ar X iv : a st ro - p h / 04 02 01 1 v 1 1 F eb 2 00 4 OH Absorption in the Line of Sight Towards

ar X iv : a st ro - p h / 04 02 16 8 v 1 7 F eb 2 00 4 A search for wide ( sub ) stellar companions around extrasolar planet host stars

We present an overview of our ongoing systematic search for wide (sub)stellar companions around the stars known to host rad-vel planets. By using a relatively large field of view and going very deep, our survey can find all directly detectable stellar and massive brown dwarf companions (m>40 MJup) within a 1000 AU orbit.

ar X iv : a st ro - p h / 99 02 06 2 v 1 4 F eb 1 99 9 SOURCES OF RELATIVISTIC JETS IN THE GALAXY

ar X iv : a st ro - p h / 01 02 01 8 v 1 1 F eb 2 00 1 A One - sided , Highly Relativistic Jet from Cygnus X - 3

Very Long Baseline Array images of the X-ray binary, Cygnus X-3 were obtained 2, 4 and 7 days after the peak of a 10 Jy flare on 4 February 1997. The first two images show a curved one-sided jet, the third a scatter-broadened disc, presumably at the position of the core. The jet curvature changes from the first to the second epoch, which strongly suggests a precessing jet. The ratio of the flux...

ar X iv : a st ro - p h / 01 02 14 6 v 1 8 F eb 2 00 1 In the Shadow of the Accretion Disk : Higher Resolution Imaging

The physical conditions in the inner parsec of accretion disks believed to orbit the central black holes in active galactic nuclei can be probed by imaging the absorption (by ionized gas in the disk) of background emission from a radio counterjet. We report high angular resolution VLBI observations of the nearby (∼ 40 Mpc) radio galaxy NGC 4261 that confirm free-free absorption of radio emissio...

ar X iv : a st ro - p h / 03 02 10 3 v 1 5 F eb 2 00 3 Detection of OH Towards the Extreme Carbon Star IRC + 10216

We report the detection of the 1665 and 1667MHz main lines of OH (hydroxyl) and upper limits on the 1612MHz satellite line of OH towards the carbonrich AGB star, IRC+10216. We find a beam averaged fractional abundance x(OH) ∼ 4 × 10. This detection supports the identification by Melnick et al. (2001) of the 110−101 transition of water vapor with a 556.936GHz emission feature detected towards IR...