Showing papers by "Karsten Danzmann published in 1986"
TL;DR: It is demonstrated that Doppler-free two-photon polarization spectroscopy makes possible Stark profile measurements without Dopplers-broadened background under high-density and high-temperature conditions, e.g., in dense arc plasmas, where other sub-Doppler laser-spectroscopic techniques introduced so far fail.
Abstract: It is demonstrated that Doppler-free two-photon polarization spectroscopy makes possible Stark profile measurements without Doppler-broadened background under high-density and high-temperature conditions, e.g., in dense arc plasmas, where other sub-Doppler laser-spectroscopic techniques introduced so far fail. This method, based on the polarization rotation connected with a two-phonon transition, is not limited by collisions changing the velocity or the excitation of the atoms or by photoionization of the upper level.
35 citations
TL;DR: An upper limit of 3 x 10/sup -10/ decays per projectile is set for the yield integrated over a target thickness of 3.6 mg/cm/sup 2/, which corresponds to a cross section of 3x 10/Sup -29/ cm/Sup 2/ averaged over the target.
Abstract: We have searched for 180/sup 0/ (c.m.) correlated equal-energy two-photon decays produced in 6-MeV/nucleon U+Th collisions. In the summed-energy region between 1.5 and 1.8 MeV, we set an upper limit of 3 x 10/sup -10/ decays per projectile for the yield integrated over a target thickness of 3.6 mg/cm/sup 2/, which corresponds to a cross section of 3 x 10/sup -29/ cm/sup 2/ averaged over the target. This can be compared to a production cross section of (1-2) x 10/sup -28/ cm/sup 2/, averaged over a target thickness of 0.3--0.6 mg/cm/sup 2/ found by others for correlated electron-positron pairs in the same reaction.
8 citations