Accession Number:

ADA151111

Title:

A Program of Ground-Based Astronomy to Complement Einstein Observations.

Descriptive Note:

Annual scientific rept. 1 Oct 83-30 Sep 84,

Corporate Author:

COLUMBIA UNIV NEW YORK COLUMBIA ASTROPHYSICS LAB

Personal Author(s):

Report Date:

1984-11-30

Pagination or Media Count:

22.0

Abstract:

The objective of the funded research is the formulation and execution of ground-based astronomical observations and interpretive studies complementary to the X-ray data accumulated with the Einstein satellite, to be used in addressing a number of questions of current astrophysical interest. During the past year, the program focussed on two main topics the processes leading to high energy emission in the winds and coronae of late-type stars, and the structure and evolution of supernova remnants and the neutron stars they may contain. The stellar work encompasses the development of a complete, X-ray flux-limited sample of stars which, when combined with our complete, magnitude-limited optical sample will provide the best available description of the distribution of coronal activity in stars of spectral types F through M. A principal corollary of this work is the determination of the contribution of coronally active M-dwarfs to the diffuse X-ray background. Star cluster studies are combined with the survey work toward the goal of specifying the critical factors governing the production and evolution of magnetically dominated coronae in late-type stars. The supernova remnant work concentrates on the twin problems of the evidence for and frequency of neutron star formation in supernova explosions and the time development of the luminosity and size of the expanding supernova shock wave.

Subject Categories:

  • Astrophysics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE