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AAO OBSERVER System FITS header items, 25-Jan-2001

The AAO OBSERVER data adds various items to the header of the data files it creates, known as "FITS Keyword Items". (This name arises because when the files are converted to FITS tapes, the items become part of the FITS header".

The actual items added depend on the mode in which Observing is done. For example, some items are relevant for the IRIS infrared system which are not relevant for normal CCD observations. The system will only add the IRIS specific items when IRIS is being run.

This document describes all the header items added by the AAO Observer CCD system. The first table describes the items which are part of the standard CCD system whilst later tables define instrument specific items.

For each of these there is a table with the following columns
Name
The name of the FITS item
Present
Indicates if the item is ALWAYS present or is OPTIONAL
Type
Indicates the FITS type of the item, one of CHAR, INT, REAL, LOGICAL or (CHAR ARRAY)
Value
Indicates if the value if FIXED or VARIABLE. Fixed means that the value will be fixed from INITIALISE/RESET of the system until it is RESET/EXITed. Thus all files produced during this interval will have the same value. Variable values may change from one run to the next.
Indicates the possible values, if appropiate
Details
Comments about the item in question.

History

23-Aug-2000

Added History section. Added TELFOCUS item, currently only available on WFI but will be added later to other instruments (and may be added by the Night Assistant Software to all instruments).

Standard Items

These items are part of the Standard AAO CCD system. Note that since the IRIS infrared system uses the same underlying CCD hardware and software, IRIS may be mentioned in some of these items.

We break these into three sets to avoid confusion. There is a set for the Telescope Details, such as where the telescope was pointing, what the focus was etc. There is a set for the Detector Details, such as read out speed, read out window, read out noise etc. And there is a general section describing all the other keywords.

General items

Name Present Type Value Details
TELESCOP ALWAYS CHAR FIXED Telescope name
OBSERVER ALWAYS CHAR FIXED Names of Observers
INSTRUME ALWAYS CHAR FIXED Instrument name
ORIGIN ALWAYS CHAR FIXED Originating Institution (AAO)
ALT_OBS ALWAYS INT FIXED Altitude of observatory, meters
LAT_OBS ALWAYS INT FIXED Latitude of observatory, degrees
LONG_OBS ALWAYS INT FIXED Longitude, degrees
UTDATE ALWAYS CHAR VARIABLE Date of observation, YYYY:MM:DD
RUN ALWAYS CHAR VARIABLE Run number (Integer or A-Z for Dummy)
GCT_DATE ALWAYS CHAR FIXED Control task version date
GCT_VER ALWAYS CHAR FIXED Control task version number
COMMENT ALWAYS (CHAR ARRAY) VARIABLE User supplied command, use the COMMENT command
RUNCMD ALWAYS CHAR VARIABLE Command used to take run. One of RUN, DARK, FLAT, SKY, BIAS, DUMMY, KEEP, RECOVER, ARC, DFLAT, SFLAT.
OBJECT ALWAYS CHAR VARIABLE Object being observer as input using OBJECT command. Defaults based on run name
TEL_VER ALWAYS CHAR FIXED Tel task version number
TEL_DATE ALWAYS CHAR FIXED Tel task version date
CCD_VER ALWAYS CHAR FIXED CCD Task version number
CCD_DATE ALWAYS CHAR FIXED CCD Task version date
UTSTART ALWAYS CHAR VARIABLE HH:MM:SS.DD     The UT Time at the start of the exposure. This is determinied by calibrating the VAX system clock against the Observatory's CAMAC based clock. This calibration is done at system initialisation/reset (and in the future, after Jan 1999, on readout method changes). The calibration relies on the CAMAC clock being correct and the VAX system clock not losing or gaining significant time (more then 10ms) during a night. It does NOT rely on the VAX time being correct.

This value should be accurate to 20ms, but there is some uncertainity which occurs due to the potential time delays between reading the this time and sending the actual start command to the CCD micro (Time for RS232 communications and the potential process context switch which may occur when doing I/O). This uncertainity is determined by the software and is given by the DTSTART parameter, such that the actual start time of the observation is between UTSTART and UTSTART+DTSTART plus/minus 20ms.

