اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدA one-sided knot ejection at the core of the HH 111 outflow
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تأليف
L. Gomez
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We present an astrometry study of the radio source VLA 1 at the core of the HH 111 outflow using new data (2007) as well as archival observations (1992-1996). All data were taken at 3.6 cm with the Very Large Array in its most extended (A) configuration. The source VLA 1 has undergone a dramatic morphological change, showing a one-sided knot ejection in the 2007 epoch. We also report on the detection of a 3.6 cm compact continuum source (VLA 3) located at (-10.6,98.7) from VLA 1. No significant absolute proper motions were found for VLA 1 and VLA 3 and the upper limits are consistent with those found for (embedded) radio sources in the Orion Nebula. We favor the interpretation that in the continuum at 3.6 cm we are observing two nearly perpendicular jets. HH 111 presents a new case of one-sided jet ejection in a young stellar object. The Galactic (or extragalactic) nature of VLA 3 remains unclear.
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We present sensitive, high angular resolution ($0rlap.{}05$) VLA continuum observations made at 7 mm of the core of the HH 111/121 quadrupolar outflow. We estimate that at this wavelength the continuum emission is dominated by dust, although a signif
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. We study the molecular emission from the bipolar outflow powered by the very young stellar object HH 114 MMS and compare its chemical composition with that of the L1157 outflow. Methods. We have used the IRAM 30m radio telescope to observe a number of transitions from CO, SiO, CH3OH, SO, CS, HCN, and HCO+ toward the HH 114 MMS outflow. The observations consist of maps and a two-position molecular survey. Results. The HH 114 MMS outflow presents strong emission from a number of shock-tracer molecules that dominate the appearance of the maps around the central source. The abundance of these molecules is comparable to the abundance in L 1157. Conclusions. The outflow from HH 114 MMS is a spectacular new case of a chemically active outflow.
We present millimeter line observations of the HH 111 outflow and its driving source. The molecular gas emission observed with IRAM 30m and the CSO reveals a small condensation of cold and dense gas. The low-velocity outflow has been mapped with the
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