next previous
Up: The ATCA/VLA OH

4. Results

  figure273
Figure 2: The longitude-latitude diagram and the longitude-velocity diagram for all objects of Table 1. Features in these diagrams will be discussed in a future article

In Table 1 all OH sources found using the procedures described in Sects. 2, 3 are listed. In total there are 307 sources, 162 of which have been identified with known OH masers. The references for previous OH detections are given in Table 2. Of the 307 sources, we visually identified 245 as having double-peaked (D, see prototype #17) and 58 as having single-peaked (S, see prototype #13) spectra. The remaining four were classified as having irregular (I) spectra, consisting of three or more clearly separated peaks (prototype #123). A reliable IRAS identification is found for 201 sources. For each source the table gives an entry number (Col. 1), the OHtex2html_wrap_inline1551 name (Col. 2), a type (D,S,I) identifier (Col. 3), position in J2000 coordinates (Cols. 4, 5), a measure of the error in the positions (Col. 6), the distance from the source to the pointing centre (Col. 7), the peak, stellar and outflow velocities (Cols. 8 to 11), the peak fluxes (Col. 12, 13), the noise in the field where the source was detected (Col. 14, velocity resolution 1.45 tex2html_wrap_inline1553), the number of the reference to previous observations if applicable (Col. 15), the name of the nearest IRAS point source (Col. 16) and the distance to this nearest IRAS point source expressed as a fraction of the corresponding IRAS error ellipse (Col. 17). A detailed discussion of the data set is given in Sect. 5.

In Fig. 2 (click here) the longitude-latitude diagram and longitude-velocity diagram are shown for all 307 sources. The spectra for all the sources in Table 1 are shown in Fig. 6 (click here). They are displayed with 50 tex2html_wrap_inline1555 on either side of the stellar velocity. The channel width used in the spectra is 1.45 tex2html_wrap_inline1557\ which is equal to the velocity resolution. Along the upper border of each spectrum the entry number of the source in Table 1 is given, along with the usual OHtex2html_wrap_inline1559 name, its identification as double-peaked, single-peaked or irregular source and the number of the reference in the case of previously known sources.

To give a fair view of the data quality, spectra were extracted with the MIRIAD routine UVSPEC from the original visibilities, without any removal of interference. Spectral baselines were then fitted with polynomials of order up to three. This enables us to determine accurate flux densities although interference signals can slearly be seen in the spectra of some sources. Also, sidelobes from neighbouring stars are present in some spectra (positive as well as negative). If confusion is possible, the real peaks are indicated by an asterisk (e.g. spectrum #109).


next previous
Up: The ATCA/VLA OH

Copyright by the European Southern Observatory (ESO)
web@ed-phys.fr