Microscopic study of pionic atoms and methods of production

We have constructed a theoretical optical potential for pionic atoms and low energy pions based on the first and second order terms of a many body expansion on the number of ph excitations. The new density dependence of the potential produces notoriously improved results in the problem of the anomalies. On the other hand we have separated the different contributions to the imaginary part of the potential and relate them to the different reaction channels, quasielastic and absorption. The agreement with the data for different channels, energies and nuclei is rather good with some isolated discrepancies. With this potential we have also investigated the deeply bound pionic states in heavy nuclei so far unobserved and we propose a new direct reaction to create these states. (authors)