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esky2det (esky2det-1.12) [xmmsas_20060628_1801-7.0.0]

Description Description FITS file position IO. Home Index

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Command-line position entry.

The sky position of a single source may be entered via the parameters ra, dec and (optionally) errorradius. These are parameters of type angle and can therefore be provided in a variety of formats. Eg:

ra=32h06m19.6s dec=-07d44m56.7s errorradius=00d00m01.0s

See the task param documentation for further details.

In this mode, the output positions are printed to a single line of standard output. The format of this output line is given in the following examples.

  1. Example 1: command line

    esky2det datastyle=user ra=03h47m40.2s dec=24d21m54.62s outunit=raw
    

    gives the output

    # Instrument: EPN
    # Coord sytem of output is RAWXY (PIXCOORD1).
    # Source RA =  56.917500 deg.
    # Source dec =  24.365171 deg.
    #
    # rawX      rawY    ccd   On chip?
      32.05    188.69    8      T
    

  2. Example 2: if you want to display the numbers only, add withheader=`no' to the command line. In the case above, this would give

      32.05    188.69    8      T
    

    This style is suitable for batch running of esky2det from scripts.

  3. Example 3: in this example, the DETX/Y coordinate system is chosen and an uncertainty radius is supplied. The command line example is

    esky2det datastyle=user ra=03h46m25.3s dec=24d18m30.3s outunit=det
    witherrorradius=yes  errorradius=00d00m05.0s
    

    which gives the output

    # Instrument: EPN
    # Coord sytem of output is DETXY (CAMCOORD2 but in units of 0.05 arcsec).
    # Source RA =  56.605415 deg.
    # Source dec =  24.308416 deg.
    #
    # detX       detY       det err
    -15043.9    -2111.8       100.0
    

  4. Example 4: The same command, but with outunit set now back to `raw', gives

    # Instrument: EPN
    # Coord sytem of output is RAWXY (PIXCOORD1).
    # Source RA =  56.605415 deg.
    # Source dec =  24.308416 deg.
    #
    # rawX      rawY    ccd   On chip?      X err       Y err
      40.11    189.72   12      T       0.455E-01   0.455E-01
    

For the convenience of script authors, I give below the number fields for all four combinations of outunit and witherrorradius:

If outunit=`det', and the source is outside the field of view of the instrument, the task halts with an error. If outunit=`raw' and the source is not found to lie within the bounds of any CCD, a warning message is issued; however the task still prints a RAWX/Y position, this being the position of the source in the RAWX/Y coordinate system of the nearest CCD. In this case the value of the `On chip?' column is `F' rather than `T'.


Description Description FITS file position IO. Home Index

XMM-Newton SOC/SSC -- 2006-06-28