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4 Comments on individual sources

L1287 (00338+6312). New detection. The 6.7 GHz methanol spectrum consists of two features at the velocities -23 km s-1 and -26.5 km s-1. The source is associated with a bipolar outflow, it was observed in the CO (1-0) line at the velocity -18.4 km s-1 and mapped by Snell et al. (1990). There is an OH maser at the velocity -22.6 km s-1 (Wouterlout et al. 1993). The 3.6 cm VLA observations, which have been made by Anglada et al. (1994) reveal the presence of a radio continuum source close to this position.

NGC281-W (00494+5617). New detection. The 6.7 GHz methanol spectrum contains a single feature at the velocity -29 km s-1. The source is associated with a bipolar outflow, it was observed in the CO (1-0) line at the velocity -30.5 km s-1 and mapped by Snell et al. (1990).

W3-IRS5 (02219+6152). New detection. Bipolar outflow; Bally & Lada (1983) detected CO emission towards this source with the velocity about -40 km s-1 which is close to the methanol velocity interval -47 km s-1- -39 km s-1.

02455+6034. The maser was also detected at 6.7 GHz by Lyder & Galt (1997). It is situated in the vicinity of W5. The spectrum obtained by Lyder & Galt in 1994 and spectrum obtained in this survey are similar. The difference in flux density, 24 Jy (this paper) and 32 Jy (Lyder & Galt 1997), can be attributed to a pointing offset of about 3 arcmin of our observation from the more accurate maser position, determined by Lyder & Galt (1997).

AFGL 5142 ($\bf 174.20-0.08$, 05274+3345). Bipolar outflow (Hunter et al. 1995). This source has been observed by Gaylard & Macleod (1993) who report a peak flus density of 85 Jy for the strongest feature at 2 km s-1, while we observe a flux density of 48 Jy. The position offset of the two observations (1 arcmin) and the the different frequency resolution, 0.22 km s-1 instead of 0.27 km s-1 (present work), can only partly account for this difference which is almost a factor of two. Moreover we note that a) in Gaylard & MacLeod (1993) the 2 km s-1 feature is about 8 times more intense than the feature at 4 km s-1, while in our spectrum this ratio is about 2.5; b) we observe a feature at 0.5 km s-1 which is missing in Gaylard & MacLeod observations. Therefore we conclude that AFGL 5142 is variable.

05480+2545.  New detection. There are two spectral features, at -14.5 km s-1 and -4.5 km s-1. CS (2-1) emission line is located between the methanol features at -9.4 km s-1 (Bronfman et al. 1996). OH maser at 1665 MHz has components in the velocity interval from -19 km s-1 to -4 km s-1 (Slysh et al. 1997).

AFGL 6366S (06056+2131).  This source was also detected by Caswell et al. (1995a). The 11 km s-1 detail, which is the strongest in our spectrum (about 30 Jy), is obviously a sidelobe response to S252. It was present in the spectrum of Caswell et al. (1995a), but with a much weaker intensity since the beam of their telescope was smaller. The source is a bipolar outflow (Snell et al. 1988).

17430-2822. The 6.7 GHz maser was found by Schutte et al. (1993). Our spectrum is similar to the one published by Schutte et al. (1993), and contains the same features at -10 km s-1, -3 km s-1, 0 km s-1 and 1 km s-1.

17436-2806. This source was also observed by van der Walt et al. (1995). Spectrum consists of a single feature at about 4 km s-1. We obtained the flux 20 Jy, about twice the flux published by van der Walt et al. This difference could be due to the higher velocity resolution 0.07 km s-1 in our survey compared to 0.22 km s-1 resolution of van der Walt et al. (1995).

17440-2825. This source belongs to the well-known molecular complex Sgr B2 where several centers of methanol maser activity exist. According to Caswell et al. (1995a) the lines, detected by us toward this IRAS object should be attributed to the centers of activity 0.64-0.04 and 0.65-0.05.

17463-3128. This IRAS source is also associated with OH maser of the Class Ib (emission only at 1667 GHz; Slysh et al. 1994b) at the velocity 9.4 km s-1. The 6.7 GHz maser was also detected by van der Walt et al. (1995). Spectra look similar, but the flux of the main feature at 5 km s-1 is different: 31 Jy in our spectrum against 17 Jy according to van der Walt et al. (1995). This difference is a result of our higher velocity resolution and disappears when we compare our low-resolution spectrum with that of van der Walt et al. (1995).

