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Particle Drifts for a Finite Scattering Rate

Jokipii, J. R.

The Hydrogen Lyman-Alpha Emission of Capella

Ayres, Thomas R.; Linsky, Jeffrey L.; Gayley, K. G. +1 more

We describe the hydrogen Ly-alpha emission of the spectroscopic binary Capella (G8 III + GO III) recorded at 0.1 A resolution by the International Ultraviolet Explorer. The overt changes in the composite line shape with orbital phase are controlled by the active GO III star and permit a dissection of the stellar components despite the obliteration…

Low-resolution spectra of the Io plasma torus 2 days after the Ulysses encounter

Rauer, H.; Thomas, N.; Jockers, K. +1 more

Low-resolution spectra of the Io plasma torus have been obtained on 10 and 11 February 1992 (2 days after the Ulysses encounter) using the 2 m telescope of the Bulgarian National Observatory. The spectra show the forbidden line emissions of S ⁺ (λλ 6716, 6731 Å) and S ²⁺ (λ 6312 Å). Measured intensities are compared with a Vo…

X-Ray Light Curves of Active Galactic Nuclei Are Phase Incoherent

Done, Chris; Krolik, Julian; Madejski, Grzegorz

We compute the Fourier phase spectra for the light curves of five low- luminosity active galactic nuclei observed by EXOSAT. There is no statistically significant phase coherence in any of them. This statement is equivalent, subject to a technical caveat, to a demonstration that their fluctuation statistics are Gaussian. Models in which the X-ray …

Cospin let observations of recurrent energetic particle events during the in-ecliptic phase of the Ulysses mission

Bame, S. J.; Sanderson, T. R.; Marsden, R. G. +1 more

The Ulysses spacecraft, launched in October 1990, traversed the in-ecliptic region of the heliosphere from 1 to 5 AU during the post-maximum phase of solar cycle 22 prior to its encounter with Jupiter in February 1992. In the period from launch up to mid-1991, particle events were dominated by the effects of large-scale transient structures in the…

A multi-frequency study of symbiotic stars - III. Simultaneous ultraviolet and optical observations of AX Persei.

Ivison, R. J.; Evans, A.; Bode, M. F. +2 more

The results of UV and optical monitoring of the classical symbiotic star AX Per are reported. The recent visual postoutburst light curve is used to estimate the size of the binary components in the AX Per system and to speculate on the cause of unusual ingress/egress profiles. A similar analysis using a phase plot of He II intensity is used to det…

Sounder stimulated D_n resonances in Jupiter's Io plasma torus

MacDowall, R. J.; Stone, R. G.; Fainberg, J. +2 more

On February 8, 1992, the Ulysses spacecraft passed through Jupiter's Io plasma torus, where rich spectra of narrow-band resonances were stimulated by the relaxation sounder of the Ulysses unified radio and plasma wave (URAP) instrument. Since the gyrofrequency f_g is comparable to the plasma frequency f_p in the Io torus, it wa…

Imaging and spectroscopy of Abell 63 (UU Sge).

Pottasch, S. R.; Walsh, J. R.; Walton, N. A.

UU Sge, the eclipsing binary central star of the low- surface-brightness planetary nebula (PN) Abell 63, has been observed spectroscopically in the visible throughout its 11.2 hour period and especially during the minimum. A determination of the spectral types of the components of the binary system has been made. The primary hot central star is an…

Anomalous proper motions in the Cygnus superbubble region.

Jordi, C.; Torra, J.; Comeron, F. +1 more

In an analysis of proper motions of O and B stars contained in the Input Catalogue for Hipparcos, we have found a clear deviation from the expected pattern of systematic motions which can be readily identified with the associations Cygnus OB1 and Cygnus OB9, located near the edge of the Cygnus Superbubble. The anomalous motions are directed outwar…

The Onset of Wolf-Rayet Wind Outflow and the Nature of the Hot Component in the Symbiotic Nova PU Vulpecula

Sion, Edward M.; Shore, Steven N.; Scheible, Maureen P. +1 more

We have analyzed temporal variations in the far ultraviolet He II (1640), Si IV (1393, 1402), and C IV (1548, 1550) line profiles in eight high dispersion, International Ultraviolet Explorer Short Wavelength Prime spectra of the symbiotic nova PU Vul by comparatively examining these profiles on a common velocity scale. We see clear evidence of the…