DOI

https://doi.org/10.48717/35ea-c726

Project

ED050

Title

The gradual revival of synchrotron radiation from the massive binary WR1

Abstract

Several tens of binary systems made of massive stars are known to be particle accelerators, as confirmed by their synchrotron radio emission. Relativistic electrons are accelerated in the strong shocks produced by the collision of the their stellar winds. As a result, the synchrotron emission region is not associated to the stars themselves, but is rather located in between and can be resolved using VLBI techniques. Among these synchrotron emitters, WR125 is certainly one of the most promising targets both in terms of opportunity to learn about the behavior of these objects and in terms of power injected in the shock physics of the colliding wind (including particle acceleration and synchrotron emission). This target evolves on a 29 yr orbit, and is just emerging from its very recent periastron passage. Our intention is to start a monitoring of WR125 while its synchrotron emission is gradually escaping from the optically thick winds. We request two observations separated by a 8-12 months interval at 6 cm (to optimize angular resolution). The next opportunity is not expected before the beginning of the 2050's.