The influence of upstream conditions on heavy ion escape at Mars

We apply a recently presented method to estimate ion escape to Mars. The method combines in-situ observations and a hybrid plasma model (ions as particles, electrons as a fluid). Observed upstream solar wind conditions from the Mars Atmosphere and Volatile Evolution (MAVEN)  are used as input to the model.  We then vary ionospheric ion production until the solution fits the observed bow shock location.  With this method, we investigate how upstream conditions, including solar EUV, solar wind dynamic pressure, Interplanetary Magnetic Field (IMF) strength and cone angle, affect the heavy ions loss. The results indicate that the heavy ions escape rate is higher in high EUV and the tail flux is sensitive to EUV variety while the plume is not. The ion escape rate increases as solar wind dynamic pressure increases.