THE STUDY OF THE SPATIAL CONFIGURATION OF THE MAGNETIC FIELD IN ACTIVE REGIONS (Inferred by Vector Magnetograms and Yohkoh X-ray data)

ar098.zhang_hongqi01
Posted:  16-Dec-96
Updated:
Events specified: AR 7562 (Aug-93)


Hongqi Zhang* and Solar Group of NAOJ

(* Beijing Astronomical Observatory, China and visiting astronomer at NAOJ)


Special note to your proposal: As you already know, this proposal has a overlap with the subject being studied by Mr. Morita (a student of Prof. Uchida). Although there is no formal restriction for you proposal, DUC would appreciate it if you closely communicate him.

The study of the magnetic field in solar active regions is a very important project, which relates to the emergence of new magnetic flux, evolution and the reconnection of the magnetic lines of force in solar active regions. Hongqi Zhang works at the Huairou solar group of Beijing Observatory. The photospheric and chromospheric magnetograms supply important boundary conditions of 3-D magnetic field on solar active regions. A series of photospheric vector magnetograms and chromospheric magnetograms was obtained at Huairou, and also at National Astronomical Observatory of Japan. H.Q. Zhang and his collaborators (Drs. T. Sakurai and K. Shibata) at NAOJ studied on the vector magnetograms and vertical electric current inferred by the transverse magnetic field for a long time. The photospheric and chromospheric magnetograms supply important boundary conditions of 3-D magnetic field on solar active regions.

Yohkoh satellite provides a chance to study the possible configuration of the magnetic field above the chromosphere, which information comes from the Yohkoh X-ray images.

We will pay attention to study the possible 3-D configuration of the magnetic fields and the possible relationship with the flares in active region NOAA 7070. This active region, occurred in February 1992, was a powerful flare-producing region. Some flares occurred near center of the solar disk and limb. We can analyze the changes of flare loops with the magnetic field.

We also will study a new emerging flux region NOAA 7562 in August 1993. A observing campaign at the study of emerging flux regions was conducted among several observatories around the world (Tenerife, La Palma, Huairou, Hawaii, Big Bear, Kitt Peak, and Japanese observatories), in cooperation with Yohkoh satellite.