The low level CCD Microprocessor should be accurate to one part in 100000 of the exposure time.
UTEND ALWAYS CHAR VARIABLE HH:MM:SS.DD     Time at end of exposure
STSTART ALWAYS CHAR VARIABLE HH:MM:SS Sidereal Time at start of exposure
STEND ALWAYS CHAR VARIABLE HH:MM:SS Sidereal at end of expsoure
DTSTART ALWAYS REAL VARIABLE The Uncertainty in the UTSTART value. (seconds) 20ms accuracy. This value gives the uncertainty in time the exposure started, due to factors such as I/O timing and process context switching. Whilst it may not always have the correct number of significant digits displayed, it is accurate to 20ms. (Added in 1996). See UTSTART for more details

Telescope Details

Here we have the details of the items relating to the Telescope, such as where it was pointing, what the focus was etc.

Name Present Type Value Details
HASTART ALWAYS FLOAT VARIABLE HA at start of observation (degrees)
HAEND ALWAYS FLOAT VARIABLE HA at end of observation (degrees)
ZDSTART ALWAYS FLOAT VARIABLE ZD at start of observation (degress)
ZDEND ALWAYS FLOAT VARIABLE ZD at end of observatory (degress)
TOPEND ALWAYS CHAR FIXED Telescope Top End. Only from TEL version 4.0 onwards.
TEL_PA OPTIONAL FLOAT FIXED Telescope A&G position angle, degrees. Only available when the using cassigran instruments. Only from TEL version 4.0 onwards.
TELFOCUS TBD FLOAT VARIABLE Telescope Focus position, mm. Currenlty (23-Aug-2000) only avaialable on WFI but may be added to other instruments later.
TRACKING ALWAYS CHAR VARIABLE Indicates telescope mode, one of TRACKING/STOPPED/SLEWING/PARKED
MEANRA OPTIONAL FLOAT VARIABLE Current mean place position right ascension
MEANDEC OPTIONAL FLOAT VARIABLE Current mean place postion declination
EQUINOX OPTIONAL FLOAT VARIABLE Equinox of mean place (YEARS A.D.)
BASE_RA OPTIONAL FLOAT VARIABLE Base mean place position right ascension
BASE_DEC OPTIONAL FLOAT VARIABLE Base mean place position declination
BEQUINOX OPTIONAL FLOAT VARIABLE Base position equinox
APPRA OPTIONAL FLOAT VARIABLE Current apparent place position right ascension
APPDEC OPTIONAL FLOAT VARIABLE Current apparent place position declination
OFFRA OPTIONAL FLOAT VARIABLE Offset from current base position in R.A.
OFFDEC OPTIONAL FLOAT VARIABLE Offset from current base position in declinaton
COSDEC OPTIONAL FLOAT VARIABLE If true R.A. offset is "on sky" - offset is divided by COS(DEC) for use on hour angle
EPOCH ALWAYS FLOAT VARIABLE Reference date for coordinates (YEARS A.D.)
AXIS ALWAYS CHAR VARIABLE Selected axis. One of A/B/Ref

Note, added during 96

Note, faulty prior to Sep 97, always had value at system init time
AXISLOCK ALWAYS LOGICAL VARIABLE Are buttons enabled

Note, added during 96

Note, faulty prior to Sep 97, Always had value at system init time
AXIS_X ALWAYS INT VARIABLE Optical axis x in mm

Note, added during 96

Note, faulty prior to Sep 97, Always had value at system init time
AXIS_Y ALWAYS INT VARIABLE Optical axis y in mm

Note, added during 96

Note, faulty prior to Sep 97, always had value at system init time

Detector Details

Here we have the details of the Detector, such as the read out speed and window, exposure times etc.

Our CCD systems can have 2 Windows. If only one window is being used, the keywords WINDOXS, WINDOXE, WINDOYS, and WINDOYE will be defined. If two windows are being used the keywords WINDOXS1, WINDOXE1, WINDOYS1, WINDOYE1, WINDOXS2, WINDOXE2, WINDOYS2, and WINDOYE2

The PRESCAN item (number of prescan columns) is only output if there are prescan columns. These columns are always the left most columns of the first window and the left most columns of the data frame. (Note, binning can affect the later).

The OFFCHIPX item (number of overscan columns) is only output if there are overscan columns. These columns are the right most columns second window if there are two windows or the right most columns of the window if there is only one. Again, they are the right most columns of the data frame and may be affected by binning.

