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ALFOSC Sequencer Command Documentation

Go to the SEQUENCER Reference Manual Main Page.

Instrument : ALFOSC
Observing Mode: ANY IMA SPEC POL
Description: SHORT LONG

alfosc imexam Initiates an IRAF imexam session on the image currently loaded into the ALFOSC DS9. While active in the imexam session, no further commands can be issued from the sequencer window. To kill the imexam session type q on the image in the postprocessing display.


?       Print help
a       Aperture radial photometry measurement (see above for output)
c       Column plot
e       Contour plot
f       Redraw the last graph
j       Fit 1D gaussian to image lines
k       Fit 1D gaussian to image columns
l       Line plot
m       Statistics
            image[section] npixels mean median stddev min max
q       Quit
r       Radial profile plot (see above for output)
s       Surface plot
x       Print coordinates
            col line pixval [xorign yorigin dx dy r theta]
alfosc log-comment "Comment in quotes" [file1 file2 ...] When invoked with just the comment, it will be applied to the latest available image with a prefix for the current night (which starts at noon) and the sequencer's instrument.

If image names are provided, the program will test the existence of ALL them before applying the change.


        $ alfosc.log-comment "This is a comment"
        $ alfosc.log-comment "Comment for two" ALug170154 ALug170155
Notice that there's no need to add the ".fits" after each image's name

If no arguments are provided, a usage message is displayed

alfosc object [-d] <text> Sets the FITS keyword OBJECT to <text>. DATA
alfosc photstd [-e] [-a mode] [-f filterIDs] Automatic exposure of standard stars. Goes to nearest standard field and does exposures in filters UBVRi as default - or filters specified by the user.
Currently supports UBVRi and in the future sdss ugriz. Other filters can be done, but will have the same exposure times, set by the variable default_time.
Instead of going to the nearest field, aquisition mode can be set to a specific target. The TCS name must be used, see

Usage example: alfosc.photstd -a A_PG1633+099 -f "74 75 120 110"

alfosc qicpol [<2ndfile>] Circular polarimetry quick-look tool (FAPOL+ calcite) which calculates the circular polarization from a set of two images (retarder plate positions 0 and 90.0 degrees). The flux of each image is measured with fixed aperture using iraf/apphot from raw images. See more detailed description of the script from here DATA
alfosc qilpol [<4thfile>] Linear polarimetry quick-look tool (FAPOL+ calcite) which calculates the linear polarization from a set of four images (retarder plate positions 0, 22.5 45 and 67.5 degrees). The flux of each image is measured with fixed aperture using iraf/apphot from raw images. See more detailed description of the script from here. DATA
alfosc quickspec [<file>] Extracts spectra and applies an approximate wavelength calibration on an ALFOSC spectroscopic image using the iraf tasks apall and dispcor. If no file is specified, spectral extraction from the last image written to disk will be attempted. Extracted spectra are kept in the directory /data/reduced/alfosc/ on the instrument computer. Existing spectra will be overwritten if the task is re-run on the same file. The wavelength calibration is done using standard wavelength settings for the standard horizontally oriented central slits. The wavelength calibration is only approximate, and is most likely based on a slit that you are not currently using. Note that the slits have different Y-positions and hence different wavelength zeropoints, and that hence zeropoint offsets of for instance 200 Ångström are normal. The quickspec will leave the user in an IRAF splot session. To kill the session type q in the postprocessing graphics window. There are 2 ways of initiating quickspec. Automatic (see command quickspec-config auto=yes below), and from the sequencer command line. * When called from the sequencer command line, all input and output will go through that sequencer terminal. * When automatic, the input and output goes through the BIAS 'command' window. DATA
alfosc quickspec-config [<options>] Use this command to set the IRAF apall task parameters used in the quickspec script.
   auto=[yes|no] : Automatically run quickspec on incoming images
   kill=[yes|no] : Automatically remove previous quickspec windows
   default : loads default values.
Below parameters are specific for the apal iraf task:
   nfind=[1-10] (useful for Echelle spectra, MOS spectra, spectropolarimetry, and longslit spectra with more than one object on the slit)

If the command is issued without any options, current parameter settings will be listed.

alfosc rempath [-d] <nn> Sets the remote saving path to <nn>. DATA
alfosc remsave_off [-d] Turns off remote saving. DATA
alfosc remsave_on [-d] Turns on remote saving. DATA
alfosc reset-log The script will use infosys.kill to reset the monitoring system, then it will wait for a set number of seconds, and at last it will instruct the obslog to show the listing for alfosc, all the while informing the user about what is happening

If there's any error, the script will notify the user and suggest further actions.
alfosc slitrot Uses the currently loaded DS9 image to compute the TCS field rotation angle required to align two objects along a slit. The targets are identified interactively by the user through an imexam session. DATA

In scripts, the syntax alfosc.<command> should be used.
If a part of a command is written in <angle brackets>, this is an argument that should be replaced with a value.
If a part of a command is written in [square brackets], this is an optional argument or flag.
When available, the optional flag -d will write extended debugging information to the log.
When available, the optional flag -e will show the script on standard output instead of executing the commands.
When available, the optional flag -t will only make a simulated exposure. Useful for testing scripts.

Type definitions:
DATA: All commands related to handling/modifying data (editing fits-headers, post-processing etc.).
DET: Commands related to operations with the detector.
DISP: Commands related to displaying images on the instrument computer.
INST: Commands related to operations with the instrument.
TEL: Commands related to operations with the telescope.

Back to top Last modified: November 23 2011