Engineering topics
Publications and source records attributed to Deboer, K. S..
Ultraviolet spectra with 15 km/s resolution of bright stars were searched for FeII and MgII interstellar lines. Equivalent widths of absorption for 8 stars are presented and average line-of-sight densities n(FeII) = 4 x 10(-8) and n(MgII) = 2 x 10(-7)/cubic cm are calculated. This represents approximately n(H) = 0.03/cuib cm.
Seven blue horizontal branch stars in the field were observed and a few HB stars were isolated in globular clusters. Energy distributions are compared to assess possible differences and also used in comparison with model atmospheres. Observed energy distributions of HB stars in NGC 6397 are used to estimate the total number of HB stars which produced the integrated fluxes as observed by ANS. Preliminary results are given for colors of globular clusters observed in the Magellanic Clouds and for their extent, based on the Washburn IUE extraction.
Eighteen high dispersion International Ultraviolet Exploration spectra of 6 stars in the large magellanic cloud (LMC) 3 stars in the small magellanic cloud (SMC) and 2 foreground stars were studied. Fourteen spectra cover the wavelengths lambda 1150-2000 A and 4 cover lambda 1900-3200 A. All the Magellanic Cloud star spectra exhibit exceedingly strong interstellar absorption lines due to a wide range of ionization stages at galactic velocities and at velocities associated with the LMC or SMC. The analysis is restricted to the Milky Way absorption features. Toward the LMC stars, the strong interstellar lines have a positive velocity extension, which exceeds the extension recorded toward the SMC stars. The most straightforward interpretation of these velocity extensions is obtained by assuming that gas at large distances away from the plane of the galaxy participates in the rotation of the galaxy as found in the galactic disk.
The Washburn Extraction Routine for low dispersion IUE spectra was reviewed. The shape of the point spread function (PSF) in low dispersion spectra is sufficiently well described by a gaussian function. The PSF is in large and small aperture essentially identical and values of sigma are presented. Several advantages of the extraction routine are mentioned.