In nonjury cases the judge shall, after conducting the presentence hearing as provided in § 23A-27A-2, designate, in writing, the aggravating circumstance or circumstances, if any, which he found beyond a reasonable doubt. Unless at least one of the statutory aggravating circumstances enumerated in § 23A-27A-1 is so found, the death penalty shall not be imposed.
SDCL 23A-27A-6