GR1 – Pipeline and advanced data description

 

1.     Pipeline Overview.. 1

2.     Pipeline Products. 2

3.     Spectral Data Product Files. 4

4.     Source Extraction. 8

5.     Primary Object Catalog - Merged FUV+NUV Catalog (mcat file) 9

6.     Pipeline Products Gallery. 20

7.     GALEX Image Artifacts. 29

 

1.    Pipeline Overview

 

The GALEX data pipeline converts GALEX satellite telemetry data and any necessary corollary data into calibrated images, spectra, and catalogs. The GALEX Science Operations Center (SOC) receives satellite telemetry data and ingestpipe unpacks it into time-tagged photon lists, instrument/SC housekeeping, and satellite aspect information. From these data sets, orbpipe generates images, spectra, and source catalogs.

 

Astrometric modules rta (for rectify, transform and aspect) and deltaphot correct the photon positions for detector and optical distortions, and determine an aspect solution using star positions from the time-tagged photon data. The astrometric refinement process is diagrammed below.

 

 

A photometric module simplemap accumulates the photons into count and intensity maps and sextra extracts sources from images. A spectroscopic module galexspac uses image source catalog inputs to extract spectra of these sources from the multiple slitless grism observations.

 

 

2.    Pipeline Products

 

Data from each single-orbit visit stored in a single directory in the GALEX file system. The directory path has the following format:

 

<ROOT>/<proc ver>/<tile>/<obs mode>/<product>/<image>/<try>/.

 

An example path and filename is:

 

Path: <root>/01-vsn/10330-AISCHV2_381_40554/d/00-visits/0002-img/03-try/

 

Filename: AISCHV2_381_40554_0002_sv12-xd-mcat.fits

 

This path contains the pipeline processing version number, a tile identification string, instrument observing mode (direct, grism, opaque; represented by d, g, o, in each case preceded by the wavelength, data product type (single visit, multiple visit), and the pipeline processing try. Additionally, a unique source ID tag is generated by the pipeline that uniquely encodes both the path information and the source number from merged source and spectra catalogs.

 

All of the pipeline products are described in the table below.

 

Table 3.1– Pipeline Products Summary (the most significant files are in bold)     

Filename Suffix

File type

Description

Low-level pipeline products

 

Photon and housekeeping files

-asp.rec

Binary record

Satellite attitude solution. Raw S/C pointing data.

-asprta.rec

Binary record

Refined spacecraft attitude solution (using bright stars in the FOV).

-rtastar.fits

FITS binary table

Star catalog for attitude refinement: info. on stars used for S/C pointing solution vs. time.

-scst.fits

FITS binary table

Spacecraft state file: S/C status values.

Images

 

Maps and associated files

-[n or f][d or g]-cnt.fits

FITS image

Count map (J2000) in counts (photons) per pixel, corrected for image position and dither.

-[n or f][d or g]-exp.fits

FITS image

Exposure map (J2000). An image of time spent observing within the GALEX FOV (w/o response correction).

-[n or f][d or g]-intbgsub.fits

FITS image

Background-subtracted intensity map (J2000). Note: "-intbgsub" equals "-int" minus "-skybg".

-[n or f][d or g]-int.fits

FITS image

Intensity map (J2000). GALEX FOV image in counts per sec. per pixel, corrected for relative response.

-[n or f][d or g]-movie.fits

FITS image cube

Time-slice count maps (J2000). Multiple images of the raw detector within selected segments of time (not corrected for S/C motion).

-[n or f][d or g]-rr.fits

FITS image

Low resolution relative response (J2000). A low resolution version of "rrhr". (Provided only for rrhr and beyond.)

-[n or f][d or g]-skybg.fits

FITS image

Sky background image (J2000).

-[n or f][d or g]-wt.fits

FITS image

Weight/threshold image (J2000). FOV image used by Sextractor for thresholding sources. Pixels with values > 1 have a flux above the detection threshold.

Grism-specific files

 

Spectral 1-D arrays or 2-D images

-[n or f]g-gsax.fits

FITS binary table

Spectral extraction parameter information for each source

-[n or f]g-pri.fits

FITS binary table

Image strips for each source from a single visit

-[n or f]g-prc.fits

FITS binary table

Image strips (combined) for each source from multiple visits

-[n or f]g-prm.fits

FITS binary table

Image strips (median) for each source from multiple visits

-[n or f]g-gsp.fits

FITS binary table

Spectral data for each extracted source vs. wavelength

-xg-gsp.fits

FITS binary table

Spectral data for each extracted source vs. wavelength (both bands)

Quality assurance (QA)

 

QA file description

-x[d or g]-int_2color*.jpg

FITS binary table

JPEG images of the field.

*.ps

postscript text

Various postscript plots.

-[n or f]d-dphcent.txt

ASCII text

Aspect refinement QA data .

-[n or f]d-gauss*.txt

ASCII text

Gaussian filter used by Sextractor.

-[n or f]d-sexcols.txt

ASCII text

Sextractor catalog columns.

-[n or f]d-sexparams.txt

ASCII text

Parameter file used by Sextractor.

-[n or f]d-sexnnw.txt

ASCII text

Neural network parameter file used by Sextractor.

*stats.txt

ASCII text

Various QA statistics.

-[n or f]d-cat.ds9reg

ASCII text

ds9 region file: ellipses of sources listed in the -[n or f] d-c at.fits file. [Note: a ds9 region file is a file of ellipse parameters used by the image viewing program "DS9". These parameters include the RA, Dec, major and minor axes and position angle of the major axis.]

-fd-ncat.ds9reg

ASCII text

ds9 region file: ellipses of sources listed in the -fd-ncat. fit s file.

-nd-fcat.ds9reg

ASCII text

ds9 region file: ellipses of sources listed in the -nd-fcat. fit s file.

_getmask-[n or f]d-cat.ds9reg

ASCII text

ds9 region file: Objects ignored in estimating background flux.

rtastar.ds9reg

ASCII text       

ds9 region file: ellipses of bright stars from rtastar.fit s file used in the attitude solution (aspect correction).

Catalogs

 

FUV, NUV and merged catalogs

-[n or f]d-cat.fits

FITS binary table

Sextractor catalogs for images. Table of objects extracted by GALEX reduction pipeline. The table contains positions, flux, magnitude, and major/minor axes.

-[n or f]d-[f or n]cat.fits

FITS binary table

NUV (FUV) extractions using FUV (NUV) positions; the latter are taken from the FUV (NUV) source catalog "fd

-xd-mcat.fits

FITS binary table

Merged source catalog. Band-merged table of extracted objects. Contains all objects contained in "[n or f]d-cat.fits" matched to the best candidate. The table contains positions, flux, magnitude, and major/minor axes. By definition, it contains all data from the two single-band catalogs.

Flags

 

Artifact flag information

-[n or f][d or g]-flags.fits

FITS image

Artifact Flag image (J2000). Identifies predetermined regions which may introduce systematic errors in data extraction. These artifact regions are caused mainly by reflections of nearby bright stars.

-[n or f]d-flagstar.fits

FITS binary table

Star catalog for flagging. List of known bright stars used to determine artifact regions.

 

 

3.    Spectral Data Product Files

The spectral data product files are stored in binary FITS format, but they are GALEX-specific. The formats of these files are described below:

-pri.fits

This file contains the image strips for individual exposures for each spectral-extracted source. The photon data, response, and masking images are recorded for each source. Masking for the image strip is stored in the response image (neighbor masking) and the photon data image (other masking) as negative numbers. Spectral response variations with position (column) are stored in the response image in the final row. These images contain the total accumulated photon data for each source for a given single visit or exposure.

 

Each source has its own FITS header unit. The order of the image strips is identical to the order of sources in the catalog given in the (root)-gsax.fits file for those sources which are actually extracted. A catalog source is an extracted source if the "flag” column value in the -gsax.fits table is either 2 or 3.

 

First Header Unit: Includes grism position angle, total exposure time, total number of spectrally extracted sources (ECOUNT), field center, and other extraction parameters.

 

Second through “N" Header Unit: Accumulated image strips for photon data and response for any of N-1 sources in the field of view.

 

The header card portion of each of these units defines the image dimensions (PRI_NC,PRI_NR). The scale is nominally 1 arcsecond per pixel in both the spatial and dispersion directions. The header key words also include the blue limit offset in arcseconds (ARCSEC1) relative to the object center (undeviated) position, which is used to derive the wavelength scale. The image strips typically cover multiple grism orders, e.g. 1st, 2nd, and 0th. The image data is stored as 2-byte integers, which can be scaled to true data values using the header key words DATZERO, DATSCALE, RSPZERO, and RSPSCALE.

-prc.fits

This file contains the combined or summed image strips for multiple exposures for each spectral-extracted source. The format is the same as for the pri files, except that masking has been applied before summing. That is, all masked pixels in the individual (pri) image strips were set to zero before summing.

