Resist composition, method for forming resist pattern, compound, and polymer compound

A resist composition which generates an acid upon light exposure and whose solubility in a developing solution is changed by an action of the acid, the resist composition comprising:

• a resin component (A1) whose solubility in a developing solution is changed by the action of the acid,
• wherein the resin component (A1) has a constitutional unit (a0) derived from a compound represented by General Formula (a0-m),
• wherein W represents a polymerizable group-containing group, RAr1 and RAr2 each independently represent an aromatic group which may have a substituent, RAr1-L11-represents RAr1—O—, RAr1—S—, RAr1—NH—, RAr1-Ak-, RAr1—C(═O)—O—, RAr1—C(═O)—NH—, RAr1—O—C(═O)—, RAr1—NH—C(═O)—, RAr1-Ak-O—, RAr1-Ak-NH—, RAr1—O—C(═O)-Ak-, or RAr1- when L11 represents a single bond), Ak represents an alkylene group or a fluorinated alkylene group, and the same applies hereinafter, RAr1-L12- represents RAr1-Ak-, RAr1—C(═O)—O-Ak-, RAr1—C(═O)—NH-Ak-, RAr1—O—C(═O)-Ak-, RAr1—NH—C(═O)-Ak-, RAr1—O—C(═O)—, or RAr1— when L12 represents a single bond, RAr1-L13- represents RAr1—O—, RAr1—S—, RAr1—NH—, RAr1-Ak-, RAr1—O-Ak-, or RAr1— when L13 represents a single bond, RAr2-L14- represents RAr2-Ak-, RAr2—C(═O)—O-Ak-, RAr2—C(═O)—NH-Ak-, RAr2—O—C(═O)-Ak-, RAr2—NH—C(═O)-Ak-, RAr2—O—C(═O)—, or RAr2— when L14 represents a single bond), RAr2-L15- represents RAr2—O—, RAr2—S—, RAr2—NH—, RAr2-Ak-, RAr2—O-Ak-, or RAr2— when L15 represents a single bond), q represents 0 or 1, R01 and R02 each independently represents an iodinated alkyl group, an iodine atom, or a hydrogen atom, j1 and j2 each independently represents an integer of 0 to 5, where in a case where q represents 0, R02 represents an iodinated alkyl group or an iodine atom, and j2 represents an integer of 1 to 5, in a case where q represents 1, the number of iodine atoms in R01 and R02 is 1 or more, k1 and k2 each independently represents 0 or 1, where in a case where q represents 0, k2 represents 1, and in a case where q represents 1, k1+k2 is 1, Mm+ represents an m-valent onium cation, and m represents an integer of 1 or greater.