Using coordinated observations from instruments on the Advanced Composition Explorer (ACE), the Solar and Heliospheric Observatory (SOHO), and the Ramaty High Energy Solar Spectroscopic Imager (RHESSI), we have evaluated the energetics of two well‐observed flare/CME events on 21 April 2002 and 23 July 2002. For each event, we have estimated the energy contents (and the likely uncertainties) of (1) the coronal mass ejection, (2) the thermal plasma at the Sun, (3) the hard X‐ray producing accelerated electrons, (4) the gamma‐ray producing ions, and (5) the solar energetic particles. The results are assimilated and discussed relative to the probable amount of nonpotential magnetic energy available in a large active region.
