transform from center-of-mass frame to lab frame

[yuqizhuyqz]

Hi Dr. Issac Lenton,

I'm trying to do some scattering calculations with OTT in MATLAB. I'm able to follow the beam_visualization.m example and calculate the scattered fields when the trap beam (a gaussian beam) is offset from the particle. As I understand it, everything is in the particle's center-of-mass frame. I want to transform the far-field solutions back into the lab frame after the scattering calculation. Could you advise how I should proceed? Currently, translation in Y (using .translateXyz) seems to also cause some tilt in the far-field solutions without applying any scattering matrix. I attached a plot to show how the beam profile in blue in the translated Y dimension looks skewed in the particle's COM frame in the far field regime. I want to be in a rest frame of this incoming trap beam, where I think the beam profiles in any XY planes would look translated and not skewed. Any suggestions are appreciated.

Thanks, Yuqi