In a previous paper (Slysh et al. 1994, Paper I) we reported results
of the extensive search for OH main line emission from a sample of IRAS
point sources selected by color criteria from Wood & Churchwell (1989). The
sample was restricted to a region outside the galactic plane with galactic
latitude . This search was an extension of the OH masers
search towards IRAS sources brighter than 1000 Jy at 60 and 100
m by
Cohen et al. (1988). Several new relatively weak masers were detected as
well as thermal OH sources associated with dark clouds. The general
conclusion from Paper I was that the detection rate of OH masers from IRAS
sources was correlated with their far-infrared flux corroborating a similar
conclusion by Moore et al. (1988).
The second objective of the search was to detect OH masers less affected by
interstellar scattering. This would allow to study maser structures with the
high angular resolution of VLBI observations. From pulsar data, it is known
that the amount of scattering strongly depends on galactic latitude. For this
reason, we selected IRAS sources with galactic latitude
. From
pulsar observations, it is also known that the strength of the scattering
depends on galactic longitude since the scattering medium is concentrated
to the galactic center region. Thus, in the second survey reported in this
paper, we also included low latitude IRAS sources in the anticenter region.
Also, sources selected for the first survey which had not been observed due
to the lack of telescope time, were observed during this second survey.
Finally, several IRAS cores from the list of Wood et al. (1994),
masers and bipolar outflows, were added to the observing list.
Table 1: Masers. Column 1 contains IRAS names, or other names. Column 2 -
galactic coordinates. Columns 3, 4 and 5
- Gaussian fits for the 1667 MHz line. Columns 6, 7 and
8 - Gaussian fits for the 1665 MHz line.
Right and left circular polarizations are designated by R
and L, while H and V stand for horizontal and vertical linear polarizations.
Capital T is used when a line was supposed to be thermal
Table 2: Thermal sources.
Column 1 contains IRAS or other names. Column 2 - associations of an
IRAS source with nebulae of Lynds. Column 3 - galactic
coordinates. Columns 4, 5, 6 and 7 - results
of Gaussian fits. Column 8 contains estimates of OH column density. Column 10 and
11 - CO radial velocities with the corresponding references. Column 11 - name
of associated IRAS cloud or core (Wood et al. 1994)