Quality Control and
Data Processing

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

QC1_parameters

FITS key	QC1 database: table, name	definition	class*	HC_plot**	more docu
QC.SPEC.EFFICIENCY1	fors2_response..efficiency_1	efficiency at 9300 A	HC		[docuSys coming]
QC.SPEC.EFFICIENCY2	fors2_response..efficiency_2	efficiency at 4100 A	HC		[docuSys coming]
QC.SPEC.EFFICIENCY3	fors2_response..efficiency_3	efficiency at 4500 A	HC		[docuSys coming]
QC.SPEC.EFFICIENCY4	fors2_response..efficiency_4	efficiency at 4900 A	HC		[docuSys coming]
QC.SPEC.EFFICIENCY5	fors2_response..efficiency_5	efficiency at 5300 A	HC		[docuSys coming]
QC.SPEC.EFFICIENCY6	fors2_response..efficiency_6	efficiency at 5700 A	HC		[docuSys coming]
QC.SPEC.EFFICIENCY7	fors2_response..efficiency_6	efficiency at 5700 A	HC		[docuSys coming]
QC.SPEC.EFFICIENCY8	fors2_response..efficiency_8	efficiency at 6500 A	HC		[docuSys coming]
QC.SPEC.EFFICIENCY9	fors2_response..efficiency_9	efficiency at 6900 A	HC		[docuSys coming]
QC.SPEC.EFFICIENCY10	fors2_response..efficiency_10	efficiency at 7300 A	HC		[docuSys coming]
QC.SPEC.EFFICIENCY11	fors2_response..efficiency_11	efficiency at 7700 A	HC		[docuSys coming]
QC.SPEC.EFFICIENCY12	fors2_response..efficiency_12	efficiency at 8100 A	HC		[docuSys coming]
QC.SPEC.EFFICIENCY13	fors2_response..efficiency_13	efficiency at 8500 A	HC		[docuSys coming]
QC.SPEC.EFFICIENCY14	fors2_response..efficiency_14	efficiency at 8900 A	HC		[docuSys coming]
QC.SPEC.EFFICIENCY15	fors2_response..efficiency_15	efficiency at 9300 A	HC		[docuSys coming]
*Class: KPI - instrument performance; HC - instrument health; CAL - calibration quality; ENG - engineering parameter **There might be more than one.

Trending

Efficiency in different grisms is trended. Only data obtained during photometric nights with binning 2x2 and standard resolution collimator are used. Only data points for the upper CCD are plotted. The lower CCD usually has no standard stars and no response curve.

Scoring&thresholds Efficiency

No threshold nor scoring applied.

History

Since 2011-01-17 we use the new Paranal extinction curve.

Algorithm Efficiency

The efficiency parameters are derived from MOS observations of spectrophotometric standard stars. These spectrophotometric standard stars are acquired with the MOS #10 slit with the slit width of 5 arcsec. MOS slit #10 is projected on the upper CCD of the FORS2 mosaic detector. The position of the MOS #10 slit is either in the center to calibrate MXU and MOS science observations or it is shifted to one of the seven positions of the LSS slits to calibrate LSS science spectra. (see Appendix E.2 of the FORS2 User Manual for the long slit positions).

The efficiency is taken from the efficiency curve at the given wavelength (starting at 3700Å and ending at 9300Å). The efficiency curve is derived by comparing observed flux values to tabulated ones and is then strongly smoothed. For more details see the FORS2 pipeline manual.

The spectrophotometric standard star observations are taken within three days of the corresponding science observations and are meant to provide a response curve for data reduction. They can also be used to determine the efficiency of the spectroscopic modes of FORS2, provided they have been taken under photometric conditions which however is not guaranteed.