HST/FOS UV and WFPC II Observations of 3CR 196
Session 60 -- Intergalactic Medium
Display presentation, Thursday, 2, 1994, 9:20-6:30

## [60.01] HST/FOS UV and WFPC II Observations of 3CR 196

A. Diplas, R. D. Cohen, T. A. Barlow, E. A. Beaver, V. T. Junkkarinen, and R. W. Lyons (CASS/UCSD)

We present UV (FOS) and optical (WFPC II) observations of the z = 0.43685 absorption system in 3CR 196 ( z$_{em}$ = 0.8714, V = 17.79). The system is clearly seen in 21 cm. We obtained two sets of HST/FOS data at a resolution of $\simeq$ 200, using the low resolution grating G160L, with the large $4.3"$ aperture, and the $1.0"$ circular aperture, respectively. The wavelength coverage of the observations is from $1600$\AA\ to $2450$\AA\ . The region of the Ly$\alpha$\ line is seriously confused by a Lyman limit and strong, broad high-ionization lines from the z$_{a}$ $\simeq$ z$_{em}$ system. We conclude that a damped Ly$\alpha$\ line is present at z = 0.43685 with a best fit column density of N(H I) $\simeq$ 2$\times 10^{20}$ cm$^{-2}$. The minimum column density N(H I) required is 5$\times 10^{19}$ cm$^{-2}$.

We have recently obtained a Post-Costar WFPC II image of 3CR 196. We can clearly see a spiral galaxy located approximately 2" from the QSO, implying an impact parameter of $\simeq$ 8 kpc, assuming H$_0=75$\ and q$_0=0.5$

This work is part of Goddard High Resolution Spectrograph Guaranteed Time Observations and is supported by NASA grant No. NAG5-1858.