Astronomy and Astrophysics – Astrophysics
Scientific paper
2004-08-16
Astronomy and Astrophysics
Astrophysics
11 pages, 8 figures, accepted for publication in Astronomy and Astrophysics
Scientific paper
10.1051/0004-6361:20035686
Spectroastrometry is a technique which has the potential to resolve flux distributions on scales of milliarcseconds. In this study, we examine the application of spectroastrometry to binary point sources which are spatially unresolved due to the observational point spread function convolution. The technique uses measurements with sub-pixel accuracy of the position centroid of high signal-to-noise long-slit spectrum observations. With the objects in the binary contributing fractionally more or less at different wavelengths (particularly across spectral lines), the variation of the position centroid with wavelength provides some information on the spatial distribution of the flux. We examine the width of the flux distribution in the spatial direction, and present its relation to the ratio of the fluxes of the two components of the binary. Measurement of three observables (total flux, position centroid and flux distribution width) at each wavelength allows a unique separation of the total flux into its component parts even though the angular separation of the binary is smaller than the observations' point-spread function. This is because we have three relevant observables for three unknowns (the two fluxes, and the angular separation of the binary), which therefore generates a closed problem. This is a wholly different technique than conventional deconvolution methods, which produce information on angular sizes of the sampling scale. Spectroastrometry can produce information on smaller scales than conventional deconvolution, and is successful in separating fluxes in a binary object with a separation of less than one pixel. We present an analysis of the errors involved in making binary object spectroastrometric measurements and the separation method, and highlight necessary observing methodology.
Baines Debbie
Oudmaijer Rene D.
Porter John M.
No associations
LandOfFree
On the spectroastrometric separation of binary point-source fluxes 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 On the spectroastrometric separation of binary point-source fluxes, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and On the spectroastrometric separation of binary point-source fluxes will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-579460