The Extreme Ultraviolet Explorer Stellar Spectral Atlas

Abstract

We present an atlas of extreme ultraviolet (EUV) spectra of 95 bright stellar sources observed between 1992 July and 1996 June with the Extreme Ultraviolet Explorer (EUV E) spectrometers. These data are taken in the short-(SW ; 70È190 medium-(MW ; 140È380 and long-wavelength bandpasses (LW ; A ), A ), 280È760 at roughly 0.5, 1, and 2 resolution, respectively. We describe the spectrometers and detail A ) A the procedure used to reduce the observational data to spectra. The atlas is grouped by the type of source : OÈA stars, FÈM stars, white dwarfs, and cataclysmic variables. We present a brief overview of the general nature and EUV spectral distribution of each group and present accompanying notes and individual spectra for each source. We show selected FÈM sources in more detail with identiÐcations of the brightest spectral lines illustrating the characteristics of the EUV spectra of stars of various temperatures. The current study is the most complete compilation to date of aggregate spectra of bright EUV stellar sources.

Spectroscopic observation of helium-ion- and hydrogen-catalyzed hydrino transitions

“…The mysteries of the identity of dark matter, the observed dark interstellar medium spectrum, the source of the diffuse X-ray background, and the source of ionization of the IGM [62,63] are resolved by the formation of hydrinos that emit · 13 6 eV emission, EUV and X-ray continua depending on the state transition and conditions, a 63.3 nm line [35][36][37][38], and pump the helium ion lines such as the 30.4 nm line. That the same transitions occur in stars [64] and the Sun as evident by corresponding continua and line emission in its spectrum resolves the solar corona problem, the cause of sunspots and other solar activity, and why the Sun emits X-rays [38].…”

Classification of EUV stellar sources detected by the ROSAT WFC

“…The difference among the two data sets could be due to the long-term variability caused by the presence of the WD. Finally, Craig et al (1997) classified the WD as metal-rich and the primary component as F5IV. However, we note that the latter classification gives a worse fit of the observed color than the F5V one.…”

Possible Overionization of C II, N II, and O II Ions in the Atmospheres of Early B- and Late O-Type Stars

“…It has come to be assumed that the very process that leads to overheating of the outer layers of the atmospheres of hot stars and to the appearance of the x-rays (e.g., shock waves in a stellar wind [16]) can greatly increase the hard radiation in the far ultraviolet (UV); it will be shown below that the latter plays an important role in the calculations Unfortunately, observations of stars in the region of the Lyman continuum (λ < 912 Å) are very difficult because of strong absorption by interstellar hydrogen. Nevertheless, the EUVE satellite, launched in 1992, has yielded the distribution of the flux for λ < 912 Å for two early B-stars, ε CMa (B2 II) and β CMa (B1 II-III) [17]. These stars happened to lie in a fairly transparent region of space, where the number of interstellar hydrogen atom absorbers is comparatively low, so it was easier to detect the UV flux.…”