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arXiv · 1910.03078

On the environment of Low Surface Brightness galaxies at different scales

Luis Enrique Pérez-Montaño·Bernardo Cervantes Sodi
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Abstract

We select a volume-limited sample of galaxies derived from the SDSS-DR7 to study the environment of low surface brightness (LSB) galaxies at different scales, as well as several physical properties of the dark matter haloes where the LSB galaxies of the sample are embedded. To characterize the environment we make use of a number of publicly available value-added galaxy catalogues. We find a slight preference for LSB galaxies to be found in filaments instead of clusters, with their mean distance to the nearest filament typically larger than for high surface brightness (HSB) galaxies. The fraction of isolated central LSB galaxies is higher than the same fraction for HSB ones, and the density of their local environment lower. The stellar-to-halo mass ratio using four different estimates is up to $\sim$20% for HSB galaxies. LSB central galaxies present more recent assembly times when compared with their HSB counterparts. Regarding the $\lambda$ spin parameter, using six different proxies for its estimation, we find that LSB galaxies present systematically larger values of $\lambda$ than the HSB galaxy sample, and constructing a control sample with direct kinematic information drawn from ALFALFA, we confirm that the spin parameter of LSB galaxies is 1.6 to 2 times larger than the one estimated for their HSB counterparts.

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Luis Enrique Pérez-Montaño, Bernardo Cervantes Sodi. 2019-10-07. On the environment of Low Surface Brightness galaxies at different scales. https://doi.org/10.1093/mnras%2Fstz2847

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