English

Discovery of a Nearby Low-Surface-Brightness Spiral Galaxy

Astrophysics 2009-10-31 v1

Abstract

During the course of a search for compact, isolated gas clouds moving with anomalous velocities in or near our own Galaxy (Braun and Burton 1998 A&A, in press), we have discovered, in the data of the Leiden/Dwingeloo survey (Hartmann and Burton 1997, Atlas of Galactic Neutral Hydrogen, CUP) of Galactic hydrogen, the HI signature of a large galaxy, moving at a recession velocity of 282 km/s, with respect to our Galaxy. Deep multicolor and spectroscopic optical observations show the presence of star formation in scattered HII regions; radio HI synthesis interferometry confirms that the galaxy is rich in HI and has the rotation signature of a spiral galaxy; a submillimeter observation failed to detect the CO molecule. The radio and optical evidence combined suggest its classification as a low-surface-brightness spiral galaxy. It is located in close spatial and kinematic proximity to the galaxy NGC 6946. The newly-discovered galaxy, which we call Cepheus 1, is at a distance of about 6 Mpc. It is probably to be numbered amongst the nearest few LSB spirals.

Keywords

Cite

@article{arxiv.astro-ph/9810432,
  title  = {Discovery of a Nearby Low-Surface-Brightness Spiral Galaxy},
  author = {W. B. Burton and R. Braun and R. A. M. Walterbos and C. G. Hoopes},
  journal= {arXiv preprint arXiv:astro-ph/9810432},
  year   = {2009}
}

Comments

13 page LaTeX, requires aastex, 4 GIF figures. Accepted for publication in the AJ, January 1999