Large-Scale Active Coronal Phenomena in Yohkoh SXT Images
IV. Solar Wind Streams from Flaring Active Regions

Center for Astrophysics and Space Sciences, UCSD, La Jolla, CA 92093-0424, U.S.A. and SRON Utrecht, Sorbonnelaan 2, 3584 CA Utrecht, The Netherlands

Frantisek Fárník
Astronomical Institute of Czech Academy of Sciences, 25165 Ondrejov, Czech Republic

Hugh S. Hudson
Solar Physics Research Corporation, 4720 Calle Desecada, Tucson, AZ 85718, USA

Paul Hick
Center for Astrophysics and Space Sciences, UCSD, La Jolla, CA 92093-0424, USA

Abstract

We demonstrate limb events on the Sun in which growing flare loop systems are embedded in hot coronal structures looking in soft X-rays like fans of coronal rays. These structures are formed during the flare and extend high into the corona. We analyze one of these events, on 28–29 August 1992, which occurred in AR 7270 on the eastern limb, and interpret these fans of rays either as temporary multiple ministreamers or plume-like structures formed as a result of restructuring due to a CME. We suggest that this configuration reflects mass flow from the active region into interplanetary space. This suggestion is supported by synoptic maps of solar wind sources constructed from scintillation measurements which show a source of enhanced solar wind density at the position of AR 7270, which disappears when 5 days following the event are removed from the synoptic map data. We also check synoptic maps for two other active regions in which existence of these fan-like structures was indicated when the active regions crossed both the east and west limbs of the Sun, and both these regions appear to be sources of a density enhancement in the solar wind.



ISSN 0038-0938