Intramolecular coupling of diradicals of different sizes (1,4-, 1,5-, 1,6-, 1,7-, 1,8-diradicals, as well as very remote diradicals) formed through intramolecular hydrogen abstraction by an excited ketone, yielding cyclic alcohols of different sizes.
Source:
PAC, 2007, 79, 293. 'Glossary of terms used in photochemistry, 3rd edition (IUPAC Recommendations 2006)' on page 441 (https://doi.org/10.1351/pac200779030293)