 

First Header Unit: Contains the filenames of all *-pri.fits which have been combined, their respective grism angles, observation times, spacecraft roll angles, visits, and eclipse numbers.

 

Second through "N" Header Unit: Accumulated image strips for photon data and response for any of N-1 sources in the field of view.

-prm.fits

This file contains the medianed image strips for multiple exposures for each spectral-extracted source. The format is the same as for the pri files, except that masked pixels have been ignored by the median value calculation.

 

First Header Unit: Contains the filenames of all *-pri.fits which have been medianed, as well as other information.

 

Second through "N" Header Unit: Accumulated image strips for photon data and response for any of N-1 sources in the field of view.

-gsax.fits

General information (binary FITS table). This file contains parameter information, as well as a source list table including extraction parameters for each source. This source list catalog is created on the first exposure and read in and used for each subsequent exposure. This file also contains a table of data for each accumulated exposure.

 

First Header Unit: Header key words contain various extraction parameters for ``galaxspac" (spectral accumulation program). These include the number of sources in the catalog (NUMSOURC) and the number of these sources which were actually extracted (ECOUNT); the difference is the number of sources used for masking purposes only. Also included are the field RA,Dec origin (RAO,DECO), the masking parameters, and the total exposure time accumulated (TOTTIME).

 

Second Header Unit: Extracted source list. This contains a source catalog of all the sources which have been extracted and used for masking. The table column "flag" indicates whether a source was extracted (2 or 3). The table includes the RA,Dec positions, global IDs, direct image FUV and NUV flux rates, direct image FWHMs, and extraction parameters (object and background widths and length of the spectrum) for each source.

 

Third Header Unit: Accumulated exposures (orbits) list. This contains a catalog of all the photon data sets added into the image strips. This includes all the *-pri.fits filenames, grism angles, field offsets used (x, y, twist (rotation) relative to the direct image source positions), exposure times, and reduction dates.

-xsp.fits

These are labeled *-fg-xsp.fits and *-ng-xsp.fits for each band. As in the -prc.fits and -pri.fits files, each header unit is a separate extracted source. These are "raw" spectral extractions which no flux or wavelength calibration. The units are photons per second per arcsecond. Each source has its own FITS header unit, in the same order as the data occur in the -pri.fits file.

 

First Header Unit: Contains various parameters and values.

 

Second through ``N" Header Unit: Spectra for each source and its computed Poisson error. Spectra are given in photons/second/pixel vs. offset arcsecond (which is the position relative to object center or undeviated or undispersed position).

-gsp.fits

There are three gsp files for each spectrum: *-fg-gsp, *-ng-gsp, and *-xg-gsp. The first two are calibrated spectra for NUV and FUV, rebinned onto a linear wavelength scale. The third is the conjoined spectrum of the first two files. The fg-gsp and ng-gsp files are for most purposes rendered obsolete by the xg-gsp file.

 

First Header Unit: Each file consists of a short primary header with information such as the number of spectra in the file "ECOUNT".

 

Second Header Unit: Each row of this table gives spectral information (fluxes, associated errors, etc.) for an astronomical object. These rows are listed in order of their appearance in the extracted source catalog in the (root)-gsax.fits file. However, "masking" sources appearing in the gsax file are not extracted as spectra and thus not included in the gsp file listing.

 

Two of the vector entries (obj and objerr) are for a simple (summation) extraction of the primary grism orders (1st for NUV and 2nd for FUV). Two vectors (objs and objserr) are for a summation extraction of the secondary grism orders (2nd for NUV and 3rd for FUV). One vector (objmdn) is the extraction from the median image strip (-prm.fits) and is only filled for coadded (multiple exposure) data. Finally, two vectors (opx,opxerr) are reserved for optimal extraction but are not currently used. The units for these are photons per second per centimeter squared per Angstrom. Since the dispersion is linear, the zero point and dispersion of the wavelength scale are given as table entries.

 

4.    Background Determination and Source Extraction

See Background_determination_and_source_extraction_for_GALEX_data.pdf, in the GR1 documentation.

 

 

5.      Primary Object Catalog - Merged FUV+NUV Catalog (mcat file)

The merged object catalog is the final catalog product from the GALEX data pipeline. It contains the full complement of source extractions from both the FUV and NUV images. The columns of the mcat file fall into the following major categories:

 

·        Observation description

o       Contains global object ID, pipeline version, image tile number, observation type, optics wheel position, image product type, pipeline re-run (try) number, band, mcat ID, subvisit number and leg number (where applicable)

·        Band merger output quantities and flags

o       Includes merged position in Equatorial and Galactic coordinates, extinction E(B-V) from Schlegel maps, and calibrated fluxes, magnitudes and errors. “Calibrated” currently means that values have been converted to AB magnitudes. Four additional columns contain FUV fluxes extracted at NUV detection positions, NUV fluxes extracted at FUV detection positions and their errors. These are useful for any study that is best performed using identical aperture photometry in each band (e.g. for colors, photometric redshifts)

·        Neighbor properties

o       Includes neighbor count and total flux out to three radii (currently set to 5”, 10” and 30”), closest neighbor distance, PA and nuv and fuv mag.

·        Derived quantities and map levels at merged output position

o       Includes extractions from pipeline-generated maps at the position of the detected source. Sky background [counts s-1 pixel-1], artifact [flag value], weight [exposure-relative response product], contrast [dimensionless] and masked pixel counts [number] values are given for each source.

·        Sextractor output columns from FUV image extractions

·        Sextractor output columns from NUV image extractions

o       Please consult the Sextractor manual and Sextractor for Dummies for definitions of these outputs

 

Catalog Fields

 

Table 3.2 Merged Object Catalog (-xd-mcat.fits). For more detailed descriptions of the first 85 columns, see GR1_Column_descriptions_for_-xd-mcat.fits.htm in the GR1 documentation.

Name

Col

Format

Unit

Definition

Object ID and orbpipe info

 

 

 

 

ggoid_hex

1

16A

string

Hex string of Galex Global Object ID

ggoid_dec

2

20A

string

Decimal string of Galex Global Object ID

ggoid

3

2J

number

Galex Global Object ID

vsn

4

1J

number

Version number

tilenum

5

1J

number

Tile number

type

6

1J

number

Obs.type (0=single,1=multi)

ow

7

1J

number

Optics wheel (1=drct,2=grsm,3=opaq)

prod

8

1J

number

Product number (_visits,_main,etc.)

img

9

1J

number

image number (exposure# for _visits)

try

10

1J

number

Try number (processing attempt number)

band

11

1J

number

Band number (1=nuv,2=fuv,3=both)

id

12

1J

number

Merged ID.

subvisit

13

1I

number

Sub-visit number for AIS

leg

14

1I

number

Planned leg number for AIS

Merged object quantities

 

 

 

 

alpha_j2000

15

1D

degrees

Merged Right Ascension(degrees).

delta_j2000

16

1D

degrees

Merged Declination (degrees).

prob

17

1E

probability

Chi-squared probability of match.

sep

18

1E

arcseconds

Separation between band positions.

E_bv

19

1E

number

E(B-V) Galactic Reddening.

glon

20

1E

degrees

Galactic longitude in degrees.

glat

21

1E

degrees

Galactic latitude in degrees.

primary

22

1J

number

Primary source flag

fov_radius

23

1E

degrees

distance from center of FOV in degrees

nuv_det_x

24

1E

value

NUV detector X position

nuv_det_y

25

1E

value

NUV detector Y position

fuv_det_x

26

1E

value

FUV detector X position

fuv_det_y

27

1E

value

FUV detector Y position

chkobj_type

28

1J

number

Astrometry check type

chkobj_id

29

1J

number

Astrometry check ID

chkobj_r

30

1E

degrees

Astrometry check radius in degrees

chkobj_pa

31

1E

degrees

Astrometry check position angle in degrees

misc_flags

32

1J

value

Miscellaneous flags

nuv_flux

33

1E

flux

NUV calibrated flux (micro Jansky)

nuv_fluxerr

34

1E

flux

NUV calibrated flux error

nuv_mag

35

1E

mag

NUV calibrated magnitude

nuv_magerr

36

1E

mag

NUV calibrated magnitude error

fuv_flux

37

1E

flux

FUV calibrated flux (micro Jansky)

fuv_fluxerr

38

1E

flux

FUV calibrated flux error

fuv_mag

39

1E

mag

FUV calibrated magnitude

fuv_magerr

40

1E

mag

FUV calibrated magnitude error

nuv_fcat_flux

41

1E

flux

NUV calibrated flux using FUV catalog position

nuv_fcat_fluxerr

42

1E

flux

Error for nuv_fcat_flux

fuv_ncat_flux

43

1E

flux

FUV calibrated flux using NUV catalog position

fuv_ncat_fluxerr

44

1E

flux

Error for fuv_ncat_flux

Nearest neighbor

 

