HCO+ in the disk of AB Aur
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HCO+ (J=1-0) emission was detected with the Plateau de Bure Interferometer
towards the known disk around the Herbig Ae star AB Aurigae. The morphology
of the disk and the shape of the spectra are similar to the
13CO measurements by Mannings and Sargent (1997, ApJ 490, 792). However, the
spectra are much better resolved. The map of the integrated HCO+ (J=1-0)
line (left: green contours; levels 0.05 to 0.25 by 0.05 Jy/beam) is
overlaid with the NICMOS image by Grady et al. (1999, ApJ 523, L151).
Three spectra are displayed on the right. At the top, the
integrated spectrum over the region inside the 0.15 Jy/beam
contour level is shown. The positions of spectra in the middle
and at the bottom are marked with an arrow.
The strong variation of the HCO+ line profiles over the disk area is
caused by the rotation of the gas disk. More details, you will see
in Schreyer et al., A&A, 2003, in prep.
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