Vis Calibrated Quad Frame Product

Metadata

Data product name

DpdVisCalibratedQuadFrame

Data product custodian

VIS

Name of the Schema file

euc-vis-CalibratedQuadFrame.xsd

Processing Element(s) creating/using the data product

VIS_science_xml_out

Processing function using the data product

SHE and MER processing functions.

Proposed for inclusion in EAS/SAS

Yes

Data product elements

Header

object of type sys:genericHeader

Data

object of type vis:visCalibratedQuadFrame

QualityFlags

object of type dqc:sqfDpdCalibratedFrame

Parameters

object of type ppr:genericKeyValueParameters

Detailed description of the data product

The VIS processing function provides a CalibratedQuadFrame product consisting of 3 FITS files per exposure: a calibrated VIS individual exposure, and the corresponding Background map and Weight map.

A PSF file is also provided. This corresponds to the PSF part of the Vis PSF Model Product.

In all products, pixels are delivered at the native pixel scale and all extensions have the same pixel scale and size. Pixel data is in 32-bit floating point format.

The unit of the pixel is ADU for all products. To convert the image to electrons you need to multiply it by the GAIN, which is expressed in e-/ADU.

To convert the image into mJy, you need to use

\begin{aligned} m_{AB} &= -2.5 \log_{10}(ADU) + Z_p + 2.5 \log_{10}(t_{\text{exp}}) \\ S_{mJy} &= 10^{\frac{23.9 - m_{AB}}{2.5}} \end{aligned}

Some exposures cannot be used for scientific purposes, or can only be used with certain precautions. These include exposures affected by stray light, X-rays, or guidance errors. For selected useful data, some metrics are included in the .xml file that follows each FITS file. See the Vis Analysis Results Product for how to interpret these metrics.

Changes introduced by the PF version

PF 14.0

  • This data product is added in replacement of DpdVisCalibratedFrame.

  • Flags definition changes.

  • Contents of VIS Noise map updated.

  • Invalidate quadrants which contain too many cosmic rays.

  • Add PSF statistics and quality plots.

PF 15.0

  • Flags definition changes.

  • Quadrants containing too many cosmic rays are not invalidated.

  • New FITS keyword COSMICPC containing the percentage of COSMIC flagged pixels in extension.

  • Astrometry: if pointing reconstruction fails, use commanded pointing instead of crashing, set PTG_RECD to false and DpdVisCalibratedQuadFrame.Header.AutomatedValidationStatus set to INVALID.

PF 17.0

  • No major change in this product.

PF 18.0

  • New CR detection with the stack based methode. Only the flag map and weight map is updated after this detection, not the catalogue.

  • Adjust parameter in NoiseChisel

PF 18.1

  • Improved version of StackCRFlagging

  • Correct blooming threshold

Calibrated VIS individual exposure

The calibrated VIS individual exposure is a multi-extension FITS file containing 3 extensions per quadrant, one for pixel data, one for the associated RMS map and one for the associated Flagmap, making 432 extensions for the full 144 quadrants which constitutes an exposure.

Each extension contains the keyword EXTNAME, which is <detector id>.SCI, <detector id>.RMS or <detector id>.FLG for Science, RMS map and Flagmap respectively. The “detector id” describes the extension following the scheme given in the VIS FPA ICD (EUCL-SAP-ICD-6-001).

Name of file:

EUC_VIS_SWL_DET-[ObsId]-[Dither]-[exposure]-0000000__[YYYYMMDDThhmmss.s]Z.fits.gz

where the date is the production date.

SCI extension

The SCI extension contains calibrated pixel data for each of the VIS instrument quadrants. The individual images contain both an astrometric and photometric solution written in the FITS header.

No flux scaling is applied, but the results of the photometric solution computed by VIS are written in the FITS header keywords.

The images are not background subtracted, but a background map is provided as a FITS file with the same pixel size as the individual images.

The astrometric solution is described as a PV projection. Images are not resampled and are delivered at the native VIS pixel scale (which of course means that the optical distortion of the instrument is still present). WCSFITS is used to compute the astrometric solution. It uses a Vis Distortion Model Product of the FPA to compute the astrometric solution (pointing and position angle). The pointing position is the centre of rotation of the FOV and is defined as the centre of the VIS FPA.

