astrophysics)

   We present spectroscopic confirmation of an ultra-massive galaxy (UMG) with $log\left(M_{\star }/M_{\odot }\right)=10.98\pm 0.07$at $z_{\mathrm{s}\mathrm{p}\mathrm{e}\mathrm{c}}=4.8947$in the Extended Groth Strip (EGS), based on deep observations of Ly $\alpha$emission with Keck/DEIMOS. The ultra-massive galaxy (UMG-28740) is the most massive member in one of the most significant overdensities in the EGS, with four additional photometric members with $log\left(M_{\star }/M_{\odot }\right)>10.5$within $R_{\mathrm{p}\mathrm{r}\mathrm{o}\mathrm{j}}\sim 1$cMpc. Spectral energy distribution (SED) fitting using a large suite of star formation histories and two sets of high-quality photometry from ground- and space-based facilities consistently estimates the mass of this object to be $log\left(M_{\star }/M_{\odot }\right)\sim 11$with a small standard deviation between measurements ( $\sigma =0.07$). While the best-fit SED models agree on stellar mass, we find discrepancies in the estimated star formation rate for UMG-28740, resulting in either a star-forming or quiescent system. $𝐽𝑊𝑆𝑇$/NIRCam photometry of UMG-28740 strongly favors a quiescent scenario, demonstrating the need for high-quality mid-IR observations. Assuming the galaxy to be quiescent, UMG-28740 formed the bulk of its stars at $z>10$and is quenching at $z\sim 8$, resulting in a high star formation efficiency at high redshift ( $ϵ\sim 0.2$at $z\sim 5$and $ϵ\gtrsim 1$at $z\gtrsim 8$). As the most massive galaxy in its protocluster environment, UMG-28740 is a unique example of the impossibly early galaxy problem. 

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2. 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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3. Dark Energy Survey Year 3 results: Constraints on extensions to $\mathrm{\Lambda }\mathrm{CDM}$ with weak lensing and galaxy clustering

   https://doi.org/10.1103/PhysRevD.107.083504  

   Abbott, T. M. C.; Aguena, M.; Alarcon, A.; Alves, O.; Amon, A.; Andrade-Oliveira, F.; Annis, J.; Avila, S.; Bacon, D.; Baxter, E.; et al (April 2023, Physical Review D)
4. 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)
5. $P$ -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.; NOPTREX_Collaboration (January 2024, Physical Review C)