IUE observations of extragalactic objects

  title={IUE observations of extragalactic objects},
  author={Alec Boksenberg and M. A. J. Snijders and R. J. Wilson and Piero Benvenuti and Jordi Clavell and Ferdinando Duccio Macchetto and Michael V. Penston and Albert Boggess and Theodore R. Gull and Prabhakar Gondhalekar and Arthur Lonne Lane and Barry E. Turnrose and C. C. Wu and W. M. Burton and A M S Smith and Francesco Bertola and Massimo Capaccioli and Aina Elvius and Robert A. E. Fosbury and Massimo Tarenghi and M. H. Ulrich and R. L. Hackney and Carole Jordan and C. G. Perola and Robert Charles Roeder and M. R. Schmidt},
During the commissioning phase of IUE several extragalactic objects were observed spectrally at low dispersion in the UV range λλ1150–3200: the Seyfert galaxies NGC4151 and NGC1068, the QSO 3C273, the BL Lacertae object B2 1101 +38, the giant elliptical galaxy M87 and the spiral galaxy M81. The results obtained are presented and a preliminary analysis given for all six objects, discussing the continuous spectrum, extinction, emission line spectrum and absorption line spectrum, where possible… 

IUE observations of the interstellar medium

Results from a preliminary study of interstellar absorption lines in the spectra of the three stars HD149757, HD93521 and HD153919, observed by the IUE during its commissioning phase are presented.

Far UV observations of PKS2155–304

In BL Lac objects the absence of broad emission lines may be due either to a lack of ionizing continuum or to a lack of cool gas (T ≲ 104K)1. UV observations of BL Lac objects are interesting in that

Is the polarization of NGC1068 evidence for a non-thermal source?

NGC1068 is one of the brightest galaxies included by Seyfert1 in his list of extragalactic objects having compact, luminous nuclei within which broad, high-excitation emission lines occur. It has

The γ-ray emission from the Seyfert galaxy NGC 4151

  • L. Bassani
  • Physics
    Astrophysics and Space Science
  • 1981
Light curves at X-ray, ultraviolet, optical and infrared wavelengths of NGC 4151 over the period 1977–1980 are presented together with a summary of the large amount of observational data relating to

Space Telescope Imaging Spectrograph Echelle Observations of the Seyfert Galaxy NGC 4151: Physical Conditions in the Ultraviolet Absorbers

We have examined the physical conditions in intrinsic UV-absorbing gas in the Seyfert galaxy NGC 4151, using echelle spectra obtained with the Space Telescope Imaging Spectrograph (STIS) on the

Extragalactic Work with IUE

The International Ultraviolet Explorer (IUE) is an 18 inch (45 cm) space telescope for ultraviolet spectrophotometry in geosynchronous orbit and is a joint project of the European Space Agency, the

Space Telescope Imaging Spectrograph Echelle Observations of NGC 4151: Variable Ionization of the Intrinsic UV Absorbers

We present echelle observations of the intrinsic UV absorption lines in the Seyfert galaxy NGC 4151; these observations were obtained with the Space Telescope Imaging Spectrograph aboard the Hubble

Simultaneous Ultraviolet and X-Ray Observations of the Seyfert Galaxy NGC 4151. II. Physical Conditions in the UV Absorbers

We present a detailed analysis, including photoionization modeling, of the intrinsic absorption in the Seyfert 1 galaxy NGC 4151 using ultraviolet (UV) spectra from the Hubble Space Telescope Space

Infrared Spectroscopy of NGC 4151: Probing the Obscured Ionizing Active Galactic Nucleus Continuum

The Infrared Space Observatory (ISO) Short-Wavelength Spectrometer (SWS) infrared spectroscopic observations of the nucleus of Seyfert galaxy NGC 4151, which are described in a companion paper, are



Ultraviolet observations and the extended spectrum of NGC 4151.

Five-channel ultraviolet photometry of the Seyfert galaxy NGC 4151 was obtained at three epochs with the ANS. These data are combined with other recent results to illustrate the spectrum of the

IUE observations of hot stars: HZ43, BD + 75°325, NGC6826, SS Cygni, η Carinae

During the commissioning phase of IUE observations were made of a selection of hot stars: the white dwarf HZ43, the hot subdwarf BD + 75°325, the nucleus of the planetary nebula NGC6826, the dwarf

Ultraviolet spectrum of quasi–stellar object 3C273

The first direct observation of the ultraviolet spectrum of a quasi-stellar object (QSO) has been made with a rocket-borne telescope. The emission line spectrum of 3C273 is similar to the spectra of

The Distance of BL Lacertae

Spectrophotometric observations of the extended object around BL Lacertae have been conducted from August 1969 to October 1973 using circular apertures of various diameters as well as an annular

Low energy γ-ray observation of NGC4151

OBSERVATIONS of the Seyfert galaxy NGC4151 by Ariel V, OSOI VII and UCSD (refs 1–3 respectively) have demonstrated that it has a relatively flat X-ray spectrum up to photon energies greater than 100

The variability and absorption of the X-ray emission from NGC 4151.

The X-ray source 3U 1207+39, associated with the Seyfert galaxy NGC 4151, was observed for two days in 1974 November and again for six days in 1976 January by the University College London

The Continuous Optical Spectra of Active Nuclei

The optical continuum properties of the nuclei of radio galaxies, Seyfert galaxies, N systems, BL Lac Objects, and QSOs are reviewed. The observations are in the main consistent with the hypothesis

The spectrum of the Seyfert galaxy NGC 3516.

The Seyfert galaxy NGC 3516 was observed during 1975 using a digital image detector. Accurate measurements of emission-line intensities and profiles are presented. The narrow lines are emitted in a

Search for periodicities in the light variations of the Seyfert galaxy NGC 4151

The optical luminosity variations of the nucleus of the Seyfert galaxy NGC 4151 are examined. Power spectrum analysis is performed on heretofore unpublished photographic photometry as well as on the

The Physics of QSO Absorption Line Regions

The physical properties of the absorption systems observed in high redshift QSOs are described in some detail. Apart from the very broad absorption lines seen in a few objects, which almost certainly