The CCD device can have up to 6 X direction and 3 Y direction binning fields. There is always at least one field in each direction. Keywords for the other fields are only output if they are defined.

The bin factors (FIELDXB1, FIELDYB1 etc.) are not output unless binning is greater then one.

Name Present Type Value Details
WINDOW ALWAYS CHAR VARIABLE CCD readout window name
SPEED ALWAYS CHAR VARIABLE CCD readout speed name
METHOD ALWAYS CHAR VARIABLE CCD Readout method. One of - (command in brackets)
  • Normal ccd control method (method ccd_normal)
  • Time series control method (method series)
  • Multiple ccd exposures (method multiple)
  • IRIS double correlated readouts (method 1)
  • IRIS double double correlated readouts (method 2 and method 2A)
  • IRIS double double correlated readouts with NDR allows (method 2B)
  • IRIS double double correlated readouts with reg NDR's (method 2C)
  • IRIS Multiple sample readouts (method 4)
  • CCD Charge shuffling technique (method shuffle)
DETECTOR ALWAYS CHAR FIXED CCD Chip name
EXPOSED ALWAYS REAL VARIABLE Integration time (seconds) for a single cycle. Note that normal CCD runs have only one cycle. Where the detector has a shutter and the shutter is opened, this value indicates the time the shutter was open for each cycle. (This is taken from the time the shutter begins to open to the time it begins to close)
ELAPSED ALWAYS REAL VARIABLE Elapsed time (seconds). This indicates the total time which elapsed from the end of the erase sequence (which occurs at the beginning of the exposure) to the beginning of the readout.
FLASH ALWAYS REAL VARIABLE Pre-exposure flash time (seconds) (in current system, ALWAYS 0)
TOTALEXP ALWAYS REAL VARIABLE Sum of Exposed times for the observation. A run may be made up of multiple exposures (i.e. Time series, charge shuffling and IRIS modes with multiple cycles) this value indicates the total exposure time.
DETECXS ALWAYS INT FIXED First column of detector
DETECXE ALWAYS INT FIXED Last column of detector
DETECYS ALWAYS INT FIXED First row of detector
DETECYE ALWAYS INT FIXED Last row of detector
WINDOXS OPTIONAL INT VARIABLE First CCD column of single window
WINDOXE OPTIONAL INT VARIABLE Last CCD column of single window
WINDOYS OPTIONAL INT VARIABLE First CCD row of single window
WINDOYE OPTIONAL INT VARIABLE Last CCD row of single window
WINDOXS1 OPTIONAL INT VARIABLE First CCD column of first window
WINDOXE1 OPTIONAL INT VARIABLE Last CCD column of first window
WINDOYS1 OPTIONAL INT VARIABLE First CCD row of first window
WINDOYE1 OPTIONAL INT VARIABLE Last CCD row of first window
WINDOXS2 OPTIONAL INT VARIABLE First CCD column of second window
WINDOXE2 OPTIONAL INT VARIABLE Last CCD column of second window
WINDOYS2 OPTIONAL INT VARIABLE First CCD row of second window
WINDOYE2 OPTIONAL INT VARIABLE Last CCD row of second window
FIELDXS1 OPTIONAL INT VARIABLE First CCD column of first x-binning field
FIELDXE1 OPTIONAL INT VARIABLE Last CCD column in first x-binning field
FIELDXB1 OPTIONAL INT VARIABLE CCD columns/bin in first x-binning field
FIELDXS2 OPTIONAL INT VARIABLE First CCD column of second x-binning field
FIELDXE2 OPTIONAL INT VARIABLE Last CCD column of second x-binning field
FIELDXB2 OPTIONAL INT VARIABLE CCD columns/bin in second x-binning field
FIELDXS3 OPTIONAL INT VARIABLE First CCD column of third x-binning field
FIELDXE3 OPTIONAL INT VARIABLE Last CCD column of third x-binning field
FIELDXB3 OPTIONAL INT VARIABLE CCD columns/bin in third x-binning field
FIELDXS4 OPTIONAL INT VARIABLE First CCD column of fourth x-binning field
FIELDXE4 OPTIONAL INT VARIABLE Last CCD column of fourth x-binning field
FIELDXB4 OPTIONAL INT VARIABLE CCD columns/bin in fourth x-binning field
FIELDXS5 OPTIONAL INT VARIABLE First CCD column of fifth x-binning field
FIELDXE5 OPTIONAL INT VARIABLE Last CCD column of fifth x-binning field
FIELDXB5 OPTIONAL INT VARIABLE CCD columns/bin in fifth x-binning field
FIELDXS6 OPTIONAL INT VARIABLE First CCD column of sixth x-binning field
FIELDXE6 OPTIONAL INT VARIABLE Last CCD column of sixth x-binning field
FIELDXB6 OPTIONAL INT VARIABLE CCD columns/bin in sixth x-binning field
FIELDYS1 OPTIONAL INT VARIABLE First CCD row in first y-binning field
FIELDYE1 OPTIONAL INT VARIABLE Last CCD row in first y-binning field
FIELDYB1 OPTIONAL INT VARIABLE CCD rows/bin in first y-binning field
FIELDYS2 OPTIONAL INT VARIABLE First CCD row in second y-binning field
FIELDYE2 OPTIONAL INT VARIABLE Last CCD row in second y-binning field
FIELDYB2 OPTIONAL INT VARIABLE CCD rows/bin in second y-binning field
FIELDYS3 OPTIONAL INT VARIABLE First CCD row in third y-binning field
FIELDYE3 OPTIONAL INT VARIABLE Last CCD row in third y-binning field
FIELDYB3 OPTIONAL INT VARIABLE CCD rows/bin in third y-binning field
PRESCAN OPTIONAL INT VARIABLE Virtual CCD columns digitised before the CCD chip
OFFCHIPX OPTIONAL INT VARIABLE Virtual CCD columns digitised after the CCD chip
CYCLES OPTIONAL INT VARIABLE Number of expose-readout sequences when there are multiple exposures making up one run. Valid for IRIS, Time Series and Charge Shuffling modes
PERIOD OPTIONAL REAL VARIABLE Period in time series and iris modes

