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Appendix A: Description of the H₂ outflows in Ophiuchus

We detected six new MHOs and 32 known MHOs, with 107 MHO features in total. We obtained the proper motion measurements for 86 MHO features. Table A.1 lists the information of each MHO feature.

In this section, we give a brief description of each MHO. Here we offer typically four images for each MHO, one H₂ image with the MHO and YSO identifications, one H₂ image with the proper motion measurements marked, one Ks image for comparison and one continuum-subtracted H₂ image to emphasize the MHO identifications.

• MHO 2102: the region ofMHO 2102 is shown in Fig. A.1.This MHO consists of two knots,MHO 2102a and MHO 2102b.Gómez et al. (2003) firstlyidentified this object in their H₂ narrowband images as [GSWC2003] 19 and Khanzadyan et al. (2004) associated it with HH 79 and HH 711 to the north according to the bow-like morphology of MHO 2102b. We obtained the proper motion (PM) measurements of this object. However, due to the low signal-to-noise ratio (SNR) of MHO 2102a in the first epoch image, the PM of MHO 2102a is uncertain. The PM vectors of MHO 2102 point back to the YSO [EDJ2009] 800 identified by Evans et al. (2009). Johnstone et al. (2000) also detected a sub-millimeter source about 7′′ to the southeast of [EDJ2009] 800. Based on the measured proper motions, we suggest [EDJ2009] 800 as the likely driving source of MHO 2102.

• MHO 2103: the region of MHO 2103 is shown in Fig. A.2. This object was firstly detected by Khanzadyan et al. (2004), who identified five H₂ emission line knots on H₂ narrowband images. In our SofI (2007) images, we detected three H₂ emission knots, including one new feature, MHO 2103c. MHO 2103a and b correspond to the previous detections of [KGS2004] f10-01e and f, respectively. Note that [KGS2004] f10-01a,b are located outside the coverage of our H₂ images and [KGS2004] f10-01c,g are too faint to show up in our H₂ images. We rejected [KGS2004] f10-01d as H₂ emission feature because it is invisible on our continuum-subtracted H₂ image, and we suggest it might actually be two barely resolved stars based on their morphologies in the Ks image. We did not obtain PM measurements for MHO 2103 because of the lack of previous epoch SofI data. Khanzadyan et al. (2004) proposed YLW 31 as the possible driving source due to the accurate alignment of the MHO 2103 knots together with MHO 2104 knots (see the description about MHO 2104) with respect to YLW 31. We note that MHO 2103b shows a nice bow shock morphology. Based on the alignment and morphology of the MHO 2103 features, we accepted the suggestion from Khanzadyan et al. (2004) that YLW 31 is the driving source of MHO 2103.

• MHO 2104: Fig. A.2 shows MHO 2104 and YSOs in the region. This object was also firstly detected by Khanzadyan et al. (2004), who identified two H₂ emission line knots on H₂ narrowband images. In our SofI (2007) images, we detected four H₂ emission knots, including two new features, MHO 2104b and c. MHO 2104a and d correspond to the previous detections of [KGS2004] f10-01h and i, respectively. We did not obtain PM measurements for MHO 2104 because of the lack of previous epoch SofI data. Khanzadyan et al. (2004) proposed YLW 31 as the possible driving source due to the accurate alignment of the MHO 2104 knots with respect to YLW 31. Based on the alignment and morphology of the MHO 2104 features, we agree with the identification by Khanzadyan et al. (2004) that MHO 2104 is driven by YLW 31.

• MHO 2105: Fig. A.3 shows the region of MHO 2105. We detected 27 H₂ emission features in MHO 2105 including six newly detected features (located in the red boxes II, III and IV in Fig. A.3). We also marked the position of the well-known Class 0 source VLA 1623 in Fig. A.3, which is the driving source of a well-collimated high-velocity CO molecular outflow (Andre et al. 1990; Dent et al. 1995; Nakamura et al. 2011). MHO 2105 is associated with the red-shifted lobe of the CO molecular outflow. Davis & Eisloeffel (1995) and Dent et al. (1995) discussed in detail the association between the CO molecular outflow and the H₂ emission features in this region. Gómez et al. (2003) suggested VLA 1623 as the driving source of most H₂ features in MHO 2105. Lucas et al. (2008) also detected part of the features in MHO 2105 using their UKIRT H₂ images (see B and D in Fig. 19 of Lucas et al. 2008). In this paper, we obtained the PM measurements for 24 features in MHO 2105 and the results of the PM analysis support the conclusion of Gómez et al. (2003). Figures A.4–A.6 show the zoomed in images for the red boxes in Fig. A.3. Note that for MHO 2105c,d,g,h,o,v, Caratti o Garatti et al. (2006) derived the PMs by comparing their H₂ images (March 2003) with those published by Davis & Eisloeffel (1995) (April 1993). Our PM measurements agree with their calculations with the exception of MHO 2105c. The position angle of MHO 2105c calculated by Caratti o Garatti et al. (2006) is about 243 degrees. Caratti o Garatti et al. (2006) suggested that the driving source of MHO 2105c might be another YSO located northeast of MHO 2105c rather than VLA 1623. However, our PM measurement for MHO 2105c based on the higher resolution images gives the position angle of 329 degrees, which supports the conclusion that VLA 1623 is the driving source of MHO 2105.

