orac016-fith Version: Draft 3 Original: 1998 May 5 Modified: 1999 May 5
This document lists the FITS headers to be created by UKIRT instrumentation, including those used by the ORAC Data Reduction pipeline.
This document specifies the ancillary data stored in FITS headers within unprocessed datasets generated by UKIRT instruments.
At present the generic headers and UFTI-specific instrument keywords are presented. The keywords associated with other instruments will be added once these are agreed. Headers for world co-ordinate systems for spectroscopic data have yet to be agreed.
This document lists the keywords, comments, data types, and allowed values for UKIRT FITS headers. It also specifies the order of the headers. The headers are arranged into groups of generic keywords common to all instruments, and groups of instrument-specific keywords. Instrument headers are currently defined for UFTI, IRCAM3, and CGS4.
An example set of FITS headers for UFTI is presented.
FITS headers in UKIRT datasets are divided into two classes: the generic information which apply to all datasets, and headers relating to specific instruments. Within each class the headers are further grouped into related information, such as astrometric, meteorological, and instrument configuration. All but the mandatory headers and specification comments are preceded by the group title written in a blank-keyword comment. All but the mandatory headers are followed by a blank line. This arrangement discriminates the various groups of keywords for easier assimilation and location of required keywords both in this document and in the datasets themselves. Astronomers will appreciate the improved readability.
The groups and their constituent header shall be the order given in this document. A complete set of headers shall comprise the generic and the appropriate instrument headers terminated by the standard END card. Data-reduction software accessing the headers, however, should, not make assumptions concerning the order of UKIRT FITS headers.
The values of certain keywords are constant. When this is the case, the value is tabulated in a column labelled 'Fixed value'.
Standard units [X-15, X-17] for keywords appear in brackets at the end of comments.
These are the mandatory headers which start the FITS file. They are described in the NOST FITS standard. [X-15] The value of BITPIX may be instrument dependent to match the output from the instrument, but BITPIX is most likely to be 32 or 16.
Keyword | Data type | Fixed value | Comment in header |
|---|---|---|---|
SIMPLE | logical | T | file does conform to FITS standard |
BITPIX | integer |
| number of bits per data pixel |
NAXIS | integer | 2 | number of data axes |
NAXIS1 | integer |
| length of data axis 1 |
NAXIS2 | integer |
| length of data axis 2 |
These are the standard FITSIO [X-16] comments referencing the FITS standard. The exact wording and number of comment lines may change in line with FITS documentation and
FITSIO. It is expected that the mandatory headers and these comments will be written
Keyword | Comment in header |
|---|---|
COMMENT | FITS (Flexible Image Transport System) format defined in Astronomy and |
COMMENT | Astrophysics Supplement Series v44/p363, v44/p371, v73/p359, v73/p365 |
COMMENT | Contact the NASA Science Office of Standards and Technology for the |
COMMENT | FITS Definition document #100 and other FITS information. |
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using FITSIO routine FTPHPR with EXTEND parameter set to false. Note that this routine does not append the blank line.
These are the FITS headers with reserved names, which qualify the data array. The value of BLANK will depend on the value of BITPIX. BLANK should not appear if BITPIX is negative. For two-byte data, BLANK is -32768; whereas for four-byte values, BLANK is -2147483648.
Keyword | Data type | Fixed value | Comment in header |
|---|---|---|---|
BSCALE | real | 1.0 | True_value = BSCALE * FITS_value + BZERO |
BZERO | real | 0.0 | True_value = BSCALE * FITS_value + BZERO |
BLANK | integer |
| Array value whose physical value is undefined |
BUNIT | character | 'ADU per integration' | Units of the primary array |
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These are the FITS headers which identify the object, and the origin and creation date of the dataset. All but OBSREF and USERID are reserved names. [X-15] To adhere to the FITS standard, OBSERVER should specify names, not initials. USERID gives a handle to the CONFIGs and EXECs used, and will be the identifier in the observation database.
Keyword | Data type | Fixed value | Comment in header |
|---|---|---|---|
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| Identification: |
TELESCOP | character | 'UKIRT, Mauna Kea, HI' | Telescope name |
INSTRUME | character |
| Instrument name |
OBSERVER | character |
| Name(s) of observer(s) |
USERID | character |
| User identification code |
OBSREF | character |
| Observer reference |
OBJECT | character |
| Name of observed object |
ORIGIN | character |
| Organisation creating the FITS file |
DATE | character |
| Date (UTC) when FITS file was created |
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The DATE keyword shall use the revised format yyyy-mm-dd from 1999 January 1, but the dd/mm/yy format before then.
