ASCA X-ray spectra of the active single stars β Ceti and π1 Ursae Majoris

Drake, S. A. ; Singh, K. P. ; White, N. E. ; Simon, Theodore (1994) ASCA X-ray spectra of the active single stars β Ceti and π1 Ursae Majoris The Astrophysical Journal, 436 (1). L87-L90. ISSN 0004-637X

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Official URL: http://articles.adsabs.harvard.edu/cgi-bin/nph-iar...

Related URL: http://dx.doi.org/10.1086/187639

Abstract

We present X-ray spectra obtained by ASCA of two single, active stars, the G dwarf π1 UMa, and the G9/K0 giant βCet. The spectra of both stars require the presence of at least two plasma components with different temperatures, 0.3-0.4 keV and ~0.7 keV, in order for acceptable fits to be obtained. The spectral resolving power and signal-to-noise ratio of the solid state imaging spectrometer (SIS) spectra allow us to formally constrain the coronal abundances of a number of elements. In β Cet, we find Mg to be overabundant, while other elements such as O, Ne, and N are underabundant, relative to the solar photospheric values. From the lower signal-to-noise ratio SIS spectrum of π1 UMa, we find evidence for underabundances of O, Ne, and Fe. These results are discussed in the context of the present understanding of elemental abundances in solar and stellar coronae.

Item Type:Article
Source:Copyright of this article belongs to American Astronomical Society.
Keywords:Abundance; Binary Stars; Dwarf Stars; Giant Stars; Stellar Composition; X Ray Spectra; Imaging Spectrometers; Signal to Noise Ratios; Stellar Coronas
ID Code:59026
Deposited On:03 Sep 2011 12:10
Last Modified:18 May 2016 09:44

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