• MHO 2106: Fig. A.7 shows the region of MHO 2106. Dent et al. (1995) firstly detected three bright knots in MHO 2106 in their H₂ images. Gómez et al. (2003) identified 10 features of MHO 2106 using the deeper observations. Khanzadyan et al. (2004) also investigated this region, increasing the number of the detected features in MHO 2106 up to 13. Lucas et al. (2008) detected some features based on UKIRT H₂ images (named E in Fig. 19 of their paper). Our observations of this region are the deepest to date. We confirmed 14 H₂ emission features in MHO 2106. MHO 2106 is associated with the blue-shifted lobe of the CO molecular outflow, which is driven by VLA 1623 (Andre et al. 1990; Davis & Eisloeffel 1995; Dent et al. 1995; Nakamura et al. 2011). Gómez et al. (2003) and Khanzadyan et al. (2004) both suggested VLA 1623 as the driving source of MHO 2106 based on the morphology and the association with the CO outflow. We obtained the PM measurements for 10 knots in MHO 2106. However, the PM measurements for 7 faint features in MHO 2106 are uncertain due to the low SNRs for these features. The PMs of the three bright knots support the conclusion that MHO 2106 is driven by VLA 1623.

• MHO 2108: Fig. A.8 shows the region of MHO 2108. Khanzadyan et al. (2004) detected this object as a bow shape structure in their H₂ images. They suggested a YSO northeast of MHO 2108 as the driving source. Our deeper observations reveal a more complicated structure for MHO 2108. It consists of a bow-like structure, a faint knot, and a long tail connected to the infrared nebular around WL 18. The optical counterpart of MHO 2108 is HH 673 (Phelps & Barsony 2004). Phelps & Barsony (2004) also detected HH 673b ~ 40′′southeast of WL 18. They suggested that HH 673 and HH 673b belong to a bipolar outflow driven by WL 18. We obtained a PM measurement for MHO 2108, but the PM is uncertain because of the difference of morphology between the images in the two epochs. Based on the morphology of MHO 2108, we accepted the assumption from Phelps & Barsony (2004) that WL 18 is the possible driving source of MHO 2108.

• MHO 2109: Fig. A.8 also shows MHO 2109, which exhibits a bow shape in our H₂ images. Gómez et al. (2003) and Khanzadyan et al. (2004) both detected this object in their images. Gómez et al. (2003) suggested that WL 15 (Elias 2-29, located 24 to the east from MHO 2109 and situated outside of our image) as the driving source of MHO 2109. WL 15 is associated with a bipolar CO outflow (Bontemps et al. 1996; Sekimoto et al. 1997) and the red-shifted lobe roughly aligns with the direction of MHO 2109. Khanzadyan et al. (2004) confirmed the bow shape of MHO 2109 and they inferred that MHO 2108 and MHO 2109 arise from a flow connecting both knots with a flow direction to the northeast. Nakamura et al. (2011) investigated the CO outflows in L1688 using CO (J = 3–2) and CO (J = 1–0) mapping observations. They identified a CO outflow driven by the YSO LFAM 26. MHO 2109 is associated with the red-shifted lobe of this CO outflow. We obtained the PM measurement of MHO 2109. We found that the PM vector of MHO 2109 points to the direction of the northwest, which indicates that the driving source should be located in the southeast of MHO 2109. There are some YSOs in the southeast region. Here we suggest YLW 5 as the likely driving source just because that YLW 5 is the nearest YSO to MHO 2109.

• MHO 2110: MHO 2110 consists of three knots, MHO 2110a-c. Figure A.9 shows the region of MHO 2110. Khanzadyan et al. (2004) detected this object in their H₂ images. They suggested EM*SR 24 as the driving source of MHO 2110 because MHO 2110, together with MHO 2111 (see the following description) and several HH objects (HH 224, HH 709 and HH 418, which are situated outside of our image), is aligned along a NW-SE direction passing through EM*SR 24 (see. Khanzadyan et al. 2004, Fig. 3). For MHO 2110, we only obtained the uncertain PMs due to the low SNRs of the emission features. Therefore, we cannot associate MHO 2110 with any YSO based on our PM measurements.

