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sammy_to_nereids_resolution

Function sammy_to_nereids_resolution 

Source
pub fn sammy_to_nereids_resolution(
    inp: &SammyInpConfig,
) -> Option<(f64, f64, f64, f64)>
Expand description

Convert SAMMY resolution parameters to NEREIDS-convention values.

SAMMY stores resolution parameters in a different convention from NEREIDS:

SAMMY coefficientFormulaNEREIDS equivalent
Ao2 = (1.20112·Deltag / (Sm2·Dist))²timingdelta_t = Deltag / (2·√ln2)
Bo2 = (0.81650·Deltal / Dist)²pathdelta_l = Deltal / √6

where 1.20112 = 1/√ln2, 0.81650 = √(2/3), Sm2 = TOF_FACTOR = 72.298.

SAMMY Ref: RslResolutionFunction_M.f90 (getAo2 lines 143-161, getBo2 lines 165-179)

Returns None if all effective Deltal, Deltag, and Deltae are zero (no resolution broadening). Otherwise returns Some((flight_path_m, delta_t_us, delta_l_m, delta_e)).

The fourth element delta_e is the exponential tail parameter (raw SAMMY Deltae units, passed through without conversion). When non-zero, the resolution kernel is the convolution of a Gaussian with an exponential tail (SAMMY Iesopr=3).