Superstrings on AdS_2 and Superconformal Matrix Quantum Mechanics

We construct a kappa-symmetric Green-Schwarz action for type IIA string theory on AdS_2. As a candidate holographic dual, we consider superconformal matrix quantum mechanics, given by the Marinari-Parisi model with vanishing or logarithmic superpotential. We derive that the super-eigenvalues form a consistent subsector, and that their dynamics reduces to that of the supersymmetric Calogero-Moser model. The classical string action and the matrix model both have an infinite set of conserved charges, that include an N=2 target space super-Virasoro symmetry. As a microscopic test of the duality, we reproduce the exact form of the Calogero interaction via a string worldsheet calculation.