For CCD Time Series, this is the time between the start of one exposure and the start of the next. Note that one run results in one image file.

For IRIS method 4, the period is the time between non-descructive readouts within each exposure. It must be appropriate for the integration time.
SHUTMODE OPTIONAL CHAR VARIABLE Shutter mode. Values: CLOSED, OPEN, EXPOSE. Used in Time Series mode only. OPEN the shutter is open for the entire run whilst EXPOSE indicates the shutter is open and closed for each Time Series exposure
RO_GAIN OPTIONAL REAL VARIABLE Readout amplifier (inverse) gain (e-/ADU)
RO_NOISE OPTIONAL REAL VARIABLE Readout noise (electrons)

RGO Spectrograph specific items

For these items to be in the data files, the RGO task must have been started as part of the Observer system

The RGO s/g has 2 filter wheels in front of the star beam, another 2 in front of the comparison source, a below slit filter slide in front of both sources, and a separate fibre filter wheel.

Name Present Type Value Details
GRATID ALWAYS CHAR VARIABLE Grating id. Not being set as. yet (lack of hardware support) Will have values like `1200B', `300B', `270R'etc.
GRATANGL ALWAYS REAL VARIABLE Grating angle. For RGO ~-10 to +100
GRATBLAZ ALWAYS CHAR VARIABLE Grating blaze direction. Either COLLIMATOR or CAMERA.
SLITWIDE ALWAYS REAL VARIABLE Slit width (mm). Range 0.010 to 2mm.
DEKKER ALWAYS REAL VARIABLE Dekker identifer. A number, range 0 to 99, but actually only 2 dozen or so fixed values should appear, but the encoded value is displayed rather than the 'name' of the dekker.
COLIMPOS ALWAYS REAL VARIABLE Collimator focus (mm). Range ~0 to 10mm
SOURCE ALWAYS CHAR VARIABLE Light path One of `STAR', `Cu-Ar comparison', `Tungsten lamp', `FIBRE FEED', `COMPARISON (no lamp)', `Cu-Ar + Tungsten'
SFILT1 ALWAYS CHAR VARIABLE Star filter 1
SFILT2 ALWAYS CHAR VARIABLE Star filter 2
LFILT1 ALWAYS CHAR VARIABLE Comparison lamp filter 1
LFILT2 ALWAYS CHAR VARIABLE Comparsion lamp filter 2
BSFILT ALWAYS CHAR VARIABLE Below slit filter
CALCITE ALWAYS CHAR VARIABLE Calcite in beam, one of , IN or OUT
FIBFILT ALWAYS CHAR VARIABLE Fibre input filter.

