Two-year Monitoring of MWC349 in Optical and Radio Domains
Abstract
MWC349, the unique hydrogen maser and laser star, was monitored quasi-simultaneously at millimeter and optical wavelengths from May 1997 through September 1999. This was the first attempt to search for correlation of the star's radiation in these two domains. In the present paper, we discuss the correlation of the optical emission (B,V,R,I) with radio continuum and the thermal component of radio recombination lines; the behavior of the masing component of recombination lines is presented elsewhere (see the abstract by Jisonna et al. in this issue). The observed amplitude of optical variations is consistent with previous photometry of the star. Variations in the radio continuum and in the thermal component of radio recombination lines are detected in this source for the first time. Both the radio and optical emission demonstrate monotonic decrease after June 1998, although the relative amplitude of the intensity change in radio was considerably larger than in optics. Between May 1997 and June 1998 the variations in radio and optics were visibly different, but this discrepancy may be due to larger errors of our radio observations in this early phase of the monitoring. Positive correlation between radio and optics is ascribed to the changing intensity of the ultraviolet radiation of the central star. This project was supported by the NSF/REU grant AST-9820555.
- Publication:
-
American Astronomical Society Meeting Abstracts
- Pub Date:
- December 1999
- Bibcode:
- 1999AAS...195.2505H