5,505 research outputs found
The COINS Sample - VLBA Identifications of Compact Symmetric Objects
We present results of multifrequency polarimetric VLBA observations of 34
compact radio sources. The observations are part of a large survey undertaken
to identify CSOs Observed in the Northern Sky (COINS). Compact Symmetric
Objects (CSOs) are of particular interest in the study of the physics and
evolution of active galaxies. Based on VLBI continuum surveys of ~2000 compact
radio sources, we have defined a sample of 52 CSOs and CSO candidates. In this
paper, we identify 18 previously known CSOs, and introduce 33 new CSO
candidates. We present continuum images at several frequencies and, where
possible, images of the polarized flux density and spectral index distributions
for the 33 new candidates and one previously known but unconfirmed source. We
find evidence to support the inclusion of 10 of these condidates into the class
of CSOs. Thirteen candidates, including the previously unconfirmed source, have
been ruled out. Eleven sources require further investigation. The addition of
the 10 new confirmed CSOs increases the size of this class of objects by 50%.Comment: 24 pages, incl 8 figures. Accepted for publication in ApJ. Figure
quality degraded in the interests of space, full gzipped PS version also
available at http://www.ee.nmt.edu/~apeck/papers
Observations of extragalactic masers in bright IRAS sources
We report the first results of an ongoing survey at 22 GHz with the 100-m
Effelsberg telescope to search for water maser emission in bright IRAS sources.
We have detected water vapor emission in IC 342. The maser, associated with a
star forming region ~10-15 arcsec west of the nucleus, consists of a single 0.5
km/s wide feature and reaches an isotropic luminosity of 0.01 L(sun) (D = 1.8
Mpc). Our detection raises the detection rate among northern galaxies with IRAS
point source fluxes S(100micron) > 50 Jy to 16%.Comment: 6 pages, 3 figures. Proceeding of the conference "SRT: the impact of
large antennas on Radio Astronomy and Space Science", Cagliari, Italy, 7-10
Nov. 2001, Eds. Porceddu et al. Needs srt_style.st
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