SiO Masers in a Scutum Massive Star Cluster of Red Supergiants

Jun-ichi Nakashima, Shuji Deguchi
2006 Astrophysical Journal  
We have detected five objects toward a Scutum massive star cluster of red supergiants in the SiO J p 1-0, p 1 or p 2 transitions. The radial velocity data indicate that four of the detections are cluster members and v v that the other, which is located close to the X-ray source AX 1838Ϫ0655, is a foreground object. The high velocity resolution of the maser lines provides a more accurate determination of the radial velocity (120 km s Ϫ1 ) and velocity dispersion (∼2 km s Ϫ1 ) of the cluster and,
more » ... of the cluster and, hence, of the distance (6.5 kpc) and luminosities of the stars. We discuss the implications of these measurements in constraining the relationships between SiO masers and mass-loss rate and modeling the cluster age and mass.
doi:10.1086/507466 fatcat:ie36a4m2vbcolcy4jjt6es33ue