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Last modified: December 2013

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AHELP for CIAO 4.9 Sherpa v1


Context: utilities


Calculate the k correction for a spectral model.


calc_kcorr(z, obslo, obshi, [restlo, resthi, id, bkg_id] )


The calc_kcorr command calculates the k correction for a spectral model, redshift, and energy range for a source or background dataset. The energy range is taken to be obslo <= energy < obshi .

  • z - the redshift can be a scalar or a 1-D array; the return value matches that of z. If it is an array, the k correction is evaluated for each redshift in the array.
  • obslo - observed-frame lower energy limit (keV)
  • obshi - observed-frame upper energy limit (keV)
  • restlo - rest-frame lower energy limit (keV); default=obslo
  • resthi - rest-frame upper energy energy (keV); default=obshi
  • id - the id of the dataset to use; if not given, uses the default dataset id (id=1 by default, see "ahelp get_default_id")
  • bkg_id - the id of the background, if calculating the kcorr for the background; default is the first background associated with the id

Example 1

sherpa> calc_kcorr(0.5, 0.5, 2)

Calculate the k correction for a redshift of 0.5 over the energy range 0.5 to 2 keV.

Example 2

sherpa> calc_kcorr(0.5, 0.5, 2, 2, 10, bkg_id=2)

Calculate the k correction for the background dataset bkg_id=2 for a redshift of 0.5 over the energy range 0.5 to 2 keV with rest-frame energy limits of 2 to 10 keV.


See the bugs pages on the Sherpa website for an up-to-date listing of known bugs.

See Also

copy_data, dataspace1d, dataspace2d, datastack, delete_data, fake, get_axes, get_bkg_plot, get_counts, get_data, get_data_plot, get_dep, get_dims, get_error, get_quality, get_specresp, get_staterror, get_syserror, group, load_ascii, load_data, load_grouping, load_quality, set_data, set_quality, ungroup, unpack_ascii, unpack_data
get_filter, load_filter, set_filter
get_default_id, list_data_ids, list_response_ids
plot_data, set_xlinear, set_xlog, set_ylinear, set_ylog
save_error, save_filter, save_grouping, save_quality, save_staterror, save_syserror
calc_data_sum, calc_data_sum2d, calc_ftest, calc_mlr, calc_model_sum2d, calc_source_sum2d, get_rate
contour, contour_data, contour_ratio, get_ratio, get_resid, histogram1d, histogram2d, image_data, rebin

Last modified: December 2013
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