Quality Control and
Data Processing

The names of all calibration pipeline products follow a certain naming convention. This is done to have human-readable rather than technical file names. The naming scheme has been chosen to have the type of product, its date of creation, and its pipeline-relevant setup values recognizable in the product name.

The general format of user-oriented product file names is the same for all VLT/VLTI instruments.

On the archive interface, the master calibrations can be associated to science files and downloaded. Then they carry technical filenames (the archive filename ARCFILE). In order to rename them to the original filenames, search for the fits header key ORIGFILE. The naming scheme of ORIGFILE is described here.

Instrument code

All product names start with two letters which are specific for the instrument. For instance: UVES product names start with 'UV', VISIR names with 'VR'.

Product category

The full value of the product category is coded in the FITS header key HIERARCH.ESO.PRO.CATG. A short form of this tag is encoded in four characters being unique per instrument:

1st letter	M or P	calibration product
	G	general (static) calibration product
2nd to 4th letter	...	type of product

Calibration products come in two flavours: dynamic ones (being updated regularly, short validity), and static ones (never or rarely updated). The static ones are also called 'general' because they often are not derived from raw data (like e.g. a line catalogue).

Both product types are stored in the archive and are available for download through the calSelector service.

All OmegaCAM pipeline product names begin with "OC_".

OC_S . . . are science products.

OC_P and OC_M . . . are calibration products.

OmegaCAM SCIENCE PIPELINE PRODUCTS

In view of the current Quality Control scheme, science processing is not done. However, in the some special cases (i.e. during the first 6 months of operations) it can be done. Thus, for completeness the OmegaCAM pipeline products are listed. They have the following naming scheme:

OC_[SXXX]_[OBS_ID]_[date_time]_[BINNING_X]_[BINNING_Y]_[READ_MODE]_[READ_SPEED]_[FILTER_NAME].[ext]

where:

• [SXXX] is the four letter code uniquely describing the type of product (the first letter is always S for SCIENCE). All these codes are listed below.
• [OBS_ID] is the Observing Block (OB) number of the observation read from the OBS.ID fits header
• [date_time] is the UT date and time of the first raw frame measured for the OB (e.g. 2009-01-01T04:31:12); this information is required since OBs can be executed several times
• [BINNING_X] is a string containing the instrumental binning size as read from the DET.WIN1.BINX fits header (generally, 1)
• [BINNING_Y] is a string containing the instrumental binning size as read from the DET.WIN1.BINY fits header (generally, 1)
• [READ_MODE] is a string containing the instrumental read-out mode as read from the DET.READ.MODE fits header (generally, normal)
• [READ_SPEED] is a string containing the instrumental read-out speed as read from the DET.READ.SPEED fits header (generally, normal)
• a small subset of science products (OC_SSDI or OC_SSMA) are given an additional 4 digit number (i.e. 0004, 0041, 0042, etc.) . This is needed because these frames are products based on SINGLE exposures (and not the coaddition of all the exposures contained in the OB), and hence all have identical filter names, binning, and read modes.
• [FILTER_NAME] is a string containing the filter name as read from the INS.FILT1.NAME fits header.
• [ext] is fits or hdr

e.g.

OC_SSCI_705898_2012-05-29T06:48:12_1_1_normal_normal_r_SDSS.fits

OC_SSDI_715898_2012-07-08T06:48:12_g_SDSS_1_1_normal_normal_g_SDSS.fits

SCIENCE PIPELINE PRODUCTS

The following OmegaCAM science products presently exist:

Code	type of file	PRO_CATG
SSCI	full, coadded stack of science frames (coaddition of all exposures in one OB)	STACK_SCIENCE
SCMS	science confidence map associated with science frames (coaddition of all images in one OB)	CONF_MAP_SCIENCE
SCAT	catalogue of all detected sources in science frame stack (fits table)	SCIENCE_CATALOGUE
SSDI	fully processed, single pointing science frame within the dither template	SIMPLE_DITHER
SSJI	fully processed, single pointing science frame within the jitter template	SIMPLE_JITTER
SOFF	fully processed, single pointing science frame within the offset template	SIMPLE_OFFSET
SSTA	fully processed, single pointing science frame within the stare template	SIMPLE_STARE
SSMA	the bad pixel mask associated with the fully processed, single pointing science frame	SIMPLE_MASK

CALIBRATION PIPELINE PRODUCTS

OmegaCAM calibration products come in two flavours: dynamic ones (being updated regularly and having a relatively short validity), and static ones (never, or rarely updated). Both products are stored in the archive. The static ones (also called general calibration products) are also delivered in the public pipeline releases.

