Determination of ion recombination and polarity effects for the PTW Advanced Markus ionization chamber in synchrotron based scanning and collimated proton beams for ocular treatment. (December 2021) - Maestri, D.; Mirandola, A.; Magro, G.; Mastella, E.; Molinelli, S.; Rossi, E.; Russo, S.; Vai, A.; Ciocca, M.