IRIS specific items

These items are added when running IRIS and represent the CAMERA details. Detector details are part of the general CCD details supplied in the general case above.

Name Present Type Value Details
IRIS_UFT ALWAYS CHAR VARIABLE Iris upper filter wheel position One of OPEN, RG630, HMA, HMB, HK
IRIS_LFT ALWAYS CHAR VARIABLE Iris lower filter wheel position. One of OPEN, K, 1.74, 2.34, 2.21, 2.16, 2.12, WIDEK, J , H
IRIS_LEN ALWAYS CHAR VARIABLE Field change lens position. One of WIDE, NARROW, INTERM, MIRROR
IRIS_GRM ALWAYS CHAR VARIABLE Echelle/grism wheel position. One of IJ,ND,OPEN,HMA,HMB
IRIS_SLT ALWAYS CHAR VARIABLE Slit name. One of OPEN, GRID, NARROW, WIDE, VNARROW, LNARROW, LWIDE, HOLE, LHOLE
IRIS_FLA ALWAYS CHAR VARIABLE Flat field position. One of IN, OUT, BLANK, CENTRE
IRIS_HND ALWAYS CHAR VARIABLE Manual wheel position. Note, was mistakenly believed to be named IRIS_MAN at one stage. Some data files may have that name in the header.
IRIS_TOP ALWAYS CHAR VARIABLE Telescope top end. One of F/15 or F/36).

(This item predates the addition of a the item TOPEND to general case. It should have the same value)
OBS_MODE OPTIONAL CHAR VARIABLE Observation mode. Used for IRIS. Values: Obs-1, Obs-2, Obs-2a, Obs-2b, Obs-2c, Obs-4
TIME_NDR OPTIONAL REAL VARIABLE NDR time for IRIS mode 2 and 4 observations.
N_READ OPTIONAL INT VARIABLE Number of NDR Iris reads
TIME_INT OPTIONAL REAL VARIABLE IRIS exposure time.
N_INT OPTIONAL INT VARIABLE IRIS number of cycles
TIME_RES OPTIONAL REAL VARIABLE IRIS exposure time resolution
AMP_OFF OPTIONAL LOGICAL VARIABLE IRIS amplifier off

Polarimeter specific items

These items are added when the Polarimeter Module is used, either with CCD or IRIS observations.

Name Present Type Value Details
POLPLATE ALWAYS VARIABLE REAL Polarimeter plate position. An angle in degrees.
POLCALIB ALWAYS VARIABLE CHAR Polarimeter calibrator position. CLEAR, CIRC, IRCIRC, HNPB, WG, HN22 or HR

2dF specific items

2dF is still undergoing rapid developlment. Existing keywords may be modified and many more are still to be added.

Name Present Type Value Details
SPECTID ALWAYS CHAR Fixed Spectrograph ID, A or B.
FOCUS ALWAYS REAL VARIABLE Camera focus (counts)
TILTSPAT ALWAYS REAL VARIABLE Camera Focus spatial tilt
TILTSPEC ALWAYS REAL VARIABLE Camera Focus spectral tilt
GRATANGL ALWAYS REAL VARIABLE Grating Angle (Degrees)
LAMBDAC ALWAYS REAL VARIABLE Central Wavelength (Angstroms)
DISPERS ALWAYS REAL VARIABLE Dispersion in Angstrom/Pixel
ORDER ALWAYS INT VARIABLE Spectrum Order
HARTMANA ALWAYS CHAR VARIABLE Hartmann shutter A
HARTMANB ALWAYS CHAR VARIABLE Hartmann shutter B
SFILT1 ALWAYS CHAR VARIABLE Lower filter wheel position
SFILT2 ALWAYS CHAR VARIABLE Upper filter wheel position
SOURCE ALWAYS CHAR VARIABLE Spectrograph source slit (Plate 0 or Plate 1)
GRATID ALWAYS CHAR VARIABLE Grating ID. values like 600V, 1200B etc.
GRATBLAZ ALWAYS CHAR VARIABLE Either COLLIMATOR or CAMERA.
GRATLPMM ALWAYS REAL VARIABLE Grating rulling lines per mm
LAMPNAME OPTIONAL REAL VARIABLE Name of lamp used for the exposure. Only present for calibration frames. It will be one of Helium, CuAr or FeAr or a combination of these separated by plus (+) signs.
TDFCTVER ALWAYS CHAR FIXED The version of the 2dF control task in use. For example, r1.0.
TDFCTDAT ALWAYS CHAR FIXED The date the 2dF control task was built.

