On the Nature of the Non-Thermal Radio Source at the Center of the Orion Streamers

Alfonso Trejo, Luis F. Rodríguez


We present VLA continuum observations at 20 and 6 cm toward a non-thermal radio source located at the Streamers region in Orion. We compare 1991 archive observations with new ones taken by us in 2008. The radio source could be a young stellar source or an evolved object like a microquasar or even a jet from a radio galaxy. Our analysis shows that there is no evidence of changes in the flux densities between both epochs at a level higher than 10%. Also, we set an upper limit at a 3σ level of 23 mas year−1 for the proper motions. At the distance of Orion this implies an upper limit to the velocity in the plane of the sky of 45 km s−1. At 6 cm, we detect linearly polarized emission at a level of ~ 5%, while at 20 cm we do not detect this emission above a level of ~ 2%. We conclude that the non-thermal radio source most probably is a radio galaxy aligned by chance with the line of sight to the Streamers in Orion.


ISM: individual (Orion Streamers, HH 222); radiation mechanisms: non-thermal; radio continuum: ISM

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