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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…
Structures induced by small moonlets in Saturn's rings: Implications for the Cassini Mission
Seiß, M.; Spahn, F.; Sremčević, M. +1 more
Particle simulations are carried out to study density features caused by small moonlets embedded in a dense planetary ring. The creation of a ``propeller'' like structure is found together with adjacent density wakes. Both features are clear indications for the existence of moonlets in the rings. We confirmed that the propeller scales with the Hil…
The connection between ultraviolet and X-ray outflows in active galactic nuclei: the case of PDS 456
Simpson, Chris; O'Brien, Paul T.; Reeves, James N. +1 more
High-velocity outflows from active galactic nuclei are a well-known phenomenon in terms of the broad absorption lines seen in the ultraviolet/optical. More recently, similar, possibly related, outflows have been reported in the X-ray. The most extreme example is seen in the nearby, luminous QSO PDS 456, which displays a massive, high-velocity (500…
XMM-Newton View of the Ultraluminous X-Ray Sources in M51
Dewangan, Gulab C.; Griffiths, Richard E.; Miyaji, Takamitsu +2 more
We present results based on XMM-Newton observations of the nearby spiral galaxy M51 (NGC 5194 and NGC 5195). We confirm the presence of the seven known ultraluminous X-ray sources (ULXs) with luminosities exceeding the Eddington luminosity for a 10 Msolar black hole, a low-luminosity active galactic nucleus (LLAGN) with 2-10 keV luminos…
Spatially resolved spectroscopy of the E+A galaxies in the z= 0.32 cluster AC 114
Kuntschner, Harald; Bekki, Kenji; Colless, Matthew +5 more
We present spatially resolved intermediate-resolution spectroscopy of a sample of 12 E+A galaxies in the z= 0.32 rich galaxy cluster AC 114, obtained with the FLAMES multi-integral field unit system on the Very Large Telescope (VLT) of the European Southern Observatory. Previous integrated spectroscopy of all these galaxies by Couch & Sharples…