 

 

 

nuv_nc_r1

45

1I

number

NUV neighbor count out to radius R1

nuv_nc_r2

46

1I

number

NUV neighbor count out to radius R2

nuv_nc_r3

47

1I

number

NUV neighbor count out to radius R3

fuv_nc_r1

48

1I

number

FUV neighbor count out to radius R1

fuv_nc_r2

49

1I

number

FUV neighbor count out to radius R2

fuv_nc_r3

50

1I

number

FUV neighbor count out to radius R3

nuv_nf_r1

51

1E

flux

NUV neighbor flux out to radius R1

nuv_nf_r2

52

1E

flux

NUV neighbor flux out to radius R2

nuv_nf_r3

53

1E

flux

NUV neighbor flux out to radius R3

fuv_nf_r1

54

1E

flux

FUV neighbor flux out to radius R1

fuv_nf_r2

55

1E

flux

FUV neighbor flux out to radius R2

fuv_nf_r3

56

1E

flux

FUV neighbor flux out to radius R3

cn_radius

57

1E

arcseconds

Closest neighbor radius in arcseconds

cn_pa

58

1E

degrees

Closest neighbor position angle in degrees

cn_mag_nuv

59

1E

mag

Closest neighbor NUV magnitude

cn_mag_fuv

60

1E

mag

Closest neighbor FUV magnitude

Image/detection map values

 

 

 

 

nuv_skybg

61

1E

flux

NUV sky background (photons/sec/sq.arcsec) (at

fuv_skybg

62

1E

flux

FUV sky background (photons/sec/sq.arcsec) (at

nuv_weight

63

1E

seconds

NUV effective exposure (response) (mdn near sou

fuv_weight

64

1E

seconds

FUV effective exposure (response) (mdn near sou

nuv_thres

65

1E

sigmas

NUV threshold sigmas (int-bg)/wt)

fuv_thres

66

1E

sigmas

FUV threshold sigmas (int-bg)/wt)

nuv_contrast

67

1E

ratio

NUV ratio of min to max response near source

fuv_contrast

68

1E

ratio

FUV ratio of min to max response near source

nuv_maskpix

69

1J

number

NUV number of masked pixels near source

fuv_maskpix

70

1J

number

FUV number of masked pixels near source

nuv_artifact

71

1J

number

NUV artifact flag (logical OR near source)

fuv_artifact

72

1J

number

FUV artifact flag (logical OR near source)

Band merger QA

 

 

 

 

nuv_ambg

73

1J

number

NUV ambiguity flag.

fuv_ambg

74

1J

number

FUV ambiguity flag.

nuv_nc

75

1J

number

NUV number of candidates.

fuv_nc

76

1J

number

FUV number of candidates.

nuv_cid1

77

1J

number

First candidate for NUV source(FUV IDs)

fuv_cid1

78

1J

number

First candidate for FUV source(NUV IDs)

nuv_cid2

79

1J

number

Second candidate for NUV source(FUV IDs)

fuv_cid2

80

1J

number

Second candidate for FUV source(NUV IDs)

nuv_cid3

81

1J

number

Third candidate for NUV source(FUV IDs)

fuv_cid3

82

1J

number

Third candidate for FUV source(NUV IDs)

sourcepa

83

1E

degrees

position angle betw. band sources.

objtype

84

1J

number

0=galaxy,1=star,-1=unknown, etc.

quality

85

1J

number

Quality flag (undefined)

NUV source extraction catalog

 

 

 

 

NUV_NUMBER

86

1J

value

Running object number

NUV_FLUX_ISO

87

1E

flux

Isophotal flux

NUV_FLUXERR_ISO

88

1E

flux

RMS error for isophotal flux

NUV_MAG_ISO

89

1E

mag

Isophotal magnitude

NUV_MAGERR_ISO

90

1E

mag

RMS error for isophotal magnitude

NUV_FLUX_ISOCOR

91

1E

flux

Corrected isophotal flux

NUV_FLUXERR_ISOCOR

92

1E

flux

RMS error for corrected isophotal flux

NUV_MAG_ISOCOR

93

1E

mag

Corrected isophotal magnitude

NUV_MAGERR_ISOCOR

94

1E

mag

RMS error for corrected isophotal magnitude

NUV_FLUX_APER_1

95

1E

flux

Flux aperture (   2.000)

NUV_FLUX_APER_2

96

1E

flux

Flux aperture (   3.000)

NUV_FLUX_APER_3

97

1E

flux

Flux aperture (   5.000)

NUV_FLUX_APER_4

98

1E

flux

Flux aperture (   8.000)

NUV_FLUX_APER_5

99

1E

flux

Flux aperture (  12.000)

NUV_FLUX_APER_6

100

1E

flux

Flux aperture (  17.000)

NUV_FLUX_APER_7

101

1E

flux

Flux aperture (  23.000)

NUV_FLUXERR_APER_1

102

1E

flux

Flux error aperture (   2.000)

NUV_FLUXERR_APER_2

103

1E

flux

Flux error aperture (   3.000)

NUV_FLUXERR_APER_3

104

1E

flux

Flux error aperture (   5.000)

NUV_FLUXERR_APER_4

105

1E

flux

Flux error aperture (   8.000)

NUV_FLUXERR_APER_5

106

1E

flux

Flux error aperture (  12.000)

NUV_FLUXERR_APER_6

107

1E

flux

Flux error aperture (  17.000)

NUV_FLUXERR_APER_7

108

1E

flux

Flux error aperture (  23.000)

NUV_MAG_APER_1

109

1E

mag

Magnitude aperture (   2.000)

NUV_MAG_APER_2

110

1E

mag

Magnitude aperture (   3.000)

NUV_MAG_APER_3

111

1E

mag

Magnitude aperture (   5.000)

NUV_MAG_APER_4

112

1E

mag

Magnitude aperture (   8.000)

NUV_MAG_APER_5

113

1E

mag

Magnitude aperture (  12.000)

NUV_MAG_APER_6

114

1E

mag

Magnitude aperture (  17.000)

NUV_MAG_APER_7

115

1E

mag

Magnitude aperture (  23.000)

NUV_MAGERR_APER_1

116

1E

mag

Magnitude error aperture (   2.000)

NUV_MAGERR_APER_2

117

1E

mag

Magnitude error aperture (   3.000)

NUV_MAGERR_APER_3

118

1E

mag

Magnitude error aperture (   5.000)

NUV_MAGERR_APER_4

119

1E

mag

Magnitude error aperture (   8.000)

NUV_MAGERR_APER_5

120

1E

mag

Magnitude error aperture (  12.000)

NUV_MAGERR_APER_6

121

1E

mag

Magnitude error aperture (  17.000)

NUV_MAGERR_APER_7

122

1E

mag

Magnitude error aperture (  23.000)

NUV_FLUX_AUTO

123

1E

flux

Flux within a Kron-like elliptical aperture

NUV_FLUXERR_AUTO

124

1E

flux

RMS error for AUTO flux

NUV_MAG_AUTO

125

1E

mag

Kron-like elliptical aperture magnitude

NUV_MAGERR_AUTO

126

1E

mag

RMS error for AUTO magnitude

NUV_FLUX_BEST

127

1E

flux

Best of FLUX_AUTO and FLUX_ISOCOR

NUV_FLUXERR_BEST

128

1E

flux

RMS error for BEST flux

NUV_MAG_BEST

129

1E

mag

Best of MAG_AUTO and MAG_ISOCOR

NUV_MAGERR_BEST

130

1E

mag

RMS error for MAG_BEST

NUV_FLUX_RADIUS_1

131

1E

pixel

Fraction-of-light radius (  0.2000)

NUV_FLUX_RADIUS_2

132

1E

pixel

Fraction-of-light radius (  0.5000)

NUV_FLUX_RADIUS_3

133

1E

pixel

Fraction-of-light radius (  0.8000)

NUV_FLUX_RADIUS_4

134

1E

pixel

Fraction-of-light radius (  0.9000)

NUV_FLUX_RADIUS_5

135

1E

pixel

Fraction-of-light radius (  0.9500)

NUV_ZPMAG

136

1E

mag

NUV zero point magnitude correction.

