Quality Control and
Data Processing

HC PLOTS
Spectral Calibration
QC1 database (advanced users): browse | plot

This measures the effective wavelength of each spectral channel by measuring the actual fringes spacing for long scans. This is only possible if the internal piezo scanner is well calibrated/known and linear Data can be taken on sky (used to calibrate sky/interferometric data). or on the internal lamp (to monitor the instrument).
The spectral calibration should be stable (around 2% in the GRISM mode)

The spectral calibration measure the effective weavelength of each spectral channel by measuring the actual fringe spacing during a piezzo scan.

QC1_parameters

FITS key	QC1 database: table, name	definition	class*	HC_plot**	more docu
QC.EFFWAVE	pionier_spectral_calib..spec_cal_effwave	effective wavelength [m],	HC		[docuSys coming]
QC.EFFBAND	pionier_spectral_calib..spec_cal_effband	effective band [m],	HC		[docuSys coming]
QC.EFFWAVE.PTP	pionier_spectral_calib..spec_cal_effwave_ptp	effective wavelength PTP [m],	HC		[docuSys coming]
*Class: KPI - instrument performance; HC - instrument health; CAL - calibration quality; ENG - engineering parameter **There might be more than one.

Trending

The value for the spectral calibration is plotted in the trending plot.
The spectral calibration parameters are plotted for the different set-up

Scoring&thresholds Spectral Calibration

The value of the thresholds have been defined together with the Instrument scientist

History

The evolution of the central wavelength for the different setups is shown here

Algorithm Spectral Calibration

The pipeline computes a Fourier Transform spectrometry on the fringes recorded on long scans and calculates the effective WL and its width for the central Channel. The value of the central wavelength depends of the accuracy of the knowledge of the scan rate of the piezzo .