True versus apparent shapes of bow shocks

摘要: Astrophysical bow shocks are a common result of the interaction between two supersonic plasma flows, such as winds or jets from stars active galaxies, streams due to relative motion star and interstellar medium. For cylindrically symmetric shocks, we develop general theory for effects inclination angle on apparent shape. We propose new two-dimensional classification scheme shapes, which is based dimensionless geometric ratios that can be estimated observational images. The related flatness bow's apex, term planitude openness its wings, alatude. calculate expected distribution in planitude-alatude plane variety simple geometrical physical models: quadrics revolution, wilkinoids, cantoids, ancantoids. further test our methods against numerical magnetohydrodynamical simulations stellar find alatude measured infrared dust continuum maps serve accurate diagnostics shape contact discontinuity, used discriminate different models. present an algorithm determine observed shock emission with precision 10 20%.