Dynamic calibrations. The following types of dynamic calibration products of OmegaCAM presently exist:

Code	type of file	PRO_CATG
MBIA	master bias	MASTER_BIAS
MHPM	bad pixel map (hot pixels only)	HOT_PIXELS_MAP
PRNA*	bias read-out noise (fits table)	READNOISE_ADU
MDAR	master dark frame	MEAN_DARK
PLIF*	single dome flat instrument life test	LIFETEST_CHECK
PSHU*	shutter timing test (shutter direction of travel: up)	DOME_SHUTTERTEST
PSHD*	shutter timing test (shutter direction of travel: down)	DOME_SHUTTERTEST
PDLI	detector linearity information (fits table)	DET_LIN_INFO
PDGI	detector gain information (fits table)	GAIN_INFO
PDCC*	product cube of the detmon linearity coefficients cube	COEFFS_CUBE
PDC0*	single plane of detmon linearity coefficients cube (coeff 0)	COEFFS_CUBE_P0
PDC1*	single plane of detmon linearity coefficients cube (coeff 1)	COEFFS_CUBE_P1
PDC2*	single plane of detmon linearity coefficients cube (coeff 2)	COEFFS_CUBE_P2
PDC3*	single plane of detmon linearity coefficients cube (coeff 3)	COEFFS_CUBE_P3
PDC4*	single plane of detmon linearity coefficients cube (coeff 2)	COEFFS_CUBE_P4
PDNL*	map of non-linear pixels	DB_MAP_NL
PDDF*	difference images between the dome flats of the detmon template	DIFF_FLAT
PDAC*	auto-correlation of the images of the detmon template	AUTOCORR
PILL	illumination correction frame	ILLUMINATION
MFLD	master dome flat	MASTER_FLAT_DOME
MCPM	cold pixel map based on dome flat template	COLD_PIXELS_MAP
MFLA	master flat based on the combination of the master dome flat and the master twilight flat	MASTER_FLAT
MFLT	master twilight flat	MASTER_FLAT_TWILIGHT
MBPM	master bad pixel map based on the combination of the hot and cold pixel maps	BAD_PIXELS_MAP
PSTD	fully reduced standard star image	REDUCED_STD
PSMA	the bad pixel mask of the reduced standard star image	REDUCED_STD_MASK
PPHO	photometric table based on detected and extracted stars in reduced standard star field	PHOTOMETRIC_TABLE
PZPT	standard star zeropoints table	ZEROPOINTS

* A quality control product only: These products are not ingested into the archive data base.

Static calibrations.

Static calibration products are also named according to a "nearly" standard OmegaCAM naming scheme.

Code	type of file	PRO_CATG	Example
GEXT	extinction curve fits table	EXTINCTION_CURVE	OC_GEXT_110729_ALL.fits
GUSN	master catalogue of USNO A2 stars	MASTER_USNOA2_CATALOGUE	OC_GUSN_110728_USNOA2.fits
GSTD	master catalogue of secondary standard stars (equatorial and polar fields)	REFERENCE_STAR_CATALOG	OC_GSTD_110728_ALL.fits
GMON	monitoring report	MONITOR_REPORT	OC_GMON_110728_ALL.fits

Date of origin, version

The date of origin is identical to the date of the raw data measurement. It is coded as, e.g., 120331 for March 31, 2012.

The version of a file is indicated by capital letters always starting with A. Versioning is supported for certain types of files, see the above table. In all other cases, only one version per day is created (always A).

Instrumental parameters

The instrument parameters characterizing a setup are included in the product name. Most products have the following scheme:

OC_[MCODE][DATE][BINNING_X][BINNING_Y][READ_MODE][READ_SPEED][FILTER_NAME]

where:

• BINNING_X/Y is usually: 1 / 1
• READ_MODE is usually: normal
• READ_SPEED is usually: normal
• FILTER_NAME can be: u_SDSS / g_SDSS / r_SDSS / i_SDSS / z_SDSS / B_JOHN / V_JOHN / v_STRM / H_ALPHA / NB_659 / NB_852 / u_g_r_i_SDSS / opaque

for example:

OC_MFLA_120708_normal_normal_1_1_r_SDSS.fits

The [BINNING_X], [BINNING_Y], [READ_MODE] and [READ_SPEED] have been unchanged since the beginning of operations, Thus, they are currently skipped in the naming scheme, i.e.

OC_MFLA_120708A_r_SDSS.fits

Suffix

All product files have extension .fits. They have either image format or binary table format.