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INTEGRAL discovery of a bright highly obscured galactic X-ray binary source IGR J16318-4848
de Plaa, J.; Parmar, A. N.; Tomsick, J. A. +8 more
INTEGRAL regularly scans the Galactic plane to search for new objects and in particular for absorbed sources with the bulk of their emission above 10-20 keV. The first new INTEGRAL source was discovered on 2003 January 29, 0.5degr from the Galactic plane and was further observed in the X-rays with XMM-Newton. This source, IGR J16318-4848, is intri…
Transverse dimensions of chorus in the source region
Gurnett, D. A.; Santolík, O.
We report measurement of whistler-mode chorus by the four Cluster spacecraft at close separations. We focus our analysis on the generation region close to the magnetic equatorial plane at a radial distance of 4.4 Earth's radii. We use both linear and rank correlation analysis to define perpendicular dimensions of the sources of chorus elements bel…
Modelling the rotational modulation of the Sun as a star
Barge, P.; Llebaria, A.; Pagano, I. +2 more
We analyse the time variability of the total solar irradiance (TSI) as measured by VIRGO/SoHO in order to model the variability of the Sun as a star. Apart from the phases near the minimum at the beginning of activity cycle 23, the period of the rotational modulation is significantly different from the solar synodic period as a consequence of the …
The Formation of Nuclear Rings in Barred Spiral Galaxies
Teuben, Peter; Regan, Michael W.
Although nuclear rings of gas and star formation are common in barred spiral galaxies, current theories of why and how they form do not provide the level of detail needed to quantify the effect that these rings can have on the fueling of active galactic nuclei and on the evolution of their host galaxy. In this paper we use detailed modeling to sho…
Far-Ultraviolet Spectra of Fast Coronal Mass Ejections Associated with X-Class Flares
Raymond, J. C.; Dobrzycka, D.; Ciaravella, A. +4 more
The Ultraviolet Coronagraph Spectrometer (UVCS) on board the Solar and Heliospheric Observatory satellite has observed very fast coronal mass ejections (CMEs) associated with X-class flares. These events show spectral signatures different from those seen in most other CMEs in terms of very rapid disruption of the pre-CME streamer, very high Dopple…
Barred Galaxies at z > 0.7: NICMOS Hubble Deep Field-North Observations
Scoville, Nicholas Z.; Sheth, Kartik; Regan, Michael W. +1 more
Previous optical studies found an unexpected deficit of bars at z>0.7. To investigate the effects of band shifting, we have studied the fraction of barred spiral galaxies in the Near-Infrared Camera and Multi-Object Spectrometer (NICMOS) Hubble Deep Field-North. At z>0.7, we find at least four barred spiral galaxies, doubling the number prev…
Analyses on the geometrical structure of magnetic field in the current sheet based on cluster measurements
Balogh, A.; Baker, D. N.; Wang, X. +5 more
The geometrical structure of the magnetic field is a critical character in the magnetospheric dynamics. Using the magnetic field data measured by the Cluster constellation satellites, the geometrical structure including the curvature radius, directions of curvature, and normal of the osculating planes of the magnetic field lines within the current…
A star-forming galaxy at z= 5.78 in the Chandra Deep Field South
Bunker, Andrew J.; McMahon, Richard G.; McCarthy, Patrick J. +2 more
We report the discovery of a luminous z= 5.78 star-forming galaxy in the Chandra Deep Field South. This galaxy was selected as an `i-drop' from the GOODS public survey imaging with the Hubble Space Telescope/Advanced Camera for Surveys (object 3 in the work of Stanway, Bunker & McMahon 2003). The large colour of (i'-z')AB= 1.6 indic…
GRB 021004: A Possible Shell Nebula around a Wolf-Rayet Star Gamma-Ray Burst Progenitor
Mirabal, N.; Filippenko, Alexei V.; Halpern, J. P. +7 more
The rapid localization of GRB 021004 by the HETE-2 satellite allowed nearly continuous monitoring of its early optical afterglow decay, as well as high-quality optical spectra that determined a redshift of z3=2.328 for its host galaxy, an active starburst galaxy with strong Lyα emission and several absorption lines. Spectral observation…
Numerical modelling of gamma radiation from galaxy clusters
Miniati, Francesco
We investigate the spatial and spectral properties of non-thermal emission from clusters of galaxies at γ-ray energies. We estimate the radiation flux between 10 keV and 10 TeV due to inverse-Compton (IC) emission, π0-decay and non-thermal bremsstrahlung (NTB) from cosmic ray (CR) ions and electrons accelerated at cosmic shocks as well …