Lewis M. Hobbs

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Spectra obtained with the Hubble Space Telescope GHRS are combined with highresolution optical spectra and UV spectra from Copernicus to study the abundances and physical conditions in the diffuse interstellar clouds seen along the line of sight to the star 23 Ori. Multiple absorption components are present for each of several distinct types of gas, which(More)
GHRS high resolution spectra of β Pictoris were obtained to study the stable gas around this star. Several elements are detected and their abundances measured. Upper limits to the abundances of others are also measured. The data permit improved chemical analysis of the stable gas around β Pictoris, and yield new and more accurate estimates of the radiation(More)
The ionization rate of interstellar material by cosmic rays has been a major source of controversy, with different estimates varying by three orders of magnitude. Observational constraints of this rate have all depended on analyzing the chemistry of various molecules that are produced following cosmic-ray ionization, and in many cases these analyses contain(More)
1. Stroke-prone spontaneously hypertensive rats (SHRSP) fed a high salt diet rapidly develop proteinuria, a marker of renal damage. We have recently shown that supplementing the diet of these rats with pure omega-3 fatty acids can inhibit the development of proteinuria. The aim of the present study was to examine the underlying renal pathology and to see(More)
Hydrogen peroxide, at concentrations comparable to those observed under some pathological conditions, produced a concentration-dependent inhibition of state 3 (ADP-stimulated) and uncoupled mitochondrial respiratory activity. The ADP:O ratio was also substantially reduced. In contrast, the organic peroxide, t-butylhydroperoxide at the same concentrations(More)
Echelle spectra of the double-lined spectroscopic binary HD 204827were obtained on five nights, at a resolving power R 1⁄4 38;000 and with a S/N 1⁄4 750 near 60008 in the final, combined spectrum. The stars show E(B V ) 1⁄4 1:11 and spectral types near O9.5 V and B0.5 III. A catalog is presented of 380 diffuse interstellar bands (DIBs) measured between 3900(More)
Using the new high-resolution (∼8 km s ) echelle spectrograph on the 3.5 m telescope at the Apache Point Observatory, we have begun a high-sensitivity survey of the diffuse interstellar bands (DIBs) in a large sample of reddened stars. Now that we are 2 years into this long-term survey, our sample includes over 20 reddened stars that show at least one of(More)
HD 44179 is the binary, post–asymptotic giant branch, central star of the Red Rectangle Nebula. Echelle spectra of the star have been obtained over a wavelength range from about 3800 to 10000 8 at a resolving power R 1⁄4 38; 000. A maximum S/N of 850 was achieved near 6800 8. Fifty-seven identified atomic or ionic emission lines of 12 elements are detected(More)
The proto-planetary Red Rectangle nebula is powered by HD 44179, a spectroscopic binary (P = 318 d), in which a luminous post-AGB component is the primary source of both luminosity and current mass loss. Here, we present the results of a seven-year, eight-orbit spectroscopic monitoring program of HD 44179, designed to uncover new information about the(More)
We present the results of exploratory HST observations to detect the emission lines of ions in the β Pictoris disk with the spectrograph slit placed off the star. Possible emission lines from Fe ii have been detected at ∼ 10−14erg cm−2 s−1 at 0.5′′ from β Pictoris, which would suggest a total Fe ii density of >∼ 2 · 10−2cm−3 at 10 AU. This detection needs(More)