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Error Determination

The errors (neterr) in each channel as listed in the file are given by:

         neterr=sqrt (src_less_part_err**2 + bkgd_norm_err**2)
where src_less_part_err is the error on: the source counts less the source charged particle counts; and bkgd_norm_err is the error on: the background counts less the background charged particle count, normalized by the ratio of source area to background area, by the vignetting ratio of effective areas, and by any user-supplied factor.

The error on each count is estimated from the count on the assumption that it arises from a Poisson process (by default). The error on each sum or difference of counts is estimated as the sum in quadrature of the estimated errors on the constituent counts.

If a systematic error is applied (this is the default for the IPC: pkgpars.ein_ipc_syserr=``0.03'' and qpspec.syserr=``'') then


Parameter names are, as far as possible, identical to those in the file.