http://arxiv.org/abs/1510.04696
The detection of optical surface brightness structures in the sky with magnitudes fainter than 30 mag/arcsec^2 (3sigma in 10×10 arcsec boxes; r-band) has remained elusive in current photometric deep surveys. Here we show how present-day 10 meter class telescopes can provide broadband imaging 1.5-2 mag deeper than most previous results within a reasonable amount of time (i.e. <10h on source integration). In particular, we illustrate the ability of the 10.4 m Gran Telescopio de Canarias (GTC) telescope to produce imaging with a limiting surface brightness of 31.5 mag/arcsec^2 (3sigma in 10×10 arcsec boxes; r-band) using 8.1 hours on source. We apply this power to explore the stellar halo of the galaxy UGC00180, a galaxy analogous to M31 located at ~150 Mpc, by obtaining a surface brightness radial profile down to mu_r~33 mag/arcsec^2. This depth is similar to that obtained using star counts techniques of Local Group galaxies, but is achieved at a distance where this technique is unfeasible. We find that the mass of the stellar halo of this galaxy is ~4×10^9 Msun, i.e. 3+-1% of the total stellar mass of the whole system. This amount of mass in the stellar halo is in agreement with current theoretical expectations for galaxies of this kind.
I. Trujillo and J. Fliri
Mon, 19 Oct 15
19/44
Comments: 17 pages, 13 figures, submitted to MNRAS. Comments are welcome
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