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www.aip.de Biennial Report 2004–2005 ASTROPHYSIKALISCHES INSTITUT POTSDAM · Biennial Report 2004 –2005 ASTROPHYSIKALISCHES INSTITUT POTSDAM Optische Aufnahme eines Himmelsauschnitts, in dem der Röntgensatellit XMM-Newton 90 neue Röntgenquellen entdeckt hat. Das optische Bild wurde mit dem "Wide Field Imager" des MPG/ESO 2,2m Teleskops aufgenommen und in mehreren Farbfiltern insgesamt über 7 Stunden belichtet. Imprint Zweijahresbericht des Astrophysikalischen Instituts Potsdam 2004-2005 Herausgeber Astrophysikalisches Institut Potsdam An der Sternwarte 16 · 14482 Potsdam · Germany Telefon +49(0)331 7499 0 · Telefon +49(0)331 7499 209 · www.aip.de Inhaltliche Verantwortung Matthias Steinmetz Redaktion Dierck-Ekkehard Liebscher Design und Layout Dirk Biermann, Stefan Pigur Druck Druckhaus Mitte Berlin Potsdam, Mai 2006 ISBN: XXX 4 Vorwort Preface Astronomie gilt gemeinhin als die Astronomy is usually considered to be the oldest of the sci- älteste Wissenschaft. Astrophysik ist ences. Astrophysics, however, is modern fundamental re- modernste Grundlagenforschung und search that drives many high-tech developments in the areas wesentlicher Treiber für die Entwicklung von Hochtechnologie of optics as well as sensors and information technology. The im Bereich der Optik, der Sensorik und der Informationstech- Astrophysical Institute Potsdam (AIP) is uniquely positioned nologie. An wohl keinem Ort kommen diese beiden Aspekte at this confluence of the history of science on the one hand der Himmelskunde so zusammen wie am Astrophysikalischen side and large international projects on the other hand. In par- Institut Potsdam (AIP), wo die Bewahrung traditionsreicher ticular, the past two years, 2004 and 2005 (the world year of Wissenschaftsgeschichte einhergeht mit der Teilhabe an inter- physics), covered by this biennial report prove the point. nationalen technisch-wissenschaftlichen Großprojekten der Highlights in astrophysical research, in particular the “First Astrophysik. Gerade die beiden Jahre, die dieser Zweijahres- Light“ at the Large Binocular Telescope, as well as cultural bericht abdeckt, das Jahr 2004 und Einsteinjahr 2005, zeugen events like the return of the great refracting telescope to the davon. Astrophysikalische Höhepunkte wie insbesondere das Telegrafenberg deserve special mention. 63 scientific contri- „First Light“ mit dem Large Binocular Telescope stehen kul- butions, 18 project reports and several reports and presen- turellen Höhepunkten, wie der Rückführung des Großen Re- tations covering the situation of the AIP in the years 2004 and fraktors auf den Telegrafenberg gegenüber. Mit 63 wissen- 2005 present current questions and answers of modern schaftlichen Kurzbeiträgen, mit 18 Projektberichten und meh- astrophysical research and everyday life at the AIP and docu- reren Berichten und Darstellungen zur Situation des AIP in den ment the fostering of its scientific and historical legacy. Jahren 2004 und 2005 werden in dem vorliegenden Zwei- We would like to thank our funding agencies and suppor- jahresbericht aktuelle Fragen und Antworten aus der moder- ters, board members and administrative partners for the nen Astrophysik und dem Alltagsleben am AIP präsentiert und good and successful collaboration over the period covered by die Pflege des wissenschaftshistorischen Erbes dokumentiert. this report. An dieser Stelle bedanken wir uns bei den Zuwendungsge- bern, Gremien und unseren wissenschaftlichen und adminis- trativen Kooperationspartnern für die gute und erfolgreiche Zusammenarbeit im Berichtszeitraum. Prof. Matthias Steinmetz Peter A. Stolz Wissenschaftlicher Vorstand Administrativer Vorstand Potsdam, Mai 2006 5 Inhalt Content Vorwort · Preface . 5 Inhalt · Content . 6 Zur Situation des AIP · On the Situation of the AIP . 10 Wissenschaft · Science The MRI gallium experiment PROMISE . 20 Geodynamo alpha-effect and the reversal phenomenon . 22 Stellar dynamos with flip-flop property. 23 Numerical simulation of protostellar core collapse . 24 Numerical simulations of supernova-driven turbulence with NIRVANA3 . 25 Funnel flows from protoplanetary discs . 26 Interstellar turbulence generated by the magnetorotational instablity . 27 The magnetic tachocline of the Sun . 28 GREGOR – a new 1.5 m telescope at Tenerife . 30 Vertical electric current densities in sunspots . 33 Type III radio burst prolific magnetic field configurations . 34 On structure and strength of coronal magnetic fields in postflare loops . 35 Using fiber bursts to measure the coronal magnetic field . 36 First observations of coronal waves with the GOES Solar X-ray Imager . 37 Extrapolation of photospheric magnetic field measurements into the solar corona . 38 Generation of energetic electrons in solar flares . 39 Collisionless heating and acceleration of electrons due to jet propagation in the solar corona . 40 Propagation of energetic electrons in the solar corona and the interplanetary medium . 41 Whistler wave excitation by relativistic electrons during solar flares. 42 Solar prominence eruptions . 43 The diagnostics of unresolved magnetic fields -- a stochastic polarized radiative transfer approach . 44 Stokes profile synthesis of solar-type stars. 46 Spotted stars that get bluer as they get fainter . 47 Magnetic characteristics of sun-like stars . 48 Binarity, activity and metallicity among late-type stars . 49 First accretion-impact maps of a T-Tauri star . 50 Doppler imaging with molecular contribution . 51 The X-ray emission of planetary nebulae . 52 The internal kinematics of planetary nebulae and the problem of their distances. 54 Differential rotation and the meridional flow on giant stars . 56 A Bayesian search for stellar activity cycles . ..
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