NUV_KRON_RADIUS

137

1E

pixel

Kron apertures in units of A or B

NUV_BACKGROUND

138

1E

count

Background at centroid position

NUV_THRESHOLD

139

1E

number

Detection threshold above background

NUV_MU_THRESHOLD

140

1E

number

Detection threshold above background

NUV_FLUX_MAX

141

1E

number

Peak flux above background

NUV_MU_MAX

142

1E

number

Peak surface brightness above background

NUV_ISOAREA_IMAGE

143

1E

number

Isophotal area above Analysis threshold

NUV_ISOAREA_WORLD

144

1E

number

Isophotal area above Analysis threshold

NUV_XMIN_IMAGE

145

1J

pixel

Minimum x-coordinate among detected pixels

NUV_YMIN_IMAGE

146

1J

pixel

Minimum y-coordinate among detected pixels

NUV_XMAX_IMAGE

147

1J

pixel

Maximum x-coordinate among detected pixels

NUV_YMAX_IMAGE

148

1J

pixel

Maximum y-coordinate among detected pixels

NUV_X_IMAGE

149

1E

pixel

Object position along x

NUV_Y_IMAGE

150

1E

pixel

Object position along y

NUV_XPEAK_IMAGE

151

1J

count

x-coordinate of the brightest pixel

NUV_YPEAK_IMAGE

152

1J

count

y-coordinate of the brightest pixel

NUV_ALPHA_J2000

153

1D

degrees

Right ascension of barycenter (J2000)

NUV_DELTA_J2000

154

1D

degrees

Declination of barycenter (J2000)

NUV_X2_IMAGE

155

1E

pixel

Variance along x

NUV_Y2_IMAGE

156

1E

pixel

Variance along y

NUV_XY_IMAGE

157

1E

pixel

Covariance between x and y

NUV_X2_WORLD

158

1E

number

Variance along X-WORLD (alpha)

NUV_Y2_WORLD

159

1E

number

Variance along Y-WORLD (delta)

NUV_XY_WORLD

160

1E

number

Covariance between X-WORLD and Y-WORLD

NUV_CXX_IMAGE

161

1E

number

Cxx object ellipse parameter

NUV_CYY_IMAGE

162

1E

number

Cyy object ellipse parameter

NUV_CXY_IMAGE

163

1E

number

Cxy object ellipse parameter

NUV_CXX_WORLD

164

1E

number

Cxx object ellipse parameter (WORLD units)

NUV_CYY_WORLD

165

1E

number

Cyy object ellipse parameter (WORLD units)

NUV_CXY_WORLD

166

1E

number

Cxy object ellipse parameter (WORLD units)

NUV_A_IMAGE

167

1E

number

Profile RMS along major axis

NUV_B_IMAGE

168

1E

number

Profile RMS along minor axis

NUV_A_WORLD

169

1E

number

Profile RMS along major axis (world units)

NUV_B_WORLD

170

1E

number

Profile RMS along minor axis (world units)

NUV_THETA_IMAGE

171

1E

degrees

Position angle (CCW/x)

NUV_THETA_WORLD

172

1E

degrees

Position angle (CCW/world-x)

NUV_THETA_J2000

173

1E

degrees

Position angle (east of north) (J2000)

NUV_ELONGATION

174

1E

number

A_IMAGE/B_IMAGE

NUV_ELLIPTICITY

175

1E

number

1 - B_IMAGE/A_IMAGE

NUV_ERRX2_IMAGE

176

1D

number

Variance of position along x

NUV_ERRY2_IMAGE

177

1D

number

Variance of position along y

NUV_ERRXY_IMAGE

178

1E

number

Covariance of position between x and y

NUV_ERRX2_WORLD

179

1D

number

Variance of position along X-WORLD (alpha)

NUV_ERRY2_WORLD

180

1D

number

Variance of position along Y-WORLD (delta)

NUV_ERRXY_WORLD

181

1E

number

Covariance of position X-WORLD/Y-WORLD

NUV_ERRCXX_IMAGE

182

1E

number

Cxx error ellipse parameter

NUV_ERRCYY_IMAGE

183

1E

number

Cyy error ellipse parameter

NUV_ERRCXY_IMAGE

184

1E

number

Cxy error ellipse parameter

NUV_ERRCXX_WORLD

185

1E

number

Cxx error ellipse parameter (WORLD units)

NUV_ERRCYY_WORLD

186

1E

number

Cyy error ellipse parameter (WORLD units)

NUV_ERRCXY_WORLD

187

1E

number

Cxy error ellipse parameter (WORLD units)

NUV_ERRA_IMAGE

188

1E

number

RMS position error along major axis

NUV_ERRB_IMAGE

189

1E

number

RMS position error along minor axis

NUV_ERRA_WORLD

190

1E

number

World RMS position error along major axis

NUV_ERRB_WORLD

191

1E

number

World RMS position error along minor axis

NUV_ERRTHETA_IMAGE

192

1E

number

Error ellipse position angle (CCW/x)

NUV_ERRTHETA_WORLD

193

1E

number

Error ellipse pos. angle (CCW/world-x)

NUV_ERRTHETA_J2000

194

1E

number

J2000 error ellipse pos. angle (east of north)

NUV_FWHM_IMAGE

195

1E

pixel

FWHM assuming a gaussian core

NUV_FWHM_WORLD

196

1E

deg

FWHM assuming a gaussian core

NUV_FLAGS

197

1I

value

Extraction flags

NUV_CLASS_STAR

198

1E

value

S/G classifier output

FUV source extraction catalog

 

 

 

 

FUV_NUMBER

199

1J

value

Running object number

FUV_FLUX_ISO

200

1E

flux

Isophotal flux

FUV_FLUXERR_ISO

201

1E

flux

RMS error for isophotal flux

FUV_MAG_ISO

202

1E

mag

Isophotal magnitude

FUV_MAGERR_ISO

203

1E

mag

RMS error for isophotal magnitude

FUV_FLUX_ISOCOR

204

1E

flux

Corrected isophotal flux

FUV_FLUXERR_ISOCOR

205

1E

flux

RMS error for corrected isophotal flux

FUV_MAG_ISOCOR

206

1E

mag

Corrected isophotal magnitude

FUV_MAGERR_ISOCOR

207

1E

mag

RMS error for corrected isophotal magnitude

FUV_FLUX_APER_1

208

1E

flux

Flux aperture (   2.000)

FUV_FLUX_APER_2

209

1E

flux

Flux aperture (   3.000)

FUV_FLUX_APER_3

210

1E

flux

Flux aperture (   5.000)

FUV_FLUX_APER_4

211

1E

flux

Flux aperture (   8.000)

FUV_FLUX_APER_5

212

1E

flux

Flux aperture (  12.000)

FUV_FLUX_APER_6

213

1E

flux

Flux aperture (  17.000)

FUV_FLUX_APER_7

214

1E

flux

Flux aperture (  23.000)

FUV_FLUXERR_APER_1

215

1E

flux

Flux error aperture (   2.000)

FUV_FLUXERR_APER_2

216

1E

flux

Flux error aperture (   3.000)

FUV_FLUXERR_APER_3

217

1E

flux

Flux error aperture (   5.000)

FUV_FLUXERR_APER_4

218

1E

flux

Flux error aperture (   8.000)

FUV_FLUXERR_APER_5

219

1E

flux

Flux error aperture (  12.000)

FUV_FLUXERR_APER_6

220

1E

flux

Flux error aperture (  17.000)

FUV_FLUXERR_APER_7

221

1E

flux

Flux error aperture (  23.000)

FUV_MAG_APER_1

222

1E

mag

Magnitude aperture (   2.000)

FUV_MAG_APER_2

223

1E

mag

Magnitude aperture (   3.000)

FUV_MAG_APER_3

224

1E

mag

Magnitude aperture (   5.000)

FUV_MAG_APER_4

225

1E

mag

Magnitude aperture (   8.000)

FUV_MAG_APER_5

226

1E

mag

Magnitude aperture (  12.000)

FUV_MAG_APER_6

227

1E

mag

Magnitude aperture (  17.000)

FUV_MAG_APER_7

228

1E

mag

Magnitude aperture (  23.000)

FUV_MAGERR_APER_1

229

1E

mag

Magnitude error aperture (   2.000)

FUV_MAGERR_APER_2

230

1E

mag

Magnitude error aperture (   3.000)

FUV_MAGERR_APER_3

231

1E

mag

Magnitude error aperture (   5.000)

FUV_MAGERR_APER_4

232

1E

mag

Magnitude error aperture (   8.000)

FUV_MAGERR_APER_5

233

1E

mag

Magnitude error aperture (  12.000)

FUV_MAGERR_APER_6

234

1E

mag

Magnitude error aperture (  17.000)

FUV_MAGERR_APER_7

235

1E

mag

Magnitude error aperture (  23.000)

FUV_FLUX_AUTO

236

1E

flux

Flux within a Kron-like elliptical aperture

FUV_FLUXERR_AUTO

237

1E

flux

RMS error for AUTO flux

FUV_MAG_AUTO

238

1E

mag

Kron-like elliptical aperture magnitude

FUV_MAGERR_AUTO

239

1E

mag

RMS error for AUTO magnitude

FUV_FLUX_BEST

240

1E

flux

Best of FLUX_AUTO and FLUX_ISOCOR

FUV_FLUXERR_BEST

241

1E

flux

RMS error for BEST flux

FUV_MAG_BEST

242

1E

mag

Best of MAG_AUTO and MAG_ISOCOR

FUV_MAGERR_BEST

243

1E

mag

RMS error for MAG_BEST

FUV_FLUX_RADIUS_1

244

1E

pixel

Fraction-of-light radius (  0.2000)

FUV_FLUX_RADIUS_2

245

1E

pixel

Fraction-of-light radius (  0.5000)

FUV_FLUX_RADIUS_3

246

1E

pixel

Fraction-of-light radius (  0.8000)

FUV_FLUX_RADIUS_4

247

1E

pixel

Fraction-of-light radius (  0.9000)

FUV_FLUX_RADIUS_5

248

1E

pixel

Fraction-of-light radius (  0.9500)

FUV_ZPMAG

249

1E

mag

FUV zero point magnitude correction.