../../_images/CCD_numbering1.png

Fig. 12 : CCD numbering and location at detector plane level (Front view) from VIS FPA ICD (EUCL-SAP-ICD-6-001) issue 2.5 2014/20/10

RMS extension

The RMS map contains the noise at each pixel in the corresponding Science image, expressed as the absolute standard deviation and is the one to use for photometry. It is calculated from the quadratic sum of the signal (background+objects in the science image) plus the readout noise.

Please note that the RMS map is not flagged/masked; it contains the invalid pixel values.

Note

In the first PF version (before PF 14.0), RMS map was the BACKGROUND_RMS SExtractor checkimage. These maps are generated by calculating the standard deviation of pixels in a sliding window on the input images, after object removal.

FLG extension

Flagmap define if a pixel is usable for science or not.

The Flagmap definition is presented in Vis Flag Map Product in a human readable format.

Unusable pixel are affected by the flag INVALID (flag value 1). Therefore, all odd pixels must not be used.

Important

If more than 5% of pixels in a quadrant are identified as cosmic ray, the entire quadrant is flag with CR_REGION (flag value 512). However CR_REGION is not part of INVALID flag.

For scientific analysis, it is recommended to manually exclude quadrants marked with this flag.

Data Header

Key

Primary Header

SIMPLE

file does conform to FITS standard

BITPIX

number of bits per data pixel

NAXIS

number of data axes

EXTEND

FITS dataset may contain extensions

FITS_DEF

FITS definition name

FITS_VER

FITS definition version

TIMESYS

Time scale of the time-related keywords

PLAN_ID

32-bit SOC Operation ID

BUNIT

Pixel data unit, e.g. ‘electrons’ or ‘adu’

OBASW

On board application software version: version.

DATE

UT date when this file was created

SOFTVERS

version of the simulator or version of the LE1

EXPTIME

Commanded integration time in seconds, e.g. 565

IMG_CAT

Data product category: SCIENCE, CALIB, TECHNICA

IMG_T1

values in {BIAS, DARK, FLAT, LINEARITY, CHARGE_INJ

IMG_T2

values in {LAMP, SKY, DOME, OTHER…} from SEQU

OBSMODE

Observation Mode (WIDE, DEEP, CALIBRATION)

OBSTYPE

DP technique (IMAGE, SPECTROIMAGE)

INSTRUME

VIS, or VISsim for simulations

TELESCOP

Telescope name: EUCLID

OBT_STA1

Integer, number of seconds of OBT (START_TIME)

OBT_STA2

Integer, number of milliseconds of OBT (START_TIME)

DATE-OBS

Inst. seq. start time in UTC

MJD-OBS

Inst. seq. start time in MJD

FIELDID

Field Id

OBS_ID

Observation Id

DITHOBS

Dither number

PTGID

Pointing Id

EXPNUM

Exposure Id in dither

TOTEXP

Total number of Exposures in the specific Point

INSTRMOD

VIS intrument mode: Science or Manual

COMPALGO

Science TM compression mode: NoCompression, Co

COMPPARA

Science TM compression parameters: pixels/block

RA

reconstructed pointing RA

DEC

reconstructed pointing DEC

PA

reconstructed position angle

SEQID

VIS sequences as defined in EUCL-IFS-ICD-6-002

DATE-END

Inst. seq. end time in UTC

OBT_END1

Integer, number of seconds of OBT (VIS sequence

OBT_END2

Integer, number of milliseconds of OBT (VIS seq

NOMCHAIN

Nominal or redundant electronic chain

VSTART

Index of first readout line (starting at 0)

VEND

Index of last readout line + 1

ROECFGID

ROE configuration table ID

RSUSINID

Table version of RSU SINE table used in the RSU

RSUFRID

Table version of RSU FREQ table used in the RSU

RSUSFRID

Table version of RSU short FREQ table used in t

RSUCFSTA

Shutter unit configuration status: CLOSED_LOOP,

TP_STAT

Trap pumping status: off, parallel, serial, mul

CUSTATUS

Calibration unit status: On or Off

CI_STAT

Charge injection status: On or Off

IDLTIME

Time (s) between end of shutter opening or end

OBT_STA

OBT at start time

DATE-ENH

UTC of LE1 Enhancement

AUX_VERS

LE1 Enh. (AUX) Processor name & version

ELAT

Ecliptic latitude of the commanded attitude

ELONG

Ecliptic longitude of the commanded attitude

POS

Position Angle of the commanded attitude

ALPHA

Solar Alpha angle, in degrees, at the start of the exposure (commanded)

