SPECIFIC ANGULAR MOMENTUM DISTRIBUTION FOR SOLAR ANALOGS AND TWINS: WHERE IS THE SUN MISSING HIS ANGULAR MOMENTUM?

It is well established that there is a breakdown in the curve of specific angular momentum as a function of mass for stars on the main sequence Ref. 5. Stars earlier than F5 and more massive than the sun, rotate rapidly over a large mass range. For spectral type F5 and later, including the Sun, much smaller rotational velocities are found. We revisit this question from a new sample to shed a light on the basis of a sample solar twins and analogs recently observed by interferometric measurements of stellar radius. Our results clearly show that, as the Sun, the solar twins present similar global behavior from their specific angular momentum. 18 Sco and HIP 100963 have a specific angular momentum one order higher than the solar value, and HIP 55459 and HIP 56948 have a specific angular momentum one order lower than the solar value.