TY - BOOK A1 - Karg, Detlef A1 - Schopper, Franz A1 - Paschke, Ralph A1 - Meyer, Michael A1 - Ackermann, Irmgard A1 - Baxmann, Matthias A1 - Buchinger, Marie-Luise A1 - Cante, Marcus A1 - Dreger, Hans-Joachim A1 - Gramlich, Sybille A1 - Schwarz, Ulrike A1 - Hübener, Dieter A1 - Metzler, Matthias A1 - Niemann, Alexander A1 - Rohowski, Ilona A1 - Senst, Ingetraud A1 - Groß, Wera ED - Brandenburgisches Landesamt für Denkmalpflege und Archäologisches Landesmuseum, T1 - Denkmalentdeckungen BT - Bilder aus dem Land Brandenburg N2 - »Wenn du reisen willst, mußt du die Geschichte dieses Landes kennen und lieben. Das ist ganz unerläßlich. [...] Wag’ es getrost und du wirst es nicht bereuen. Eigentümliche Freuden und Genüsse werden dich begleiten. Du wirst Entdeckungen machen, denn überall wohin du kommst, wirst du, vom Touristenstandpunkt aus, eintreten wie in ›jungfräuliches Land‹. Du wirst Klosterruinen begegnen, von deren Existenz höchstens die nächste Stadt eine leise Kenntnis hatte; du wirst inmitten alter Dorfkirchen, deren zerbröckelter Schindelturm nur auf Elend deutete, große Wandbilder oder in den treppenlosen Grüften reiche Kupfersärge mit Kruzifix und vergoldeten Wappenschildern finden; du wirst Schlachtfelder überschreiten, Wendenkirchhöfe, Heidengräber, von denen die Menschen nichts mehr wissen.« Die in diesem Bildband gesammelten »Denkmalentdeckungen« verstehen sich als Einladung zu einer Reise durch das Land Brandenburg. Theodor Fontane hatte für ein solches Unternehmen genau den richtigen Blick, als er in seinen »Wanderungen durch die Mark Brandenburg« 1864 diese Sätze schrieb. Auch heute noch sollten wir seiner Anregung zu Begegnungen mit der Geschichte und der Kunstgeschichte des Landes folgen, die uns im Dialog der Kulturen und der Zeiten eine Standortbestimmung in der Gegenwart und eine Orientierung für die Zukunft zugleich bietet. KW - Brandenburg KW - Denkmal KW - Denkmalpflege KW - Bildband KW - Tourismus Y1 - 2007 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-72290 SN - 978-3-88462-244-5 PB - Wernersche Verlagsgesellschaft CY - Worms ET - 1200 ER - TY - JOUR A1 - Jao, Chun-Sung A1 - Vafin, Sergei A1 - Chen, Ye A1 - Gross, Matthias A1 - Krasilnikov, Mikhail A1 - Loisch, Gregor A1 - Mehrling, Timon A1 - Niemiec, Jacek A1 - Oppelt, Anne A1 - de la Ossa, Alberto Martinez A1 - Osterhoff, Jens A1 - Pohl, Martin A1 - Stephan, Frank T1 - Preliminary study for the laboratory experiment of cosmic-rays driven magnetic field amplification JF - High Energy Density Physics N2 - To understand astrophysical magnetic-field amplification, we conducted a feasibility study for a laboratory experiment of a non-resonant streaming instability at the Photo Injector Test Facility at DESY, Zeuthen site (PITZ). This non-resonant streaming instability, also known as Bell’s instability, is generally regarded as a candidate for the amplification of interstellar magnetic field in the upstream region of supernova-remnant shocks, which is crucial for the efficiency of diffusive shock acceleration. In the beam-plasma system composed of a radio-frequency electron gun and a gas-discharge plasma cell, the goal of our experiment is to demonstrate the development of the non-resonant streaming instability and to find its saturation level in the laboratory environment. Since we find that the electron beam will be significantly decelerated on account of an electrostatic streaming instability, which will decrease the growth rate of desired non-resonant streaming instability, we discuss possible ways to suppress the electrostatic streaming instability by considering the characteristics of a field-emission-based quasi continuous-wave electron beam. KW - Laboratory astrophysics KW - Beam-plasma instability KW - Magnetic field amplification KW - Radio-frequency electron gun KW - Field-emission-based quasi continuous-wave electron beam Y1 - 2019 U6 - https://doi.org/10.1016/j.hedp.2019.04.001 SN - 1574-1818 SN - 1878-0563 VL - 32 SP - 31 EP - 43 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Chen, Ye A1 - Loisch, Gregor A1 - Gross, Matthias A1 - Jao, Chun-Sung A1 - Krasilnikov, Mikhail A1 - Oppelt, Anne A1 - Osterhoff, Jens A1 - Pohl, Martin A1 - Qian, Houjun A1 - Stephan, Frank A1 - Vafin, Sergei T1 - Generation of quasi continuous-wave electron beams in an L-band normal conducting pulsed RF injector for laboratory astrophysics experiments JF - Nuclear instruments & methods in physics research : a journal on accelerators, instrumentation and techniques applied to research in nuclear and atomic physics, materials science and related fields in physics ; A, Accelerators, spectrometers, detectors and associated equipment N2 - We report on an approach to produce quasi continuous-wave (cw) electron beams with an average beam current of milliamperes and a mean beam energy of a few MeV in a pulsed RF injector. Potential applications are in the planned laboratory astrophysics programs at DESY. The beam generation is based on field emission from a specially designed metallic field emitter. A quasi cw beam profile is formed over subsequent RF cycles at the resonance frequency of the gun cavity. This is realized by debunching in a cut disk structure accelerating cavity (booster) downstream of the gun. The peak and average beam currents can be tuned in beam dynamics simulations by adjusting operation conditions of the booster cavity. Optimization of the transverse beam size at specific positions (e.g., entrance of the plasma experiment) is performed by applying magnetic focusing fields provided by solenoids along the beam line. In this paper, the design of a microtip field emitter is introduced and characterized in electromagnetic field simulations in the gun cavity. A series of particle tracking simulations are conducted for multi-parametric optimization of the parameters of the produced quasi cw electron beams. The obtained results will be presented and discussed. In addition, measurements of the parasitic field emission (PFE) current (dark current) in the PITZ gun will be exemplarily shown to distinguish its order of magnitude from the produced beam current by the designed field emitter. KW - Cw electron beam KW - RF gun KW - Booster cavity KW - Laboratory astrophysics KW - Field emission KW - Beam dynamics Y1 - 2018 U6 - https://doi.org/10.1016/j.nima.2018.06.063 SN - 0168-9002 SN - 1872-9576 VL - 903 SP - 119 EP - 125 PB - Elsevier CY - Amsterdam ER -