• MHO 2111: Fig. A.10 shows the region of MHO 2111. MHO 2111 consists of two knots: MHO 2111a is a central knot with a diffuse nebula. MHO 2111b is an elongated knot. MHO 2111 has been detected by optical, near- and mid-infrared observations. Its optical counterpart is HH 224S. Zhang & Wang (2009) identified its mid-infrared counterpart using Spitzer/IRAC images. Phelps & Barsony (2004) identified HH 224S at the location of MHO 2111. They also detected several HH objects (HH 224N, HH 224NW1 and HH 224NW2, see Phelps & Barsony 2004, Fig. 12) to the northwest of HH 224S. According to the alignment of the HH 224 complex, Phelps & Barsony (2004) suggested [GY92] 193 (located ~7′ to the northwest and outside the boundary of Fig. A.10) as the driving source of HH 224S. Khanzadyan et al. (2004) detected MHO 2111 at H₂ 2.12 μm as the counterpart of HH 224S, but they did not detect any near-infrared counterparts of HH 224N, HH 224NW1, and HH 224NW2. Therefore they suggested that MHO 2111 might be driven by EM*SR 24, as MHO 2111, MHO 2110 and EM*SR 24 are aligned roughly along a line. However, Zhang & Wang (2009) suggested WSB49, the YSO closest to MHO 2111, as the driving source based on MHO 2111’s wide-cavity lobe morphology, which faces away from WSB 49. We obtained the PM measurements for MHO 2111, found that the PM vectors point back to WSB 49. Therefore, we confirmed the assumption from Zhang & Wang (2009) that WSB 49 is the likely driving source of MHO 2111.

• MHO 2112: MHO 2112 is a faint knot (see Fig. A.11). Khanzadyan et al. (2004) detected MHO 2112 in their H₂ images. They suggested that MHO 2112 is driven by YLW 16 based on the morphology and distribution of MHO features (see Khanzadyan et al. 2004, Fig. 5). MHO 2112 is too faint to measure the proper motion. We have no enough evidence to associate MHO 2112 with the nearby YSOs.

• MHO 2113: MHO 2113 is a bright knot (see Fig. A.11). Gómez et al. (2003) and Khanzadyan et al. (2004) both detected MHO 2113. Gómez et al. (2003) suggested that the nearest YSO [GY92] 235 as the driving source. Based on the morphology and the location of H₂ features (see Khanzadyan et al. 2004, Fig. 5), Khanzadyan et al. (2004) inferred that MHO 2113 may be part of the large H₂ outflow driven by YLW 15. We obtained the PM measurement for MHO 2113. The PM vector of MHO 2113 indicates that the driving source should be located in the north of MHO 2113. There are several YSOs in the north of MHO 2113. There is no strong evidence to associate MHO 2113 with the certain one of them. Therefore, here we accept the suggestion from Gómez et al. (2003) that [GY92] 235 is the likely driving source of MHO 2113.

• MHO 2114: MHO 2114 is a knot (see Fig. A.11). Khanzadyan et al. (2004) identified this object in their H₂ images. They proposed an association between MHO 2114 and the nearby YSO, [GY92] 235. The PM of MHO 2114 obtained by us indicates that the driving source should be located in the north. There are several YSOs in the north of MHO 2114, including [GY92] 235 and [GY92] 232. We have associated MHO 2113 with [GY92] 235 and it seems impossible that MHO 2113 and MHO 2114 constitute a bipolar outflow which is driven by [GY92] 235 because MHO 2113 and MHO 2114 are located in the same side of [GY92] 235. Therefore, here we suggest another possibility that MHO 2114 is driven by [GY92] 232 because the PM vector of MHO 2114 points back to [GY92] 232.