FUV_KRON_RADIUS

250

1E

pixel

Kron apertures in units of A or B

FUV_BACKGROUND

251

1E

count

Background at centroid position

FUV_THRESHOLD

252

1E

number

Detection threshold above background

FUV_MU_THRESHOLD

253

1E

number

Detection threshold above background

FUV_FLUX_MAX

254

1E

number

Peak flux above background

FUV_MU_MAX

255

1E

number

Peak surface brightness above background

FUV_ISOAREA_IMAGE

256

1E

number

Isophotal area above Analysis threshold

FUV_ISOAREA_WORLD

257

1E

number

Isophotal area above Analysis threshold

FUV_XMIN_IMAGE

258

1J

pixel

Minimum x-coordinate among detected pixels

FUV_YMIN_IMAGE

259

1J

pixel

Minimum y-coordinate among detected pixels

FUV_XMAX_IMAGE

260

1J

pixel

Maximum x-coordinate among detected pixels

FUV_YMAX_IMAGE

261

1J

pixel

Maximum y-coordinate among detected pixels

FUV_X_IMAGE

262

1E

pixel

Object position along x

FUV_Y_IMAGE

263

1E

pixel

Object position along y

FUV_XPEAK_IMAGE

264

1J

count

x-coordinate of the brightest pixel

FUV_YPEAK_IMAGE

265

1J

count

y-coordinate of the brightest pixel

FUV_ALPHA_J2000

266

1D

degrees

Right ascension of barycenter (J2000)

FUV_DELTA_J2000

267

1D

degrees

Declination of barycenter (J2000)

FUV_X2_IMAGE

268

1E

pixel

Variance along x

FUV_Y2_IMAGE

269

1E

pixel

Variance along y

FUV_XY_IMAGE

270

1E

pixel

Covariance between x and y

FUV_X2_WORLD

271

1E

number

Variance along X-WORLD (alpha)

FUV_Y2_WORLD

272

1E

number

Variance along Y-WORLD (delta)

FUV_XY_WORLD

273

1E

number

Covariance between X-WORLD and Y-WORLD

FUV_CXX_IMAGE

274

1E

number

Cxx object ellipse parameter

FUV_CYY_IMAGE

275

1E

number

Cyy object ellipse parameter

FUV_CXY_IMAGE

276

1E

number

Cxy object ellipse parameter

FUV_CXX_WORLD

277

1E

number

Cxx object ellipse parameter (WORLD units)

FUV_CYY_WORLD

278

1E

number

Cyy object ellipse parameter (WORLD units)

FUV_CXY_WORLD

279

1E

number

Cxy object ellipse parameter (WORLD units)

FUV_A_IMAGE

280

1E

number

Profile RMS along major axis

FUV_B_IMAGE

281

1E

number

Profile RMS along minor axis

FUV_A_WORLD

282

1E

number

Profile RMS along major axis (world units)

FUV_B_WORLD

283

1E

number

Profile RMS along minor axis (world units)

FUV_THETA_IMAGE

284

1E

degrees

Position angle (CCW/x)

FUV_THETA_WORLD

285

1E

degrees

Position angle (CCW/world-x)

FUV_THETA_J2000

286

1E

degrees

Position angle (east of north) (J2000)

FUV_ELONGATION

287

1E

number

A_IMAGE/B_IMAGE

FUV_ELLIPTICITY

288

1E

number

1 - B_IMAGE/A_IMAGE

FUV_ERRX2_IMAGE

289

1D

number

Variance of position along x

FUV_ERRY2_IMAGE

290

1D

number

Variance of position along y

FUV_ERRXY_IMAGE

291

1E

number

Covariance of position between x and y

FUV_ERRX2_WORLD

292

1D

number

Variance of position along X-WORLD (alpha)

FUV_ERRY2_WORLD

293

1D

number

Variance of position along Y-WORLD (delta)

FUV_ERRXY_WORLD

294

1E

number

Covariance of position X-WORLD/Y-WORLD

FUV_ERRCXX_IMAGE

295

1E

number

Cxx error ellipse parameter

FUV_ERRCYY_IMAGE

296

1E

number

Cyy error ellipse parameter

FUV_ERRCXY_IMAGE

297

1E

number

Cxy error ellipse parameter

FUV_ERRCXX_WORLD

298

1E

number

Cxx error ellipse parameter (WORLD units)

FUV_ERRCYY_WORLD

299

1E

number

Cyy error ellipse parameter (WORLD units)

FUV_ERRCXY_WORLD

300

1E

number

Cxy error ellipse parameter (WORLD units)

FUV_ERRA_IMAGE

301

1E

number

RMS position error along major axis

FUV_ERRB_IMAGE

302

1E

number

RMS position error along minor axis

FUV_ERRA_WORLD

303

1E

number

World RMS position error along major axis

FUV_ERRB_WORLD

304

1E

number

World RMS position error along minor axis

FUV_ERRTHETA_IMAGE

305

1E

number

Error ellipse position angle (CCW/x)

FUV_ERRTHETA_WORLD

306

1E

number

Error ellipse pos. angle (CCW/world-x)

FUV_ERRTHETA_J2000

307

1E

number

J2000 error ellipse pos. angle (east of north)

FUV_FWHM_IMAGE

308

1E

pixel

FWHM assuming a gaussian core

FUV_FWHM_WORLD

309

1E

deg

FWHM assuming a gaussian core

FUV_FLAGS

310

1I

value

Extraction flags

FUV_CLASS_STAR

311

1E

value

S/G classifier output

 

Primary Header Card for mcat.fits file

 

FITS Preamble

 

SIMPLE  =                    T / file does conform to FITS standard

BITPIX  =                   16 / number of bits per data pixel

NAXIS   =                    0 / number of data axes

EXTEND  =                    T / FITS dataset may contain extensions

COMMENT   FITS (Flexible Image Transport System) format is defined in 'Astronomy

COMMENT   and Astrophysics', volume 376, page 359; bibcode: 2001A&A...376..359H

ORIGIN  = 'galexmerge.c'

 

Band Merger Input Files

 

NUVFILE = '/home/runes5/fltops/pipe/01-vsn/06051-CDFS_00/d/01-main/0001-img/04&'

CONTINUE  '-try/CDFS_00-nd-cat.fits' / NUV source catalog file.

FUVFILE = '/home/runes5/fltops/pipe/01-vsn/06051-CDFS_00/d/01-main/0001-img/04&'

CONTINUE  '-try/CDFS_00-fd-cat.fits' / FUV source catalog file.

NUVWTFIL= '/home/runes5/fltops/pipe/01-vsn/06051-CDFS_00/d/01-main/0001-img/04&'

CONTINUE  '-try/CDFS_00-nd-rrhr.fits' / NUV weight image file.

FUVWTFIL= '/home/runes5/fltops/pipe/01-vsn/06051-CDFS_00/d/01-main/0001-img/04&'

CONTINUE  '-try/CDFS_00-fd-rrhr.fits' / FUV weight image file.

NUVCNTFI= '/home/runes5/fltops/pipe/01-vsn/06051-CDFS_00/d/01-main/0001-img/04&'

CONTINUE  '-try/CDFS_00-nd-cnt.fits' / NUV count image file.

FUVCNTFI= '/home/runes5/fltops/pipe/01-vsn/06051-CDFS_00/d/01-main/0001-img/04&'

CONTINUE  '-try/CDFS_00-fd-cnt.fits' / FUV count image file.

NUVINTFI= '/home/runes5/fltops/pipe/01-vsn/06051-CDFS_00/d/01-main/0001-img/04&'

CONTINUE  '-try/CDFS_00-nd-int.fits' / NUV intensity image file.

FUVINTFI= '/home/runes5/fltops/pipe/01-vsn/06051-CDFS_00/d/01-main/0001-img/04&'

CONTINUE  '-try/CDFS_00-fd-int.fits' / FUV intensity image file.

NUVLWTFI= '/home/runes5/fltops/pipe/01-vsn/06051-CDFS_00/d/01-main/0001-img/04&'

CONTINUE  '-try/CDFS_00-nd-wt.fits' / NUV literal weight (-wt.fits) file.

