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Abstract A two order of magnitude spectral acquisition improvement in velocity distribution function measurement is demonstrated with a novel single-shot, dual-color coherent Rayleigh–Brillouin scattering (CRBS) scheme. By performing this non-resonant and seedless spectral diagnostic technique, capable of obtaining a spectrum in $\sim 300$ ns, we demonstrate accurate temperature (ranging from 300 K to 500 K) and pressure (ranging from 760 Torr down to 1 Torr) measurement capabilities, for a variety of atomic, molecular and multispecies gases. This demonstrated gas thermodynamic characterization capability of the dual-color CRBS scheme over broad ranges of pressure and temperature for a variety of gases is anticipated to be of great interest to a plethora of fields, ranging from aerospace applications to low-temperature plasmas, providing with an accurate measurement of physical properties of neutral particles, for a range of gases. 

A dual color, frequency and pulse duration agile laser system, capable of delivering laser pulses in arbitrary temporal profiles with ∼1 ns to ∼1 µs pulse duration, chirping rates of ∼27 MHz/ns with an achievable chirping range of several GHz across the pulse duration, and with energies ranging from a few nJ to hundreds of mJ per pulse has been developed. The flexibility and capability of this laser system provide a wide range of laser parameters that can be exploited to optimize operational conditions in various experiments ranging from laser diagnostics to spectroscopy and optical manipulation of matter. The developed system is successfully demonstrated to obtain coherent Rayleigh-Brillouin scattering (CRBS) in both single and dual color configuration, in an effort to expand the non-intrusive accessibility towards lower pressure regime for neutral gas and plasma diagnostics.