Volume 22, Issue 3

Magnitudes and color indices in the Vilnius seven-color system were determined for 1752 stars down to V = 19.5 mag in the direction of the open cluster M29 (NGC 6913). The region is centered at RA = 20:24, DEC = +38:30 (J2000) and covers an area of 1.5 sq. deg. The photometric data are used to classify about 70% of stars in spectral and luminosity classes and peculiarity types.

We present the results of CCD photometry in the seven-color Vilnius system for 922 stars down to V ~ 17 mag in a 1.5 square degree field at the northern edge of the HII region Sh2-205, at the Perseus and Camelopardalis border. Using the intrinsic color indices and photometric reddening-free Q- parameters, two-dimensional spectral types for most stars are determined.

The results of CCD photometry in the seven-color Vilnius system are given for 727 stars down to V ~ 17 mag in a 1.5 square degree field in the region of dark cloud TGU H994 P1 (or LDN 1399, LDN 1400 and LDN 1402) in Camelopardalis. Using the intrinsic color indices and photometric reddening-free Q -parameters, two-dimensional spectral types for 73% of stars are determined.

The star V2282 Sgr is positionally consistent with a strong Chandra X-ray and a Spitzer /IRAC mid-infrared source. We derived its long-term I -band light curve from the photographic archives of the Asiago and Catania Observatories, covering the years from 1965 to 1984. Also, CCD R C photometry of 2009 was re-analyzed. Optical spectra were collected at the Loiano Observatory in 2011 and 2012. J,H,K s photometry, obtained from several sources in different epochs was compared and the Spitzer images were re-analyzed. V2282 Sgr was found to be irregular variable in all wavelengths. Spectroscopically, it shows strong emission features (H Balmer lines, [N II] 6584Å and [O III] 5007/4959Å) while the Na I D-doublet is very strong, indicating a circumstellar envelope. A single thermal energy distribution cannot reproduce the observed SED, while it can be explained as the sum of a G-type star plus a variable circumstellar disk, which mimics YSO of class 0/I. Most likely, V2282 Sgr is a 1–2 M ⊙ mass pre-main-sequence star with an accretion disk.