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A solar spectrum for PFS data analysis
Formisano, Vittorio; Fiorenza, Carlo
A measured calibrated solar radiance in the range 1.2- 5µm, with the spectral sampling of 1cm-1 does not exist. When studying the measured Planetary Fourier Spectrometer (PFS) spectra of the Earth's or Mars's atmosphere we discover that the most used solar spectrum contains several important errors. Here we present a "calibrated" …
Theoretical Interpretation of the Luminosity and Spectral Properties of GRB 031203
Ruffini, Remo; Bernardini, Maria Grazia; Fraschetti, Federico +3 more
The X-ray and gamma-ray observations of the source GRB 031203 by INTEGRAL are interpreted within our theoretical model. In addition to a complete spacetime parameterization of the GRB, we specifically assume that the afterglow emission originates from a thermal spectrum in the comoving frame of the expanding baryonic matter shell. By determining t…
X-Ray Timing, Spectroscopy, and Photometry of the Anomalous X-Ray Pulsar Candidate CXOU J010043.1-721134
Ransom, S. M.; Gaensler, B. M.; Kaspi, V. M. +2 more
We present new X-ray timing and spectral results on the 8.0 s X-ray pulsar CXOU J010043.1-721134 from a series of observations using the Chandra X-Ray Observatory. We found a spin period in 2004 January of 8.020392+/-0.000009 s. A comparison of this to the 2001 Chandra observations implies a period derivative P˙=(1.88+/-0.08)×10-11 s s<…
On the Combination of Differential Emission Measure Analysis and Rotational Tomography for Three-dimensional Solar EUV Imaging
Frazin, R. A.; Weber, M. A.; Kamalabadi, F.
Conventional differential emission measure (DEM) analysis allows one to determine the amount of plasma as a function of temperature along a given line of sight. A completely different technique called solar rotational tomography (SRT) exploits the view angles provided by solar rotation to determine the spatial distribution of emissivity in three d…
X-ray observations of the edge-on star-forming galaxy NGC 891 and its supernova SN1986J
Stevens, Ian R.; Raychaudhury, Somak; Temple, Rowan F.
We present XMM-Newton observations of NGC 891, a nearby edge-on spiral galaxy. We analyse the extent of the diffuse emission emitted from the disc of the galaxy, and find that it has a single-temperature profile with best-fitting temperature of 0.26 keV, though the fit of a dual-temperature plasma with temperatures of 0.08 and 0.30 keV is also acc…
Solar energetic electrons related to the 28 October 2003 flare
Krucker, S.; Mann, G.; Kunow, H. +4 more
We investigate the solar origin of near-relativistic electrons and protons during the X17.2/4B flare as observed by the Comprehensive Suprathermal and Energetic Particle Analyser (COSTEP) and Three-Dimensional Plasma (3DP) analyzer experiments on board the SOHO and Wind spacecraft. These observations are combined with ground- and space-based spect…
The First Precise Determination of an Optical-Far-Ultraviolet Extinction Curve Beyond the Local Group (z=0.83)
Kochanek, C. S.; Arribas, S.; Muñoz, J. A. +3 more
We present the optical-far-ultraviolet extinction curve of the dust in the lens galaxy of the gravitational lens system SBS 0909+532 (z=0.83). Extending our previous optical-UV estimate (from λ-10~2 to 5 µm-1) into the far ultraviolet (from λ-10~5 to 8 µm-1) is crucial f…
A Multi-Instrument Study of the Helix Nebula Knots with the Hubble Space Telescope
O'Dell, C. R.; Henney, W. J.; Ferland, G. J.
We have conducted a combined observational and theoretical investigation of the ubiquitous knots in the Helix Nebula (NGC 7293). We have constructed a combined hydrodynamic + radiation model for the ionized portion of these knots and have accurately calculated a static model for their molecular regions. Imaging observations in optical emission lin…
Independent Global Modes of Solar Magnetic Field Fluctuations
Lawrence, J. K.; Cadavid, A. C.; Ruzmaikin, A. +1 more
Observed solar, interplanetary and geomagnetic time series contain quasi periodicities on scales of 1-2.5 years. The further discovery of 1.3 year fluctuations in helioseismic observations suggests that a variety of signals may be related to the underlying dynamo in the Sun. We use independent component analysis to study the temporal and spatial v…
Ion sound wave packets at the quasiperpendicular shock front
Krasnoselskikh, V.; Dunlop, M.; Fazakerley, A. +6 more
Electric field measurements from a single spacecraft have been used to study ion-sound turbulence observed within the Earth's bow shock. The observed frequency of the ion-sound waves can be both lower and higher than the local electron cyclotron frequency depending upon the direction of wave propagation in the plasma rest frame. The ion-sound wave…