40 research outputs found
Selective excitation of homogeneous spectral lines
It is possible, for homogeneously broadened lines, to excite selectively the
response signals, which are orders of magnitude narrower than the original
lines. The new type of echo, which allows detecting such signals, and the
formalism, useful for understanding the phenomenon, as well as the experimental
examples from NMR spectroscopy are presented.Comment: 19 pages, 8 figure
Large enhancement of deuteron polarization with frequency modulated microwaves
We report a large enhancement of 1.7 in deuteron polarization up to values of
0.6 due to frequency modulation of the polarizing microwaves in a two liters
polarized target using the method of dynamic nuclear polarization. This target
was used during a deep inelastic polarized muon-deuteron scattering experiment
at CERN. Measurements of the electron paramagnetic resonance absorption spectra
show that frequency modulation gives rise to additional microwave absorption in
the spectral wings. Although these results are not understood theoretically,
they may provide a useful testing ground for the deeper understanding of
dynamic nuclear polarization.Comment: 10 pages, including the figures coming in uuencoded compressed tar
files in poltar.uu, which also brings cernart.sty and crna12.sty files neede