THE INTERPRETATION OF HARD X-RAY POLARIZATION MEASUREMENTS IN SOAR ,FLARES John Leachl Center for Space Science and Astrophysics

We review recent observations of polarization of moderately hard X-rays in solar flares and compare them with the predictions of recent detailed modeling of hard X-ray bremsstrahlung production by non-thermal electrons. We find that the recent advances in the complexity of the modeling lead to h substantially lower predicted polarizations than in earlier models and more i fully highlight now various parameters play a role in determining the polari. a i zation of the radiation field. The new predicted polarizations are comparable to those predicted by thermal modeling of solar flare hard X-ray production, and both are in agreement with the observations. In the light of these results, we propose new polarization observations with current generation