Double Inflation in Supergravity and the Large Scale Structure

Cosmological implication of a double inflation model with hybrid + new inflations in supergravity is studied. The hybrid inflation drives an inflaton for the new inflation close to the origin through supergravity effects and the new inflation naturally occurs. If the total e-fold number of the new inflation is smaller than $\sim 60$, both inflations produce cosmologically relevant density fluctuations. Both cluster abundances and galaxy distributions provide strong constraints on the parameters in the double inflation model with assuming $\Omega_0=1$ standard CDM scenario. The future satellite experiments to measure the angular power spectrum of CMB will make precise determination of model parameters possible.