• MHO 2115: Fig. A.12 shows the region of MHO 2115. Gómez et al. (2003) detected six H₂ features in MHO 2115, corresponding to MHO 2115a-e,g. Khanzadyan et al. (2004) identified an additional feature, MHO 2115f, in this MHO. Lucas et al. (2008) also detected some features using the UKIRT H₂ images (named G in Fig. 19 of their paper). BBRCG 24 is a Class II source (Evans et al. 2009) and is the possible driving source of a CO molecular outflow (Sekimoto et al. 1997). Based on the morphology and distribution of MHO 2115 features, Gómez et al. (2003) and Khanzadyan et al. (2004) both suggested that these H₂ emission knots arise from multiple, overlapping flows. The PMs of the MHO 2115 features support this conclusion. We infer that MHO 2115b,d,e,f,g are driven by BBRCG 24 based on the position angles of the PM vectors and the fact that MHO 2115b,d,e,g are associated with the blue lobe of the CO outflow, while MHO 2115f is associated with the red lobe of the CO outflow (see Sekimoto et al. 1997, Fig. 2). The PM vectors of MHO 2115a,c indicate that MHO 2115a,c may be driven by another YSO and their driving source should be located in the southwest of MHO 2115a,c. We associate MHO 2115a,c with [GY92] 93, which is located ~9.5′ to the southwest (outside the boundary of Fig. A.12). HH 314 is located ~47′′ to the southwest of [GY92] 93. MHO 2115a,c and HH 314 may constitute a bipolar outflow driven by [GY92] 93.

• MHO 2116: MHO 2116 exhibits a bow shape in Fig. A.13. Based on the morphology of MHO 2116, Gómez et al. (2003) and Khanzadyan et al. (2004) suggested YLW 14 as the possible driving source of MHO 2116. The PM vector of MHO 2116 points back to YLW 14, supporting this suggestion. YLW 14 also drives a CO molecular outflow (see Sekimoto et al. 1997, Fig. 2) and MHO 2116 is roughly associated with the blue-shifted lobe of this CO outflow.

• MHO 2117: MHO 2117 shows a bow-like structure in Fig. A.13. Gómez et al. (2003) suggested that MHO 2117 and MHO 2116 share the same powering star and thus belong to the same flow. Khanzadyan et al. (2004) also detected MHO 2117. They suggested that the driving source should lie to the southeast of MHO 2117 based on the bow shock morphology of MHO 2117. Gómez et al. (2003) and Khanzadyan et al. (2004) also proposed WLY 2-48 (outside the boundary of Fig. A.13) as a possible driving source as this YSO is associated with a bipolar CO outflow (Bontemps et al. 1996). However, Nakamura et al. (2011) investigated the CO outflows in this region. They associated this CO outflow with Elias 2-32, which is located to the northeast of MHO 2117, rather than with WLY 2-48. Our PM measurement for MHO 2117 is uncertain as the morphology of MHO 2117 changed somewhat from 2000 to 2007. Moreover, the orientation of the PM vector of MHO 2117 is not in agreement with its bow-like morphology. Thus we can’t associate MHO 2117 with any ambient YSOs. The PM vector of MHO 2117 indicates that the possible driven source could be located in its southwest. Therefore, MHO 2116 and MHO 2117 may have some connections as suggested by Gómez et al. (2003).

• MHO 2118: MHO 2118 consists of two faint knots MHO 2118a and MHO 2118b (Fig. A.14). Khanzadyan et al. (2004) suggested YLW 16, the closest YSO, as the driving source. We obtained the proper motion of MHO 2118b, but it is uncertain because MHO 2118b has the low SNR in the first epoch image. Using the Owens Valley Millimeter Interferometer Terebey et al. (1989) detected a CO outflow driven by YLW 16. MHO 2118 is associated with the red-shifted lobe of this CO outflow. Therefore, we also suggest YLW 16 as the driving source of MHO 2118.

• MHO 2119: MHO 2119 shows a knot with a faint tail in Fig. A.14. Khanzadyan et al. (2004) detected this object and they suggested that MHO 2119 is related to MHO 2114. The PM vector of MHO 2119 points back to YLW 16. Terebey et al. (1989) detected an extended, blue shifted lobe north of YLW 16 in the direction of MHO 2119 (see Terebey et al. 1989, Fig. 2b). It seems that MHO 2119 and MHO 2118 constitute a bipolar outflow driven by YLW 16. Therefore, we suggest YLW 16 as the driving source of MHO 2119.

• MHO 2120: MHO 2120 is faint in Fig. A.14. Because there are many MHOs and YSOs in this region, Gómez et al. (2003) suggested several candidates for the driving source of MHO 2120, including YLW 15 and YLW 16. Based on the morphology and distribution of MHOs in this region Khanzadyan et al. (2004) inferred that MHO 2120 is part of a larger outflow driven by YLW 15. We obtained an uncertain proper motion measurement for MHO 2120 because of its low SNR in both epoch images. Nevertheless, the orientation of the PM vector indicates that the driving source of MHO 2120 should be locate to the south of MHO 2120. YLW 15 might have physical relations with MHO 2120.