The observation numbers commence at 1 for each new date of observation. A sequence of related observations, such as jittered frames, form groups. Each group has a group number, which is the observation number of the first member of the group. Within each group there is a sequence number, starting at 1.
These are the FITS headers needed by the ORAC data-reduction pipeline. [O-11] Note that these are not the only headers used by ORACDR. The choice of options for keyword OBSTYPE may be extended. STANDARD = T means this is an observation of a photometric standard for imaging data; and a ratioing standard for spectroscopy. STANDARD is is only reserved, and ignored unless OBSTYPE is "OBJECT". GRPMEM counts from 1.
Keyword | Data type | Fixed value | Comment in header |
|---|---|---|---|
|
|
| Data reduction: |
OBSNUM | integer |
| Observation number |
GRPNUM | integer |
| The number of the group applied to all members |
GRPMEM | integer |
| Sequence number of a member of a group |
GRPMAX | integer |
| Maximum number of group members, 0=arbitrary |
OBSTYPE | character |
| Type (BIAS | DARK | ARC | FLAT | OBJECT | SKY) |
STANDARD | logical |
| Whether or not the object is a standard |
RECIPE | character |
| Name of data-reduction recipe to be used |
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These are the FITS headers which record the time of the observation, identify the direction the telescope was pointing, the plate scale, the orientation of the detector, telescope and crosshead offsets, and airmass.
Unfortunately, because of the continuing debate concerning astrometric or world co-ordinate systems (WCS) in FITS, there is still no standard even for the simple tangent-plane image of the sky. What there is fails to address the problem of spectroscopic data, where the raw image from the detector is two dimensional, but the astrometric co-ordinate system is three dimensional (two sky co-ordinates, and pixel or wavelength in the dispersion direction). However, some concensus was reached at the 1998 ADASS conference, and recently three new papers have appeared, including one on spectroscopic co-ordinates. These are expected to be approved at the 1999 ADASS conference.
Once there is a FITS WCS agreement, UKIRT should adopt it. In the meantime, we shall use the widely recognised AIPS-style headers. Note that these only apply to imaging. Headers for spectroscopic data are TBD.
The DATE-OBS and DATE_END keywords shall use the revised time format yyyy-mm-ddThh:mm:ssZ.
TBD: The offset and zero points (keywords RABASE to TDECOFF below) may need to change to be consistent with the future crosshead system, not the current one.
Keyword | Data type | Fixed value | Comment in header |
|---|---|---|---|
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| Astrometric and Time Information: |
DATE-OBS | character |
| Date and time (UTC) of start of observation |
DATE-END | character |
| Date and time (UTC) of end of observation |
EQUINOX | real | 2000.0 | Equinox of object position FK5 [years] |
CTYPE1 | character | 'RA---TAN ' | Equatorial tangent-plane projection |
CRPIX1 | real |
| Pixel at reference point along axis 1 |
CRVAL1 | real |
| RA at reference point [deg] |
CDELT1 | real |
| Increment per pixel at reference point [deg] |
CUNIT1 | character | 'deg ' | Physical units of axis 1 |
CTYPE2 | character | 'DEC--TAN ' | Equatorial tangent-plane projection |
CRPIX2 | real |
| Pixel at reference point along axis 2 |
CRVAL2 | real |
| Declination at reference point |
CDELT2 | real |
| Incerement per pixel at reference point [deg] |
CROTA2 | real |
| Angle of Dec axis wrt axis 2 measured ccw [deg] |
CUNIT2 | character | 'deg ' | Physical units of axis 2 |
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RABASE | real |
| Offset zero point in RA, FK5 [deg] |
DECBASE | real |
| Offset zero point in Dec, FK5 [deg] |
XRAOFF | real |
| Crosshead offset in RA at equinox [arcsec] |
XDECOFF | real |
| Crosshead offset in Dec at equinox [arcsec] |
TRAOFF | real |
| Telescope offset in RA at equinox [arcsec] |
TDECOFF | real |
| Telescope offset in Dec at equinox [arcsec] |
AMSTART | real |
| Airmass at the start of the observation |
AMEND | real |
| Airmass at the end of the observation |
UTSTART | real |
| Start UTC of observation (DR efficiency) [h] |
UTEND | real |
| End UTC of observation (DR efficiency) [h] |
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These FITS headers specify the meteorological conditions and the dome environment.