FUVLWTFI= '/home/runes5/fltops/pipe/01-vsn/06051-CDFS_00/d/01-main/0001-img/04&'

CONTINUE  '-try/CDFS_00-fd-wt.fits' / FUV literal weight (-wt.fits) file.

NUVSKYFI= '/home/runes5/fltops/pipe/01-vsn/06051-CDFS_00/d/01-main/0001-img/04&'

CONTINUE  '-try/CDFS_00-nd-skybg.fits' / NUV sky background image file.

FUVSKYFI= '/home/runes5/fltops/pipe/01-vsn/06051-CDFS_00/d/01-main/0001-img/04&'

CONTINUE  '-try/CDFS_00-fd-skybg.fits' / FUV sky background image file.

NUVFLGFI= '/home/runes5/fltops/pipe/01-vsn/06051-CDFS_00/d/01-main/0001-img/04&'

CONTINUE  '-try/CDFS_00-nd-flags.fits' / NUV artifact flags image file.

FUVFLGFI= '/home/runes5/fltops/pipe/01-vsn/06051-CDFS_00/d/01-main/0001-img/04&'

CONTINUE  '-try/CDFS_00-fd-flags.fits' / FUV artifact flags image file.

MCHFILE = '/home/runes5/fltops/pipe/01-vsn/06051-CDFS_00/d/01-main/0001-img/04&'

CONTINUE  '-try/CDFS_00-nd-cat_mch_rtastar.fits' / RTA star match file.

STARCAT = '/home/runes5/fltops/pipe/01-vsn/06051-CDFS_00/d/01-main/0001-img/04&'

CONTINUE  '-try/CDFS_00-rtastar.fits'

 

RTA (Rectification, Transformation, and Aspect correction) values

 

NSTAR   =                   30

NMCH    =                   30

RMEAN   =    0.536157456361519

RMEANSD =   0.0510420409592596

RSTDDEV =    0.279568772144891

RMIN    =     0.13556304962726

RMAX    =      1.1818926138633

 

Band Merger Parameters and Output Quantities

 

NUVS2N  =                   2. / Minimum S/N for NUV merges.

FUVS2N  =                   2. / Minimum S/N for FUV merges.

NUVS2NCU=                   0. / S/N Cutoff for any NUV sources.

FUVS2NCU=                   0. / S/N Cutoff for any FUV sources.

NUVNUM  =                29869 / Number of NUV sources.

FUVNUM  =                16377 / Number of FUV sources.

SEPLIM  =                   7. / Maximum separation in arcsec.

PROBLIM =                   0. / Minimum probability for matches.

RPOSERR =    0.962917339842493 / Radial position error.

RA_CENT =            53.127785 / RA center for this field.

DEC_CENT=           -27.871367 / DEC center for this field.

RAO     =            53.127785 / RA center for this field.

DECO    =           -27.871367 / DEC center for this field.

TOTNUM  =                33542 / Total number of sources.

TOTFILL =                12704 / Number of filled sources.

TOTUFN  =                17165 / Number of unfilled NUV sources.

TOTUFF  =                 3673 / Number of unfilled FUV sources.

LRGNUVID=                29870 / Largest NUV ID number plus one.

N_ZPMAG =     20.0823753525469 / NUV Zero Point Magnitude

F_ZPMAG =     18.8170737879193 / FUV Zero Point Magnitude

N_ZPSCAL=                   1. / NUV Zero Point Scale Factor

F_ZPSCAL=                   1. / FUV Zero Point Scale Factor

CALMAG  = 'AUTO    '           / Calibration magnitude type

N_CUJ   =     33.6539993286133 / NUV scale: pho/sec to micro Janskys

F_CUJ   =      107.93399810791 / FUV scale: pho/sec to micro Janskys

R1      =                   5. / Neighbor radius limit 1 (arcsec)

R2      =                  10. / Neighbor radius limit 2 (arcsec)

R3      =                  30. / Neighbor radius limit 3 (arcsec)

N_AMBG0 =                17063 / Number of NUV 0 ambig.

N_AMBG1 =                12704 / Number of NUV 1 ambig.

N_AMBG2 =                    0 / Number of NUV 2 ambig.

N_AMBG3 =                  102 / Number of NUV 3 ambig.

N_AMBG4 =                    0 / Number of NUV 4 ambig.

N_AMBG5 =                    0 / Number of NUV 5 ambig.

N_AMBG6 =                    0 / Number of NUV 6 ambig.

N_AMBGM6=                    0 / Number of NUV -6 ambig.

N_AMBGM1=                    0 / Number of NUV -1 ambig.

F_AMBG0 =                 3521 / Number of FUV 0 ambig.

F_AMBG1 =                12704 / Number of FUV 1 ambig.

F_AMBG2 =                    0 / Number of FUV 2 ambig.

F_AMBG3 =                  152 / Number of FUV 3 ambig.

F_AMBG4 =                    0 / Number of FUV 4 ambig.

F_AMBG5 =                    0 / Number of FUV 5 ambig.

F_AMBG6 =                    0 / Number of FUV 6 ambig.

F_AMBGM6=                    0 / Number of FUV -6 ambig.

F_AMBGM1=                    0 / Number of FUV -1 ambig.

COMMENT AMBG  0: unfilled, no candidates, no ambiguity.

COMMENT AMBG  1: filled, first choice candidates agree, no ambiguity.

COMMENT AMBG  2: filled, first choice matches second choice candidate.

COMMENT AMBG  3: unfilled, first choice taken, no second choice candidate.

COMMENT AMBG  4: filled, second choice matches a first choice candidate.

COMMENT AMBG  5: filled, second choice matches a second choice candidate.

COMMENT AMBG  6: unfilled, first and second taken, no third choice.

COMMENT AMBG -6: unfilled, first and second taken, third choice exists.

COMMENT AMBG -1: unfilled, cleared, unchecked.

COMMENT AMBG -2: not applicable, does not exist, blank.

FILENAME= '/home/runes5/fltops/pipe/01-vsn/06051-CDFS_00/d/01-main/0001-img/04&'

CONTINUE  '-try/CDFS_00-xd-mcat.fits'

DIRECTRY= '/home/runes5/fltops/pipe/01-vsn/06051-CDFS_00/d/01-main/0001-img/04&'

CONTINUE  '-try/   '

VSN     =                    1 / Reduction version (high level)

TILENUM =                 6051 / Tile number (a.k.a. field or target)

TYPE    =                    0 / Observation type (0=single,1=multi)

OW      =                    1 / Optics wheel (1=drct,2=grsm,3=opaq)

PROD    =                    1 / Reduction product number (type)

IMG     =                    1 / Image number (exposure or run)

TRY     =                    4 / Reduction try number (low level)

 

Common header cards from SExtractor (Source Extractor) Output

 

EPOCH   =                2000.

OBJECT  = 'CDFS_00_0037'

CRVAL1  =            53.127785

CRVAL2  =           -27.871367

CRPIX1  =               1920.5

CRPIX2  =               1920.5

CDELT1  = -0.000416666666666667

CDELT2  = 0.000416666666666667

CROTA1  =                   0.

CROTA2  =                   0.

GRELEASE= 'ops-v4_0-RC2'

EQUINOX =                2000.

ECLIPSE =                 -999

LEG     =                 -999

MPSNPOS =                    0

VISIT   =                   -1

SUBVIS  =                    0

ROLL    =                -999.

OBS-DATE= '2003-11-09'

OBSDATIM= 'unknown '

TILENAME= 'CDFS_00 '

PLANID  =                   -1

MPSPHASE= 'G1      '

MPSPLAN = 'deep    '

MPSTYPE = 'DIS     '

AVASPRA =     53.1298646069532

AVASPDEC=    -27.8761034951757

AVASPROL=     203.961542187749

AVASPOK =                -999.

 

Aperture information for flux aperture columns

 

NUM_APER=                    7 / Number of apertures.

SXAPER1 =                   2. / Aperture #1 in pixels

SXAPER2 =                   3. / Aperture #2 in pixels

SXAPER3 =                   5. / Aperture #3 in pixels

SXAPER4 =                   8. / Aperture #4 in pixels

SXAPER5 =                  12. / Aperture #5 in pixels

SXAPER6 =                  17. / Aperture #6 in pixels

SXAPER7 =                  23. / Aperture #7 in pixels

NUM_FOL =                    5 / Number of fraction-of-light radii.

SXFRAC1 =                  0.2 / Fraction-of-light radius #1

SXFRAC2 =                  0.5 / Fraction-of-light radius #2

SXFRAC3 =                  0.8 / Fraction-of-light radius #3

SXFRAC4 =                  0.9 / Fraction-of-light radius #4

SXFRAC5 =                 0.95 / Fraction-of-light radius #5

 

General information (may not be applicable)

 

ABSCAL  = '        '

CALINFO = '        '

STATFILE= '        '

ABSPIPE = '        '

PRUNDAT0= '        '

PRUNDAT1= '        '

NLEGS   =                 -999

MPSCOW  = '        '

PIPESTAT=                 -999

HISTORY NUV: HISTORY 14/11/04 21:48 Catalog created

 

Header card from NUV catalog file  Sextractor Output

 

NEPOCH  =                2000.

