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Extracting 2-D spectra

Before running extract-2dspec, we make sure the parameters are set properly:
editpar extract-2dspec

type q to end

deltalam              2.037000       wavelength step
deltaslit             0.200000       slit postion interval in arcseconds
telscale              2.899000       telescope scale sec per mm
search                       0       half width of search region
trace                     none       spectrum trace method
trace_order                  3       order of fit to spectrum trace
align                     none       alignment method
obj_frac              0.300000       fraction of galaxies used for alignment
init_off              0.000000       initial object offset guess, in pixels
minlambda           4800.000000       min wavelength of extraction
maxlambda           7800.000000       max wavelength of extraction
sub_ns                       n       subtract shuffled region of n&s; data?
sampling                linear       linear or log sampling
edge                         0       excluded edge of spectrum
use_holes                    y       extract alignment stars?

Then we run the commands to generate the ift0009_2spec.fits and ift0010_2spec.fits, respectively.
extract-2dspec -m ift0012 -f ift0009_s
extract-2dspec -m ift0012 -f ift0010_s

Finally, we can use sumspec to stack the spectra and do some cosmic ray cleaning. The following command will generate CSIfld5_2spec.fits:

sumspec -o CSIfld5_2spec ift0009 ift0010

Next: Viewing the Spectra Up: Reducing the Spectra Previous: Run Sky-Subtraction on the Science Exposures   Contents

Edward Villanueva 2014-08-27