The inversion of the real kinematic properties of coronal mass ejections by forward modeling

Kinematic properties of coronal mass ejections (CMEs) suffer from projection effects, and it is expected that the real velocity should be larger and the real angular width should be smaller than the apparent values. Several attempts have been taken to correct the projection effects, which however led to an inflated average velocity probably due to the biased choice of CME events. In order to estimate the overall influence of the projection effects on the kinematic properties of the CMEs, we perform a forward modeling of real distributions of CME properties, such as the velocity, the angular width, and the latitude, by requiring their projected distributions to best match observations. Such a matching is conducted by Monte Carlo simulations. According to the derived real distributions, we found that (1) the average real velocity of all non-full-halo CMEs is about 514 km s(-1), and the average real angular width is about 33 degrees, in contrast to the corresponding apparent values of 418 km s(-1) land 42.7 degrees in observations; (2) For the CMEs with the angular width in the range of 20 degrees - 120 degrees, the average real velocity is 510 km s(-1) land the average real angular width is 43.4 degrees, in contrast to the corresponding apparent values of 392 km s(-1) land 52 degrees in observations.