4 Comments on individual sources

WB89 1086: The Digital Sky Survey image shows Bran 96 as a slightly elongated (50 $^{\prime \prime }$ approximately in the east-west direction) nebulosity centered at the PSC position. Some obscuration might be discernible 30 $^{\prime \prime }$ north of this position where we find the weak C¹⁸O maximum in Fig. 6. Also the CS emission is weak. Northeast of the PSC position there is a 4$\sigma$ detection which seems real and is visible as the strongest (CS) peak in Fig. 6. WB89 1086 shows only emission centered at 62-64 km$\,$s^-1, which is associated with the PSC source. Although the spectrum taken by WB89 suggested the presence of broad wing emission, this is not confirmed by the present data.

WB89 1099: The velocity of the main component is about 5.5 km$\,$s^-1. Emission at higher velocities is detected SE of the PSC position and NW of the PSC position (9.5-10 km$\,$s^-1). In addition, at most positions, except SE of the PSC position, we find emission at 3.5-4.5 km$\,$s^-1, which close to the PSC position is visible only as a shoulder of the main component, and difficult to separate from it. At most positions there is also very weak (<1 K) emission at about -1 km$\,$s^-1, which is too faint to derive its distribution. ¹²CO emission towards this source has been mapped with the SEST also by Olberg et al. ([1989]) and Nielsen et al. ([1998]). The latter authors in addition mapped ¹³CO, and observed some positions in C¹⁸O, and CS. CS(2-1), CO(2-1), and 1.3 mm continuum emission were observed towards this object (DC 253.3-1.6) by Henning & Launhardt ([1998]). We note that Nielsen et al. ([1998]) consider the 4 km$\,$s^-1 component to be associated to the main line at 5.5 km$\,$s^-1 (in their Fig. 7). However this component was also detected in ¹³CO and appears to be stronger at larger distances from the PSC position. It might be gas moving away from the main part of the globule CG 30 (but which is still associated with it). HH 120 is located 5 $^{\prime \prime }$ north of the PSC position, close to the southern maximum of $T_{\rm {A}}^*$ (see Fig. 3) (the northern peak is slightly stronger: 12.1 K vs. 11.8 K). The distribution of blue and red outflow emission in Fig. 4 agrees with the results of Olberg et al. ([1989]) and Nielsen et al. ([1998]), with a stronger red wing east of the PSC position and a weaker blue wing west of it. The mass that we derived is slightly higher than the one by Nielsen et al. ([1998]) (after correcting for the different adopted distance) because these authors assumed that the gas is optically thin. The other parameters show larger differences due to the different methods used for calculating them.

WB89 1135: There is some foreground emission at about 44 km$\,$s^-1, mainly to the SE of the PSC position, but it can be clearly separated from the cloud emission, which is at about 54 km$\,$s^-1. The source is located near the south eastern edge of a more extended cloud (the highest $T_{\rm {A}}^*$ value of 9.8 K is found in our map at offset (-80 $^{\prime \prime }$, 60 $^{\prime \prime }$)). No optical emission is visible towards this source on the Digital Sky Survey image.

WB89 1173: This source is associated with the bright rimmed cloud 55 found on the ESO R print by Sugitani & Ogura ([1994]). The rim approximately follows the lowest contours in Fig. 3. The relatively high temperature ( $T_{\rm {A}}^*=26$ K, i.e. $T_{\rm {ex}}=41$ K) found north-west of the IRAS PSC position (higher than towards any other source in the sample) might be related to the presence of this bright rim, and caused by the same heating source. However, the $T_{\rm {A}}^*$ maximum is located at the position of some nebulosity visible at the Digital Sky Survey image, which does not show the rim. Liseau et al. ([1992]) and Massi et al. ([1999]) found only relatively weak NIR emission towards WB89 1173 (their source IRS 63). Massi et al. ([1997]) detected jet-like H₂ emission towards this source. Combined with the fact that we detect strong outflow emission, these data suggest that the embedded IRAS source is very young. Emission at velocities different from the main component (7-7.5 km$\,$s^-1) is found at 8.5-9.2 km$\,$s^-1 (N and W of the PSC position), and at 4-4.5 km$\,$s^-1 (SE of the PSC position). Both components have small line widths (1 km$\,$s^-1).

