Observations of Late-Type Variable Stars in the Water Vapor Radio Line. The Long-Period Variable R Cassiopeia

Astronomy and Astrophysics – Astronomy

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

2

Scientific paper

Observations of circumstellar maser emission from the long-period variable R Cas in the 1.35-cm water-vapor line are reported. The observations were carried out on the 22-m radio telescope of the Pushchino Radio Astronomy Observatory in 1980 2003 (JD=2444409 2452724). Over the 23 years of observations, strong flares in the H2O line profile were recorded in 1982 (with a peak flux density up to 400 Jy) and 1986 1989 (up to 750 Jy). Subsequently, from 1990 to March 2003, the H2O line flux was usually below the detection threshold of the radio telescope (<5 10 Jy). Episodic small increases of the emission with peak flux densities of 20 60 Jy were observed. The variations of the H2O line flux F are correlated with variations in the visual brightness of the star. The phase delay Δγ of the F variations relative to the optical light curve of R Cas ranged from 0.2 0.3P during the observations (P=430.46d is the star's period). A model for the variability of the H2O maser in R Cas is discussed. If the variations are due to periodic impacts by shock waves driven by the stellar pulsations, the time for the shock to travel from the photosphere to the inner boundary of the H2O-masing shell may reach 2 4P. The flares could be due to transient episodes of enhanced mass loss by the star or to the propagation of an exceptionally strong shock from the stellar surface.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Observations of Late-Type Variable Stars in the Water Vapor Radio Line. The Long-Period Variable R Cassiopeia does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Observations of Late-Type Variable Stars in the Water Vapor Radio Line. The Long-Period Variable R Cassiopeia, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Observations of Late-Type Variable Stars in the Water Vapor Radio Line. The Long-Period Variable R Cassiopeia will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1181400

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.