Optical excitation processes: general discussion. (25th August 2022) - Appleby, Martin; Barlow, Kyle; Basini, Martina; Benfatto, Lara; Boeije, Yorrick; Burnett, Andrew; Chen, Lin X.; Collet, Eric; Dürr, Hermann A.; Fleming, Graham; Girija, Aswathy V.; Hassan, Mohammed Th.; et al.