Keyword | Data type | Fixed value | Comment in header |
|---|---|---|---|
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| Environment: |
AIR_TEMP | real |
| External air temperature in degrees Celsius |
DOMETEMP | real |
| Dome air temperature in degrees Celsius |
HUMIDITY | real |
| Percentage air humidity |
WIND_SPD | real |
| Wind speed [km/h] |
WIND_DIR | real |
| Wind direction, azimuth [deg] |
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These headers specify the configuration of the UFTI instrument, and include ancillary data needed by the data-reduction system. At present there are no plans for polarimetry or Fabry-Perot interometry with UFTI; however, keywords WPLANGLE, FP_X, FP_Y, and FP_Z are defined should either eventuality arise. Values for these keywords when the Wollaston prism or Fabry-Perot etalon are absent are TBD. The options for keyword READ_TYP may be extended.
Keyword | Data type | Fixed value | Comment in header |
|---|---|---|---|
|
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| Instrument Configuration: |
EXP_TIME | real |
| Exposure time for each co-add [s] |
INT_TIME | real |
| Total integration time (sum of all co-adds) [s] |
NEXP | integer |
| Number of exposures in the integration |
MODE | character |
| Observing mode (STARE | NDSTARE | 10-NDSTARE) |
SPD_GAIN | character |
| Readout speed (normal | fast) or high gain |
GAIN | real |
| Electrons per data number |
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FILTER | character |
| Combined filter name |
FILTER1 | character |
| Filter in wheel 1 |
FILTER2 | character |
| Filter in wheel 2 |
WPLANGLE | real |
| IRPOL waveplate angle [deg] |
FP_X | integer |
| Fabry-Perot x setting |
FP_Y | integer |
| Fabry-Perot y setting |
FP_Z | integer |
| Fabry-Perot z setting |
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DETECTOR | character |
| Detector array used |
DROWS | integer |
| Number of detectors in a row |
DCOLUMNS | integer |
| Number of detectors in a column |
RDOUT_X1 | integer |
| Start column of array readout |
RDOUT_X2 | integer |
| End column of array readout |
RDOUT_Y1 | integer |
| Start row of array readout |
RDOUT_Y2 | integer |
| End row of array readout |
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This is a list of the UFTI instrument status and engineering data, unlikely to be of use to astronomers processing the dataset. At the time of writing, this list may not be complete, and some keyword names may change.
Keyword | Data type | Fixed value | Comment in header |
|---|---|---|---|
|
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| Engineering |
CNFINDEX | integer |
| Index increments when hardware config. changes |
TEMP_ARR | real |
| Temperature of array [K] |
TEMP_TAB | real |
| Temperature of UFTI table [K] |
TEMP_ST1 | real |
| Temperature of UFTI cooler stage 1 [K] |
TEMP_ST2 | real |
| Temperature of UFTI cooler stage 2 [K] |
TFOCUS | real |
| Telescope focus position [mm] |
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V1 | real |
| UFTI -15V supply [V] |
V2 | real |
| UFTI -9 V supply [V] |
V3 | real |
| UFTI -5 V supply [V] |
V4 | real |
| UFTI +30 V supply [V] |
V5 | real |
| UFTI +15 V supply [V] |
V6 | real |
| UFTI +9 V supply [V] |
V7 | real |
| UFTI +5 V supply [V] |
V8 | real |
| UFTI Digital [V] |
V13 | real |
| UFTI Analog in [V] |
SENS | real |
| UFTI temperature sensor on motherboard [K] |
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These headers specify the configuration of the IRCAM3 instrument, and include ancillary data needed by the data-reduction system. DROWS and DCOLUMNS specify the full dimensions of the detector array. The options for keyword READ_TYP may be extended.
