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The Max Planck Institute for Extraterrestrial Physics is a Max Planck Institute, located in Garching, near Munich, Germany.In 1991 the Max Planck Institute for Physics and Astrophysics split up into the Max Planck Institute for Extraterrestrial Physics, the Max Planck Institute for Physics and the Max Planck Institute for Astrophysics. The Max Planck Institute for Extraterrestrial Physics was founded as sub-institute in 1963. Thescientific activities of the institute are mostly devoted to astrophysics with telescopes orbiting in space. A large amount of the resourcesare spent for studying black holes in the galaxy and in the remote universe. Wikipedia.

van Eerten H.,Max Planck Institute for Extraterrestrial Physics
Monthly Notices of the Royal Astronomical Society | Year: 2014

A sufficiently powerful astrophysical source with power-law luminosity in time will give rise to a self-similar relativistic blast wave with a reverse shock travelling into the ejecta and a forward shock moving into the surrounding medium. Once energy injection ceases and the last energy is delivered to the shock front, the blast wave will transit into another self-similar stage depending only on the total amount of energy injected. I describe the effect of limited duration energy injection into environments with density depending on radius as a power law, emphasizing optical/X-ray Gamma-ray Burst afterglows as applications. The blast wave during injection is treated analytically, the transition following last energy injection with one-dimensional simulations. Flux equations for synchrotron emission from the forward and reverse shock regions are provided. The reverse shock emission can easily dominate, especially with different magnetizations for both regions. Reverse shock emission is shown to support both the reported X-ray and optical correlations between afterglow plateau duration and end time flux, independently of the luminosity power-law slope. The model is demonstrated by application to bursts 120521A and 090515, and can accommodate their steep post-plateau light-curve slopes. © 2014 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society. Source

Diehl R.,Max Planck Institute for Extraterrestrial Physics
Reports on Progress in Physics | Year: 2013

Measurements of high-energy photons from cosmic sources of nuclear radiation through ESA's INTEGRAL mission have advanced our knowledge: new data with high spectral resolution showed that characteristic gamma-ray lines from radioactive decays occur throughout the Galaxy in its interstellar medium. Although the number of detected sources and often the significance of the astrophysical results remain modest, conclusions derived from this unique astronomical window of radiation originating from nuclear processes are important, complementing the widely-employed atomic-line based spectroscopy. We review the results and insights obtained in the past decade from gamma-ray line measurements of cosmic sources in the context of their astrophysical questions. © 2013 IOP Publishing Ltd. Source

Lutz D.,Max Planck Institute for Extraterrestrial Physics
Annual Review of Astronomy and Astrophysics | Year: 2014

Roughly half of the radiation from evolving galaxies in the early Universe reaches us in the far-infrared and submillimeter wavelength ranges. Recent major advances in observing capabilities, in particular the launch of the Herschel Space Observatory in 2009, have dramatically enhanced our ability to use this information in the context of multiwavelength studies of galaxy evolution. Near its peak, three-quarters of the cosmic infrared background is now resolved into individually detected sources. The use of far-infrared diagnostics of dust-obscured star formation and of interstellar medium conditions has expanded from extreme and rare extreme high-redshift galaxies to more typical main-sequence galaxies and hosts of active galactic nuclei out to z≳2. These studies shed light on the evolving role of steady equilibrium processes and of brief starbursts at and since the peak of cosmic star formation and black hole accretion. This review presents a selection of recent far-infrared studies of galaxy evolution with an emphasis on Herschel results. Copyright © 2014 by Annual Reviews. Source

Tanaka Y.,Max Planck Institute for Extraterrestrial Physics
Annual Review of Astronomy and Astrophysics | Year: 2013

My research career began with cosmic-ray physics. Invited to the Netherlands, I was engaged in the measurement of cosmic-ray electrons. In parallel, we began balloon observations of the cosmic X-ray background. Coming back to Nagoya, we carried out rocket observations of soft X-rays with a thin polypropylene window. Since moving to the Institute of Space and Aeronautical Science (ISAS: later reorganized to the Institute of Space and Astronautical Science), I have been involved in several astronomical satellite programs, in particular X-ray astronomy missions. The main features and major results of those programs are mentioned. Features characteristic of the Japanese space program and the specific roles of ISAS are explained. Copyright ©2013 by Annual Reviews. All rights reserved. Source

Haerendel G.,Max Planck Institute for Extraterrestrial Physics
Astrophysical Journal | Year: 2012

This paper deals with the acceleration of high-energy flare electrons by field-parallel electric fields in an approach tailored after the auroral acceleration process. Electromagnetic energy, derived from the release of magnetic shear stresses, is converted into kinetic energy of particles. The stress release is enabled by field-aligned potential drops generated by anomalous resistivity of highly filamentary currents. The high-energy flare electrons are identified with runaway particles of this process. The magnetic shear stresses originate from Alfvén waves emitted from high-beta loop-top plasma which is produced by braking of the outflow from a reconnection site higher up in the corona. Partial reflection of the waves at the interface to the chromosphere leads to evaporation of chromospheric plasma and creation of a strongly filamentary structure in the sheared coronal field. The energy conversion process propagates spontaneously, like an erosion process in three dimensions. The overall stress release site forms a thin triangular sheet growing along and perpendicular to the field. After about one second, its cross-section perpendicular to B has grown to tens of square kilometers. This spontaneous growth strongly alleviates the demands on the primary filamentary structure posed by the condition of current criticality. Energy flux and mean energy are of the magnitude typical for hard X-rays producing electrons. Their strong dependence on the ambient magnetic field in combination with the fast propagation of the energy conversion sites could lead to energy-dependent time delays of a few 100ms, much longer than the time-of-flight effects of the electrons. © 2012 The American Astronomical Society. All rights reserved. Source

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