Investigation of micro-flaring and secular and quasi-periodic variations in dMe flare stars. VI - Quasi-periodicities in Gliese 644 AB (V 1054 Oph) prior to a large X-ray flare

Details Investigation of micro-flaring and secular and quasi-periodic variations in dMe flare stars. VI - Quasi-periodicities in Gliese 644 AB (V 1054 Oph) prior to a large X-ray flare Investigation of micro-flaring and secular and quasi-periodic variations in dMe flare stars. VI - Quasi-periodicities in Gliese 644 AB (V 1054 Oph) prior to a large X-ray flare

Nov 1990

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1990a%26a...239..235a&link_type=abstract

Astronomy and Astrophysics (ISSN 0004-6361), vol. 239, no. 1-2, Nov. 1990, p. 235-242. Research supported by Department of Educa

Astronomy and Astrophysics

Astrophysics

10

Dwarf Stars, Flare Stars, M Stars, Secular Variations, Stellar Atmospheres, Stellar Flares, Chromosphere, Magnetohydrodynamic Waves, Seismology, Stellar Coronas, X Ray Sources, Stellar Atmospheres, Dme Flare Stars, Surface Activity, Stellar Coronae, Asteroseismology, Stellar Photometry

Scientific paper

We present results of a search for quasi-periodicities in Gliese 644 AB prior to the large X-ray flare of 24/25, August 1985. Eight datasets of U-band monitoring lasting a total of 1.4 hours are analysed. One minor flare is reported. A small number of frequencies, some recurring from one dataset to another, are found to describe the optical variations quite well. A degree of phase coherence of waves over 45 min may exist in an 8.99-second signal in the data, and a wave maximum may occur at the instant when our minor flare reached peak light. Results are discussed in the context of the Ionson-Mullan model of resonating coronal cavities in dMe stars. Difficulty is encountered in accounting for the energy involved in the observed wave even for an electrodynamic-coupling efficiency of unity. We note, however, that the estimated dissipated power in the loop is closely similar to the total radiative losses in the chromosphere at the footpoints.

Affiliated with

Also associated with

No associations

Rating

Investigation of micro-flaring and secular and quasi-periodic variations in dMe flare stars. VI - Quasi-periodicities in Gliese 644 AB (V 1054 Oph) prior to a large X-ray flare does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Investigation of micro-flaring and secular and quasi-periodic variations in dMe flare stars. VI - Quasi-periodicities in Gliese 644 AB (V 1054 Oph) prior to a large X-ray flare, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Investigation of micro-flaring and secular and quasi-periodic variations in dMe flare stars. VI - Quasi-periodicities in Gliese 644 AB (V 1054 Oph) prior to a large X-ray flare will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-838702