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arXiv · 2606.19862

Multi-band Structural Analysis of KiDS-selected Low Surface Brightness Galaxies with Hyper Suprime-Cam Imaging

Dipanjan Mitra·Kanak Saha
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Abstract

We present a homogeneous multi-band structural analysis of 205 KiDS-selected low surface brightness galaxy (LSBG) candidates using deep Hyper Suprime-Cam (HSC) $G$, $R$, and $I$-band imaging. Structural parameters were derived using single-component S\'ersic modeling with GALFIT. The sample is dominated by diffuse systems with low S\'ersic indices, with the distributions consistently peaking near $n\approx0.7$ across all bands. The estimated $B$-band central surface brightness distribution has a median value of $\tilde{\mu}_{0,B}=24.55$ mag arcsec$^{-2}$, indicating that the galaxies lie firmly within the low surface brightness regime. The catalog is strongly dominated by red systems, comprising 178 red LSBGs (87.3$\%$) and 27 blue LSBGs (12.7$\%$). Despite this color bimodality, the red and blue subsamples show similar structural properties, with no statistically significant differences in S\'ersic index, effective radius, axis ratio, or surface brightness distributions. The absence of a correlation between color and axis ratio further suggests that dust reddening is unlikely to be the primary driver of the red colors. Overall, the sample provides a well-characterized structural reference set of LSBGs in the HSC footprint and confirms that the KiDS selected candidates are predominantly genuine low surface brightness galaxies.

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Dipanjan Mitra, Kanak Saha. 2026-06-18. Multi-band Structural Analysis of KiDS-selected Low Surface Brightness Galaxies with Hyper Suprime-Cam Imaging. https://doi.org/10.3847/1538-4357/ae9d63

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