# Momentum measurement ## Measurement with Multiple Coulomb Scattering There are many algorithms in FEDRA for momentum measurement through MCS. The code is written in src/libEdr/EdbMomentumEstimator.h. The function PMS() launch the algorithm according to parameter eAlg: * **eAlg 0: PMSang** (eTrack): default version, modified by Magali at the end of 2008 * **eAlg 1: PMSang\_base (**eTrack): original version (Momentum estimation by multiple scattering (Annecy algorithm Oct-2007)) * **eAlg 2: PMSang\_base\_A** (eTrack): include asymmetrical errors in scattering VS ncell graphs, based on ChiSquare distribution * **eAlg 3: PMScoordinate** (eTrack): momentum estimation by coordinate method * **eAlg 4: PSMang\_corr** (eTrack): with corrections by Ash Momentum measurement with PMSang was used also in SHiP-charm by Valerio --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://antonio-iuliano1993.gitbook.io/software-notes/fedra/momentum-measurement.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.