Calibration Access and Data Handbook

Generation from Ground Calibration Data

A spatial and spectral information of the zodiacal light emission is taken from literature:

• Levasseur-Regourd & Dumont (A&A, 1980, 84, 277)
• Leinert et al. (A&AS, 1998, 127, 1)

The spatial distribution of the zodiacal light is contained in the ZODIACAL_MAP extension. Helioecliptic coordinates are used.
The zodiacal light spectrum (essentially solar) is compiled from literature and written into the extension ZODIACAL_SPEC. The intensity of the spectrum is scaled to the reference intensity. The photon rates are estimated by folding the zodiacal light spectrum with the OM response. The binary table ZODIACAL_CTS lists the expected photon rates for the different filters at the reference intensity.

Image extension: ZODICAL_MAP

keyword	keyword	keyword	comment
name	type	value
BITPIX	integer	-32	number of bits per data pixel
NAXIS	integer	2	number of data axes
NAXIS1	integer	may vary	length of data axis 1
NAXIS2	integer	may vary	length of data axis 2
BUNIT	string	S10(V)	Units of the image
CTYPE1	string	'ecliptic longitude / [deg]'	name of x-axis
CTYPE2	string	'ecliptic latitude / [deg]'	name of y-axis
CRVAL1	real	may vary	[degree] x-coordinate of reference bin
CRVAL2	real	may vary	[degree] y-coordinate of reference bin
CRPIX1	integer	1	[bin] address of reference bin x-direction
CRPIX2	integer	1	[bin] address of reference bin y-direction
CDELT1	real	may vary	[degree] increment in x-direction
CDELT2	real	may vary	[degree] increment in y-direction

Binary table: ZODICAL_SPEC

keyword	keyword	keyword	comment
name	type	value
REFINTEN	real	may vary	reference intensity of spectrum [S10(V)]
column name	column type	column unit	comment
LAMBDA	E	nm	wavelength of bin
FLUX	E	$W/m^2/nm/deg^2$	zodiacal light flux at reference intensity

Binary table: ZODICAL_COUNTS

keyword	keyword	keyword	comment
name	type	value
REFINTEN	real	may vary	reference intensity of count rates [S10(V)]
column name	column type	column unit	comment
FILTER_ID	9A	-	filter identifier
COUNTS	E	photons/sec/subpixel	photon rate at reference intensity