Probably Aschwanden, Kosugi,  Hanaoka, Nishio, & Melrose (1999).  More specifically, the radio comes from the trap and the HXR from the precipitating—these are related to long and short temporal behaviors too. It itself shows two loops  interacting. But the small one is really small compared with the larger one.  Treat them as a point source function, and one large trap.