18 research outputs found
Polarized nuclear target based on parahydrogen induced polarization
We discuss a novel concept of a polarized nuclear target for accelerator
fixed-target scattering experiments, which is based on parahydrogen induced
polarization (PHIP). One may be able to reach a 33% free-proton polarization in
the ethane molecule. The potential advantages of such a target include
operation at zero magnetic field, fast (100 Hz) polarization reversal,
and operation with large intensity of an electron beam.Comment: 16 pages, 2 figure
Optical detection of NMR J-spectra at zero magnetic field
Scalar couplings of the form J I_1 \cdot I_2 between nuclei impart valuable
information about molecular structure to nuclear magnetic-resonance spectra.
Here we demonstrate direct detection of J-spectra due to both heteronuclear and
homonuclear J-coupling in a zero-field environment where the Zeeman interaction
is completely absent. We show that characteristic functional groups exhibit
distinct spectra with straightforward interpretation for chemical
identification. Detection is performed with a microfabricated optical atomic
magnetometer, providing high sensitivity to samples of microliter volumes. We
obtain 0.1 Hz linewidths and measure scalar-coupling parameters with 4-mHz
statistical uncertainty. We anticipate that the technique described here will
provide a new modality for high-precision "J spectroscopy" using small samples
on microchip devices for multiplexed screening, assaying, and sample
identification in chemistry and biomedicine.Comment: 15 pages, 4 Figure
