English

NGC 6738: not a real open cluster

Astrophysics 2009-11-07 v2

Abstract

A photometric, astrometric and spectroscopic investigation of the poorly studied open cluster NGC 6738 has been performed in order to ascertain its real nature. NGC 6738 is definitely not a physical stellar ensemble: photometry does not show a defined mean sequence, proper motions and radial velocities are randomly distributed, spectro-photometric parallaxes range between 10 and 1600 pc, and the apparent luminosity function is identical to that of the surrounding field. NGC 6738 therefore appears to be an apparent concentration of a few bright stars projected on patchy background absorption.

Keywords

Cite

@article{arxiv.astro-ph/0306093,
  title  = {NGC 6738: not a real open cluster},
  author = {C. Boeche and R. Barbon and A. Henden and U. Munari and P. Agnolin},
  journal= {arXiv preprint arXiv:astro-ph/0306093},
  year   = {2009}
}

Comments

A&A, in press (compared with first submission to astro-ph, now Table 2 and Figure 4 are replaced with corrected versions)