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1. The KBSS–KCWI survey: the connection between extended Ly α haloes and galaxy azimuthal angle at z ∼ 2–3

   https://doi.org/10.1093/mnras/stab2383  

   Chen, Yuguang; Steidel, Charles C; Erb, Dawn K; Law, David R; Trainor, Ryan F; Reddy, Naveen A; Shapley, Alice E; Pahl, Anthony J; Strom, Allison L; Lamb, Noah R; et al (September 2021, Monthly Notices of the Royal Astronomical Society)

   ABSTRACT We present the first statistical analysis of kinematically resolved, spatially extended $$\rm Ly\alpha$$ emission around z = 2–3 galaxies in the Keck Baryonic Structure Survey (KBSS) using the Keck Cosmic Web Imager (KCWI). Our sample of 59 star-forming galaxies (zmed = 2.29) comprises the subset with typical KCWI integration times of ∼5 h and with existing imaging data from the Hubble Space Telescope and/or adaptive optics-assisted integral field spectroscopy. The high-resolution images were used to evaluate the azimuthal dependence of the diffuse $$\rm Ly\alpha$$ emission with respect to the stellar continuum within projected galactocentric distances of ≲30 proper kpc. We introduce cylindrically projected 2D spectra (CP2D) that map the averaged $$\rm Ly\alpha$$ spectral profile over a specified range of azimuthal angle, as a function of impact parameter around galaxies. The averaged CP2D spectrum of all galaxies shows clear signatures of $$\rm Ly\alpha$$ resonant scattering by outflowing gas. We stacked the CP2D spectra of individual galaxies over ranges of azimuthal angle with respect to their major axes. The extended $$\rm Ly\alpha$$ emission along the galaxy principal axes is statistically indistinguishable, with residual asymmetry of ≤2 per cent (∼2σ) of the integrated $$\rm Ly\alpha$$ emission. The symmetry implies that the $$\rm Ly\alpha$$ scattering medium is dominated by outflows in all directions within 30 kpc. Meanwhile, we find that the blueshifted component of $$\rm Ly\alpha$$ emission is marginally stronger along galaxy minor axes for galaxies with relatively weak $$\rm Ly\alpha$$ emission. We speculate that this weak directional dependence of $$\rm Ly\alpha$$ emission becomes discernible only when the $$\rm Ly\alpha$$ escape fraction is low. These discoveries highlight the need for similar analyses in simulations with $$\rm Ly\alpha$$ radiative transfer modelling. 

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2. Effect of Camera Parallax Angle on the Accuracy of Static Contact Angle Measurements

   https://doi.org/10.1021/acs.langmuir.3c03684  

   Johnson, Owen M; Mangolini, Filippo (March 2024, Langmuir)
3. On the α-q-Mutual Information and the α-q-Capacities

   https://doi.org/10.3390/e23060702  

   Ilić, Velimir M.; Djordjević, Ivan B. (June 2021, Entropy)

   null (Ed.)

   The measures of information transfer which correspond to non-additive entropies have intensively been studied in previous decades. The majority of the work includes the ones belonging to the Sharma–Mittal entropy class, such as the Rényi, the Tsallis, the Landsberg–Vedral and the Gaussian entropies. All of the considerations follow the same approach, mimicking some of the various and mutually equivalent definitions of Shannon information measures, and the information transfer is quantified by an appropriately defined measure of mutual information, while the maximal information transfer is considered as a generalized channel capacity. However, all of the previous approaches fail to satisfy at least one of the ineluctable properties which a measure of (maximal) information transfer should satisfy, leading to counterintuitive conclusions and predicting nonphysical behavior even in the case of very simple communication channels. This paper fills the gap by proposing two parameter measures named the α-q-mutual information and the α-q-capacity. In addition to standard Shannon approaches, special cases of these measures include the α-mutual information and the α-capacity, which are well established in the information theory literature as measures of additive Rényi information transfer, while the cases of the Tsallis, the Landsberg–Vedral and the Gaussian entropies can also be accessed by special choices of the parameters α and q. It is shown that, unlike the previous definition, the α-q-mutual information and the α-q-capacity satisfy the set of properties, which are stated as axioms, by which they reduce to zero in the case of totally destructive channels and to the (maximal) input Sharma–Mittal entropy in the case of perfect transmission, which is consistent with the maximum likelihood detection error. In addition, they are non-negative and less than or equal to the input and the output Sharma–Mittal entropies, in general. Thus, unlike the previous approaches, the proposed (maximal) information transfer measures do not manifest nonphysical behaviors such as sub-capacitance or super-capacitance, which could qualify them as appropriate measures of the Sharma–Mittal information transfer. 

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4. Mapping the twist-angle disorder and Landau levels in magic-angle graphene

   https://doi.org/10.1038/s41586-020-2255-3  

   Uri, A.; Grover, S.; Cao, Y.; Crosse, J. A.; Bagani, K.; Rodan-Legrain, D.; Myasoedov, Y.; Watanabe, K.; Taniguchi, T.; Moon, P.; et al (May 2020, Nature)
5. On the statistical treatment of the Cabibbo angle anomaly

   https://doi.org/10.1007/JHEP07(2020)068  

   Grossman, Yuval; Passemar, Emilie; Schacht, Stefan (July 2020, Journal of High Energy Physics)