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The suspension noise in interferometric gravitational wave detectors iscaused by losses at the top and the bottom attachments of each suspensionfiber. We use the Fluctuation-Dissipation theorem to argue that by carefulpositioning of the laser beam spot on the mirror face it is possible to reducethe contribution of the bottom attachment point to the suspension noise byseveral orders of magnitude. For example, for the initial and enhanced LIGOdesign parameters (i.e. mirror masses and sizes, and suspension fibers' lengthsand diameters) we predict a reduction of $\sim 100$ in the "bottom" spectraldensity throughout the band $35-100\hbox{Hz}$ of serious thermal noise. We thenpropose a readout scheme which suppresses the suspension noise contribution ofthe top attachment point. The idea is to monitor an averaged horizontaldisplacement of the fiber of length $ l$; this allows one to record thecontribution of the top attachment point to the suspension noise, and latersubtract it it from the interferometer readout. For enhanced LIGO this wouldallow a suppression factor about 100 in spectral density of suspension thermalnoise.Comment: a few misprints corrected; submitted to Classical and Quantum Gravit

How to reduce suspension thermal noise in LIGO without improving theQof the pendulum and violin modes