This allows pipelines to provide sub-threshold observations when the
signals in some detectors are too faint to produce triggers.
If the SNR time series are missing, then BAYESTAR will print a warning
and synthesize fake SNR time series from the autocorrelation sequences
of the whitened templates.
Original: 3a135d1cf4bfee4bb566e9972d0e7009a7a7b161