FUSE Observations of the Interacting Binary U Cephei

Details FUSE Observations of the Interacting Binary U Cephei FUSE Observations of the Interacting Binary U Cephei

Jan 2009

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2009aas...21341023p&link_type=abstract

American Astronomical Society, AAS Meeting #213, #410.23; Bulletin of the American Astronomical Society, Vol. 41, p.215

Astronomy and Astrophysics

Astronomy

Scientific paper

U Cep (B7V + G8III-IV; P=2.49 d) is an active direct-impact Algol system in which the gas stream strikes the mass gainer's photosphere at an intermediate angle of about 45 deg. Seventeen observations of this system were carried through with the the Far Ultraviolet Explorer (FUSE) spacecraft between 2002-07. An elevated FUV flux is observed in the phase interval 0.6-0.1. At phase 0.83, when we view the trailing hemisphere of the system, obvious "shell-type'' features (mostly Fe III and similar species) can be seen. On 2004 February 9, we observed a rather spectacular rise in the level of the FUV flux during the course of a long 5 hour pointing. Summed flux data from the SiC 2A detector, that yields spectral coverage from 950-1000 A, began to rise at phase 0.625 and leveled off by phase 0.682. We interpret this observation as evidence for a "hot” accretion spot that rotated into our line-of-sight. The spot is centered at about phase 0.90, very close to the azimuth where the gas stream would impact photosphere of the B star. From the time it took for the spot to fully come into view, we can place a lower limit of 20 deg to its size. Associated with this accretion spot is a localized circumstellar (CS) plasma that hovers over the impact region. The localized CS plasma is probably formed as the result of a splash associated with the impacting gas stream. Since Fe III and similar species appear to be dominant in the gas, a T 18,000 K is inferred, which is at least 3,000 K higher than the photospheric temperature. An empirical model for the mass transfer in this system will be preesented.
The authors appreciate support from NASA grants NAG5-12253, NNG04GL17G, NNG07AF87G and NAS5-32985.

Affiliated with

Also associated with

No associations

Rating

FUSE Observations of the Interacting Binary U Cephei 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 FUSE Observations of the Interacting Binary U Cephei, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and FUSE Observations of the Interacting Binary U Cephei will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1701731