17589-2312. This source was also observed by van der Walt et al. (1995). The spectra are slightly different: the main feature at 27 km s-1 is stronger relative to the adjacent features in the van der Walt's et al. spectrum than in our. However, this difference disappears if we compare our low-resolution spectrum with the spectrum by van der Walt et al. The flux densities of this feature are similar: 79 Jy, obtained by van der Walt is close to our value 84 Jy.

10.3-0.15. This source was first detected by Schutte et al. (1993). They observed the IRAS source 18060 - 2005 which is within our beam. The spectra and line intensities are close to each other.

18064-2008. New detection. This source was observed but not detected by van der Walt et al. with an upper limit of 5 Jy while we observed a feature of 9 Jy, indicating that this source may be variable. Methanol maser lines were observed near 39 km s-1 and 10 km s-1 which is close to the recombination line velocity of HII region associated with this source and observed by Lockman (1989) at the velocity 14.2 km s-1.

18102-1800. New detection. The CS (2-1) line is at 21.1 km s-1 (Bronfman et al. 1996) which is close to the methanol velocity.

18128-1640. New detection. The CS (2-1) line is at the velocity 10.1 km s-1 (Larionov et al. 1998) as compared to 15.3 km s-1 for methanol.

18151-1208. The 6.7 GHz maser toward this source was observed by van der Walt et al. (1995) also. Both spectra consist of a single feature at 28 km s-1, but fluxes are different. Van der Walt et al. obtained the flux of 46 Jy whereas our value is 72 Jy. This difference could be result of a higher velocity resolution 0.07 km s-1 compared to 0.22 km s-1 resolution of van der Walt et al. (1995).

18236-1241. New detection. The source was not previously found by van der Walt et al. (1995) with the upper limit 5 Jy and we found 5 Jy. Turner (1979) observed OH maser at the velocity 42 km s-1, which is the same as the velocity of the brightest feature of methanol.

L379IRS2. New detection. The radial velocity of the strongest methanol feature 24.1 km s-1 is higher than the velocity of CS (2-1) line 19.5 km s-1 (Larionov et al. 1998).

18310-0825. The 6.7 GHz maser was first detected by Schutte et al. (1993). The spectra look quite different: Schutte et al. observed two narrow peaks between 87 and 89 km s-1 and we observed a single broad feature in the same velocity range. The peak flux density in the Schutte's et al. spectrum, 11 Jy is about twice as large as our value. The feature at 82 km s-1, detected by Schutte et al., is probably present in our spectrum also, but our poorer signal-to-noise ratio does not allow us to confirm it.

18316-0602. Our 6.7 GHz spectrum consists of a single feature at 42 km s-1. The same methanol feature was observed by van der Walt et al. (1995) and by Walsh et al. (1995) with the flux density a factor of two lower. This difference could be result of a higher velocity resolution 0.07 km s-1 compared to 0.22 km s-1 resolution of van der Walt et al. (1995).

18317-0845. This object was first detected by Schutte et al. (1993). A single feature at 64.5 km s-1 is present in both spectra. Schutte et al. reported the peak flux density of about 12 Jy, whereas our value is  8 Jy. However, poor signal-to-noise ratio does not allow us to conclude that the source is variable.

18324-0820. This source was first observed by Schutte et al. (1993). The main features at 80 km s-1 in both spectra have almost equal flux densities, whereas the feature at about 77 km s-1 is approximately twice as strong in our spectrum as in the Schutte's one. The observed positions differ by about 2.5', therefore we cannot conclude if the differences in the spectra are due to variability or to a complex spatial structure of the source.

18334-0733. This source was also observed by van der Walt et al. (1995). A single line at 115 km s-1 is present in both spectra. A small difference in the flux densities (33 Jy obtained by van der Walt et al. and  42 Jy in the spectrum obtained in this survey) can be attributed to calibration uncertainties and/or to noise in the spectra.

18341-0727. New detection. We detected 6.7 GHz methanol emission at 113 km s-1. Bronfman et al. (1996) observed the CS (2-1) line exactly at the same velocity.

18379-0500. New detection. Larionov et al. (1998) observed the CS (2-1) emission at the velocity 32.1 km s-1 close to the velocity of the brightest methanol feature 34.9 km s-1.

