The IAC Stripe 82 Legacy Project: a wide-area survey for faint surface
  brightness astronomy
  We present new deep co-adds of data taken within Stripe 82 of the Sloan
Digital Sky Survey (SDSS), especially stacked to reach the faintest surface
brightness limits of this data set. Stripe 82 covers 275 square degrees within
-50 < RA < +60 and -1.25 < Dec. < +1.25. We discuss the steps of our reduction
which puts special emphasis on preserving the characteristics of the background
(sky + diffuse light) in the input images using a non-aggressive sky
subtraction strategy. Our reduction reaches a limit of ~28.5 mag/arcsec^2 (3
sigma, 10x10 arcsec^2) in the r band. The effective surface brightness limit
(50% completeness for exponential light distribution) lies at <mu_e(r)> ~ 25.5
mag/arcsec^2. For point sources, we reach 50% completeness limits (3 sigma
level) of (24.2,25.2,24.7,24.3,23.0) mag in (u,g,r,i,z). This is between 1.7
and 2.0 mag deeper than the single epoch SDSS releases. The co-adds show point
spread functions with median FWHM values ranging between 1 arcsec in i and z to
1.3 arcsec in the u band. The imaging data are made publicly available at
http://www.iac.es/proyecto/stripe82. The release includes deep co-adds and
representations of the PSF for each field. Additionally, we provide object
catalogues with stars and galaxies confidently separated until g~23 mag. The
IAC Stripe 82 coadds offer a rather unique possibility to study the low surface
brightness universe, exemplified by the discovery of stellar streams around
NGC0426 and NGC0936. We also discuss further science cases like stellar haloes
and disc truncations, low surface brightness galaxies, the intra-cluster light
in galaxy clusters and the diffuse emission of Galactic dust known as Galactic
Cirrus.
