A Catalogue of 0.2 Å Resolution Far-Ultraviolet Stellar Spectra Measured with Copernicus [chapter]

Theodore P. Snow, Edward B. Jenkins
1977 Highlights of Astronomy  
Of the nearly 300 stars which have been observed in the ultraviolet with Copernicus, 60 have been chosen for publication of their complete intermediate-resolution spectra, which consist of scans made with photomultiplier U2 at a nominal resolution and step length of 0.2 A. The spectra cover the wavelength range 1000 to 1^+50 A and are expressed in the form of direct numerical tabulations, compressedscale plots, and synthetic photographic spectrograms. These three modes of presentation are
more » ... sentation are expected to satisfy the needs of various types of research on stellar spectra, ranging from detailed and rather specialized analyses of line profiles, which require accurate numerical results, to broad, comparative studies of various qualitative features over different spectral types, for which the plots or photographs are best suited. From the qualitative comparisons one might expect to synthesize more exacting criteria for spectral classifications of normal stars, using ultraviolet instead of visible spectra. The catalogue has been submitted for publication in the Astrophysical Journal Supplements . The 60 stars included in the catalogue were chosen to give maximum coverage in the H R diagram, and they represent a good distribution of luminosity classes among spectral types OU to Al. Wolf-Rayet stars, Be and shell stars, and other known peculiar objects were avoided, since the primary purpose of the catalogue is to present data on normal stars for a variety of temperatures and luminosities. All of the data have been corrected for background and stray light contamination, and are generally of good quality, although minor flaws may still be present. The numerical tables include an indication of the number of repeated scans averaged together at each wavelength, so that the noise amplitude due to photon statistics may be estimated directly. In the synthetic photographic spectrograms a granularity proportional to the relative noise amplitude is superposed. This granularity mimics the noise seen in ordinary photographic spectra of faint objects without
doi:10.1007/978-94-010-1250-8_69 fatcat:yulksq72dfhr3ey6ss6fstuoc4