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An explanation for the absence of sounder-stimulated gyroharmonic resonances in the Io plasma torus by the Ulysses relaxation sounder
Stone, R. G.; Fainberg, J.; Benson, R. F. +2 more
Plasma resonances were excited by the relaxation-sounder component of the unified radio and plasma wave instrument (URAP) during the Ulysses encounter with Jupiter's Io plasma torus. The observed resonant spectra were quite different than expected, based on earlier published observations from topside sounders in the terrestrial ionosphere and rela…
Ultraviolet interstellar linear polarization. IV. Cross-calibration between the Wisconsin ultraviolet photo-polarimeter experiment and the faint object spectrograph.
Martin, P. G.; Whittet, D. C. B.; Clayton, Geoffrey C. +6 more
The Wisconsin Ultraviolet Photo-Polarimeter Experiment (WUPPE) and the Faint Object Spectrograph (FOS) started gathering UV spectropolarimetry in 1990. Each observed a wide range of polarimetrically interesting objects before being retired. This paper examines the polarimetric calibration of each instrument and compares the absolute calibrations t…
The Ulysses north polar pass: Latitudinal gradients of anomalous cosmic ray O, N And Ne
Sanderson, T. R.; Marsden, R. G.; Trattner, K. J.
A key finding of the Ulysses mission has been the absence of large latitudinal gradients in the Anomalous Cosmic Ray (ACR) component. Studies using data from several satellites have consistently shown a small (∼ 2%/deg.) positive latitudinal gradient for anomalous O, N and Ne in the energy range 4 to 30 MeV/n, and even smaller gradients for ACR He…
A Reassessment of the IUE Emission Line Spectrum of the Planetary Nebula NGC 5189 and Its Central Star
Feibelman, W.
Archival high-and low-dispersion IUE spectra of NGC 5189 and its central star were reexamined. It was found that earlier published results misinterpreted nebular features for stellar emission lines due to incorrect coordinates and/or incorrect pointing of the spacecraft. NGC 5189 has a UV spectrum rich in emission lines of He II, C II], C III, C I…
Studies of Mira Stars and Their Small-Amplitude Relatives
Percy, John R.
Some aspects of the nature and evolution of Mira stars and their small-amplitude relatives are briefly described. As stars ascend the asymbiotic giant branch, it appears that they begin to pulsate when their effective temperature drops below 3800 K. The amplitude tends to increase with decreasing temperature. The stars show appreciable periodicity…
IUE and Voyager Observations of the Unusual Cataclysmic Variable S193
Garnavich, Peter; Szkody, Paula; Holberg, Jay +2 more
UV observations of S193 were obtained with Voyager and the IUE satellite during both high and low states of this unusual object. Voyager only detected the source during the high state, where the continuum looks similar to the novalike IX Vela and dwarf novae at outburst. The IUE spectra at the high state show deep absorption lines, but the line ra…
The Long-Term Periodic Oscillation of the NGC 4151 Nucleus
Lyuty, V. M.; Kotov, V. A.; Haneychuk, V. I. +3 more
The hypothesis that the luminosity of the nucleus of the Seyfert 1 galaxy NGC 4151 varies with a period of P0 ~ 160.0101 minutes is revised. In 1987-1994 a series of photometric observations of the NGC 4151 has been carried out in the U and V filters at several instruments. In the total sample of 27 nights, the U data of 15 nights showe…
Evidence Against Broad Absorption Lines in the X-Ray-bright Quasar PG 1416-129
Green, Paul J.; Mathur, Smita; Schartel, Norbert +1 more
Recent results from the ROSAT All-Sky Survey and from deep ROSAT pointings reveal that broad absorption line quasars (BALQSOs) are weak in the soft X-ray bandpass (αox > 1.8) in comparison to QSOs with normal OUV spectra (αox = 1.4). One glaring exception appeared to be the nearby BALQSO PG 1416-129, which is a bright ROSA…
Coronal and Interplanetary Particle Beams
Aschwanden, Markus J.; Treumann, Rudolf A.
In this report we attempt to synthesize the results of a series of working group discussions focused on the topics of particle beams and particle acceleration in the solar corona and in interplanetary space. We start our discussion of coronal beams with a standard flare scenario, established on recent X-ray (Yohkoh, CGRO) and radio observations, w…
Spatial variations of 0.2 to 5 MeV protons in the 1-5 AU in-ecliptic region from Ulysses, Voyager 1 and 2, and IMP 8 gradient studies
Armstrong, Thomas P.; Boufaida, Moncef
Protons with energies ranging from 0.3 to 2 MeV are nearly always present in the environment of Earth. Solar flare events and interplanetary shock waves can be identified as producing or enhancing these fluxes. However, interplanetary particles are observed even in the absence of solar flares. Explaining the presence of these proton fluxes in the …