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sao-eht / eat

EHT Analysis Toolkit
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check optimal Tdof for adhoc phasing calculation #16

Closed lindyblackburn closed 8 months ago

lindyblackburn commented 8 months ago

The calculation of effective averaging timescale to use for atmospheric phase calibration,

https://github.com/sao-eht/eat/blob/94df36a7b45a6ce6dd2dc005c2b71a81c5d80a00/eat/hops/util.py#L1093

is based on the Eq 21 from https://arxiv.org/abs/1903.08832

The original formula should be double checked.

lindyblackburn commented 8 months ago

Checks out. Note that rho^2 in Eq 18 and Eq 21 has units 1/s.

The prefactor in code is 4pi^2, which is not the same as Eq 21. Unclear now where that is from, but numerically it is very close to the boxcar value in Eq 21 with alpha=5/3, which is reasonable. It's possible that a different window function other than boxcar was used, that resulted in a simpler expression and is more appropriate for the savgol DOF association.