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Broadband electrostatic noise and low-frequency waves in the Earth’s magnetosphere
Lakhina, G. S.; Singh, S. V.; Reddy, R. V.
Broadband electrostatic noise (BEN) is commonly observed in different regions of the Earth's magnetosphere, eg., auroral region, plasma sheet boundary layer, etc. The frequency of these BENs lies in the range from lower hybrid to the local electron plasma frequency and sometimes even higher. Spacecraft observations suggest that the high and low-fr…
The White Dwarf in EM Cygni: Beyond the Veil
Sion, Edward M.; Godon, Patrick; Barrett, Paul E. +1 more
We present a spectral analysis of the Far Ultraviolet Spectroscopic Explorer (FUSE) spectra of the eclipsing double-line spectroscopic binary EM Cygni (EM Cyg), a Z Cam DN system. The FUSE spectrum, obtained in quiescence, consists of four individual exposures (orbits): two exposures, at orbital phases phi ~ 0.65 and phi ~ 0.90, have a lower flux;…
Quasiperiodic ULF-pulsations in Saturn's magnetosphere
Krupp, N.; Dougherty, M. K.; Glassmeier, K. -H. +2 more
Recent magnetic field investigations made onboard the Cassini spacecraft in the magnetosphere of Saturn show the existence of a variety of ultra low frequency plasma waves. Their frequencies suggest that they are presumably not eigenoscillations of the entire magnetospheric system, but excitations confined to selected regions of the magnetosphere.…
Relative Velocities and Linewidths in a Coronal Hole and Outside
Raju, K. P.
Relative Doppler velocities and spectral linewidths in a coronal hole and in the quiet Sun region outside have been obtained from Solar and Heliospheric Observatory (SOHO)/Coronal Diagnostic Spectrometer (CDS) observations. Five strong emission lines in the CDS wavelength range (namely, O III 599 Å, O V 630 Å, Ne VI 562.8 Å, He II 304 Å, and Mg IX…
Far-Ultraviolet Dust Albedo Measurements in the Upper Scorpius Cloud Using the Spinr Sounding Rocket Experiment
France, K.; Gordon, K. D.; Chakrabarti, S. +3 more
The Spectrograph for Photometric Imaging with Numeric Reconstruction sounding rocket experiment was launched on 2000 August 4 to record far-ultraviolet (912-1450 Å) spectral and spatial information for the giant reflection nebula in the Upper Scorpius region. The data were divided into three arbitrary bandpasses (912-1029 Å, 1030-1200 Å, and 1235-…
Analysis of Breit-Pauli Transition Probabilities for Lines in O III
Rubin, R. H.; Froese Fischer, C.; Tachiev, G. +1 more
Accurate atomic data are essential for understanding the properties of both O III lines produced by the Bowen fluorescence mechanism and [O III] forbidden lines observed in numerous gaseous nebulae. Improved Breit-Pauli transition probabilities have been published for the carbon sequence. Included were revised data for O III. The present paper ana…
Near-infrared observations of the HE0450-2958 system: discovery of a second active galactic nucleus?
Magain, P.; Chantry, V.; Letawe, G. +1 more
The quasi-stellar object (QSO) HE0450-2958 was brought to the front scene by the non-detection of its host galaxy and strong upper limits on the latter's luminosity. The QSO is also a powerful infrared emitter, in gravitational interaction with a strongly distorted ultraluminous infrared companion galaxy. We investigate the properties of the compa…
Scales in a thinning plasma sheet
Petrukovich, A. A.; Balogh, A.; Nakamura, R. +3 more
With Cluster observations in the magnetotail, we study the dynamics of plasma sheet thinning and stretching in a typical growth phase event of September 12, 2001. The thinning and stretching proceed in parallel, with transient variations. The pre-onset value is Bz∼1.5 nT, J∼8 nA/m2. The current density increase is not accompa…
Soft gamma-ray sources detected by INTEGRAL
Strong, A.; Beckmann, V.; Halloin, H. +1 more
Aims: We aim to exploit the available INTEGRAL/SPI data to provide time-averaged spectra of the brightest soft gamma-ray sources.
Methods: Employing a maximum-likelihood fit technique for our SPI data analysis, we take as input to our source model the source catalog derived by Bouchet et al. (2008) from a SPI all-sky study. We use the first fo…
Solar wind periodicity in energetic electrons at Saturn
Krupp, N.; Krimigis, S. M.; Mitchell, D. G. +2 more
Fluxes of energetic electrons (110-365 keV) have been subjected to a long-term Lomb periodogram analysis from the middle of 2004 to the middle of 2009. Fluxes within 20 RS and outside the magnetopause were excluded, so only fluxes within the magnetosphere were included in the analysis. The periodicity “box” was expanded from 5 hours to …