VLA observations of CYG OB2 No. 5: Detection of a weak radio companion and new observations and models for the main component

Details VLA observations of CYG OB2 No. 5: Detection of a weak radio companion and new observations and models for the main component VLA observations of CYG OB2 No. 5: Detection of a weak radio companion and new observations and models for the main component

Feb 1994

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1994a%26a...282..547m&link_type=abstract

Astronomy and Astrophysics (ISSN 0004-6361), vol. 282, no. 2, p. 547-553

Astronomy and Astrophysics

Astrophysics

23

Eclipsing Binary Stars, Periodic Variations, Radio Emission, Radio Stars, Stellar Radiation, Brightness Temperature, Photosphere, Stellar Envelopes, Stellar Models, Synchrotron Radiation, Very Large Array (Vla)

Scientific paper

We present Very Large Array (VLA) observations of the contact binary star Cyg OB2 No. 5 obtained over the last four years. A weak (approximately 0.6 mJy at 6 cm) radio companion has been detected approximately 0.8 sec to the NE of the known main radio component. However, most of the radio continuum and the variability appear to be associated with the main component (that coincides in position with the optical contact binary). The centimeter continuum emission of the main component increased in 1989-1992 to levels similar to those observed in 1983-1986. The radio emission seems to alternate between a 'low' and a 'high' state with a period of about seven years. We derived its brightness temperature from 3.6 cm observations during a 'high' state, obtaining TB = 100 000 +/ 30 000 K. This large value rules out a possible thermal origin for the radio continuum emission. Several models are discussed to account for the characteristics of the radio emission from the main component. The most satisfactory consists of a synchrotron-emitting envelope produced near the outer region of the free-free radio phototsphere (approximately 1015 cm at cm wavelengths).

Affiliated with

Also associated with

No associations

Rating

VLA observations of CYG OB2 No. 5: Detection of a weak radio companion and new observations and models for the main component 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 VLA observations of CYG OB2 No. 5: Detection of a weak radio companion and new observations and models for the main component, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and VLA observations of CYG OB2 No. 5: Detection of a weak radio companion and new observations and models for the main component will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1013075