Particle acceleration in flares     

A. O. Benz  T. Kosugi  M. J. Aschwanden  S. G. Benka  E. L. Chupp  S. Enome  H. Garcia  G. D. Holman  V. G. Kurt  T. Sakao  A. V. Stepanov  M. Volwerk 《Solar physics》1994,153(1-2):33-53

Particle acceleration is intrinsic to the primary energy release in the impulsive phase of solar flares, and we cannot understand flares without understanding acceleration. New observations in soft and hard X-rays, -rays and coherent radio emissions are presented, suggesting flare fragmentation in time and space. X-ray and radio measurements exhibit at least five different time scales in flares. In addition, some new observations of delayed acceleration signatures are also presented. The theory of acceleration by parallel electric fields is used to model the spectral shape and evolution of hard X-rays. The possibility of the appearance of double layers is further investigated.Report of Team 3, Flares 22 Workshop, Ottawa, May 25–28, 1993.  相似文献   

Energetics and Dynamics of an Impulsive Flare on March 10, 2001     

Ramesh Chandra  Rajmal Jain  Wahab Uddin  Keiji Yoshimura  Takeo Kosugi  Taro Sakao  Anita Joshi  M. R. Deshpande 《Solar physics》2006,239(1-2):239-256

We present Hα observations from ARIES (Nainital) of a compact and impulsive solar flare that occurred on March 10, 2001 and which was associated with a CME. We have also analyzed HXT, SXT/Yohkoh observations as well as radio observations from the Nobeyama Radio Observatory to derive the energetics and dynamics of this impulsive flare. We coalign the Hα, SXR, HXR, MW, and magnetogram images within the instrumental spatial-resolution limit. We detect a single HXR source in this flare, which is found spatially associated with one of the Hα bright kernels. The unusual feature of HXR and Hα sources, observed for the first time, is the rotation during the impulsive phase in a clockwise direction. We propose that the rotation may be due to asymmetric progress of the magnetic reconnection site or may be due to the change of the peak point of the electric field. In MW emission we found two sources. The main source is at the main flare site and another is in the southwest direction. It appears that the remote source is formed by the impact of accelerated energetic electrons from the main flare site. From the spatial correlation of multiwavelength images of the different sources, we conclude that this flare has a three-legged structure.  相似文献