Keyword | Data type | Fixed value | Comment in header |
|---|---|---|---|
|
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| Instrument Configuration: |
EXP_TIME | real |
| Exposure time for each co-add [s] |
INT_TIME | real |
| Total integration time (sum of all co-adds) [s] |
NEXP | integer |
| Number of exposures in the integration |
NEXP_PH | integer |
| Number of exposures in each chop phase |
MODE | character |
| Observing mode (STARE | ND_STARE) |
READ_TYP | character |
| Type of readout (standard | fast | deepwell) |
GAIN | real |
| Electrons per data number |
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FILTER | character |
| Combined filter name |
FILTER1 | character |
| Filter in wheel 1 |
FILTER2 | character |
| Filter in wheel 2 |
MAGNIFIC | real |
| Magnifier factor (1.0 means magnifier is out) |
CHOPDIFF | logical |
| Whether or not main-offset beam value stored |
IF_SHARP | logical |
| Whether or not shift and add enabled |
LINEAR | logical |
| Whether or not linearisation enabled |
WPLANGLE | real |
| IRPOL waveplate angle [deg] |
FP_X | integer |
| Fabry-Perot x setting |
FP_Y | integer |
| Fabry-Perot y setting |
FP_Z | integer |
| Fabry-Perot z setting |
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DETECTOR | character |
| Detector array used |
DROWS | integer |
| Number of detectors in a row |
DCOLUMNS | integer |
| Number of detectors in a column |
RDOUT_X1 | integer |
| Start column of array readout |
RDOUT_X2 | integer |
| End column of array readout |
RDOUT_Y1 | integer |
| Start row of array readout |
RDOUT_Y2 | integer |
| End row of array readout |
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This is a list of the IRCAM3 instrument status and engineering data, unlikely to be of use to astronomers processing the dataset.
Keyword | Data type | Fixed value | Comment in header |
|---|---|---|---|
|
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| Engineering: |
CNFINDEX | integer |
| Index increments when hardware config. changes |
TEMP_ARR | real |
| Temperature of array [K] |
TEMP_ST1 | real |
| Temperature of cooler stage 1 [K] |
TEMP_ST2 | real |
| Temperature of cooler stage 2 [K] |
TFOCUS | real |
| Telescope focus position [mm] |
DFOCUS | real |
| Detector focus |
RESET_DL | real |
| NDR reset delay [s] |
CHOP_DEL | real |
| Chop delay [s] |
READ_INT | real |
| NDR read interval [s] |
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CLOCK0 | real |
| ALICE CLOCK0 voltage [V] |
CLOCK1 | real |
| ALICE CLOCK1 voltage [V] |
CLOCK2 | real |
| ALICE CLOCK2 voltage [V] |
CLOCK3 | real |
| ALICE CLOCK3 voltage [V] |
CLOCK4 | real |
| ALICE CLOCK4 voltage [V] |
CLOCK5 | real |
| ALICE CLOCK5 voltage [V] |
CLOCK6 | real |
| ALICE CLOCK6 voltage [V] |
VSLEW | real |
| ALICE VSLEW voltage [V] |
VDET | real |
| ALICE VDET voltage [V] |
DET_BIAS | real |
| ALICE DET_BIAS voltage [V] |
VDDUC | real |
| ALICE VDDUC voltage [V] |
VDETGATE | integer |
| ALICE VDETGATE voltage [V] |
VGG_A | real |
| ALICE VGG_ACTIVE voltage [V] |
VGG_INA | real |
| ALICE VGG_INACTIVE voltage [V] |
VDDOUT | real |
| ALICE VDDOUT voltage [V] |
V3 | real |
| ALICE V3 voltage [V] |
VLCLR | real |
| ALICE VLCLR voltage [V] |
VLD_A | real |
| ALICE VLOAD active voltage [V] |
VLD_INA | real |
| ALICE VLOAD_INACTIVE voltage [V] |
WFREQ | real |
| ALICE waveform state frequency [Mhz] |
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These headers specify the configuration of the CGS4 instrument, and include ancillary data needed by the data-reduction system. Note that the end row and column of the readout are given by RLBOUND2+NAXIS2-1 and RLBOUND1+NAXIS1-1 respectively. DROWS and DCOLUMNS specify the full dimensions of the detector array.
Although PA_SLIT (formerly PA) is included, I'd like to see this information eventually part of the world co-ordinate system.
