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Module calibration

Module calibration 

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SDK-free Bruker timsTOF axis calibration.

Pure-Rust ports of the calibration formulas Bruker publishes for the TDF format, so that TOF-index -> m/z and scan -> 1/K0 can be computed without loading the proprietary libtimsdata SDK. The algorithms mirror the implementation in PAPPSO’s GPL library libpappsomspp (mzcalibrationmodel1.cpp, timsframebase.cpp); the coefficient meanings are cross-checked against Bruker’s own tims_calibration.py reference.

Two independent models are involved, each carrying its own ModelType:

  • m/z : MzCalibration table (this data set: ModelType 2)
  • 1/K0 : TimsCalibration table (this data set: ModelType 2)

IMPORTANT (m/z): PAPPSO only implements m/z ModelType 1. Modern instruments write ModelType 2, whose first coefficients (C0,C1) still describe the same t = C0 + sqrt(1e12/C1)*sqrt(m) base curve, but which adds a degree-6 correction polynomial (C8..C14) that neither PAPPSO nor this module models. We therefore reproduce the base curve exactly (few-ppm agreement with the SDK) and, for genuine ModelType-1 data, the full cubic-in-sqrt(m) curve.

Structs§

MobilityCalibrator
Ion-mobility axis calibration (Bruker “model type 2”, the only TIMS model).
MzCalibrator
m/z axis calibration (Bruker “model type 1” base curve + optional cubic).