On resonance quantum limit for interference gravitational antenna

In quantum measurement theory, the sensitivity of a measuring instrument is bounded below by the standard quantum limit (SQL). The expression for SQL obtained by the authors for an exactly solvable problem on a gravitational-wave interference detector enables the estimation of the minimum metric curvature in a periodic gravitational wave in the resonance and nonresonance cases. The authors consider the dependence of SQL on the selection of an observable quantity and on the intensity of a laser beam for the exponential distribution of the number of photons.