AAS Meeting #194 - Chicago, Illinois, May/June 1999
Session 50. High Angular Resolution Science with the NRAO Very Long Baseline Array
Display, Tuesday, June 1, 1999, 10:00am-7:00pm, Southwest Exhibit Hall

[Previous] | [Session 50] | [Next]

[50.06] VLBI Imaging of the Gravity Probe B Guide Star IM~Pegasi

R.R. Ransom, N. Bartel, M.F. Bietenholz (York U.), D.E. Lebach, M.I. Ratner, I.I. Shapiro (CfA), J.-F. Lestrade (Obs. de Meudon)

Multi-epoch VLBI observations at 3.6 cm have been made of the RS~CVn binary star IM~Pegasi (HR~8703) in support of the NASA-Stanford relativity gyroscope experiment, Gravity Probe B (GP-B). We present images of IM~Peg produced from observations between January 1997 and August 1998. The images show a variety of radio emission structures. Phase-referenced maps from temporal subsets of the individual observing sessions show the evolution of the stellar emission structure over the period of each observation (12-15 hours). In particular, during several of our sessions we detected apparent source motions on the order of 1 mas on time scales of several hours. We discuss our astrophysical understanding of IM~Peg and examine the implications of our results for the GP-B experiment.

If the author provided an email address or URL for general inquiries, it is a s follows:


[Previous] | [Session 50] | [Next]