S. König, A. Eckart, C. Henkel, M. Garcia-Marin
A sample of nearby galaxies hosting low-luminosity type 1 quasi-stellar
objects (QSOs), previously studied in CO and HI emission lines, has been
searched for maser emission. Using the Effelsberg 100-m telescope, we observed
17 sources with redshifts of z<0.06 and {\delta}>-30{\deg} for emission in the
22 GHz water vapor maser transition. The sample objects have been drawn from a
wide-angle survey for optically bright QSOs (Hamburg /ESO survey, HES). No host
galaxies from the sample have been detected in the water maser emission line.
In this paper we review the discussion on the reasons for water megamasers
being rarely found in Seyfert 1 galaxies. Eight of them are bulge dominated and
probably of elliptical type (E/S0), whereas 6 have spiral geometry. Three of
the objects seem to be in a phase of merging/interaction. We found 3{\sigma}
upper limits for the flux density of 27 to 60 mJy at spectral resolutions of
~0.43 km/s. We furthermore find that the viewing angle to the line of sight to
the galaxy, under which the probability to detect megamaser emission is
highest, is about 6{\deg}.
View original:
http://arxiv.org/abs/1111.3245
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