Radiation-sensitive composition, method for forming resist pattern, and radiation-sensitive acid generator

A radiation-sensitive composition comprising:

• a polymer comprising an acid-releasable group;
• and
• a compound represented by formula (1):
• wherein L1 represents a group comprising a (thio)acetal ring formed by replacing each of two methylene groups of a monocyclic saturated aliphatic hydrocarbon ring by a (thio)ether bond so that two oxygens, two sulfurs, or one oxygen and one sulfur are bonded to one and the same carbon, or represents a group represented by the following formula (L-2):
• wherein L2 represents a bridged alicyclic group having 7 or more carbon atoms;
• X3 represents a single bond, an oxygen atom, a sulfur atom, or —SO2—;
• d represents 1 or 2;
• and *3 represents a chemical bond to W1 or a carboxy group,
• W1 represents a single bond or a (b+1)-valent organic group having 1 to 40 carbon atoms;
• R1, R2, and R3 each independently represent a hydrogen atom, a hydrocarbon group having 1 to 10 carbon atoms, a fluorine atom, or a fluoroalkyl group;
• Rf represents a fluorine atom or a fluoroalkyl group;
• a represents an integer of 0 to 8;
• b represents an integer of 1 to 4;
• d represents 1 or 2;
• when L1 represents the group represented by the formula (L-2), d in the formula (1) and d in the formula (L-2) are the same values;
• when a represents 2 or more, a plurality of R1 are the same or different, and a plurality of R2 are the same or different;
• when d represents 2, a plurality of W1 are the same or different, and a plurality of b are the same or different;
• and M+ represents a monovalent cation.