In addition, 2dF adds a number of other items to the data files. First there is a file CLASS. This is used by the data reduction programs to work out what type file a data file is. In a figaro format file this is found in the item .MORE.NDF_CLASS and is a character string with the following possible values

Value Meaning
MFOBJECT Multi fibre object observation exposure
DARK Dark exposure
BIAS Bias exposure
MFSKY Sky exposure
LFLAT Long slit flag field exposure
MFFF Multi fibre flat field exposure
MFARC Arc exposure
MFFLX Flux calibration exposure

In addition, there is a structure which gives Fibre allocation and field details, extracted from the 2dF field configuration file and 2dF data bases. This structure found in the item .MORE.FIBRES and has three items are that level being

Item Use
FIELD A stuructre of type Fib_field which describes the field. See below for details.
OBJECT A stuructre of type Fib_object which gives the fibre allocation details. See below for details.
NUM_FIBRES An integer value giving the number of fibres. This is always 200 for 2dF data files.

The Fib_field structure type has the following contents

Item Use
LABEL Field label as per the 2dF configuration file
PROGID Program ID, as per the 2dF configuration file.
MODE Observation mode. Currently always NORMAL
FILENAME Name of configuration file, after tweaking by the 2dF control task.
ACTMJD Observation date as an MJD, i.e. the date the 2dF config file was tweaked for
UNALLOCOBJ Number of unallocated objects in the 2dF configuration file.
UNALLOCGUI Number of unallocated guide objects in the 2dF configuration file.
UNALLOCSKY Number of unallocated sky objects in the 2dF configuration file.
ALLOCOBJ Number of allocated objects in the 2dF configuration file.
ALLOCGUI Number of allocated guide objects in the 2dF configuration file.
ALLOCSKY Number of allocated sky objects in the 2dF configuration file.
CENRA Field center Mean RA in radians.
CENDEC Field center Mean Declination in radians.
CENEQNX Field center coordinates equinox, currently allways 2000.
APPRA Field center Apparent RA in radians.
APPDEC Field center Apparent Declination in radians.
APPEPOCH Epoch apparent coordinates as a MJD.
CONFIGMJD Date the file was originally configured for as a MJD.

The Fib_object structure type has the following contents, each of which is an array of 200 representing the objects for each fibre observed. The order is the Fibre ranking on the CCD.

Item Use
RA RA of object.
DEC Declination of object.
THETA Fibre Theta angle in radians.
X Fibre end actual X position in micros from the field center.
Y Fibre end actual Y position in micros from the field center.
XERR Error between fibre X and requested fibre X positions, in microns. Only valid for allocated objects with TYPE = P, F, or S).
YERR Error between fibre Y and requested fibre Y positions, in microns. Only valid for allocated objects with TYPE = P, F, or S).
PIVOT Pivot used. Range 1 to 404.
TYPE Allocation type. One of N = Not in use, U = parked, P = allocated program object fibre, F = allocated fiducial (guide) fibre, S = allocated Sky fibre.
NAME Object name as entered in configuration file. This is a character string of length 80.
COMMENTS Comments added the the user to the configuration file. This is a character string of length 80.
RETRACTOR Retractor ID. This string can be used to determine the actual retractor used for a fibre and hence trace the history of the fibre. The is a character string of length 10.
PID Program ID for this object.

The above information is converted into a FITS binary table when the data file is converted to FITS format.

TAURUS specific items

Prior to (Date To Be Determined), TAURUS did not have proper support for FITS keywords. In various modes, when run from the TAURUS control window, it adds comments to the FITS header to provide relevant information. For example, the Z offset and Charge shuffling details.

From (Date To Be Determined), assuming the upgraded software was used, the following information is available.

This first table represents items which are present all of the time.

