The usage of S/N in this context is not the same as in standard photometry. ``Noise'' has the same meaning, but here ``signal'' refers to the intrinsic strength of the modulation. If a star is measured to 2 accuracy and has at 10 modulation (0.2 magnitudes peak to peak), the S/N is 5.

Scott J. Wolk
Thu Dec 5 11:30:29 EST 1996