Keyword | Data type | Fixed value | Comment in header |
|---|---|---|---|
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| Instrument Configuration: |
EXP_TIME | real |
| Exposure time for each co-add [s] |
INT_TIME | real |
| Total integration time (sum of all co-adds) [s] |
NEXP | integer |
| Number of exposures in the integration |
NEXP_PH | integer |
| Number of exposures in each chop phase |
NINT | integer |
| Number of integrations in the observation |
MODE | character |
| Observing mode (STARE|ND_STARE|CHOP|ND_CHOP) |
READ_TYP | character |
| Type of readout (standard | fast | deepwell) |
GAIN | real |
| Electrons per data number |
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FILTER | character |
| Combined filter name |
FILTER1 | character |
| Filter in wheel 1 |
FILTER2 | character |
| Filter in wheel 2 |
SWIDTH | real |
| Width of slit [pixel] |
PA_SLIT | real |
| Position angle of the slit on the sky [deg] |
GRATING | character |
| Name of grating |
GLAMBDA | real |
| Requested grating wavelength [um] |
CNFINDEX | integer |
| Index increments when hardware config. changes |
GANGLE | real |
| Grating angle [deg] |
GORDER | integer |
| Grating order |
GDISP | real |
| Grating dispersion [um/pixel] |
CVF | character |
| Name of CVF |
CLAMBDA | real |
| CVF wavelength [um] |
LAMP | character |
| Name of calibration lamp (off means no lamp) |
BBTEMP | real |
| Black-body temperature [K] |
DETINCR | real |
| Increment between scan positions [pixel] |
DETNINCR | integer |
| Number of scan positions in scan |
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PEAK_ROW | integer |
| Pixel index of peakup row |
PBOX_XL | integer |
| Lower x pixel-index bound of peakup box |
PBOX_XU | integer |
| Upper x pixel-index bound of peakup box |
PBOX_YL | integer |
| Lower y pixel-index bound of peakup box |
PBOX_YL | integer |
| Upper y pixel-index bound of peakup box |
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CHOPDIFF | logical |
| Whether or not main-offset beam value stored |
IF_SHARP | logical |
| Whether or not shift and add enabled |
LINEAR | logical |
| Whether or not linearisation enabled |
WPLANGLE | real |
| IRPOL waveplate angle [deg] |
FP_X | integer |
| Fabry-Perot x setting |
FP_Y | integer |
| Fabry-Perot y setting |
FP_Z | integer |
| Fabry-Perot z setting |
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DETECTOR | character |
| Detector array used |
DROWS | integer |
| Number of detectors in a row |
DCOLUMNS | integer |
| Number of detectors in a column |
RDOUT_X1 | integer |
| Start column of array readout |
RDOUT_X2 | integer |
| End column of array readout |
RDOUT_Y1 | integer |
| Start row of array readout |
RDOUT_Y2 | integer |
| End row of array readout |
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This is a list of the CGS4 instrument status and engineering data, unlikely to be of use to astronomers processing the dataset.
Keyword | Data type | Fixed value | Comment in header |
|---|---|---|---|
|
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| Engineering: |
TEMP_ARR | real |
| Temperature of array [K] |
RESET_DL | real |
| NDR reset delay [s] |
TEMP_ST1 | real |
| Temperature of cooler stage 1 [K] |
TEMP_ST2 | real |
| Temperature of cooler stage 2 [K] |
TFOCUS | real |
| Telescope focus position [mm] |
DFOCUS | real |
| Detector focus |
CHOP_DEL | real |
| Chop delay [s] |
READ_INT | real |
| NDR read interval [s] |
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SANGLE | real |
| Angle of slit wrt ? [deg] |
SLIT | character |
| Name of the slit |
SLENGTH | real |
| Slit length [mm] |
DENCBASE | integer |
| Zeropoint (steps) of detector translation |
IRTANGLE | real |
| Image rotator angle [deg] |
CALAPER | real | 10 | Aperture of tungsten-halogen lamp (%) |
THLEVEL | integer |
| Level of tungsten-halogen lamp |
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CLOCK0 | real |
| ALICE CLOCK0 voltage [V] |
CLOCK1 | real |
| ALICE CLOCK1 voltage [V] |
CLOCK2 | real |
| ALICE CLOCK2 voltage [V] |
CLOCK3 | real |
| ALICE CLOCK3 voltage [V] |
CLOCK4 | real |
| ALICE CLOCK4 voltage [V] |
CLOCK5 | real |
| ALICE CLOCK5 voltage [V] |
CLOCK6 | real |
| ALICE CLOCK6 voltage [V] |
VSLEW | real |
| ALICE VSLEW voltage [V] |
VDET | real |
| ALICE VDET voltage [V] |
DET_BIAS | real |
| ALICE DET_BIAS voltage [V] |
VDDUC | real |
| ALICE VDDUC voltage [V] |
VDETGATE | integer |
| ALICE VDETGATE voltage [V] |
VGG_A | real |
| ALICE VGG_ACTIVE voltage [V] |
VGG_INA | real |
| ALICE VGG_INACTIVE voltage [V] |
VDDOUT | real |
| ALICE VDDOUT voltage [V] |
V3 | real |
| ALICE V3 voltage [V] |
VLCLR | real |
| ALICE VLCLR voltage [V] |
VLD_A | real |
| ALICE VLOAD active voltage [V] |
VLD_INA | real |
| ALICE VLOAD_INACTIVE voltage [V] |
WFREQ | real |
| ALICE waveform state frequency [Mhz] |
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These headers specify the configuration of the Michelle instrument, and include ancillary data needed by the data-reduction system.