WB89 1181: This region shows only emission centered at 3-4 km$\,$s^-1, which is associated with the PSC source. Liseau et al. ([1992]) and Massi et al. ([1999]) detected strong NIR emission towards this source (their IRS 17), which shows no optical emission on the Digital Sky Survey (DSS) image. Massi et al. ([1997]) detected an H₂ jet, about 1$^\prime$ in size towards IRS 17. On the DSS there are two stars with associated nebulosity at offsets (40 $^{\prime \prime }$, 100 $^{\prime \prime }$) and (22 $^{\prime \prime }$, 138 $^{\prime \prime }$) from the PSC position, which might be associated with the CO cloud. They are located in a $T_{\rm {A}}^*$ minimum in Fig. 3.

WB89 1187: In addition to the main component near 13 km$\,$s^-1, most spectra away from the centre show an additional narrower line at 9-10.3 km$\,$s^-1. Near the PSC position, a comparison of ¹²CO and ¹³CO spectra suggests the presence of self-absorption (the ¹³CO maximum and a ¹²CO dip are at the same velocity). However, considering all positions it is more likely that there are really two components everywhere and the single (but broad) ¹³CO peak is caused by two lines that are close in velocity. At two positions there is also emission at about 5 km$\,$s^-1. This source is associated with the NIR source IRS 19 (Liseau et al. [1992]; Massi et al. [1999]) and is optically invisible. Very weak H₂ emission was found about 1$^\prime$ east of the PSC position (Massi et al. [1997]).

WB89 1189: The velocity of the peak CO emission near the PSC position is about 1.5 km$\,$s^-1, whereas at (positive and negative) offsets in $\delta$, velocities are about 3.3 km$\,$s^-1. We assume that this is the same component, showing a velocity gradient (see also Fig. 8, where there is a similar, but smaller gradient). From the line profiles we conclude that NW of the PSC position there is an additional component at 3.6-4 km$\,$s^-1. Other components are found at 6-7.5 km$\,$s^-1and at 12.5-13.5 km$\,$s^-1. NIR emission was detected towards WB89 1189 by Liseau et al. ([1992]) and Massi et al. ([1999]) (source IRS 20). This source is optically invisible. A small bipolar H₂ jet (extent about 5 $^{\prime \prime }$ towards both sides of a central object) was found by Massi et al. ([1997]), and is located north of the CS and C¹⁸O clumps.

WB89 1262: This source (G 270.26+0.83) was observed in several molecular transitions by Zinchenko et al. ([1995]) and Lapinov et al. ([1998]). Our CS(2-1) map looks similar to the one from those authors, however we find that the maximum is close to the IRAS PSC position rather than near (-30 $^{\prime \prime }$, 30 $^{\prime \prime }$).

WB89 1275: The optical image of RCW 42 shows a dust lane which is coincident with the distribution of peak $T_{\rm {A}}^*$ of ¹²CO in Fig. 3. There are no radio continuum maps available which would show whether this dust lane is seen in projection towards RCW 42, or actually divides the region into two parts. In this source the CO maximum is displaced from the PSC position to the NE. The strongest component is at 36-38 km$\,$s^-1, whereas another one is visible at most positions at 39-46 km$\,$s^-1, which is difficult to separate. A third but weak component is at about 28-34 km$\,$s^-1 in the western part of the mapped region. At two positions south of the source there is emission at 20 km$\,$s^-1. The broad line profiles in the ¹²CO map are interpreted as the superposition of two separate emission profiles, both without signs of outflow. The secondary (39-46 km$\,$s^-1) velocity component has its maximum south of the dust lane where there is optical emission, and might be located behind RCW 42.