BETA

Solar Beta angle, in degrees, at the start of the exposure (commanded)

SAA

Solar Aspect Angle of the commanded attitude

PATCH_ID

Patch Id

FOV_LAT1

RA of the common Field of View Corner 1

FOV_LAT2

RA of the common Field of View Corner 2

FOV_LAT3

RA of the common Field of View Corner 3

FOV_LAT4

RA of the common Field of View Corner 4

FOV_LON1

Dec of the common Field of View Corner 1

FOV_LON2

Dec of the common Field of View Corner 2

FOV_LON3

Dec of the common Field of View Corner 3

FOV_LON4

Dec of the common Field of View Corner 4

VS1T2043

Quad E/F of CCD6-1, 6-2, 6-3 ROE temperature

VS1T2050

Quad G/H of CCD6-1, 6-2, 6-3 ROE temperature

VS1T2020

CCD1-1 Quad E/F temperature

VS1T2021

CCD1-1 Quad G/H temperature

VS1T2028

CCD1-2 Quad E/F temperature

VS1T2029

CCD1-2 Quad G/H temperature

VS1T2036

CCD1-3 Quad E/F temperature

VS1T2037

CCD1-3 Quad G/H temperature

VS2T2043

Quad E/F of CCD2-1, 2-2, 2-3 ROE temperature

VS2T2050

Quad G/H of CCD2-1, 2-2, 2-3 ROE temperature

VS2T2020

CCD2-1 Quad E/F temperature

VS2T2021

CCD2-1 Quad G/H temperature

VS2T2028

CCD2-2 Quad E/F temperature

VS2T2029

CCD2-2 Quad G/H temperature

VS2T2036

CCD2-3 Quad E/F temperature

VS2T2037

CCD2-3 Quad G/H temperature

VS3T2043

Quad E/F of CCD3-1, 3-2, 3-3 ROE temperature

VS3T2050

Quad G/H of CCD3-1, 3-2, 3-3 ROE temperature

VS3T2020

CCD3-1 Quad E/F temperature

VS3T2021

CCD3-1 Quad G/H temperature

VS3T2028

CCD3-2 Quad E/F temperature

VS3T2029

CCD3-2 Quad G/H temperature

VS3T2036

CCD3-3 Quad E/F temperature

VS3T2037

CCD3-3 Quad G/H temperature

VS4T2043

Quad E/F of CCD4-1, 4-2, 4-3 ROE temperature

VS4T2050

Quad G/H of CCD4-1, 4-2, 4-3 ROE temperature

VS4T2020

CCD4-1 Quad E/F temperature

VS4T2021

CCD4-1 Quad G/H temperature

VS4T2028

CCD4-2 Quad E/F temperature

VS4T2029

CCD4-2 Quad G/H temperature

VS4T2036

CCD4-3 Quad E/F temperature

VS4T2037

CCD4-3 Quad G/H temperature

VS5T2043

Quad E/F of CCD5-1, 5-2, 5-3 ROE temperature

VS5T2050

Quad G/H of CCD5-1, 5-2, 5-3 ROE temperature

VS5T2020

CCD5-1 Quad E/F temperature

VS5T2021

CCD5-1 Quad G/H temperature

VS5T2028

CCD5-2 Quad E/F temperature

VS5T2029

CCD5-2 Quad G/H temperature

VS5T2036

CCD5-3 Quad E/F temperature

VS5T2037

CCD5-3 Quad G/H temperature

VS6T2043

Quad E/F of CCD6-1, 6-2, 6-3 ROE temperature

VS6T2050

Quad G/H of CCD6-1, 6-2, 6-3 ROE temperature

VS6T2020

CCD6-1 Quad E/F temperature

VS6T2021

CCD6-1 Quad G/H temperature

VS6T2028

CCD6-2 Quad E/F temperature

VS6T2029

CCD6-2 Quad G/H temperature

VS6T2036

CCD6-3 Quad E/F temperature

VS6T2037

CCD6-3 Quad G/H temperature

VS7T2043

Quad E/F of CCD1-4, 1-5, 1-6 ROE temperature

VS7T2050

Quad G/H of CCD1-4, 1-5, 1-6 ROE temperature

VS7T2020

CCD1-6 Quad E/F temperature

VS7T2021

CCD1-6 Quad G/H temperature

VS7T2028

CCD1-5 Quad E/F temperature

VS7T2029

CCD1-5 Quad G/H temperature

