Calibration of AGILE-GRID with in-flight data and Monte Carlo simulations

AGILE is a gamma/X-ray telescope which has been in orbit since 23 April 2007. The gamma-ray detector, AGILE-GRID, has observed Galactic and extragalactic sources, many of which were collected in the first AGILE Catalog. We present the calibration of the AGILE-GRID using in-flight data and updated Monte Carlo simulations, producing response matrices for the effective area, energy dispersion, and point spread dispersion as a function of pointing direction in instrument coordinates and energy. We performed Monte Carlo simulations in GEANT3 at different gamma-ray photon energies and incident angles, using Kalman filter-based photon reconstruction and on-board and on-ground filters. Long integrations of in-flight observations of the Vela, Crab and Geminga sources in broad and narrow energy bands were used to validate