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Machine learning for effective spacecraft operation: Operating INTEGRAL through dynamic radiation environments
Finn, Timothy; Southworth, Richard; Donati, Alessandro +8 more
INTEGRAL (INTErnational Gamma-Ray Astrophysics Laboratory) is an astronomical observatory of the European Space Agency, responsible for many significant scientific discoveries in the last few decades. It orbits Earth since 2002 in a highly elliptical orbit, passing through the Van Allen belts - areas with high-energy ionized particles that can dam…
Hard X-ray cataclysmic variables
Mukai, K.; de Martino, D.; Masetti, N. +2 more
Among hard X-ray Galactic sources detected with the Swift and INTEGRAL surveys, those discovered as accreting white dwarf binaries have surprisingly boosted in number in the recent years. The majority are identified as magnetic Cataclysmic Variables of the Intermediate Polar type, suggesting this subclass as an important constituent of the Galacti…
Data-driven modelling of the Van Allen Belts: The 5DRBM model for trapped electrons
Kretschmar, Peter; Ness, Jan-Uwe; Kuulkers, Erik +10 more
The magnetosphere sustained by the rotation of the Earth's liquid iron core traps charged particles, mostly electrons and protons, into structures referred to as the Van Allen Belts. These radiation belts, in which the density of charged energetic particles can be very destructive for sensitive instrumentation, have to be crossed on every orbit of…
The X-ray emission of the γ Cassiopeiae stars
Smith, Myron A.; Motch, C.; Lopes de Oliveira, R.
Long considered as the ;odd man out; among X-ray emitting Be stars, γ Cas (B0.5e IV) is now recognized as the prototype of a class of stars that emit hard thermal X-rays. Our classification differs from the historical use of the term ; γ Cas stars; defined from optical properties alone. The luminosity output of this class contributes significantly…
End-of-life disposal of high elliptical orbit missions: The case of INTEGRAL
Armellin, Roberto; San-Juan, Juan F.; Lara, Martin
Nowadays there is international consensus that space activities must be managed to minimize debris generation and risk. The paper presents a method for the end-of-life (EoL) disposal of spacecraft in high elliptical orbits (HEO). The time evolution of HEO is strongly affected by Earth's oblateness and luni-solar perturbation, and this can cause in…
Particle acceleration and gamma rays in solar flares: Recent observations and new modeling
Gan, W. Q.; Miroshnichenko, L. I.
Experiments on SMM, GAMMA, Yohkoh, GRANAT, Compton GRO, INTEGRAL, RHESSI and CORONAS-F satellites over the past three decades have provided copious data for fundamental research relating to particle acceleration, transport and energetics of flares and to the ambient abundance of the solar corona, chromosphere and photosphere. We summarize main res…
Probing the nature of short swift bursts via deep INTEGRAL monitoring of GRB 050925
Sakamoto, T.; Gehrels, N.; Cummings, J. R. +10 more
We present results from Swift, XMM-Newton, and deep INTEGRAL monitoring in the region of GRB 050925. This short Swift burst is a candidate for a newly discovered soft gamma-ray repeater (SGR) with the following observational burst properties: (1) galactic plane (b = -0.1°) localization, (2) 150 ms duration, and (3) a blackbody rather than a simple…
The INTEGRAL view of Gamma-Ray Bursts
McGlynn, S.; Foley, S.; Bazzano, A. +3 more
After more than six and half years in orbit, the ESA space observatory INTEGRAL has provided new, exciting results in the soft gamma-ray energy range (from a few keV to a few MeV). With the discovery of about 700 hard X-Ray sources, it has changed our previous view of a sky composed of peculiar and “monster” sources. The new high energy sky is in …
Soft gamma-ray constraints on a bright flare from the Galactic Center supermassive black hole
Genzel, R.; Pantin, E.; Grosso, N. +11 more
Sagittarius A★(SgrA★) is the supermassive black hole residing at the center of the Milky Way. It has been the main target of an extensive multiwavelength campaign we carried out in April 2007. Herein, we report the detection of a bright flare from the vicinity of the horizon, observed simultaneously in X-rays (XMM-Newton/EPIC…
Study of the 28 October 2003 and 20 January 2005 solar flares by means of 2.223 MeV gamma-emission line
Troitskaia, Evgenia V.; Arkhangelskaja, Irene V.; Miroshnichenko, Leonty I. +1 more
By the data on intensity-time profiles of the neutron capture line of 2.223 MeV we have studied some characteristics of two solar flares, 28 October 2003 and 20 January 2005 (INTEGRAL and CORONAS-F observations, respectively). The SINP code was applied making allowance for the main processes of neutron interactions and deceleration in the solar pl…