Coronal and Transition Region Structure in the RS Canum Venaticorum Binaries V711 Tauri, AR Lacertae, and II Pegasi. I. Data Analysis and Emission Measure Distributions

Citations Over TimeTop 10% of 1998 papers

Abstract

We present a study of the transition regions and coronae of the RS CVn binaries V711 Tau, AR Lac, and II Peg. Archival data from the Extreme Ultraviolet Explorer (EUV E), International Ultraviolet Explorer (IUE), Goddard High-Resolution Spectrograph (GHRS), and a variety of X-ray telescopes have been analyzed and modeled. Emission measure distributions have been determined for the transition region of each system. The upper transition region (6.1 \ log has been studied using line uxes T e \ 7.4) from the EUV E. Emission measure distributions for the lower transition region (3.8 \ log have T e \ 5.3) been found using emission-line uxes obtained with IUE and the GHRS. Electron densities of D1.6 ] 1011 and D5 ] 1011 cm~3 have been determined at log and log respectively, T e \ 7.0 T e \ 4.7 using the density-sensitive Fe XXI j128.7 and Si III] j1892 lines. The total pressure (gas ] turbulent) is smaller at the lower temperature, indicating that the high-and low-temperature material originates in physically unconnected regions. The emission measure distributions derived from the EUV E line spectra are compared with emission measures found from spectral ts to a variety of low-resolution X-ray spectra, including our reanalysis of archival EXOSAT spectra. Although the emission measure distribution is continuous, both types of analysis lead to two distinct peaks in the high-temperature emission measure distribution, suggesting that there may be two classes of structure in the upper transition region and corona, e.g., two families of loops.

Related Papers

• → Tracking attosecond electronic coherences using phase-manipulated extreme ultraviolet pulses(2020)134 cited
• → Strong-field effects induced in the extreme ultraviolet domain(2020)5 cited
• → Extreme ultraviolet continuum emission from laser-generated plasmas and applications to spectroscopy(1994)10 cited
• → The emission-line chart(1995)3 cited
• → UV line emission of symbiotic stars(1982)1 cited