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Dynamical activity in V1016 Cygni.
Feibelman, W. A.; Fahey, R. P.
New high-dispersion IUE observations show the C IV emission lines in V1016 Cyg to be split, suggesting evidence for dynamical activity. The [Mg V] line shows structure nearly identical to the C IV lines when plotted in velocity space.
The Final Cos-B Database: In-Flight Calibration of Instrumental Parameters
Strong, A. W.; Hermsen, W.; Lebrun, F. +3 more
A method for the determination of temporal variation of sensitivity is designed to find a set of parameters which lead to maximum consistency between the intensities derived from different observation periods. This method is briefly described and the resulting sensitivity and background variations presented.
Epsilon Aurigae
Chapman, R. D.
In April 1984, fourth contact ended the two year long eclipse of Epsilon Aurigae. An astrometric study of the study of the system was carried out by Van de Kamp (1978) leading to the conclusion that the orbit is seen very close to edge on. The eclipse was monitored by a number of groups from the ground and from spacecraft such as the IUE. Ultravio…
H0323+022 - Classification as a Bl-Lacertae and EXOSAT Coordinated Observations
McHardy, I.; McClintock, J. E.; Remillard, R. +18 more
The object H0323+022 (Doxsey et al. 1983) has been shown to be a BL Lac object by virtue of a diversity of observational characteristics at radio, optical, and x-ray wavelengths, in agreement with the conclusion of Margon and Jacoby (1984). Multi-frequency coordinated observations of this highly variable object with EXOSAT in September 1984 found …
Coordinated EXOSAT and Optical Observations of the X-Ray Burster 4U1737-44
Charles, P. A.; Corbet, R. H. D.; Smale, A. P. +2 more
We present the first results of an EXOSAT observation of the low-mass X-ray burster 4U1735-44. The ME data show low-amplitude variations in the persistent flux including two 5% dips separated by ∼4 hours. The structure of the single observed burst is briefly described. Five hours of simultaneous B-band photometry were obtained at SAAO with 12 minu…
EXOSAT spectra of some bright QSO's
Tennant, A. F.; Stewart, G. C.; Shafer, R. A. +1 more
This paper reports on EXOSAT observations of four bright QSO's and active galaxies. The QSO PHL 1657 has a simple spectrum that can be fit with power law plus some low energy absorption. A soft excess is observed for both MR 2251 and E 1352.24+1830. Finally, PKS 2126-158 was detected and the results are consistent with a 0.7 energy index.
The Quiescent Spectrum of 2S1636-536
King, A.; Turner, M. J. L.; Breedon, L. M. +1 more
During the EXOSAT observation of 2S1636-536 in July 1983 the quiescent flux was observed to brighten from 1.7×10 -9 ergs/cm. 2 /sec to 2.6×10-9 ergs/cm. 2 /sec, this increase being accompanied by a decrease in effective temperature. Further analysis of the spectrum reveals that the best fit is a power …
The Golactic Gamma-Ray Distribution and the Radial Cosmic Ray Gradient
Harding, A. K.; Stecker, F. W.
The authors have derived the radial distribution of gamma-ray emissivity and the cosmic ray intensity in the Galaxy using the final SAS-2 results, the recently corrected COS-B results, and recent CO surveys of the northern and southern galactic hemispheres. In addition to the "5 kpc ring" of enhanced emission, there is evidence for spiral features…
Inverse-Compton Gamma Rays in the Galaxy
Bloemen, J. B. G. M.
Compton gamma rays with energies 1 MeV largely results from scattering between electrons, with energies 100 MeV, and photons in the optical and infrared range and the 2.7 K universal blackbody radiation. An empirical model of the inverse Compton (IC) gamma ray production in the Galaxy is presented, using the most recent estimate of the interstella…
EXOSAT observation of the QSO galaxy pair 1E0104.2+3153
Giommi, P.; Maccacaro, T.; Gioia, I. M.
A very long (160,000 second) observation of the X-ray source 1E0104.2+3153 was carried out using the Channel Multiplier Array (CMA) instrument on board Exosat in August 17, 1984. A thin Lexan filter having maximum throughput in the 0.05-2.0 keV CMA band was used during the entire observation period. The positional accuracy of the CMA was sufficien…