• MHO 2121: MHO 2121 is an elongated knot in Fig. A.14. HH 674 is its optical counterpart (Gómez et al. 1998; Phelps & Barsony 2004). As there are many YSOs around HH 674, Phelps & Barsony (2004) did not offer any definitive identification of the driving source. Gómez et al. (2003) and Khanzadyan et al. (2004) both detected this object in their H₂ images. The latter suggested MHO 2121 being part of a bipolar H₂ outflow driven by YLW 16 (see Khanzadyan et al. 2004, Fig. 5). The PM vector of MHO 2121 indicates that the driving source should lie to the southwest of MHO 2121. There are many YSOs to the southwest that are located outside our images. Thus we cannot associate MHO 2121 with any ambient YSO.

• MHO 2122: MHO 2122 is a central knot with a faint diffuse nebula in Fig. A.14. Based on the morphology and distribution of the MHOs in this region, Khanzadyan et al. (2004) suggested MHO 2122 to be part of a bipolar outflow driven by YLW 15 (see Khanzadyan et al. 2004, Fig. 5). The PM vector of MHO 2122 indicates the driving source to its north. Therefore, we suggest YLW 47, a Class II source identified by Evans et al. (2009), as the driving source of MHO 2122.

• MHO 2123: Fig. A.14 shows the region of MHO 2123, which consists of three features. MHO 2123a is an elongated knot, MHO 2123b is a faint nebula, and MHO 2123c is a knot. Gómez et al. (2003) detected MHO 2123a in their H₂ images and named it as [GSWC2003] 7c. Khanzadyan et al. (2004) detected four features in MHO 2123, including [KGS2004] f04-05h, which is too faint to confirm in our H₂ images. Based on our reprocessing of Khanzadyan et al. (2004) data, which resulted in a non-detection of [KGS2004] f04-05h, we suspect that it might have been misclassified in the original analysis. Khanzadyan et al. (2004) suggested MHO 2123 as part of a bipolar H₂ outflow driven by YLW 16 (see Khanzadyan et al. 2004, Fig. 5). We obtained PM measurements for MHO 2123a,c. MHO 2123b have no enough SNR to measure the PM. The PM of MHO 2123a is uncertain due to its low SNR in the first epoch images. Our PM measurement for MHO 2123c indicates that its driving source should lie to the northwest. We associate MHO 2123c with YLW 47, the closest YSO in this direction.

• MHO 2124: MHO 2124 consists of two bright nebular features with MHO 2124b being more diffuse than MHO 2124a (see Fig. A.14). Gómez et al. (2003) and Khanzadyan et al. (2004) both detected MHO 2124. Khanzadyan et al. (2004) proposed YLW 16 as the driving source. The PM vectors of MHO 2124 indicate that its driving source should be located to its southwest. MHO 2124 and MHO 2121 might be part of the same outflow. There are some YSOs to the west, lying outside our images. We cannot offer a definite identification of the driving source of MHO 2124.

• MHO 2125: MHO 2125 is an elongated knot (Fig. A.15). Based on the morphology of MHO 2125, which hints at a bow shock pointing towards SE or SW, Khanzadyan et al. (2004) suggested that MHO 2125 might arise from a NW-SE flow driven by YLW 15 or YLW 16. We obtained the PM measurement of MHO 2125, but it is uncertain because of the low SNR in the first epoch images. This uncertain PM vector points back to the direction of WLY 2-55, an X-ray source identified by Pillitteri et al. (2010). There is also a YSO, YLW 45, located ~1.4′ to the south of MHO 2125 (outside the boundary of Fig. A.15). Bontemps et al. (1996) detected a CO molecular outflow from YLW 45, and MHO 2125 is roughly associated with the red-shifted lobe of this CO outflow.

• MHO 2126: MHO 2126 is a bipolar outflow consisting of two knots MHO 2126a and b. Figure A.16 shows that MHO 2126 is close to [GY92] 344, a “Flat spectrum” source (Evans et al. 2009) with a bipolar nebular. Khanzadyan et al. (2004) suggested this edge-on disk system with a bipolar outflow might be the driving source for MHO 2126. Our PM measurements of MHO 2126 support this conclusion.

• MHO 2127: MHO 2127 is a bright knot in Fig. A.15. Khanzadyan et al. (2004) found that MHO 2127 is elongated with the semi-major axis pointing towards YLW 16 (see Fig. A.14). We did not obtain a PM measurement for MHO 2127 although it has a point-like structure and enough SNR in both epoch images, which means that the proper motion of MHO 2127 is very small. We note that MHO 2127 is also located to the northeast of YLW 45 (~4′ and outside the boundary of Fig. A.15) and that the red-shifted lobe of the CO outflow driven by YLW 45 (Bontemps et al. 1996) extends roughly in the direction of MHO 2127.

