8 papers
STIS Spectroscopy of PKS 0405-123
G. Williger, S. Heap, R. Weymann +2
We present results for QSO PKS 0405-123 (z=0.574, V=14.9), as part of a STIS Investigation Definition Team (IDT) key project to study weak Ly-alpha forest systems at low z. We dete…
HST/STIS Spectroscopy of 3C 273
S. R. Heap, G. M. Williger, R. Dave +3
We present preliminary results on the low-redshift Lyman alpha forest as based on STIS spectra of 3C 273. A total of 121 intergalactic Lyman alpha-absorbing systems were detected,…
The Metallicity of the Local IGM from the HST/STIS Spectrum of 3C273
Romeel Davé, S. R. Heap, G. M. Williger +3
We present a preliminary study of the metallicity of low-redshift Lyman alpha absorbers from the HST/STIS spectrum of 3C273. Using a pixel-based shift-and-coadd technique, we compa…
Low Redshift Lyman Alpha absorbers and their Connection with Galaxies
Simon L. Morris, Buell Jannuzi, Ray Weymann
We review the ongoing debate about the relationship between low redshift Lyman Alpha absorbers and luminous galaxies. In particular, we discuss the difficulty of `assigning' a part…
AB Dor in '94: I. HST/GHRS Observations of the Quiescent Chromosphere of an Active Star
J. C. Brandt, S. R. Heap, F. M. Walter +15
We analyze HST/GHRS spectra of AB Doradus, the prototypical ultra-rapidly rotating K dwarf. We observed chromospheric (Mg II) and transition region (C II, Si IV, C IV, and N V) lin…
NICMOS Observations of the Hubble Deep Field: Observations, Data Reduction, and Galaxy Photometry
Rodger I. Thompson, Lisa J. Storrie-Lombardi, Ray J. Weymann +4
This paper contains a catlog of sources observed in a portion of the Hubble Deep Field by the NICMOS instrument. Methods of observation and data analysis are discussed. The catalog…