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MERLIN radio detection of an interaction zone within a binary Orion proplyd system

M. F. Graham·J. Meaburn·S. T. Garrington·T. J. O'Brien·W. J. Henney·C. R. O'Dell
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Abstract

Presented here are high angular resolution MERLIN 5 GHz (6 cm) continuum observations of the binary proplyd system, LV 1 in the Orion nebula, which consists of proplyd 168--326SE and its binary proplyd companion 168--326NW (separation 0.4 arcsec). Accurate astrometric alignment allows a detailed comparison between these data and published HST PC Halpha and [Oiii] images. Thermal radio sources coincide with the two proplyds and originate in the ionized photoevaporating flows seen in the optical emission lines. Flow velocities of approx 50 km/s from the ionized proplyd surfaces and \geq 100 km/s from a possible micro-jet have been detected using the Manchester Echelle spectrometer. A third radio source is found to coincide with a region of extended, high excitation, optical line emission that lies between the binary proplyds 168--326SE/326NW . This is modelled as a bowshock due to the collision of the photoevaporating flows from the two proplyds. Both a thermal and a non-thermal origin for the radio emission in this collision zone are considered.

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M. F. Graham, J. Meaburn, S. T. Garrington, T. J. O'Brien, W. J. Henney, C. R. O'Dell. 2002-01-07. MERLIN radio detection of an interaction zone within a binary Orion proplyd system. https://doi.org/10.1086/339398

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