Analytical estimates of core optics stray light noise and design requirements for ground based gravitational wave detectors

Abstract

We present an analytical framework to translate detector sensitivity into stray light requirements for the core optics region of ground based gravitational wave interferometers. We derive analytical estimates for several relevant scattering regimes, extend the treatment to collections of planar baffles, and obtain an analogous requirement for deterministic ghost beams intercepted by beam dumps. The framework is intended to provide conservative design requirements before a complete optical layout is available. We apply it to Cosmic Explorer to show how these estimates can be used to derive requirements for next generation detectors. The resulting expressions provide a compact set of tools for stray light budgeting and early design studies in current and future gravitational wave detectors.