Two-Loop Approximation in the Coulomb Blockade Problem

We study Coulomb blockade (CB) oscillations in the thermodynamics of a metallic grain which is connnected to a lead by a tunneling contact with a large conductance $g_0$ in a wide temperature range, $E_C g_0^{7/2} e^{-g_0 /2} T E_C g_0^{7/2} e^{- g_0 /2}$ the oscillation amplitude weakly depends on temperature we estimate the magnitude of CB oscillations in the ground state energy as $E_C g_0^{7/2} e^{-g_0 /2}$.