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Updated: Aug 15, 2026

Hyperpolarized Xenon for NMR and MRI Applications
Published on: September 6, 2012
Accelerating the spontaneous emission of x rays from atoms in a cavity
R Röhlsberger1, K Schlage, T Klein
1Deutsches Elektronen Synchrotron (DESY), Notkestrasse 85, 22607 Hamburg, Germany.
Abstract:
We have investigated the spontaneous radiative decay of resonant nuclei in a planar x-ray waveguide after excitation by synchrotron radiation pulses. The waveguide acts as a cavity and modifies the mode structure of the electromagnetic field. As a result, the rate of spontaneous emission is enhanced by a factor proportional to the density of photon states in the cavity. In this experiment, we have observed a sixfold acceleration of the coherent radiative decay of 57Fe nuclei located in the center of the first-order guided mode. This is in very good agreement with theoretical predictions.
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