New OB Stars in the Field of the Havlen-Moffat 1 Galactic Open Cluster

GAMEN, R. C.; MORRELL, N. I.

Pucon, Chile

Congreso; XI IAU Regional Latin American Meeting of Astronomy; 2005

IAU

Havlen-Moffat 1 (HM-1) is a poorly known, highly reddened open cluster situated in the inner part of our Galaxy. HM-1 was first studied by Havlen & Moffat (1977, AA, 58, 351), who identified 2 Wolf-Rayet (WR), 2 Of, and 2 O8 stars. Two additional Of stars were later classified by Massey et al. (2001, AJ, 121, 1050). When attempting to estimate the distance to HM-1, Havlen & Moffat (1977, AA, 58, 351) found 3.3 Kpc via main-sequence fitting and 2.5 Kpc via spectroscopic parallaxes; and Vázquez & Baume (2001, AA, 371, 908) obtained 3.3 Kpc from the ZAMS superposition. With the goal of learning more about the early-type population of HM-1, and to solve the uncertainty about its distance, we observed the spectra of all of its known probable members with the WFCCD spectrograph attached to the 2.5-m du Pont telescope at Las Campanas Observatory. Here we present for the first time the spectra of several probable members of HM-1, including 20 new OBtype stars, and use them to estimate a new spectroscopic distance.