Alternative Methods for Creating a Sodium Guidestar

Adaptive Optics allow ground-based astronomical observatories to overcome atmospheric distortion limited observation by using natural and artificial guide stars to measure the distortion. Sodium-layer guide stars provide near all-sky coverage for high resolution astronomy. Over the last 20 years, Optically Pumped Semiconductor Laser (OPSL), also referred to as Vertically Extended Cavity Surface Emitting Laser (VECSEL), technology has matured greatly realizing increases in power, reliability and wavelength coverage. Aret Associates and MIT Lincoln Laboratories (MIT-LL) propose development and demonstration of a high power semiconductor laser for Laser Guide Star (LGS) Adaptive Optics (AO) applications in Astronomy and Space Situational Awareness. Phase I will prove feasibility of the OPSL to meet the demanding performance challenges of LGS applications. Phase II will produce a LGS system suitable for deployment in an observatory. The Aret-MIT-LL collaboration constitutes a strong team. Aret a small, innovative R&D company with a proven track record in laser and instrument development for remote sensing applications has demonstrated single frequency OPSLs at the 589nm sodium resonance as well as other wavelengths. MIT LL, with proven OPSL materials growth and test capabilities is uniquely positioned to design, grow, process and characterize semiconductor gain mirrors to support the proposed development.