18379-0546. The 6.7 GHz line was detected also by van der Walt et al. (1995). The feature at about 104 km s-1 in both spectra has approximately the same intensity of 10 Jy. In our spectrum an additional feature at  116 km s-1 with flux density of about 9 Jy is present.

18416-0421. This maser was first detected by Schutte et al. (1993). There is a single asymmetric line peaked at about 81.5 km s-1 in both spectra. The shape of the shoulder toward larger radial velocities looks different, but the difference can be caused by rather high noise in Schutte's et al. spectrum.

18470-0044. We detected the 6.7 GHz emission toward this IRAS object. However, van der Walt et al. (1995) made an offset measurements and showed that the methanol maser is most likely associated with another IRAS source 18470-0049.

18488+0000. This maser was also observed by van der Walt et al. (1995). The spectra are similar, and a small difference in the flux densities (the peak flux density is 16 Jy according to van der Walt et al. (1995) and 22 Jy according to our measurements) can be explained by calibration errors or/and noise.

18497+0022. New detection. This source is associated with the reflection nebulae GGD 30 (see Gómez de Castro & Eiroa 1991). Larionov et al. (1998) detected the CS (2-1) emission at 79.1 km s-1 which is well outside the velocity range of the methanol emission from 100 to 108 km ${\rm s}^{-1}$.

18566+0408. New detection. Bronfman et al. (1996) observed CS (2-1) emission at 85.2 km s-1 within the methanol emission velocity range.

18572+0057. Van der Walt et al. (1995) also observed this source at 6.7 GHz. Our and their spectra look similar. Larionov et al. (1998) observed the CS (2-1) line at 46.3 km s-1, within the velocity range of the methanol emission 42 to 48 km s-1.

19220+1431. New detection. The source was not previously found by van der Walt et al. (1995). Bronfman et al. (1996) observed the CS (2-1) line at 68.8 km s-1, outside the velocity range of the methanol emission.

19388+2357. The 6.7 GHz line at 38 km s-1 was observed in this source also by Schutte et al. (1993). Bronfman et al. (1996) observed the CS (2-1) line at 34.4 km s-1.

19589+3320. New detection. Bronfman et al. (1996) observed the CS (2-1) line at -21.4 km s-1 and the methanol velocity is -26.4 km s-1. Larionov et al. (1998) observed the same CS line at -20.5 km s-1.

20062+3550. New detection. Radial velocity of methanol line is -2.8 km s-1. Water vapor maser emission was detected at the velocity -1.6 km s-1 by Brand et al. (1994). Bronfman et al. (1996) observed the CS (2-1) line at 1.1 km s-1.

20126+4104 (78.12+3.63). The 6.7 GHz maser was found first by MacLeod & Gaylard (1992). In November - December 1991 they detected a weak (7 Jy) emission in the velocity range -7.5 - -5.5 km s-1. We detected rather strong (about 60 Jy) double-peaked line in the same velocity range. A large difference in flux densities is probably due to pointing errors of MacLeod & Gaylard (1992) observations of this Northern source from the Southern Hemisphere. Bronfman et al. (1996) detected the CS (2-1) emission at -3.8 km s-1. The IRAS source is a center of well known bipolar outflow (Wilking et al. 1990).

20350+4126. New detection. OH emission was found towards this source at -8 km s-1 (Cohen et al. 1988). Bronfman et al. (1996) observed the CS (2-1) line towards this source at -3.1 km s-1 within the velocity range of methanol emission.

GL 2789 (21381+5000). New detection. The IRAS object is the center of a bipolar outflow (Rodríguez et al. 1981). A water vapor maser is located near this source (Comoretto et al. 1990) at the velocity -46.1 km s-1. Plume et al. (1992) detected CS (7 - 6) emission towards this source at the velocity -45.6 km s-1 which is slightly outside the velocity range of the methanol emission.

L1206 (22272+6358). New detection. Larionov et al. (1998) detected CS (2 - 1) emission at -10.1 km s-1 while methanol velocity is -11.3 km s-1. The IRAS source is probably a driving source for an unipolar outflow (Sugitani et al. 1989).

22551+6140. New detection. The velocity of 6.7 GHz methanol emision is in the interval from -5 km s-1 to -1 km s-1. CO emission was observed at the velocity -8.7 km s-1 (Wouterloot & Brand 1989), outside the methanol emission velocity range.



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