VS7T2036

CCD1-4 Quad E/F temperature

VS7T2037

CCD1-4 Quad G/H temperature

VS8T2043

Quad E/F of CCD2-4, 2-5, 2-6 ROE temperature

VS8T2050

Quad G/H of CCD2-4, 2-5, 2-6 ROE temperature

VS8T2020

CCD2-6 Quad E/F temperature

VS8T2021

CCD2-6 Quad G/H temperature

VS8T2028

CCD2-5 Quad E/F temperature

VS8T2029

CCD2-5 Quad G/H temperature

VS8T2036

CCD2-4 Quad E/F temperature

VS8T2037

CCD2-4 Quad G/H temperature

VS9T2043

Quad E/F of CCD3-4, 3-5, 3-6 ROE temperature

VS9T2050

Quad G/H of CCD3-4, 3-5, 3-6 ROE temperature

VS9T2020

CCD3-6 Quad E/F temperature

VS9T2021

CCD3-6 Quad G/H temperature

VS9T2028

CCD3-5 Quad E/F temperature

VS9T2029

CCD3-5 Quad G/H temperature

VS9T2036

CCD3-4 Quad E/F temperature

VS9T2037

CCD3-4 Quad G/H temperature

VSAT2043

Quad E/F of CCD4-4, 4-5, 4-6 ROE temperature

VSAT2050

Quad G/H of CCD4-4, 4-5, 4-6 ROE temperature

VSAT2020

CCD4-6 Quad E/F temperature

VSAT2021

CCD4-6 Quad G/H temperature

VSAT2028

CCD4-5 Quad E/F temperature

VSAT2029

CCD4-5 Quad G/H temperature

VSAT2036

CCD4-4 Quad E/F temperature

VSAT2037

CCD4-4 Quad G/H temperature

VSBT2043

Quad E/F of CCD5-4, 5-5, 5-6 ROE temperature

VSBT2050

Quad G/H of CCD5-4, 5-5, 5-6 ROE temperature

VSBT2020

CCD5-6 Quad E/F temperature

VSBT2021

CCD5-6 Quad G/H temperature

VSBT2028

CCD5-5 Quad E/F temperature

VSBT2029

CCD5-5 Quad G/H temperature

VSBT2036

CCD5-4 Quad E/F temperature

VSBT2037

CCD5-4 Quad G/H temperature

VSCT2043

Quad E/F of CCD6-4, 6-5, 6-6 ROE temperature

VSCT2050

Quad G/H of CCD6-4, 6-5, 6-6 ROE temperature

VSCT2020

CCD6-6 Quad E/F temperature

VSCT2021

CCD6-6 Quad G/H temperature

VSCT2028

CCD6-5 Quad E/F temperature

VSCT2029

CCD6-5 Quad G/H temperature

VSCT2036

CCD6-4 Quad E/F temperature

VSCT2037

CCD6-4 Quad G/H temperature

POS_X

Spescraft position x

POS_Y

Spescraft position y

POS_Z

Spescraft position z

VEL_X

Spescraft velocity x

VEL_Y

Spescraft velocity y

VEL_Z

Spescraft velocity z

CALBLKID

Calblock id

CALBLKVR

Calblock variant

DATASETR

PPO DataSetRelease

N_CCD

BIASSEC

Offset area relative to readout, 1-based

REFCAT

reference star catalogue fi

FPAMODEL

MAGZEROP

zero-point

PHOT_ERR

self calibration photometric error

PHOTIRMS

self calibration mag dispersion RMS

APERCORR

self calibration aperture correction MAG_50pix - MAG_13pix

APCORRMS

self calibration aperture correction RMS

FLXSCALE

Flux scaling for stacked exposure

Key

Extension Header For CalibratedFrame

XTENSION

IMAGE extension

BITPIX

number of bits per data pixel

NAXIS

number of data axes

NAXIS1

length of data axis 1

NAXIS2

length of data axis 2

PCOUNT

required keyword; must = 0

GCOUNT

required keyword; must = 1

EXTNAME

DETID

CCD-ID field from science TM (0-35)

CCDID

e.g. Detector ID, e.g. ‘0-0’, ‘1-1’ … ‘6-6’

QUADID

e.g. Quadrant ID, e.g. ‘E’, ‘F’, ‘G’ or ‘H’