Name Present Type Value Details
CS100EXT ALWAYS LOGICAL VARIABLE Indicates if the CS100 is under external control. If TRUE, the various CS100 items indicated in the following table are also present.
ETALON ALWAYS CHAR VARIABLE The name of the Etalon in the beam.
FILTER ALWAYS CHAR VARIABLE The name of the Focal Plane Filter in the beam
FOCUSLEN ALWAYS INT VARIABLE The TAURUS Camera Focus setting. 0 to 900 is a range of 6mm
FPFLTILT ALWAYS INT VARIABLE Focal Plane filter tilt in degrees, range 0 to 15. A value of 16 indicates the filter titl mechanisum is totally disenaged, but the tilt should still be 0.
IRISSIZE ALWAYS INT VARIABLE The size of the TAURUS IRIS, range 1 to 15 cm
PPFILTER ALWAYS CHAR VARIABLE The name of the Pupil plane filter in the beam.
TAUDAT ALWAYS CHAR FIXED The software version release date.
TAUVER ALWAYS REAL FIXED The software version number
TAU_AP ALWAYS CHAR VARIABLE The name of the Aperature in the beam
T_GAS_IN ALWAYS LOGICAL VARIABLE True if the gas inlet valve is open
T_GAS_OT ALWAYS LOGICAL VARIABLE True if the gass outlet value is open
T_PRS_ET ALWAYS INT VARIABLE The atmospheric pressure in the TAURUS etalon plane
T_PRS_OS ALWAYS INT VARIABLE The atmospheric pressure outside of TAURUS (in the cass cage)
T_RN_MD ALWAYS CHAR VARIABLE The TAURUS Run mode. Possible values are SIMPLE, indicating a simple run (no shuffling), TAURUS SHUFFLING RUN, indicating a CCD Shuffling run where the Z value/TAURUS configuration was changed during the shuffle. TAURUS+TEL SHUFFLING RUN, indicating a CCD shuffling run where the TAURUS Z value/TAURUS configuration was changed and commands were sent to the telescope. TELESCOPE SHUFFLING, indicating that a CCD shuffling run with commands sent to the telescope only.
T_TMP_ET ALWAYS REAL VARIABLE The TAURUS etalon temperature. Note that not all etalons have tempreature sensors and in this case, the value of this item will be -15)
T_TMP_FP ALWAYS REAL VARIABLE The TAURUS focal plane tempreature
T_TMP_OS ALWAYS REAL VARIABLE The tempreature outside TAURUS (in the cass cage)

The following items are only present if the CS100 was in external mode when the observation was taken. Note the extra condition on ETALON_Z

Name Present Type Value Details
CSLOOPST OPTIONAL LOGICAL VARIABLE Is the CS100 loop closed
CS_INTEG OPTIONAL LOGICAL VARIABLE Is the CS100 integration mode enabled
ETALON_X OPTIONAL INT VARIABLE The Etalon X value. Range -32768 to 32767.
ETALON_Y OPTIONAL INT VARIABLE The Etalon Y value. Range -32768 to 32767.
ETALON_Z OPTIONAL INT VARIABLE The Etalon Z value. Range -32768 to 32767. Note, this is only present for SIMPLE runs. For runs involving shuffling, this item is not present.
ETALO_XR OPTIONAL INT VARIABLE The Etalon X resistance value. Range -32768 to 32767.
ETALO_YR OPTIONAL INT VARIABLE The Etalon Y resistance value. Range -32768 to 32767.
ETALO_ZR OPTIONAL INT VARIABLE The Etalon Z resistance value. Range -32768 to 32767.
LOOPCLOS OPTIONAL LOGICAL VARIABLE True if the software is demanding that the etalon loop be closed. Note that the etalon loop may not actually be closed, due to overload conditions. See CSLOOPST for that indication
LOOPGAIN OPTIONAL INT VARIABLE The TAURUS loop gain
TIME_CON OPTIONAL INT VARIABLE The TAURUS loop time constant

The following items are only present if an etalon was being servoed when the observation was taken.

Name Present Type Value Details
ETSERVED OPTIONAL CHAR VARIABLE Indicates the name of the etalon being servoed. (Which may be different from that in the beam).

During charge shuffling, TAURUS does not output the ETALON_Z value and instead outputs additional binary data items containing information appropiate to the run. This information is found in the .MORE.FIGARO.TAURUS structure.