• MHO 2128: MHO 2128 is an extended bow-like structure in Fig. A.17. Figure A.18 shows the zoom-in image. Grosso et al. (2001) detected MHO 2128 in H₂ 2.12 μm. They suggested that MHO 2128 belongs to two different jets emanating from two Class I protostars YLW 15 (see Fig. A.14) and YLW 52. Khanzadyan et al. (2004) also detected MHO 2128, together with several H₂ features to the east of YLW 52 (see Khanzadyan et al. 2004, Fig. 8). They suggested all the features to be driven by YLW 52. Lucas et al. (2008) also detected MHO 2128 in the UKIRT H₂ images (named I in Fig. 19 of their paper). They suggested that MHO 2128 belongs to a large outflow connecting MHO 2128, MHO 2106, MHO 2105, and some other features outside the coverage of our SofI observations. We identified six knots in MHO 2128 and obtained their proper motions. MHO 2128a-f show the radial PMs (Fig. A.18), indicating that they arise from the same driving source. The PM vectors indicate an driving source to its east. The proper motion results agree with the suggestion from Khanzadyan et al. (2004) and contradict the suggestions of MHO 2128 being part of a large outflow driven by a source located to its west.

• MHO 2129: MHO 2129 is a knot in Fig. A.17, with a zoom-in shown in Fig. A.19. Note that Fig. A.19 emphasizes the identification of MHO 2129 with the inverted-gray-scale images. MHO 2129 corresponds to the identification of [KGS2004] f08-01b by Khanzadyan et al. (2004). They also identified other two features, [KGS2004] f08-01c and d, in the immediate vicinity of YLW 52. However, [KGS2004] f08-01c and d are invisible in our continuum-subtracted H₂ images. We suspect that these two features are the mis-identified noise points. We obtained the PM measurement for MHO 2129, but it is uncertain because of the low SNR in both epoch images. Given the location of MHO 2129, Khanzadyan et al. (2004) proposed YLW 52 as the driving source.

• MHO 2130: MHO 2130 consists of two features in Fig. A.17, with a zoom-in shown in Fig. A.20. Note that Fig. A.20 emphasizes the identification of MHO 2130 with the inverted-gray-scale images. MHO 2130a is an elongated knot and MHO 2130b is a faint nebula. Khanzadyan et al. (2004) suggested that MHO 2130 arises from the walls of a cavity, possibly excited by oblique shocks in an S-shape flow from YLW 52. MHO 2130b is too faint for a PM measurement, but the SNR of MHO 2130a is sufficiently high. We obtained the PM measurement for MHO 2130a and the PM vector indicates that the driving source should be located in the southwest of MHO 2130a. Here we accept the suggestion from Khanzadyan et al. (2004) that MHO 2130 is driven by YLW 52.

• MHO 2131: MHO 2131 is an elongated knot in Fig. A.17. MHO 2131 corresponds to the identification of [KGS2004] f08-01g by Khanzadyan et al. (2004). They also detected a feature near MHO 2131, named [KGS2004] f08-01h, but [KGS2004] f08-01h is too faint in our continuum-subtracted H₂ images to be confirmed. Khanzadyan et al. (2004) suggested YLW 52 as the driving source of MHO 2131 and our PM measurement for MHO 2131 support this conclusion. It seems that MHO 2128-2131 constitute an S-shape H₂ outflow from YLW 52.

• MHO 2132: MHO 2132 consists of three features in Fig. A.21. Stanke et al. (2006) detected the Class 0 source MMS 126, located right between MHO 2132b and c. MMS 126 drives a CO molecular outflow (Stanke et al. 2006) and MHO 2132 is well associated with this CO outflow. Therefore, Khanzadyan et al. (2004) suggested MMS 126 as the driving source of MHO 2132. Our PM measurements for MHO 2132 support this conclusion. Note that the PM of MHO 2132c is uncertain because of its low SNR in the first epoch images. Actually, MHO 2132 has a mid-infrared counterpart in the Spitzer/IRAC images (Zhang & Wang 2009) and MMS 126 is also visible in the IRAC and MIPS images. The outflow shows more extended and more obvious structures in the IRAC images, including a bipolar nebular around MMS 126 and the emission to the north of MHO 2132c and to the south of MHO 2132a (see Zhang & Wang 2009, Figs. 5 and 6).

• MHO 2137: Fig. A.3 shows the region of MHO 2137, with a zoom-in shown in Fig. A.22. Gómez et al. (2003) detected this object, but they did not identify a driving source for this outflow. The PM vectors determined by us indicate a bipolar outflow from the Class I source [GY92] 30 (Evans et al. 2009), which shows up as an infrared nebula in the Ks image.

