Eberhard Widmann

Widmann has two main areas of interest:

Priciple of antihydrogen hyperfine experiment

i) Precision experiments with antihydrogen: tests of CPT symmetry and antimatter gravity.
Widmann participates in two collaborations at the Antiproton Decelerator of CERN. ASACUSA aims at a measurement of the hyperfine structure of antihydrogen, the simplest atom consisting purely of antimatter, which is supported by the ERC Advanced Grant Project 291242. This measurement, which is performed in a Rabi-type atomic beam configuration, promises one of the most sensitive tests of CPT symmetry. In parallel, experiments with a cold polarized beam of hydrogen atoms are being performed that are sensitive to coefficients of the Standard Model Extension of Alan Kostelecky that incorporates CPT violation through Lorentz invariance violation. The AEgIS collaboration’s goal is to perform a first precise measurement of the gravitational interaction between matter and antimatter by preparing a horizontal beam of antihydrogen atoms and directly observing its fall in the gravitational field of the earth by means of a classical moiré deflectometer.

Schematic view of the PANDA detector

ii) Study of QCD in the non-perturbative regime at low (exotic kaon-nucleon and kaon-nucleus bound states) and high energies (meson spectroscopy at BELLE and PANDA, studies of the Quark Gluon Plasma with ALICE). In the kaon nucleon interaction bound states of antikaons and nucleons have been predicted, but so far no conclusive experimental evidence has been reported. Widmann participates in several experiments at J-PARC and the AMADEUS experiment at LN Frascati, which will further investigate this question. BELLE data are analysed to perform precision studies of baryon decays in the charmed sector and for the study of resonances in the strangeness sector. In PANDA SMI participates in the development of fast timing detectors and in future in the study of exotic hadrons and in-medium effects of mesons. Within ALICE an analysis group is investigating di-electrons as a tool to both study properties of the Quark Gluon Plasma and the behavior of mesons inside the QGP. Experimentally SMI contributes to the FIT detector through its expertise in fast timing detectors.