ROEID

ROE ID: 1-12

ROECTV

ROE configuration table version

BUNIT

Pixel data unit, e.g. ‘electrons’ or ‘adu’

PRESCANX

number of serial prescan pixels, e.g 51

OVRSCANX

number of serial overscan pixels, e.g 29

OVRSCANY

number of parallel overscan pixels, e.g 20

EXPDUR1

Nominal/Short, nominal with CI, Flat: duration

EXPDUR2

Nominal/Short, nominal with CI, Flat: duration

CRVAL1

CRVAL2

CRPIX1

CRPIX2

CD1_1

CD1_2

CD2_1

CD2_2

CTYPE1

CTYPE2

CUNIT1

CUNIT2

WCSAXES

CMPRTSCI

Quadrant image compression ratio obtained on-bo

GAIN

/mnt/gfs2/work_dir/CACHE/01/7f/EUC_VIS_MDL-GAIN

RDNOISE

/mnt/gfs2/work_dir/CACHE/ae/77/EUC_VIS_MDL-RON_

RA

DEC

PA

EXPTIME

SATLEVEL

pixel saturation level in e-

SATURATE

pixel saturation level in ADU

BIAS_LVL

BIAS_RON

BIAS_TOP

BIAS_BTM

BIAS_LFT

BIAS_RGT

GAINCORR

ref_gain/cal_gain (3.480/3.432)

LSFCORR

large-scale flat corrected

COSMICPC

percent of COSMIC flagged pixels in extension

STDCRMS

NUMBRMS

AVGRESID

PV1_0

PV1_1

PV1_2

PV1_3

PV1_4

PV1_5

PV1_6

PV1_7

PV1_8

PV1_9

PV1_10

PV2_0

PV2_1

PV2_2

PV2_3

PV2_4

PV2_5

PV2_6

PV2_7

PV2_8

PV2_9

PV2_10

PTG_RECD

pointing refitted, true or false

RA_COMM

commanding pointing RA

DEC_COMM

commanding pointing DEC

PA_COMM

commanding position angle

RADESYS

coordinate reference frame

DATE-OBS

TIMESYS

MJD-OBS

MAGZEROP

zero-point

PHOT_ERR

self calibration photometric error

PHOTIRMS

self calibration mag dispersion RMS

APERCORR

self calibration aperture correction MAG_50pix

APCORRMS

self calibration aperture correction RMS

FLXSCALE

Flux scaling for stacked exposure

Weight Map

When combining multiple dithered exposures from separate detectors with gaps it becomes important to assign a “confidence” to each detector pixel so that overlapping exposures can be combined and the noise level at each pixel can be correctly estimated. It is used in input of SWarp for produce Vis Stacked Frame Product.

It corresponds to the small scale flat —reflecting the Pixel Response Non-Uniformity (PRNU)— where all invalid pixels are flagged with a weight of 0.

Name of file:

EUC_VIS_SWL_WGT-[ObsId]-[Dither]-[exposure]-0000000__[YYYYMMDDThhmmss.s]Z.fits.gz

where the date is the production date.

Data Header

Primary Header for Weight Map

SIMPLE

conforms to FITS standard

BITPIX

array data type

NAXIS

number of array dimensions

EXTEND

Extension Header for Weight Map

XTENSION

Image extension

BITPIX

array data type

NAXIS

number of array dimensions

NAXIS1

NAXIS2

PCOUNT

Number of parameters

GCOUNT

Number of groups

EXTNAME

CCDID

WCSAXES

CTYPE1

Coordinamte 1 type

CTYPE2

Coordinamte 2 type

CUNIT1

Physical units of CRVAL1

CUNIT2

Physical units of CRVAL2

CRPIX1

CRPIX2

CD1_1

CD1_2

CD2_1

CD2_2

CRVAL1

CRVAL2

STDCRMS

NUMBRMS

AVGRESID

PV1_1

PV2_1

PV1_2

PV2_2

PV1_4

PV2_4

PV1_5

PV2_5

PV1_6

PV2_6

PV1_7

PV2_7

PV1_8

PV2_8

PV1_9

PV2_9

PV1_10

PV2_10

RA_COMM

commanding pointing RA

DEC_COMM

commanding pointing DEC

PA_COMM

commanding position angle

RA

reconstructed pointing RA

DEC

reconstructed pointing DEC

PA

reconstructed position angle

REFCAT

reference star catalogue file

FPAMODEL

fpa model file

Background Map

The background map delivered is calculated using NoiseChisel.

