Discovery of three x-ray luminous pre-main-sequence stars

Journal Article · Sat Aug 15 04:00:00 EDT 1981 · Astrophys. J., Lett. Ed.; (United States)

DOI:https://doi.org/10.1086/183618· OSTI ID:5960478

Feigelson, E D; Kriss, G A

Three X-ray sources found serendipitously in Einstein images of the Taurus-Auriga cloud complex were observed at the McGraw-Hill Observatory and are found to be associated with approx.12 mag stars with weak H..cap alpha.. emission. The stars lie on the edges of dark clouds and are spectroscopically similar to the least active emission-line pre-main-sequence stars. Although they lie well above the ZAMS in the H-R diagram, they do not exhibit ultraviolet excess, strong optical variability, or evidence for mass outflow/inflow characteristics of the more active T Tauri stars. Their only unusual property is high X-ray luminosity (approx.10/sup 30/ ergs s1). It is suggested that the X-ray emission from pre-main-sequence stars is not closely linked to the conditions giving rise to their unusual spectroscopic properties. The emission may instead represent an enhanced form of the coronal activity producing X-rays observed in late-type main-sequence stars.

• Research Organization: Massachusetts Institute of Technology, Department of Physics and Center for Space Research
• OSTI ID: 5960478
• Journal Information: Astrophys. J., Lett. Ed.; (United States), Journal Name: Astrophys. J., Lett. Ed.; (United States) Vol. 248:1; ISSN AJLEA
• Country of Publication: United States
• Language: English

Related Subjects

640103* -- Astrophysics & Cosmology-- Quasi-Stellar
Radio
& X-Ray Sources-- (-1987)
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
BALMER LINES
COSMIC RAY SOURCES
COSMIC X-RAY SOURCES
EMISSION
ERUPTIVE VARIABLE STARS
LUMINOSITY
OPTICAL PROPERTIES
PHYSICAL PROPERTIES
SPECTRA
STARS
T TAURI STARS
VARIABLE STARS
VISIBLE SPECTRA