Spectrally Narrowed 1.5 KW Optical Pumping Laser for Large-Scale SEOP Production of Hyperpolarized Gases

F. W. Hersman^1,2, Jan H. Distelbrink², Jeff Ketel², David Watt², Stephen Ketel², Walter Porter², Steve Bryn², Aaron Hope², Iulian Constantin Ruset²

Hyperpolarized gases xenon-129 and helium-3 are novel imaging agents for pulmonary functional MRI that are in investigational use in clinical research. Producing these gases with spin-exchange optical pumping (SEOP) requires high power laser sources spectrally narrowed at 795nm. We present a new implementation of optical elements incorporated in an external cavity spectrally-locked diode laser system and report measurements confirming production of 1.5 kilowatt laser power with spectral width of less than 0.2nm at 795nm central wavelength and angular divergence less than 0.1mr (fast axis) X 5mr (slow axis).