A new sample of OH/IR stars in the Galactic center

Abstract

Two independent, largely overlapping 1612 MHz data sets were searched for OH/IR stars in the Galactic center. One set, taken with the Very Large Array in the period 1988 to 1991, consists of 17 epochs mon- itoring data of Van Langevelde et al. (1993). The other set was observed in 1994, using the Australia Telescope Compact Array. This article describes the data reduction procedures as well as a dierent way of searching image cubes for narrow line sources, and lists 1 a total of 155 double peak OH maser detections within 18 0 or 40 pro- jected parsecs of Sagittarius A*, the compact radio contin- uum source in the Galactic nucleus. Presented are 65 for- merly unseen double peaked 1612 MHz emitters, of which 52 are OH/IR stars. Also given are 3 single peak sources, which we believe to be masers of OH/IR stars. Apart from being less bright in their 1612 MHz OH maser line, the previously unknown OH/IR stars do not seem to be dier- ent from the previously known population of OH/IR stars in the Galactic center. We nd that the OH/IR star OH maser luminosity distribution peaks at LOH 10 43:4 pho- tons per second. Further physical and kinematical analysis of the new sample will be presented in additional papers. 1 Tables 2 and 3 are also available in electronic form at CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5), or via the WWW at http://cdsweb.u-strasbg.fr/Abstract.html. Figures 4 and 5 are only published electronically and obtain- able from http://www.edpsciences.com