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Title: The Nature of Low-surface-brightness Galaxies in the Hyper Suprime-Cam Survey

We present the statistical redshift distribution of a large sample of low-surface-brightness (LSB) galaxies identified in the first 200 deg2of the Hyper Suprime-Cam Strategic Survey Program. Through cross-correlation with the NASA–SDSS Atlas, we find that the majority of objects lie withinz< 0.15 or ∼500 Mpc, yielding a mass range ofM*≈ 107−109Mand a size range ofreff,g≈ 1−8 kpc. We find a peak in the distance distribution within 100 Mpc, corresponding mostly to ∼107Mgalaxies that fall on the known mass–size relation. There is also a tail in the redshift distribution out toz≈ 0.15, comprising more massive (M*= 108− 109M) galaxies at the larger end of our size range. We see tentative evidence that at the higher-mass end (M*> 108M), the LSB galaxies do not form a smooth extension of the mass–size relation of higher-surface-brightness galaxies, perhaps suggesting that the LSB galaxy population is distinct in its formation path.

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Publication Date:
Journal Name:
The Astrophysical Journal
Page Range or eLocation-ID:
Article No. 150
DOI PREFIX: 10.3847
Sponsoring Org:
National Science Foundation
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