• MHO 2149: MHO 2149 is a knot shown in Fig. A.2. It is newly discovered in our deep H₂ images. We note that YLW 31 is located to the south of MHO 2149, but YLW 31 drives a NE-SW H₂ outflow (see the description of MHO 2104) and it has been confirmed as a single star with a resolution of 0.25′′ (Costa et al. 2000; Barsony et al. 2003). Therefore, MHO 2149 is unlikely to be driven by YLW 31. Phelps & Barsony (2004) detected the candidate HH object O1a within about 10′′ of MHO 2149. They suggested a relation between O1 and HH 419, which is located ~3′ to the southwest of MHO 2149. Therefore, MHO 2149 and HH 419 may arise from the same outflow.

• MHO 2150: Fig. A.3 shows the region of MHO 2150, with a zoom-in shown in Fig. A.23. MHO 2150 consists of two features MHO 2150a, a bright knot with a diffuse tail, and MHO 2150b, a dumbbell-shape knot. Caratti o Garatti et al. (2006) firstly detected this object, naming the features as A and B, but this identification is not included in the SIMBAD database. We obtained the PMs of MHO 2150 and the PM vectors indicate that MHO 2150a and b constitute a bipolar outflow driven by the central source [EDJ2009] 807.

• MHO 2151: Fig. A.1 shows the region of MHO 2151. MHO 2151 is a new feature with no previous identification. We obtained the PM of MHO 2151 and the PM vector indicates that the driving source of MHO 2151 should be located to the east. There are two YSOs in the east of MHO 2151, GSS 32 and LFAM 3. Kamazaki et al. (2003) detected a NW-SE CO molecular outflow named as AS outflow (see Fig. 5 in Kamazaki et al. 2003) which is centered around LFAM 3. They suggested LFAM 3 as the driven source of the AS outflow because LFAM 3 is associated with the 6 cm radio continuum emission, which is considered to be an indicator of the active ionized jet, and with the 1.3 mm dust continuum source. However, we found that MHO 2151 is not associated with blue-shifted or red-shifted lobe of AS outflow, so it seems impossible that MHO 2151 is driven by LFAM 3. Therefore, here we associate MHO 2151 with the nearby YSO GSS 32 based on the alignment of the PM vector and GSS 32. We also can see some faint extended structures between MHO 2151 and MHO 2102 (driven by [EDJ2009] 800; see the description about MHO 2102), which may indicate some interactions between these two H₂ outflows.

• MHO 2152: Fig. A.24 shows the region of MHO 2152. MHO 2152 is a newly discovered feature with no previous identification. We obtained the PM of MHO 2152 and the PM vector indicates that the driving source of MHO 2152 should lie to the southwest. There are several YSOs in the southwest of MHO 2152. We have no sufficient evidence to associate MHO 2152 with one of them.

• MHO 2153: Fig. A.24 shows the region of MHO 2153. MHO 2153 is a newly discovered feature with no previous identification. We obtained the PM of MHO 2153 and the PM vector indicates that the driving source of MHO 2153 should lie to the southwest. There are several YSOs in the southwest of MHO 2153, including [GY92] 236 and [GY92] 239. Here we suggest [GY92] 239 as the likely driven source of MHO 2153 just because [GY92] 239 is the closest YSO to MHO 2153.

• MHO 2154: Fig. A.21 shows the region of MHO 2154, which is a faint nebula in our H₂ image. Zhang & Wang (2009) identified a mid-infrared counterpart in the IRAC images, named EGO 33 (see Zhang & Wang 2009, Figs. 5 and 6). They suggested YLW 58 as the driving source of EGO 33 based on that MMS 126 has a close association with the known outflow detected in the near-infrared and in CO (3–2) emission (Stanke et al. 2006). They argued that EGO 33 is unlikely to be associated with MMS 126 as EGO 33 does not coincide with the axis of the known CO outflow. MHO 2154 is invisible in the first epoch images, thus we could not obtain its proper motion. Here we accept the suggestion from Zhang & Wang (2009) that YLW 58 is the driving source of MHO 2154.

• MHO 2155: MHO 2155 shows a elongated knot in Fig. A.13. MHO 2155 is a newly discovered feature with no previous identification. We did not get the PM measurement for MHO 2155 because it is invisible in the first epoch images. It seems that there are some faint structures between MHO 2155 and MHO 2117 in the H₂ narrowband image, which indicates that there may be some physical connections between MHO 2155 and MHO 2117.

