A Near-Infrared Narrow-band Imaging Survey to Search for Massive Stars in Cl 1806-20
Gemini Observatory, Southern Operations Center, La Serena, Chile, et
Department of Astronomy, University of Florida, Gainesville, FL 32611
Department of Astronomy, University of Florida, Gainesville, FL 32611
Department of Astronomy, University of Florida, Gainesville, FL 32611
Department of Astronomy, University of Florida, Gainesville, FL 32611, and Department of Physics and Astronomy, Louisiana State University, Baton Rouge, LA 70803
Abstract
We survey the environment surrounding Cl 1806-20 using near-infrared narrow-band imaging to search for Brgamma features indicative of massive stars. Using this technique, we successfully detect previously identified massive stars in the cluster. While we detect no new emission line stars, establishing a firm upper limit on the number of Wolf Rayets and Luminous Blue Variables, we do find several candidate OB supergiants, which likely represent the bulk of the heretofore undiscovered massive star population. Finally, we present spectroscopic evidence for emission-line variability in LBV 1806-20. Our results highlight the advantages of using narrow-band imaging to search for massive stars.