NOBJECT = 'CDFS_00_0037'

NORIGIN = 'SExtractor'

NCRVAL1 =            53.127785

NCRVAL2 =           -27.871367

NCRPIX1 =               1920.5

NCRPIX2 =               1920.5

NCDELT1 = -0.000416666666666667

NCDELT2 = 0.000416666666666667

NCROTA1 =                   0.

NCROTA2 =                   0.

 

Sextractor Parameters and Outputs (NUV)

 

NSXIMASX=                 3840 / IMAGE WIDTH (PIXELS) originally SEXIMASX

NSXIMASY=                 3840 / IMAGE HEIGHT (PIXELS)

NSXSTRSY=                 1024 / STRIP HEIGHT (LINES)

NSXIMABP=                  -32 / FITS IMAGE BITPIX

NSXPIXS =                  1.5 / PIXEL SCALE (ARCSEC)

NSXSFWHM=                  5.5 / SEEING FWHM (ARCSEC)

NSXNNWF = 'CDFS_00-nd-sexnnw.txt' / CLASSIFICATION NNW FILENAME

NSXGAIN =              44668.2 / GAIN (IN E- PER ADU)

NSXBKGND=                   0. / MEDIAN BACKGROUND (ADU)

NSXBKDEV=      0.0003236696066 / MEDIAN RMS (ADU)

NSXBKTHD=       4.47745806E-05 / EXTRACTION THRESHOLD (ADU)

NSXCONFF= 'CDFS_00-nd-sexparams.txt' / CONFIGURATION FILENAME

NSXDETT = 'CCD     '           / DETECTION TYPE

NSXTHLDT= 'SIGMA   '           / THRESHOLD TYPE

NSXTHLD =                   1. / THRESHOLD

NSXMINAR=                    8 / EXTRACTION MINIMUM AREA (PIXELS)

NSXCONV =                    T / CONVOLUTION FLAG

NSXCONVN=                    T / CONVOLUTION NORM. FLAG

NSXCONVF= 'CDFS_00-nd-gauss_30_7x7.txt' / CONVOLUTION FILENAME

NSXDBLDN=                   32 / NUMBER OF SUB-THRESHOLDS

NSXDBLDC=               0.0001 / CONTRAST PARAMETER

NSXCLN  =                    T / CLEANING FLAG

NSXCLNPA=                   1. / CLEANING PARAMETER

NSXCLNST=                   32 / CLEANING OBJECT-STACK

NSXAPERD=                    0 / APERTURE DIAMETER (PIXELS)

NSXAPEK1=                  2.5 / KRON PARAMETER

NSXAPEK2=                  2.5 / KRON ANALYSIS RADIUS

NSXAPEK3=                  3.5 / KRON MINIMUM RADIUS

NSXSATLV=           999999999. / SATURATION LEVEL (ADU)

NSXMGZPT=                   0. / MAGNITUDE ZERO-POINT

NSXMGGAM=                   4. / MAGNITUDE GAMMA

NSXBKGSX=                   64 / BACKGROUND MESH WIDTH (PIXELS)

NSXBKGSY=                   64 / BACKGROUND MESH HEIGHT (PIXELS)

NSXBKGFX=                    3 / BACKGROUND FILTER WIDTH

NSXBKGFY=                    3 / BACKGROUND FILTER HEIGHT

NSXPBKGT= 'GLOBAL  '           / PHOTOM BACKGROUND TYPE

NSXPBKGS=                   24 / LOCAL AREA THICKNESS (PIXELS)

NSXPIXSK=              1500000 / PIXEL STACKSIZE (PIXELS)

NSXFBUFS=                 1024 / FRAME-BUFFER SIZE (LINES)

NSXISAPR=                   0. / ISO-APER RATIO

NSXNDET =                34770 / NB OF DETECTIONS

NSXNFIN =                29869 / NB OF FINAL EXTRACTED OBJECTS

NSXNPARA=                   84 / NB OF PARAMETERS PER OBJECT

 

NUV Image and Exposure Data

 

NGRELEAS= 'ops-v4_0-RC2'

NCTYPE1 = 'RA---TAN'

NCTYPE2 = 'DEC--TAN'

NEQUINOX=                2000.

NRA_CENT=            53.127785

NDEC_CEN=           -27.871367 / originally DEC_CENT

NTWIST  =                   0.

NECLIPSE=                 -999

NGRSPA  =                -999.

NLEG    =                 -999

NMPSNPOS=                    0

NVISIT  =                   -1

NSUBVIS =                    0

NMINIVIS=                    0

NOW     =                    1

NBAND   =                    1

NROLL   =                -999.

NEXPTIME=              44668.2

NEXPSTAR=       1068392837.995 / originally EXPSTART

NEXPEND =       1070755524.985

NOBS-DAT= '2003-11-09'         / originally OBS-DATE

NTIME-OB= '15:47:18'           / orig:TIME-OBS, was OBS-TIME

NOBSSECS=                  -1.

NOBSDATI= 'unknown '           / originally OBSDATIM

NTILENAM= 'CDFS_00 '           / originally TILENAME

NTILENUM=                 6051

NPLANID =                   -1

NMPSPHAS= 'G1      '           / originally MPSPHASE

NMPSPLAN= 'deep    '

NMPSTYPE= 'DIS     '

NIMAGSZX=                 3840

NIMAGSZY=                 3840

NAVASPRA=     53.1298646069532

NAVASPDE=    -27.8761034951757

NAVASPRO=     203.961542187749

NAVASPOK=                -999.

NCALPATH= '        '

NFLATFL = '        '

NINTIMAG= '/home/runes5/fltops/pipe/01-vsn/06051-CDFS_00/d/01-main/0001-img/04&'

CONTINUE  '-try/CDFS_00-nd-int.fits' / originally INTIMAGE

NPHOFILE= '        '

NNVALIDP=                   -1 / originally NVALIDPH

NFILTERE=                    1 / originally FILTERED

NPSFFWHM=                  4.5

NTEDMODE=                    1

NSIGTHRE=                 -999

NABSTHRE=                    2

NABSCAL = '        '

NCALINFO= '        '

NSTATFIL= '        '

NABSPIPE= '        '

NPRUNDA0= '        '

NPRUNDA1= '        '

NNLEGS  =                 -999

NMPSCOW = '        '

NPIPESTA=                 -999

HISTORY FUV: HISTORY 14/11/04 22:00 Catalog created

 

Header cards from FUV catalog file  Sextractor Output

 

FEPOCH  =                2000.

FOBJECT = 'CDFS_00_0037'

FORIGIN = 'SExtractor'

FCRVAL1 =            53.127785

FCRVAL2 =           -27.871367

FCRPIX1 =               1920.5

FCRPIX2 =               1920.5

FCDELT1 = -0.000416666666666667

FCDELT2 = 0.000416666666666667

FCROTA1 =                   0.

FCROTA2 =                   0.

 

Sextractor Parameters and Outputs (FUV)

 

FSXIMASX=                 3840 / IMAGE WIDTH (PIXELS) originally SEXIMASX

FSXIMASY=                 3840 / IMAGE HEIGHT (PIXELS)

FSXSTRSY=                 1024 / STRIP HEIGHT (LINES)

FSXIMABP=                  -32 / FITS IMAGE BITPIX

FSXPIXS =                  1.5 / PIXEL SCALE (ARCSEC)

FSXSFWHM=                   5. / SEEING FWHM (ARCSEC)

FSXNNWF = 'CDFS_00-fd-sexnnw.txt' / CLASSIFICATION NNW FILENAME

FSXGAIN =             44667.95 / GAIN (IN E- PER ADU)

FSXBKGND=                   0. / MEDIAN BACKGROUND (ADU)

FSXBKDEV=      7.131370512E-05 / MEDIAN RMS (ADU)

FSXBKTHD=      4.477483162E-05 / EXTRACTION THRESHOLD (ADU)

FSXCONFF= 'CDFS_00-fd-sexparams.txt' / CONFIGURATION FILENAME

FSXDETT = 'CCD     '           / DETECTION TYPE

FSXTHLDT= 'SIGMA   '           / THRESHOLD TYPE

FSXTHLD =                   1. / THRESHOLD

FSXMINAR=                    8 / EXTRACTION MINIMUM AREA (PIXELS)

