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DOE OSTI · 1540181

DAVIS: A direct algorithm for velocity-map imaging system

Harrison, G. R.·Vaughan, J. C.·Hidle, B.·Laurent, G. M.
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Abstract

Here, we report a direct (non-iterative) algorithm to reconstruct the three-dimensional (3D) momentum-space picture of any charged particles collected with a velocity-map imaging system from the two-dimensional (2D) projected image captured by a position-sensitive detector. The technique consists of fitting the measured image with the 2D projection of a model 3D velocity distribution defined by the physics of the light-matter interaction. The meaningful angle-correlated information is first extracted from the raw data by expanding the image with a complete set of Legendre polynomials. Both the particle’s angular and energy distributions are then directly retrieved from the expansion coefficients. The algorithm is simple, easy to implement, fast, and explicitly takes into account the pixelization effect in the measurement.

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74 ATOMIC AND MOLECULAR PHYSICS

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Harrison, G. R., Vaughan, J. C., Hidle, B., Laurent, G. M.. 2018-05-15. DAVIS: A direct algorithm for velocity-map imaging system. https://doi.org/10.1063/1.5025057

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