Abstract. Seven-color CCD photometry in the Vilnius photometric system of 279 stars down to V -15 mag in the open cluster M 67 area is obtained. 13 standard stars in the cluster are measured photoelectrically. Photometric spectral types have been determined for all the stars. The reddening of the cluster is found to be EB-V = 0.045, the true distance modulus is 9.38 mag and the age is 4X10 9 years.
In the area covering the complex of the North America and Pelican nebulae we identified 13 faint stars with J-H and H-K s color indices which simulate heavily reddened O-type stars. One of these stars is CP05-4 classified as O5 V by Comerón and Pasquali (2005). Combining magnitudes of these stars in the passbands I C , J, H, K s and [8.3] we were able to suspect that two of them are carbon stars and five are late M-type AGB stars. Interstellar extinction in the direction of these stars was estimated from the background red clump giants in the J-H vs. H-K s diagram and from star counts in the K s passband. Four or five stars are found to have a considerable probability of being O-type stars, contributing to the ionization of North America and Pelican. If they really are O-type stars, their interstellar extinction A V should be from 16 to 35 mag. Two of them seem to be responsible for bright E and J radio rims discovered by Matthews & Goss (1980).
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