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Faint Object Camera Imaging and Spectroscopy of NGC 4151
Boksenberg, A.; Barbieri, C.; Weigelt, G. +17 more
We describe ultraviolet and optical imaging and spectroscopy within the central few arcseconds of the Seyfert galaxy NGC 4151, obtained with the Faint Object Camera on the Hubble Space Telescope. A narrowband image including [O III] λ5007 shows a bright nucleus centered on a complex biconical structure having apparent opening angle ~65^deg^ and ax…
Ultraluminous Infrared Galaxies and the Radio-optical Correlation for Quasars
Lonsdale, Carol J.; Smith, Harding E.; Lonsdale, Colin J.
Through analysis of available optical spectrophotometric data and radio flux density measurements in the literature, it is demonstrated that a good correlation exists between the radio power and bolometric luminosity of the optically-selected QSOs in the Bright Quasar Sample (BQS) of Schmidt & Green (1983). This correlation, noted previously b…
Lithium Abundances in Strong Lithium K Giant Stars: LTE and Non-LTE Analyses
de La Reza, Ramiro; da Silva, Licio
Detailed non-Local Thermodynamic Equilibrium (non-LTE) and LTE analyses are made of two very strong Li K giants, HD 19745 and HD 39853, and of the strong Li K giant HD 787. The stronger star HD 19745 has recently been discovered to show very strong Li. These analyses are based on the observations done at European Southern Observatory (ESO) of the …
Reverberation Mapping by Regularized Linear Inversion
Krolik, Julian H.; Done, Christine
Reverberation mapping of active galactic nucleus emission-line regions requires the numerical deconvolution of two time series. We suggest the application of a new method, regularized linear inversion, to the solution of this problem. This method possesses many good features; it imposes no restrictions on the sign of the response function; it can …
He 3-1475 and Its Jets
Grebel, E. K.; Zijlstra, A. A.; Tinney, C. G. +5 more
We present spectra and high-resolution images taken with the Hubble Space Telescope (HST), the NTT, the VLA, and the MPIA/ESO 2.2 m telescope of the emission-line star He 3-1475, which we suggest is a postasymptotic giant branch star. The star is presumed to be at the origin of a 15" long structure containing symmetrically opposing bright knots. T…
Lensing by Distant Clusters: HST Observations of Weak Shear in the Field of 3C 324
Dickinson, Mark; Smail, Ian
We present the detection of weak gravitational lensing in the field of the radio galaxy 3C 324 (z = 1.206) using deep HST imaging. From an analysis of the shapes of faint R = 24.5--27.5 galaxies in the field we measure a weak, coherent distortion centered close to the radio source. This shear field most likely arises from gravitational lensing of …
Probing the Galactic Disk and Halo. III. The Galactic and Intergalactic Sight Line to H1821+643
Sembach, Kenneth R.; Savage, Blair D.; Lu, Limin
We present intermediate-resolution (FWHM ∼10-20 km s-1) GHRS observations of interstellar and intergalactic absorption lines in the spectrum of the bright quasar H1821+643. The interstellar species detected include S II, Si II, Mg II, C IV, and N V. The intergalactic lines include Lyα (six lines), Lyβ (2 lines), Lyγ, and C III. The Gala…
Discovery of an Optical Synchrotron Jet in 3C 78
Baum, Stefi A.; Sparks, William B.; Miley, George K. +5 more
We report the discovery of an optical synchrotron jet emanating from the nucleus of NGC 1218, the galaxy hosting the radio source 3C 78. The jet is similar to that of M87, although smaller in projected length. The observations were obtained as part of our Hubble Space Telescope "snapshot" program to acquire broadband images with high spatial resol…
UIT and Optical Imagery of Large Magellanic Cloud Associations LH 52 and LH 53: Ages and Initial Mass Function Slopes
O'Connell, Robert W.; Hill, Robert S.; Bohlin, Ralph C. +4 more
A 40' field including the stellar associations LH 52 and LH 53 and the supernova remnant N49 in the Large Magellanic Cloud was observed by the Ultraviolet Imaging Telescope (UIT) during the Astro-1 Space Shuttle mission in 1990 December. The image in the 162 nm bandpass is discussed together with ground-based BV data on subfields containing LH 52 …
Cataclysmic and Close Binaries in Star Clusters. III. Recovery of the Quiescent Nova 1860 a.d. (T Scorpii) in the Core of the Globular Cluster M80
Drissen, Laurent; Shara, Michael M.
Only two candidate classical nova eruptions have ever been seen in globular clusters. Only one, that of Nova 1860 (T Sco in M80), seems beyond any doubt a cluster member. We have obtained Hubble Space Telescope (HST) imagery of the central regions of M80 and find a very blue candidate within 1" of the astrometric position reported in 1860. Only on…