CURRENT CONSTRAINTS ON STELLAR ROTATION AROUND THE ZERO-AGE MAIN SEQUENCE (ZAMS) CANNOT CONSTRAIN MODELS FOR ANGULAR MOMENTUM EVOLUTION. AS STARS CONTRACT ON THE PRE-MAIN SEQUENCE THEY SPIN UP; ONCE THEY REACH THE ZAMS THEY BEGIN TO SPIN DOWN DUE TO BRAKING BY MAGNETIZED WINDS. ONLY A HANDFUL OF ROTATION PERIODS HAVE BEEN MEASURED FOR SOLAR-TYPE STARS BETWEEN 20 MYR AND 100 MYR SO FAR. WE PROPOSE TO FILL THIS GAP BY MEASURING ROTATION PERIODS FROM TESS FULL FRAME IMAGES FOR ROUGHLY 60 SOLAR-MASS STARS IN SIX 30 TO 50 MYR-OLD OPEN CLUSTERS. WITH THESE DATA IN HAND WE WILL PLACE STRONG CONSTRAINTS ON ROTATIONAL EVOLUTION AROUND THE ZAMS DISCRIMINATE BETWEEN MODELS FOR DIFFERENT CORE-ENVELOPE COUPLING TIMESCALES AND INVESTIGATE THE DEPENDENCE OF ACTIVITY ON ROTATION IN YOUNG SOLAR-TYPE STARS.

Smithsonian Institution, Washington DC

Investigators