1D interferometric Rayleigh scattering velocimetry and thermometry using VIPA.

The work introduces a VIPA-based interferometric Rayleigh scattering instrument for tracer-free, simultaneous temperature and velocity measurements along a 1D volume. A virtually imaged phased array (VIPA) replaces the Fabry-Perot etalon conventionally used in interferometric Rayleigh scattering, allowing the extension of the technique from 0D (point or multi-point) to 1D. The Rayleigh-Brillouin spectrum is a function of pressure and temperature and can be used for temperature diagnostics in isobaric flows.