DET-SPEC:  Specify detector noise model.

The det-spec program is used to specify the parameters of the detector
noise model.

Usage:

    det-spec log-file low-width[:high-width] [ low-df[:[high-df]] ]

or:

    det-spec log-file

The first form above appends the detector specification to the log
file named (which must already exist, see src-spec.doc).  The second
form displays the detector specification in the log file named.

The noise in detector measurements has either a Gaussian distribution
or a t distribution.  The log of the width parameter of the noise
(standard deviation for Gaussian noise) has a prior that is uniform
between log(low-width) and log(high-width).  If high-width is omitted,
it is assumed to be equal to low-width, in which case the width is
fixed.  If there is no df specification after the width prior, the
noise is Gaussian.  Otherwise, the noise has a t distribution with the
prior for the reciprocal of the df parameter being uniform between
1/high-df and 1/low-df.  If only low-df is specified, with no colon,
high-df is assumed to be equal to low-df, so df is fixed.  If a colon
is present but not high-df, high-df is assumed to be infinite (ie,
1/high-df is zero).

            Copyright (c) 2007 by Radford M. Neal