FSXCONV =                    T / CONVOLUTION FLAG

FSXCONVN=                    T / CONVOLUTION NORM. FLAG

FSXCONVF= 'CDFS_00-fd-gauss_30_7x7.txt' / CONVOLUTION FILENAME

FSXDBLDN=                   32 / NUMBER OF SUB-THRESHOLDS

FSXDBLDC=               0.0001 / CONTRAST PARAMETER

FSXCLN  =                    T / CLEANING FLAG

FSXCLNPA=                   1. / CLEANING PARAMETER

FSXCLNST=                   32 / CLEANING OBJECT-STACK

FSXAPERD=                    0 / APERTURE DIAMETER (PIXELS)

FSXAPEK1=                  2.5 / KRON PARAMETER

FSXAPEK2=                  2.5 / KRON ANALYSIS RADIUS

FSXAPEK3=                  3.5 / KRON MINIMUM RADIUS

FSXSATLV=           999999999. / SATURATION LEVEL (ADU)

FSXMGZPT=                   0. / MAGNITUDE ZERO-POINT

FSXMGGAM=                   4. / MAGNITUDE GAMMA

FSXBKGSX=                   64 / BACKGROUND MESH WIDTH (PIXELS)

FSXBKGSY=                   64 / BACKGROUND MESH HEIGHT (PIXELS)

FSXBKGFX=                    3 / BACKGROUND FILTER WIDTH

FSXBKGFY=                    3 / BACKGROUND FILTER HEIGHT

FSXPBKGT= 'GLOBAL  '           / PHOTOM BACKGROUND TYPE

FSXPBKGS=                   24 / LOCAL AREA THICKNESS (PIXELS)

FSXPIXSK=              1500000 / PIXEL STACKSIZE (PIXELS)

FSXFBUFS=                 1024 / FRAME-BUFFER SIZE (LINES)

FSXISAPR=                   0. / ISO-APER RATIO

FSXNDET =                19913 / NB OF DETECTIONS

FSXNFIN =                16377 / NB OF FINAL EXTRACTED OBJECTS

FSXNPARA=                   84 / NB OF PARAMETERS PER OBJECT

FGRELEAS= 'ops-v4_0-RC2'

 

FUV Image and Exposure Data

 

FCTYPE1 = 'RA---TAN'

FCTYPE2 = 'DEC--TAN'

FEQUINOX=                2000.

FRA_CENT=            53.127785

FDEC_CEN=           -27.871367 / originally DEC_CENT

FTWIST  =                   0.

FECLIPSE=                 -999

FGRSPA  =                -999.

FLEG    =                 -999

FMPSNPOS=                    0

FVISIT  =                   -1

FSUBVIS =                    0

FMINIVIS=                    0

FOW     =                    1

FBAND   =                    2

FROLL   =                -999.

FEXPTIME=             44667.95

FEXPSTAR=       1068392837.995 / originally EXPSTART

FEXPEND =       1070755524.985

FOBS-DAT= '2003-11-09'         / originally OBS-DATE

FTIME-OB= '15:47:18'           / orig:TIME-OBS, was OBS-TIME

FOBSSECS=                  -1.

FOBSDATI= 'unknown '           / originally OBSDATIM

FTILENAM= 'CDFS_00 '           / originally TILENAME

FTILENUM=                 6051

FPLANID =                   -1

FMPSPHAS= 'G1      '           / originally MPSPHASE

FMPSPLAN= 'deep    '

FMPSTYPE= 'DIS     '

FIMAGSZX=                 3840

FIMAGSZY=                 3840

FAVASPRA=     53.1298645875342

FAVASPDE=    -27.8761079159628

FAVASPRO=     203.961523402068

FAVASPOK=                -999.

FCALPATH= '        '

FFLATFL = '        '

FINTIMAG= '/home/runes5/fltops/pipe/01-vsn/06051-CDFS_00/d/01-main/0001-img/04&'

CONTINUE  '-try/CDFS_00-fd-int.fits' / originally INTIMAGE

FPHOFILE= '        '

FNVALIDP=                   -1 / originally NVALIDPH

FFILTERE=                    1 / originally FILTERED

FPSFFWHM=                  4.5

FTEDMODE=                    1

FSIGTHRE=                 -999

FABSTHRE=                    2

FABSCAL = '        '

FCALINFO= '        '

FSTATFIL= '        '

FABSPIPE= '        '

FPRUNDA0= '        '

FPRUNDA1= '        '

FNLEGS  =                 -999

FMPSCOW = '        '

FPIPESTA=                 -999

DATE    = '2004-11-15T06:08:10' / file creation date (YYYY-MM-DDThh:mm:ss UT)

END                                                              

 

 

 

6.    Pipeline Products Gallery

 

The images below show ds9 snapshots of some of the main pipeline image products.  FUV images are on the left, NUV on the right.  Specific details can be seen in the magnifier image (upper right), which is providing a zoom around the cursor position (indicated by the white arrow in the image).  (Note that the figures are described in the text  precedes the image.)

These images have been obtained from the pipeline a single visit to the target M51 (NGA_M51_0001)

Dose Map

The dose map contains photon positions in the instrument frame.  The full field of view is 65 mm diameter, or 1.24 degrees in the telescope focal plane.  Note that the NUV image frame is rotated 180 degrees from the FUV frame. 

Because of the dither motion by the satellite, stars and galaxies move in this frame during an observation (appearing in this image as donuts or smeared objects).  Point sources in these images are “detector hot spots” which are masked in further processing.

The four points at the corners of the images are generated by electronic stimulus pulses in the detector system.  These are used for calibration of electronic drift and dead time corrections only and do not show up in the final images.

 

 

Count Map

The combination of time-tagged photon positions and satellite aspect satellite are used to generate a count map in sky coordinates.  This observation was acquired at a roll angle of 90 degrees (measured with respect to the Y axis of the detector/instrument frame), which explains why the image is rotated with respect to the dose maps above.

The image quantities are in units of counts per pixel.  Each pixel is 1.5”x1.5”.  Note that at the position of the arrow, 50 counts were detected in this exposure.

Relative Response Map

The high resolution relative response map shows the effective normalized instrument response (based on flat field) * exposure (seconds) projected onto the sky.   The small annuli are in regions of the detector active area (hot spots) which have been masked in pipeline processing. The annular shape results from the removal of the dither pattern used in pointing during observations.

Over most of the active area, the response varies by less than +/- 20%.  The FUV detector shows much larger response variation across the field, particularly on one side where the response drops off significantly. 

 

Intensity map

The intensity map is generated by dividing the count map by the relative response map.  The units are in counts / pixel s (normalized effective area*bandwidth), which means that while the image is ‘flattened’ to reflect the true instrument response, the units correspond roughly to counts per second per pixel.  At the position of the arrow (highlighted in the magnifier), we detected ~ 0.082 counts/(s normalized EA pixel) in the NUV image.  This can easily be converted to a surface brightness using the conversion factors provided in the table above. 

Note that in the low response region of the FUV detector, the average level is relatively flat, but the image becomes noisy as expected due to the low throughput in this region.

 

Sky Background Map

            The GALEX pipeline generates a smoothed sky background map which is subtracted from the intensity image prior to the final source extraction processing step. See: Background_determination_and_source_extraction_for_GALEX_data.pdf

 

 

Grism Intensity Maps

 

Intensity maps are also built up in grism mode.  The quad image below shows imaging and grism intensity maps of the ELAISS1_00 field.  The grism data are from a single visit (and grism rotation).

 

 

7.    GALEX Image Artifacts

 

The GALEX optics and detector produce several image artifacts which the pipeline flags to indicate regions where analysis problems may arise.  Most image artifacts are observed in the NUV channel due to a bevel on the edge of the NUV window and the abundance of bright stars detected vs. the FUV.  The principal artifacts are:

Other artifacts are produced by transient effects.  These include

 

The pipeline flags possible artifacts for the NUV detector and masks known detector hot spots.

 

Table 3.3 -- Artifact Gallery

Artifact

Pipeline Flag

Picture [NUV=red/yellow, FUV=blue]

Bright star halo [NUV]

 

Due to diffraction, and electron halo due to proximity focused photocathode.

NONE

Bright star halo [FUV]

NONE

Ghosts—Window & Dichroic

 

The small ghost to the upper right is due to the dichroic beam splitter. It is offset along the detector Y-axis (instrument X-axis) and oblique due to the oblique angle of the beam splitter.

 

The largest (dim red, lower) ghost is due to the 10 mm thick NUV detector window. Detector window ghosts are radially offset due to curvature on the window.

 

FUV hot spot

 

Normally masked out in pipeline, new hotspots not in database will appear as spiral dither pattern (since hot spots are fixed in detector coordinates and the aspect is corrected to account for the dithered pointing during observations).

 

NUV Window Bevel Reflection – Edge Ghost

 

The NUV window has a beveled interior surface required to locate the photocathode surface close to the microchannel plate surface. Total internal reflection causes light from stars within 5 arcminutes of the edge to reflect into the field of view. Depending on the exact location of the star, a ghost image can be produced far inside the field of view, as shown in the next image

 

NUV Window Bevel Reflection – Interior Ghost