Evidence that the planetary candidate CVSO30c is a background star from
  optical, seeing-limited data
  We report serendipitous optical imaging of CVSO30c, an exoplanet candidate
associated with the pre-main sequence T Tauri star CVSO30 resides in the 25 Ori
stellar cluster. We perform PSF modeling on our seeing limited optical image to
remove the lights from the host star (CVSO30), allowing us to extract
photometry of CVSO30c to be g = 23.2+/-0.2 (statistic)+/-0.1 (systematic) and r
= 21.5+/-0.1 (statistic)+/-0.1 (systematic) magnitudes, respectively. This is
170 and 80 times too bright in the g and r-band, respectively, if CVSO30c were
an L0 substellar object as suggested by previous studies. The optical/infrared
colors of CVSO 30c are indicative of a stellar, not substellar object, while
the object's color-magnitude diagram position is strikingly inconsistent with
expected values for a low mass member of 25 Ori. Broad-band photometry for
CVSO30c is instead better fit by contaminants such as a background K3 giant or
M subdwarf. Our study demonstrates that optical seeing limited data can help
clarify the nature of candidate wide separation planet-mass companions in young
star-forming regions.
