Dr. Krawczynski works in the field of High Energy Astrophysics. He studies the astrophysics of supermassive black holes which are found at the centers of galaxies. X-ray and gamma-ray observations make it possible to explore the physical conditions in the surroundings of the black holes, and to study the highly relativistic collimated plasma outflows (jets) which are produced by accretion of interstellar matter onto the black holes. Furthermore, the gamma-ray observations can be used to measure the intensity and the energy spectrum of the intergalactic infrared and optical radiation fields which absorb gamma-rays in pair-production absorption processes. These latter measurements give unique constraints on the early history of structure and star formation in our universe. Another research topic concerns the study of high-energy particle populations which carry a significant fraction of the random energy of galaxies and galaxy clusters and influence important processes like star formation. Krawczynski's research uses the data from the ground based TeV gamma-ray telescope VERITAS and the satellite borne X-ray and gamma-ray telescopes RXTE, INTEGRAL, Suzaku, and Chandra.

As a member of the VERITAS collaboration, Dr. Krawczynski participates in the construction of a system of 4 Cherenkov telescopes which is presently under construction at Mount Hopkins, Az. Each telescope has an optical reflector of 36 feet diameter. The telescope system detects the Cherenkov light of so-called extensive air showers which cosmic GeV/TeV photons initiate in the earth's atmosphere. Dr. Krawczynski works on the astrophysical interpretation of the incoming science data and the development of control software. Furthermore, he is involved in the development of a follow-up experiment.

Dr. Krawczynski works on the development of the space-borne Energetic X-ray Imaging Survey Telescope EXIST. The mission is designed to survey the entire X-ray sky every 95 min. It has the potential to revolutionize our understanding of how supermassive black holes form and grow. Furthermore, it will be an ideal observatory for detecting very distant explosions (gamma-ray bursts). Another activity of Dr. Krawczynski is targeted at the design of the COBRA experiment, which aims at discovering neutrinoless double beta decay events. The experiment has the potential to determine the nature and masses of neutrinos. Neutrinos are a very important constituent of the Universe and their nature and masses are still not well determined.

Both experiments, EXIST and COBRA will make use of thick Cadmium Zinc Telluride (CZT) semiconductor detectors. Dr. Krawczynski's group works on the development of 0.5cm 2cm thick CZT detectors using a class-100 cleanroom and wet-etching, photolithography, and thin film deposition equipment. CZT detectors achieve excellent spatial and energy resolutions without cryogenic cooling. The group specializes on the fabrication of pixelated detectors, and pioneered several novelties such as "electrically isolated" steering grids which steer electrons to the detector pixels while suppressing grid-pixel currents which deteriorate the detectors' energy resolutions. Recently, Krawczynski's group started to develop CZT detectors for the Department of homeland security that can be used to screen ship and truck loads for nuclear contraband.

1994	M.Sc., University of Hamburg, Physics
1997	Ph.D., University of Hamburg, Physics

2002-present	Professor at Washington University
2000-2002	Research Associate and Instructor at Yale University
1997-2000	Research Associate at the Max-Planck-Institute for Nuclear Physics

2007	Outstanding Faculty Mentor Award of the Graduate Student Senate
2004	Department of Energy Outstanding Junior Investigator Award
2001-2002	Gibbs Research/Instructor Fellowship at Yale
1992-1993	German DAAD Fellowship