Keyword | Data type | Fixed value | Comment in header |
|---|---|---|---|
|
|
| Instrument Configuration: |
EXP_TIME | real |
| Exposure time for each co-add [s] |
INT_TIME | real |
| Total integration time (sum of all co-adds) [s] |
NEXP | integer |
| Number of exposures in the integration |
NEXP_PH | integer |
| Number of exposures in each chop phase |
NINT | integer |
| Number of integrations in the observation |
MODE | character |
| Observing mode (STARE|ND_STARE|CHOP|ND_CHOP) |
READ_TYP | character |
| Type of readout (standard | fast | deepwell) |
GAIN | real |
| Electrons per data number |
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|
|
FILTER | character |
| Combined filter name |
FILTER1 | character |
| Filter in wheel 1 |
FILTER2 | character |
| Filter in wheel 2 |
SWIDTH | real |
| Width of slit [pixel] |
PA_SLIT | real |
| Position angle of the slit on the sky [deg] |
GRATING | character |
| Name of grating |
GLAMBDA | real |
| Requested grating wavelength [um] |
CNFINDEX | integer |
| Index increments when hardware config. changes |
GANGLE | real |
| Grating angle [deg] |
GORDER | integer |
| Grating order |
GDISP | real |
| Grating dispersion [um/pixel] |
CVF | character |
| Name of CVF |
CLAMBDA | real |
| CVF wavelength [um] |
LAMP | character |
| Name of calibration lamp (off means no lamp) |
BBTEMP | real |
| Black-body temperature [K] |
DETINCR | real |
| Increment between scan positions [pixel] |
DETNINCR | integer |
| Number of scan positions in scan |
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PEAK_ROW | integer |
| Pixel index of peakup row |
PBOX_XL | integer |
| Lower x pixel-index bound of peakup box |
PBOX_XU | integer |
| Upper x pixel-index bound of peakup box |
PBOX_YL | integer |
| Lower y pixel-index bound of peakup box |
PBOX_YL | integer |
| Upper y pixel-index bound of peakup box |
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CHOPDIFF | logical |
| Whether or not main-offset beam value stored |
IF_SHARP | logical |
| Whether or not shift and add enabled |
LINEAR | logical |
| Whether or not linearisation enabled |
WPLANGLE | real |
| IRPOL waveplate angle [deg] |
FP_X | integer |
| Fabry-Perot x setting |
FP_Y | integer |
| Fabry-Perot y setting |
FP_Z | integer |
| Fabry-Perot z setting |
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DETECTOR | character |
| Detector array used |
DROWS | integer |
| Number of detectors in a row |
DCOLUMNS | integer |
| Number of detectors in a column |
RDOUT_X1 | integer |
| Start column of array readout |
RDOUT_X2 | integer |
| End column of array readout |
RDOUT_Y1 | integer |
| Start row of array readout |
RDOUT_Y2 | integer |
| End row of array readout |
|
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|
|
This is a list of the Michelle instrument status and engineering data, unlikely to be of use to astronomers processing the dataset.
