Short solar events with evidence of repetitive structures

Journal Article · Sat Aug 01 04:00:00 EDT 1987 · Astrophys. J.; (United States)

DOI:https://doi.org/10.1086/165479· OSTI ID:5966787

Desai, U D; Kouveliotou, C; Barat, C; Hurley, K; Niel, M

Several short (less than 40 s) solar hard X-ray events (greater than 100 keV) have been observed simultaneously with identical instruments on the Venera 11, 12, 13, and 14 and Prognoz 7 (Franco-Soviet Signe experiments) spacecraft. High time resolution (equal to or greater than 2 ms) data were stored in memory when a trigger occurred. The observations reported here were made by Prognoz 7 and V12 which were closer to the sun at the time and provided good statistics. Observations of modulation with a period of 1.6 s for the event on 1978 December 3 are presented. Also presented is evidence for fast time fluctuations from an event on 1979 November 6, observed with Venera 12, and another on 1981 September 6, observed with the Solar Maximum Hard X-Ray Burst Spectrometer. Power spectrum analysis, epoch folding, and Monte Carlo simulation to evaluate the statistical significance of persistent time delays between features. The results are discussed in light of the MHD model proposed by Zaitsev and Stepanov (1982) and Zaitsev, Stepanov, and Chernov (1984). 21 references.

• Research Organization: NASA, Goddard Space Flight Center, Greenbelt, MD; CNRS, Centre d'Etude Spatiale des Rayonnements, Toulouse, Fance
• OSTI ID: 5966787
• Journal Information: Astrophys. J.; (United States), Journal Name: Astrophys. J.; (United States) Vol. 319; ISSN ASJOA
• Country of Publication: United States
• Language: English

Related Subjects

640104* -- Astrophysics & Cosmology-- Solar Phenomena
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
FLUCTUATIONS
MATHEMATICS
PROGNOZ SATELLITES
SATELLITES
SOLAR ACTIVITY
SOLAR FLARES
SOLAR X-RAY BURSTS
SPACE VEHICLES
SPECTRA
TIME-SERIES ANALYSIS
VARIATIONS
VEHICLES
VENERA SPACE PROBES