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Simultaneous X-Ray and Infrared Observations of Cygnus X-3
White, N. E.; Mason, K. O.; Cordova, F. A.
Cygnus X-3 has been observed simultaneously in the X-ray and infrared spectral bands. A series of short flares were detected in the infrared. The most intense of these involve a doubling of the 2.2 micron flux. No counterparts of the flares were unequivocably detected in the X-ray band; the ratio of the flare energy emitted in the 1.5-10.0 keV and…
The Evolution of the 1984 Outburst of the Transient X-Ray Source 4U 1630-47
Stella, L.; Parmar, A. N.; White, N. E.
The results of a series of EXOSAT observations of the X-ray transient 4U 1630 - 47 during an outburst in 1984 are presented. The source decayed over an interval of about 100 days from a maximum 1-50 keV luminosity of about 2.8 x 10 to the 38th to about 4 x 10 to the 36th erg/s (for an assumed distance of 10 kpc). The 1-50 keV spectrum was best rep…
Observation of the Onset of an Emission Episode in the Be Star MU Centauri
Peters, G. J.
A series of recent CCD observations which shows the rapid development of Hα emission in the pulsating, transient Be star µ Cen in only 2 days and thus establishes a time scale for the physical changes in the photosphere that lead to the outburst, are presented. On 1985 March 25, Hα was in pure absorption in µ Cen but by 1985 March 27 a…
A 6 Second Periodic X-Ray Source in Carina
Charles, P. A.; Smale, A. P.; Seward, F. D.
A serendipitous source, 1E 1048.1-5937, was discovered during Einstein imaging observations of the Carina nebula. On July 13, 1979, this source had an intensity of 0.14 IPC counts/s, and the signal was 65 percent pulsed with a period of 6.44 s. An earlier observation failed to detect any source with strength greater than 1/10 the above signal. The…
The Ultraviolet Excess of Quasars. III. The Highly Polarized Quasars PKS 0736+017 and PKS 1510-089
Malkan, M. A.; Moore, R. L.
Ultraviolet/optical/infrared spectrophotometry of the highly-polarized quasars (HPQ's) PKS 0736 + 047 and PKS 1510 089 is analyzed. A blazer continuum component like that in BL Lac objects (e.g. with violent variability, high polarization, and a steep power-law shape) contributes about half the visual light of 1510 - 089, and at least three-quarte…
Identification of two southern X-ray emitting cataclysmic variables.
Buckley, D. A. H.; Schwartz, D. A.; Tuohy, I. R. +2 more
The optical identification of two faint HEAO 1 X-ray sources with previously uncataloged cataclysmic variables is reported. The two cataclysmic variables, 1H 0542 - 407 and H0534 - 581, have average V magnitudes of about 15.7 and about 14.9, and have similar high excitation spectra with moderate to strong He II 4686 A emission. X-ray measurements …
Simultaneous EXOSAT and IUE Observations of Fairall 9: Short and Long-Term Variability
Piro, L.; Perola, G. C.; Boksenberg, A. +11 more
Simultaneous observations of the Seyfert I galaxy Fairall 9 (F9) were performed with Exosat and IUE during October 1983 and 1984. A decrease in the flux of the source by more than a factor of 2 was observed at all wavelengths between the two epochs. Furthermore, in the X-ray (0.05-10-keV) band, variability of the order of 50 percent on a time scal…
The Ionization Structure of Planetary Nebulae. VI. NGC 7662
Barker, T.
Spectrophotometric observations of emission-line intensities over the spectral range 1400 - 7200 Å have been made in five positions in the planetary nebula NGC 7662. The variation of the Balmer decrement with position in the nebula suggests that there may be internal dust. The O++ and Balmer continuum electron temperatures decrease with…
The Abundance of Gallium in B-Type Chemically Peculiar Stars
Sadakane, K.; Jugaku, J.; Takada-Hidai, M.
Quantitative analyses of the Ga abundances in 27 Hg-Mn stars, 11 Si (magnetic) stars, eight He-weak stars, and seven normal stars are made with the resonance lines of Ga II at 1414 A and Ga III at 1495 A in International Ultraviolet Explorer (IUE) spectra. The Ga overabundances are confirmed as a genuine anomaly in many peculiar stars. Only upper …
Ultraviolet and Infrared Observations of Stars with ``Quenched'' Chromospheres and the Nature of Mass Loss
Carpenter, K. G.; Stencel, R. E.; Hagen, W.
Previous observational evidence implies that the presence of Ca II emission, a chromospheric indicator, is correlated with the gas/dust ratio in the envelopes of red giant and supergiant stars. An attempt is made to determine whether this correlation can be generalized to all chromospheric activity indicators and the gas/dust ratio. New ultraviole…