Keyword | Data type | Fixed value | Comment in header |
|---|---|---|---|
|
|
| Engineering: |
TEMP_ARR | real |
| Temperature of array [K] |
RESET_DL | real |
| NDR reset delay [s] |
TEMP_ST1 | real |
| Temperature of cooler stage 1 [K] |
TEMP_ST2 | real |
| Temperature of cooler stage 2 [K] |
TFOCUS | real |
| Telescope focus position [mm] |
DFOCUS | real |
| Detector focus |
CHOP_DEL | real |
| Chop delay [s] |
READ_INT | real |
| NDR read interval [s] |
|
|
|
|
SANGLE | real |
| Angle of slit wrt ? [deg] |
SLIT | character |
| Name of the slit |
SLENGTH | real |
| Slit length [mm] |
DENCBASE | integer |
| Zeropoint (steps) of detector translation |
IRTANGLE | real |
| Image rotator angle [deg] |
CALAPER | real | 10 | Aperture of tungsten-halogen lamp (%) |
THLEVEL | integer |
| Level of tungsten-halogen lamp |
|
|
|
|
CLOCK0 | real |
| ALICE CLOCK0 voltage [V] |
CLOCK1 | real |
| ALICE CLOCK1 voltage [V] |
CLOCK2 | real |
| ALICE CLOCK2 voltage [V] |
CLOCK3 | real |
| ALICE CLOCK3 voltage [V] |
CLOCK4 | real |
| ALICE CLOCK4 voltage [V] |
CLOCK5 | real |
| ALICE CLOCK5 voltage [V] |
CLOCK6 | real |
| ALICE CLOCK6 voltage [V] |
VSLEW | real |
| ALICE VSLEW voltage [V] |
VDET | real |
| ALICE VDET voltage [V] |
DET_BIAS | real |
| ALICE DET_BIAS voltage [V] |
VDDUC | real |
| ALICE VDDUC voltage [V] |
VDETGATE | integer |
| ALICE VDETGATE voltage [V] |
VGG_A | real |
| ALICE VGG_ACTIVE voltage [V] |
VGG_INA | real |
| ALICE VGG_INACTIVE voltage [V] |
VDDOUT | real |
| ALICE VDDOUT voltage [V] |
V3 | real |
| ALICE V3 voltage [V] |
VLCLR | real |
| ALICE VLCLR voltage [V] |
VLD_A | real |
| ALICE VLOAD active voltage [V] |
VLD_INA | real |
| ALICE VLOAD_INACTIVE voltage [V] |
WFREQ | real |
| ALICE waveform state frequency [Mhz] |
|
|
|
|
SIMPLE = T / file does conform to FITS standard
BITPIX = 32 / number of bits per data pixel
NAXIS = 2 / number of data axes
NAXIS1 = 1024 / length of data axis 1
NAXIS2 = 1024 / length of data axis 2
COMMENT FITS (Flexible Image Transport System) format defined in Astronomy and
COMMENT Astrophysics Supplement Series v44/p363, v44/p371, v73/p359, v73/p365.
COMMENT Contact the NASA Science Office of Standards and Technology for the
COMMENT FITS Definition document #100 and other FITS information.
BSCALE = 1.0 / True_value = BSCALE * FITS_value + BZERO
BZERO = 0.0 / True_value = BSCALE * FITS_value + BZERO
BLANK = -2147483648 / Array value whose physical value is undefined
BUNIT = 'ADU per integration' / Units of the primary array
Identification:
TELESCOP= 'UKIRT, Mauna Kea, HI' / Telescope name
INSTRUME= 'UFTI ' / Instrument
OBSERVER= 'S K Leggett' / Observer name(s)
USERID = 'SKL ' / User identification code
OBSREF = 'AIC/service' / Observer reference
OBJECT = '3C 65 ' / Name of observed object
ORIGIN = 'JAC, Hilo, Hawaii' / Organisation creating the FITS file
DATE = '1999-10-22' / Date (UTC) when FITS file was created
Data reduction:
OBSNUM = 99 / Observation number
GRPNUM = 95 / The number of the group applied to all members
GRPMEM = 5 / Sequence number of a member of a group
GRPMAX = 9 / Maximum number of group members, 0=arbitrary
OBSTYPE = 'OBJECT ' / Type (BIAS|DARK|ARC|FLAT|OBJECT|SKY)
STANDARD= F / Whether or not the object is a standard
RECIPE = 'QUADRANT_JITTER' / Data reduction recipe to be used
Astrometric and time information:
DATE-OBS= '1999-10-22T13:24:35Z' / Date and time (UTC) of start of observation
