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GRI: focusing on the evolving violent universe
Knödlseder, Jürgen; Christensen, Finn; Bazzano, Angela +4 more
The gamma-ray imager (GRI) is a novel mission concept that will provide an unprecedented sensitivity leap in the soft gamma-ray domain by using for the first time a focusing lens built of Laue diffracting crystals. The lens will cover an energy band from 200-1,300 keV with an effective area reaching 600 cm2. It will be complemented by a…
LAPLACE: A mission to Europa and the Jupiter System for ESA's Cosmic Vision Programme
Drossart, Pierre; Hartogh, Paul; Sotin, Christophe +40 more
The exploration of the Jovian System and its fascinating satellite Europa is one of the priorities presented in ESA’s “Cosmic Vision” strategic document. The Jovian System indeed displays many facets. It is a small planetary system in its own right, built-up out of the mixture of gas and icy material that was present in the external region of the …
Cross-scale: multi-scale coupling in space plasmas
Sahraoui, Fouad; Horbury, Timothy; Sauvaud, Jean-André +17 more
Most of the visible universe is in the highly ionised plasma state, and most of that plasma is collision-free. Three physical phenomena are responsible for nearly all of the processes that accelerate particles, transport material and energy, and mediate flows in systems as diverse as radio galaxy jets and supernovae explosions through to solar fla…
Realization of X-ray telescopes-from design to performance
Aschenbach, Bernd
For more than 45 years the building of X-ray telescopes for solar and astronomical observations has been practised with significant performance improvement. The various techniques applied are reviewed emphazising the impact of proper mirror material choice, grinding and polishing improvements and the role of metrology.
Interstellar heliospheric probe/heliospheric boundary explorer mission—a mission to the outermost boundaries of the solar system
Wimmer-Schweingruber, Robert F.; Valtonen, Eino; Wurz, Peter +4 more
The Sun, driving a supersonic solar wind, cuts out of the local interstellar medium a giant plasma bubble, the heliosphere. ESA, jointly with NASA, has had an important role in the development of our current understanding of the Suns immediate neighborhood. Ulysses is the only spacecraft exploring the third, out-of-ecliptic dimension, while SOHO h…
History of gamma-ray telescopes and astronomy
Pinkau, Klaus
Gamma-ray astronomy is devoted to study nuclear and elementary particle astrophysics and astronomical objects under extreme conditions of gravitational and electromagnetic forces, and temperature. Because signals from gamma rays below 1 TeV cannot be recorded on ground, observations from space are required. The photoelectric effect is dominant <…
AKARI: space infrared cooled telescope
Onaka, Takashi; Salama, Alberto
AKARI, formerly known as ASTRO-F, is the second Japanese space mission to perform infrared astronomical observations. AKARI was launched on 21 February 2006 (UT) and brought into a sun-synchronous polar orbit at an altitude of 700 km by a JAXA M-V rocket. AKARI has a telescope with a primary-mirror aperture size of 685 mm together with two focal-p…
Gamma-ray telescopes. 400 Years of astronomical telescopes
Gehrels, Neil; Cannizzo, John K.
The last half-century has seen dramatic developments in γ-ray telescopes, from their initial conception and development through to their blossoming into full maturity as a potent research tool in astronomy. Gamma-ray telescopes are leading research in diverse areas such as γ-ray bursts, blazars, Galactic transients, and the Galactic distribution o…
Fresnel zone plate telescopes for X-ray imaging II: numerical simulations with parallel and diverging beams
Rao, A. R.; Girish, V.; Nandi, Anuj +4 more
We present the results of simulations of shadows cast by a zone plate telescope which may have one to four pairs of zone plates. From the shadows we reconstruct the images under various circumstances. We discuss physical basis of the resolution of the telescope and demonstrate this by our simulations. We allow the source to be at a finite distance…