An Eccentric Accretion Disk In V691 Cra?

Astronomy and Astrophysics – Astrophysics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

Scientific paper

We present phase-resolved spectroscopic observations over a full orbital period (5.6 hr) of the low-mass X-ray binary, V691 CrA, obtained with IMACS on the 6.5-m Walter Baade telescope at Las Campanas Observatory in June 2010. This is part of an on-going program to construct modulated tomograms in selected optical lines that enable us to study the geometry of the accretion flow and to examine spectral signatures that differentiate between neutron stars and black holes. The images constructed via tomography provide one of the few paths toward detailed insight into the structure of spatially unresolved accretion processes and the dependence of that structure on the nature of the central condensed object. Apparent in the V691 CrA spectrum are emission lines from H, He, and Fe with Hα and HeII 4686 showing clear double peaks varying with phase. Using K1= 94.5 km/s (Casares et al., 2010) and K2 = 324 km/s (Jonker et al 2003) we confirm a systemic velocity γ = -43 km/s (Casares et al 2003). Using these values to generate Modulation maps in Hα we find strong disk emission and a bright spot at the point where the accreting stream hits the disk. The center of the disk appears significantly offset from the center-of-mass of the system indicating an eccentric disk that may be associated with precession. We will present these results in the context of both black hole and neutron star systems observed by our project. SDV has been supported in part by NSF grant AST-0507637 awarded to the Smithsonian Astrophysical Observatory and a Smithsonian Institution Scholarly Studies Grant.

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

An Eccentric Accretion Disk In V691 Cra? 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 An Eccentric Accretion Disk In V691 Cra?, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and An Eccentric Accretion Disk In V691 Cra? will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1402513

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