It seems that NoiseChisel is able to capture the straylight and lot of feature. However for large object the background calculation can be not optimal.

As NoiseChisel is more sensitive to cosmic we have implemented some fall-back in case of crash. The type of background calculation can be found in the Vis Analysis Results Product associated with these different values:

  • NC1 : NoiseChisel methode 1

  • NC2 : NoiseChisel methode 2

  • HISTMODE : Mod of the image

Name of file:

EUC_VIS_SWL_BKG-[ObsId]-[Dither]-[exposure]-0000000__[YYYYMMDDThhmmss.s]Z.fits.gz

where the date is the production date.

Note

At the beginning VIS used the SExtractor background. But we found it was not optimal. In VIS-PF 15.0.4 we switched to use NoiseChisel, which shows improvement in background calculation.

Data Header

Primary Header for Background Map

SIMPLE

This is a FITS file

BITPIX

NAXIS

EXTEND

This file may contain FITS extensions

NEXTEND

Number of extensions

MAGZEROP

zero-point

PHOT_ERR

self calibration photometric error

PHOTIRMS

self calibration mag dispersion RMS

APERCORR

self calibration aperture correction MAG_50pix - MAG_13pix

APCORRMS

self calibration aperture correction rms error

EXPTIME

Commanded integration time in seconds, e.g. 565.0

Extension Header for Background Map

XTENSION

Image extension

BITPIX

array data type

NAXIS

number of array dimensions

NAXIS1

NAXIS2

PCOUNT

Number of parameters

GCOUNT

Number of groups

EXTNAME

DETID

CCD-ID field from science TM (0-35)

CCDID

Detector ID, e.g. ‘0-0’, ‘1-1’ … ‘6-6’

ROEID

ROE ID: 1-12

ROECTV

ROE configuration table version

BUNIT

Pixel data unit, e.g. ‘electrons’ or ‘adu’

PRESCANX

Number of serial prescan pixels, e.g 51

OVRSCANX

Number of serial overscan pixels, e.g 29

OVRSCANY

Number of parallel overscan pixels, e.g 20

EXPDUR1

Nominal/Short, nominal with CI, Flat: duration

EXPDUR2

Nominal/Short, nominal with CI, Flat: duration

CRVAL1

CRVAL2

CRPIX1

CRPIX2

CD1_1

CD1_2

CD2_1

CD2_2

CTYPE1

Coordinamte 1 type

CTYPE2

Coordinamte 2 type

CUNIT1

Physical units of CRVAL1

CUNIT2

Physical units of CRVAL2

WCSAXES

CMPRTSCI

Quadrant image compression ratio obtained on-board

GAIN

RDNOISE

RA

reconstructed pointing RA

DEC

reconstructed pointing DEC

PA

reconstructed position angle

EXPTIME

Commanded integration time in seconds, e.g. 565.0

SATLEVEL

pixel saturation level in e-

SATURATE

pixel saturation level in ADU

BIAS_TOP

BIAS_BTM

BIAS_LFT

BIAS_RGT

GAINCORR

ref_gain/cal_gain

BIASLVLE

BIASRONE

BIASLVLF

BIASRONF

BIASLVLG

BIASRONG

BIASLVLH

BIASRONH

LSFCORR

COSMICPC

percent of COSMIC flagged pixels in extension

STDCRMS

NUMBRMS

AVGRESID

PV1_1

PV2_1

PV1_2

PV2_2

PV1_4

PV2_4

PV1_5

PV2_5

PV1_6

PV2_6

PV1_7

PV2_7

PV1_8

PV2_8

PV1_9

PV2_9

PV1_10

PV2_10

RA_COMM

Commanding pointing RA

DEC_COMM

Commanding pointing DEC

PA_COMM

Commanding position angle

REFCAT

reference star catalogue file

FPAMODEL

MAGZEROP

zero-point

PHOT_ERR

self calibration photometric error

PHOTIRMS

self calibration mag dispersion RMS

APERCORR

self calibration aperture correction MAG_50pix - MAG_13pix

APCORRMS

self calibration aperture correction rms error

FLXSCALE

Flux scaling for stacked exposure

CCD_RA

CCD center right ascension

CCD_DEC

CCD center declination

BKG_MED

CCD bkg median value in MJY/sr

BKG_MAD

CCD bkg median absolute deviation in MJy/sr