Fig. A.1 Region of MHO 2102 and MHO 2151. Top-left: the H2 image with MHOs and YSOs labeled; top-right: the Ks image for the same region; bottom-left: the continuum-subtracted H2 image with MHOs labeled; bottom-right: the H2 image with the PMs marked. The YSOs from Evans et al. (2009) are marked with white or black circles and the X-ray sources from Pillitteri et al. (2010) are labeled with red crosses. The positions of the sub-millimeter sources from Johnstone et al. (2000) are marked with green filled diamonds and the positions of the millimeter sources from Young et al. (2006) with blue filled squares. The PM vectors of MHOs are shown with arrows and the dashed lines show the errors of PA. The black arrows represent reliable PMs and the red arrows represent uncertain PMs. Source designations used are as follows: [EDJ2009] is from Evans et al. (2009), [GY92] is from Greene & Young (1992b), GSS is from Grasdalen et al. (1973), LFAM is from Leous et al. (1991), YLW is from Young et al. (1986b), BBRCG is from Barsony et al. (1989), WLY is from Wilking et al. (1989), WSB is from Wilking et al. (1987), WL is from Wilking & Lada (1983), and EM*SR is from Struve & Rudkjøbing (1949).

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	Fig. A.2 Region of MHO 2103-2104 and MHO 2149. Top: the H2 2.12 μm image with MHOs and YSOs labeled; bottom: the continuum-subtracted H2 image with MHOs labeled. Others are the same as Fig. A.1. Note that there are no PM measurements for MHO 2103-2104 and MHO 2149 due to the lack of epoch1 imaging.
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	Fig. A.3 Large view of the region of VLA 1623. The background is the H2 2.12 μm image. Red boxes I–V are zoomed in following figures: Figs. A.4–A.23. The MHOs in this region are marked with red triangles and the YSOs are labeled with pink circles. Others are the same as Fig. A.1.
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	Fig. A.4 Zoom-in view of box I in Fig. A.3. Others are the same as Fig. A.1.
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	Fig. A.5 Zoom-in view of box III in Fig. A.3. Others are the same as Fig. A.1.
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	Fig. A.6 Zoom-in view of box IV in Fig. A.3. Others are the same as Fig. A.1.
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Fig. A.7 Region of MHO 2106. Top-left shows the H2 image with MHOs and YSOs being labeled and bottom-left shows the continuum-subtracted H2 image with the identifications of MHOs and YSOs. Top-right shows proper motions of the features of MHO 2106 on the H2 2.12 μm image. Bottom-right is a zoom-in view of the box in the top-right panel to emphasize the bright features in MHO 2106. Others are the same as Fig. A.1.

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	Fig. A.8 Same as Fig. A.1, but for the region of MHO 2108 and MHO 2109.
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	Fig. A.9 Same as Fig. A.1, but for the region of MHO 2110.
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	Fig. A.10 Same as Fig. A.1, but for the region of MHO 2111.
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	Fig. A.11 Same as Fig. A.1, but for the region of MHO 2112-2114.
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	Fig. A.12 Same as Fig. A.1, but for the region of MHO 2115.
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	Fig. A.13 Same as Fig. A.1, but for the region of MHO 2116 and MHO 2117.
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	Fig. A.14 Same as Fig. A.1, but for the region of MHO 2118-2124.
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	Fig. A.15 Same as Fig. A.1, but for the region of MHO 2125 and MHO 2127.
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	Fig. A.16 Same as Fig. A.1, but for the region of MHO 2126.
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	Fig. A.17 Same as Fig. A.1, but for the region of MHO 2128-2131.
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	Fig. A.18 Same as Fig. A.1, but for the region of MHO 2128.
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	Fig. A.19 Same as Fig. A.1, but for the region of MHO 2129. Note that backgrounds in the four panels are inverted gray scale images in order to enhance the H2 feature that is marked with white triangle.
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	Fig. A.20 Same as Fig. A.1, but for the region of MHO 2130. Note that backgrounds in the four panels are inverted gray scale images in order to enhance the H2 features that are marked with white circles.
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	Fig. A.21 Same as Fig. A.1, but for the region of MHO 2132 and MHO 2154.
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	Fig. A.22 Region of MHO 2137 and zoom-in view of box V in Fig. A.3. The top panel shows the H2 image with MHOs, YSOs, and PMs of MHO features being marked. The bottom-left panel shows the Ks continuum image and the bottom-right panel shows the continuum-subtracted H2 image with MHO features being marked. Others are the same as Fig. A.1.
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	Fig. A.23 Same as Fig. A.22, but for the region of MHO 2150 and box II in Fig. A.3.
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	Fig. A.24 Same as Fig. A.1, but for the region of MHO 2152 and MHO 2153.
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© ESO, 2013