F E T 3 2 1 Given a FIGS data cube as produced by the FIGS data acquisition system running in one of the etalon modes, processes it to produce a single spectrum, for one of the detectors only. Command parameters - 'CUBE' The name of the cube from which the planes are to be taken. This should be a raw FIGS data cube. 'DETECTOR' The number of the detector to be used. 'SPECTRUM' The name of the resulting spectrum. 'CUTOFF' The level (in sigma) at which a point will be ignored (FIGS321 only) Command keywords - 'ADD' Add the data together rather than subtracting the beamswitch and chop backgrounds 'BACK' Return the background spectrum only 'NORM' Normalize data to mean level of each cycle. Input data - CUBE is assumed to have a structure with the actual cube data in CUBE.Z.DATA This routine assumes that the first axis of the cube data represents wavelength, that the second represents spectral scans in the order A1a,A1b,B1a,B1b,B2a,B2b,A2a,A2b, where A1,A2,B1,B2 represent the parts of the beamswitch ABBA cycle and a and b represent the signal and background chop positions respectively. In etalon mode 2, there are no chop positions, and the second axis is just A1,B1,A2,B2. This means that the second dimension of the cube has to be either 4 or 8. The cube third axis represents beamswitch cycle number. The data is normalized to give a figure in detected photons per second. Along the wavelength axis, the data is assumed to be in order of etalon position, each etalon position having n values where n is the number of detectors used. Output data - IMAGE is created with the same structure as CUBE except that .Z.DATA will only have 1 dimension, and any .Y or .T sub-structures that CUBE has will be deleted. If a spectrum is produced the errors (derived from the cycle to cycle statistics) are placed in the .Z.ERRORS component 5th May 1988 KS / AAO. Original version, based on FIGS321.
FIGARO A general data reduction system