Charge-exchange X-Ray Signature in Laboratory Outflow Interaction with Neutrals

According to the principle of Euler similarity between laboratory and astrophysical plasmas, laboratory plasmas driven by high-power lasers have been used to simulate some aspects of astrophysical phenomena. And in doing so, they aid our understanding of shock heating, interaction structures, and the consequential evolution for astrophysical outflows within a short timescale (similar to ns). In this work, we experimentally investigated the mechanism of X-ray emission originating from a hot outflow (plasma) with a velocity of around 330 km s(-1), impinging on a cold medium. A hybrid model was set up to understand the high-resolution X-ray spectra taken at the interaction region and to deduce that charge exchange takes place in such a laboratory miniature of astrophysical outflow interacting with dense molecular clouds, as in the cases of HH 248 and Cap in M82, for example. Effects from targets with multiple electrons are also explored. A brief analysis has been performed for our laboratory analog and astrophysical objects by a dimensionless ratio of the length scale between X-ray-emitting and charge-exchange regions.