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1. Anisotropic flow of identified hadrons in Xe-Xe collisions at $$ \sqrt{s_{\mathrm{NN}}} $$ = 5.44 TeV

   https://doi.org/10.1007/JHEP10(2021)152  

   Acharya, S.; Adamová, D.; Adler, A.; Aglieri Rinella, G.; Agnello, M.; Agrawal, N.; Ahammed, Z.; Ahmad, S.; Ahn, S. U.; Ahuja, I.; et al (October 2021, Journal of High Energy Physics)

   A bstract Measurements of elliptic ( v 2 ) and triangular ( v 3 ) flow coefficients of π ± , K ± , p+ $$ \overline{\mathrm{p}} $$ p ¯ , $$ {\mathrm{K}}_{\mathrm{S}}^0 $$ K S 0 , and Λ+ $$ \overline{\Lambda} $$ Λ ¯ obtained with the scalar product method in Xe-Xe collisions at $$ \sqrt{s_{\mathrm{NN}}} $$ s NN = 5 . 44 TeV are presented. The results are obtained in the rapidity range | y | < 0 . 5 and reported as a function of transverse momentum, p T , for several collision centrality classes. The flow coefficients exhibit a particle mass dependence for p T < 3 GeV/ c , while a grouping according to particle type (i.e., meson and baryon) is found at intermediate transverse momenta (3 < p T < 8 GeV/ c ). The magnitude of the baryon v 2 is larger than that of mesons up to p T = 6 GeV/ c . The centrality dependence of the shape evolution of the p T -differential v 2 is studied for the various hadron species. The v 2 coefficients of π ± , K ± , and p+ $$ \overline{\mathrm{p}} $$ p ¯ are reproduced by MUSIC hydrodynamic calculations coupled to a hadronic cascade model (UrQMD) for p T < 1 GeV/ c . A comparison with v n measurements in the corresponding centrality intervals in Pb-Pb collisions at $$ \sqrt{s_{\mathrm{NN}}} $$ s NN = 5 . 02 TeV yields an enhanced v 2 in central collisions and diminished value in semicentral collisions. 

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2. Polarization tensor of magnetized quark-gluon plasma at nonzero baryon density

   https://doi.org/10.1140/epjc/s10052-021-09650-3  

   Wang, Xinyang; Shovkovy, Igor (October 2021, The European Physical Journal C)

   Abstract We derive a general expression for the absorptive part of the one-loop photon polarization tensor in a strongly magnetized quark-gluon plasma at nonzero baryon chemical potential. To demonstrate the application of the main result in the context of heavy-ion collisions, we study the effect of a nonzero baryon chemical potential on the photon emission rate. The rate and the ellipticity of photon emission are studied numerically as a function the transverse momentum (energy) for several values of temperature and chemical potential. When the chemical potential is small compared to the temperature, the rates of the quark and antiquark splitting processes (i.e.,$$q\rightarrow q +\gamma $$ $q\to q+\gamma$and$${\bar{q}}\rightarrow {\bar{q}} +\gamma $$ $\overline{q}\to \overline{q}+\gamma$, respectively) are approximately the same. However, the quark splitting gradually becomes the dominant process with increasing the chemical potential. We also find that increasing the chemical potential leads to a growing total photon production rate but has only a small effect on the ellipticity of photon emission. The quark-antiquark annihilation ($$q+{\bar{q}}\rightarrow \gamma $$ $q+\overline{q}\to \gamma$) also contributes to the photon production, but its contribution remains relatively small for a wide range of temperatures and chemical potentials investigated. 

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3. Kato square root problem with unbounded leading coefficients

   https://doi.org/https://doi.org/10.1090/proc/14224  

   Escauriaza, L.; Hofmann, S. (October 2018, Proceedings of the American Mathematical Society)

   We prove the Kato conjecture for elliptic operators, $$L=-\nabla\cdot\left((\mathbf A+\mathbf D)\nabla\ \right)$$, with $$\mathbf A$$ a complex measurable bounded coercive matrix and $$\mathbf D$$ a measurable real-valued skew-symmetric matrix in $$\re^n$$ with entries in $$BMO(\re^n)$$;\, i.e., the domain of $$\sqrt{L}\,$$ is the Sobolev space $$\dot H^1(\re^n)$$, with the estimate $$\|\sqrt{L}\, f\|_2 \lesssim \| \nabla f\|_2\,.$$ 

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4. Energy-scaling behavior of intrinsic transverse-momentum parameters in Drell-Yan simulation

   https://doi.org/10.1103/PhysRevD.111.072003  

   Hayrapetyan, A; Tumasyan, A; Adam, W; Andrejkovic, J W; Bergauer, T; Chatterjee, S; Damanakis, K; Dragicevic, M; Hussain, P S; Jeitler, M; et al (April 2025, Physical Review D)

   An analysis is presented based on models of the intrinsic transverse momentum (intrinsic $k_{\mathrm{T}}$) of partons in nucleons by studying the dilepton transverse momentum in Drell-Yan events. Using parameter tuning in event generators and existing data from fixed-target experiments and from hadron colliders, our investigation spans 3 orders of magnitude in center-of-mass energy and 2 orders of magnitude in dilepton invariant mass. The results show an energy-scaling behavior of the intrinsic $k_{\mathrm{T}}$parameters, independent of the dilepton invariant mass at a given center-of-mass energy. 

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5. On the expected purity of photometric galaxy surveys targeting the Cosmic Dawn

   https://doi.org/10.1093/mnras/stad1799  

   Furlanetto, Steven_R; Mirocha, Jordan (June 2023, Monthly Notices of the Royal Astronomical Society)

   ABSTRACT Over the last three decades, photometric galaxy selection using the Lyman-break technique has transformed our understanding of the high-z Universe, providing large samples of galaxies at $$3 \lesssim z \lesssim 8$$ with relatively small contamination. With the advent of the JWST, the Lyman-break technique has now been extended to z ∼ 17. However, the purity of the resulting samples has not been tested. Here, we use a simple model, built on the robust foundation of the dark matter halo mass function, to show that the expected level of contamination rises dramatically at $$z \gtrsim 10$$, especially for luminous galaxies, placing stringent requirements on the selection process. The most luminous sources at $$z \gtrsim 12$$ are likely at least 10 000 times rarer than potential contaminants, so extensive spectroscopic follow-up campaigns may be required to identify a small number of target sources. 

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