DATE-END= '1999-10-22T13:25:39Z' / Date and time (UTC) of end of observation
EQUINOX = 2000.0 / Equinox of object position FK5 [years]
CTYPE1 = 'RA---TAN' / Equatorial tangent-plane projection
CRPIX1 = 512.5 / Pixel at reference point along axis 1
CRVAL1 = 52.9533 / RA at reference point [deg]
CDELT1 = 0.0000247 / Increment per pixel at reference point [deg]
CUNIT1 = 'deg ' / Physical units of axis 1
CTYPE2 = 'DEC--TAN' / Equatorial tangent-plane projection
CRPIX2 = 512.5 / Pixel at reference point along axis 2
CRVAL2 = 23.4567 / Declination at reference point [deg]
CDELT2 = 0.0000247 / Increment per pixel at reference point [deg]
CUNIT2 = 'deg ' / Physical units of axis 2
CROTA2 = -1.1 / Angle of Dec axis wrt axis 2 measured ccw [deg]
RABASE = 3.52986 / Offset zero-point in RA, FK5 [h]
DECBASE = 23.4617 / Offset zero-point in Dec, FK5 [deg]
XRAOFF = 17.7 / Crosshead offset RA at equinox [arcsec]
XDECOFF = -18.1 / Crosshead offset Dec at equinox [arcsec]
TRAOFF = 18.0 / Telescope offset RA at equinox [arcsec]
TDECOFF = -18.0 / Telescope offset Dec at equinox [arcsec]
AMSTART = 1.628028 / Airmass at start of observation
AMEND = 1.628071 / Airmass at end of observation
UTSTART = 13.40972 / Start UTC of observation (DR efficiency) [h]
UTEND = 13.42750 / End UTC of observation (DR efficiency) [h]
Environment:
AIR_TEMP= 2.6 / External air temperature in degrees Celsius
DOMETEMP= 3.2 / Dome air temperature in degrees Celsius
HUMIDITY= 13.5 / Percentage air humidity
WIND_SPD= 7.3 / Wind speed [km/h]
WIND_DIR= 123 / Wind direction, azimuth [deg]
Instrument configuration:
EXP_TIME= 10.0 / Exposure time for each co-add [s]
INT_TIME= 60.0 / Total integration time (sum of all co-adds) [s]
NEXP = 6 / Number of exposures in the integration
MODE = 'STARE ' / Observing mode (STARE | NDSTARE | 10-NDSTARE)
SPD_GAIN= 'Normal ' / Readout speed (normal | fast) or high gain
GAIN = 6 / Electrons per data number
FILTER = 'K ' / Combined filter name
FILTER1 = 'Open ' / Filter in wheel 1
FILTER2 = 'Kocli ' / Filter in wheel 2
WPLANGLE= 0 / IRPOL waveplate angle [deg]
FP_X = 0 / Fabry-Perot x setting
FP_Y = 0 / Fabry-Perot y setting
FP_Z = 0 / Fabry-Perot z setting
DETECTOR= 'haw042 ' / Detector array used
DROWS = 1024 / Number of detectors in a row
DCOLUMNS= 1024 / Number of detectors in a column
RDOUT_X1= 1 / Start column of array read-out
RDOUT_X2= 1024 / End column of array read-out
RDOUT_Y1= 1 / Start row of array read-out
RDOUT_Y2= 1024 / End row of array read-out
Engineering:
CNFINDEX= 192 / Index increments when hardware config. changes
TEMP_ARR= 4.0 / Temperature of array [K]
TEMP_TAB= 15.5 / Temperature of UFTI table [K]
TEMP_ST1= 9.4 / Temperature of UFTI cooler stage 1 [K]
TEMP_ST2= 4.7 / Temperature of UFTI cooler stage 2 [K]
TFOCUS = 2.06 / Telescope focus position [mm]
V1 = -11.1 / UFTI -15 V supply [V]
V2 = -9.4 / UFTI -9 V supply [V]
V3 = -5.2 / UFTI -5 V supply [V]
V4 = 23.2 / UFTI +30 V supply [V]
V5 = 12.2 / UFTI +15 V supply [V]
V6 = 9.4 / UFTI +9 V supply [V]
V7 = 5.1 / UFTI +5 V supply [V]
V8 = 4.9 / UFTI Digital [V]
V13 = -0.1 / UFTI Analog in [V]
SENS3 = -273.0 / UFTI temperature sensor on motherboard [K]
END
Thanks to Sandy Leggett, Nick Rees, Maren Purves, Alan Bridger, Gillian Wright, and Tom Kerr for helpful discussions on earlier versions of this document, and for providing details of the instrument-specific headers.