Item Use
CONFIGS A stuructre of type Config-struct which describes the instrunment configurations which may be accessed during a TAURUS shuffling run. Only output if TAURUS is invoked in a shufflng operation. See below for details.
SHUFDATA An array of 80 character strings. This item is used to store the charge shuffling data file (as sent to the CCD controller). There is an entry for each line in the shuffle file. This is output for any TAURUS initiated CCD shuffling run.
TELCMDS An array of 80 character strings. This item is used to store the telescope comamnds file used by the instrument sequencer micro to command the telescope during a shuffling run. There is an entry for each line in the telescope commands file. This is output for any TAURUS initiated CCD shuffling run involving Telescope operations.
Z_ARRAY A 250 element array containing the Z values used during a TAURUS CCD charge shuffling run.

This is the definition of the Config-struct item mentioned above. EAch item is a 5 element array of integers. For non-etalon items, -1 is used to indicate the item is undefined, whilst for etalon items -32768 indicates the item is undefined.

Item Use
AW The Aperature wheel position (by index) 1 to 8
EW The etalon wheel position (by index) 1 to 6
PW The pupil plane filter wheel position (by index) 1 to 8
FW The focal plane filter wheel position (by index) 1 to 8
CA The Camera focus length (0 to 900)
IN The Focal plane filter tilt (0-15 degrees, 16 = disengaged)
IR The IRIS size, 1 to 15cm
GA The CS100 loop gain, 0 - 9
TC The CS100 time contsant, 0 - 9
XS The Etalon X setting.
YS The Etalon Y setting.
ZS The Etalon Z setting.
XR The Etalon X resistance setting
YR The Etalon Y resistance setting
ZR The Etalon Z resistance setting

UCLES/UHRF Specific items

UCLES and UHRF FITS keywords were only added from Feburary 1998.

Name Present Type Value Details
GRATID ALWAYS CHAR VARIABLE The grating ID, Either 31 or 79.
SLITWIDE ALWAYS REAL VARIABLE Slit width (mm).
SLITLONG ALWAYS CHAR VARIABLE Slit length (mm). For historical reasons, mm is included in the value.
SOURCE ALWAYS CHAR VARIABLE Lamp selected, NONE=STAR
SFILT1 ALWAYS CHAR VARIABLE Star filter 1
SFILT2 ALWAYS CHAR VARIABLE Star filter 2
LFILT1 ALWAYS CHAR VARIABLE Comparison lamp filter 1
LFILT2 ALWAYS CHAR VARIABLE Comparsion lamp filter 2
BEAMDROT ALWAYS CHAR VARIABLE Beam De-rotator position, IN or OUT.
ROTANGLE ALWAYS REAL VARIABLE Rotator angle in degrees.
FOCALMOD ALWAYS CHAR VARIABLE Focal Mode setting
LAMBDAC ALWAYS REAL VARIABLE Central Wavelength (Angstroms)
BR_STATE ALWAYS CHAR VARIABLE Tracking state of the beam de-rotator, one of TRACKPA, VERTICAL or (INACTIVE).
GORDER ALWAYS INT VARIABLE Spectrum Order. Range 20 to 189
TEL_PA ALWAYS FLOAT VARIABLE Slit position angle as determined by the beam de-rotator, degrees. Only valid when BEAMDROT is IN . (Note that the standard version of this FITS keyword (above) does not appear when using the Coude Focus, so this value is inserted).

This item may become optinal at some stage when it will only appear when BEAMDROT is IN.

IRIS2 Specific items

IRIS 2 is the first instrument to be build using the new AAO UNIX/DRAMA based Observer software and the new AAO 2 CCD controllers.

A Full description of the FITS header will be posted soon.

WFI and 6dF - CICADA Based Systems

These two instruments use the ANU's CICADA CCD System. CICADA uses the NOAO keyword dicionary as the basis for most keywords used.

WFI

The Wide Field Imager for the AAT's Prime Focus Top End.

Instrument specific FITS header details will be provided soon.

6dF

The six degree field fibre facility for the UK Schmidt. The FITS header is similar to the 2dF header.

Instrument specific FITS header details will be provided soon.
Tony Farrell
Last modified: Fri Oct 27 08:08:35 EST 2000