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Incoherent Thomson scattering system for PHAse space MApping (PHASMA) experiment

Shi, Peiyun·Srivastav, Prabhakar·Beatty, Cuyler·Nirwan, Ripudaman Singh·Scime, Earl E.
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Abstract

A new incoherent Thomson scattering system measures the evolution of electron velocity distribution functions perpendicular and parallel to the ambient magnetic field during kinking of a single flux rope and merging of two flux ropes through magnetic reconnection. The Thom-son scattering system provides sub-millimeter spatial resolution, sufficient to diagnose the several millimeters sized magnetic reconnection electron diffusion region in the PHAse Space MAppgin experiment. Due to the relatively modest plasma density ~ 10 19 m -3 and electron tem-perature ~1 eV, stray light suppression is critical for these measurements. Two volume Bragg gratings are used in series as a notch filter with a spectral bandwidth <0.1 nm in the collection branch. A CCD with a Gen III intensifier with peak quantum efficiency >47% is used as the detector in a 1.3 m spectrometer. Preliminary results of gun plasma electron temperature will be reported and compared with measurements obtained from a triple Langmuir probe.

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Shi, Peiyun, Srivastav, Prabhakar, Beatty, Cuyler, Nirwan, Ripudaman Singh, Scime, Earl E.. 2021-03-01. Incoherent Thomson scattering system for PHAse space MApping (PHASMA) experiment. https://doi.org/10.1063/5.0040606

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