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spec2big

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spec2big

spec2big converts extracted spectra from extensions format to equispec format.


USAGEspec2big framename
INPUTframename_2spec.fits are the set of image files to be combined
OUTPUT
framename_big.fits is the spectral frame
framename_sig.fits is the noise frame
PARAMETERSnone


Details:

spec2big converts extracted spectra from extensions format to equispec format. The spectra and noise are separated into two files. Standard equispec header keywords are used for compatibility in programs such as IRAF.

The header of all the spectra contains the following parameters:

N_SLITS  = number of slits extracted
D_SLIT   = interval along slit, in arc seconds
CRVAL1   = wavelength of first pixel
CDELT1   = wavelength interval of pixels
CRPIX1   = starting pixel
EXPTIME  = total exposure time of the spectrum
SHUFFLED = does data included shuffled region?
NOD      = nod distance, in pixels (for N&S; data)

Each spectrum has the following header keywords:

OBJxxx    = object name, as defined in the SMF file for the mask
APNUMxxx  = additional aperture information
CNTRLxxx  = the line in the 2-d spectrum centered on the object 
CSECTxxxA = lower 2d spectra region in pixels
CSECTxxxB = upper 2d spectra region in pixels

Additional standard header keywords:

WAT0_001
WAT1_001
WAT2_001
WAT3_001
WCSDIM
DC-FLAG 
CTYPE1
LTM1_1
CD1_1
CTYPE2
LTM2_2
CD2_2
CTYPE3
LTM3_3
CD3_3


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