A numerical simulation of the W50-SS 433 system

We present results of numerical simulations performed to study the evolutio n and interaction of jets propagating inside of Supernova Remnants (SNRs). There are new observations which show this kind of jet/SNR interaction (Dub ner et al. 1998, Gaensler rt al. 1998). From our numerical simulations. we compute synchrotron emission maps, in order to directly compare the numeric al results with the radio maps. Our aim is to explain the strange morphologies some SNRs exhibit in the rad io-continuum, such as the case of SNR W 50 in which a shell is interacting with the jets from the SS 433 sourer. in recent radio images (at 328 and 14 65 MHz, Dubner et al. 1998). the SNR W 50 shows a helical structure in its Eastern lobe. Our numerical results are consistent with the radio-continuum observations, and reveal that a probable origin for the helical structure in the Eastern lobe of W 50, is the generation of incident and reflected secondary shock waves in the jet beam. Furthermore the simulations show that the cocoon gas is pushing out the SNR shell, filling up its interior, and increasing the expansion velocity of the shell.