HEAO 1 observations of X-ray emission from flares on dMe stars

Journal Article · Sat Dec 01 00:00:00 EST 1979 · Astrophys. J., Lett. Ed.; (United States)

DOI:https://doi.org/10.1086/183119· OSTI ID:5543481

Kahn, S M; Linsky, J L; Mason, K O; Haisch, B M; Bowyer, C S; White, N E; Pravdo, S H

We report the detection of two X-ray flares from each of the nearby dMe stars, AT Mic and AD Leo, with the A-2 experiment on board HEAO 1. A spectrum obtained during the brighter At Mic flare, the first X-ray spectrum of a stellar flare, is well matched by a thermal model with a temperature approx.3 x 10/sup 7/ K and an iron K..cap alpha.. emissiom line. The X-ray luminosities derived are in the range 1.3--16 x 10/sup 30/ ergs s/sup -1/, while emission measures are in the range 1.1--14 x 10/sup 53/ cm/sup -3/. The estimated L/sub z//L/sub opt/ ratios exceed unity and are inconsistent with Mullan's flare model. We propose several scenarious to explain this discrepancy.

• Research Organization: Space Sciences Laboratory, University of California, Berkeley
• OSTI ID: 5543481
• Journal Information: Astrophys. J., Lett. Ed.; (United States), Vol. 234:2
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
STELLAR FLARES
X-RAY SPECTRA
COSMIC X-RAY SOURCES
ELECTRON DENSITY
LUMINOSITY
PLASMA
COSMIC RAY SOURCES
OPTICAL PROPERTIES
PHYSICAL PROPERTIES
SPECTRA
640103* - Astrophysics & Cosmology- Quasi-Stellar
Radio
& X-Ray Sources- (-1987)