Amplitudes of solar-like oscillations in red giants: Departures from the quasi-adiabatic approximation

Amplitudes of solar-like oscillations in red giants: Departures from the quasi-adiabatic approximation

Blog Article

CoRoT and Kepler measurements reveal us that the amplitudes of solar-like oscillations detected in red giant stars scale from stars to stars in a characteristic way.This observed scaling relation is not yet fully understood but constitutes potentially a powerful toe ring diagnostic about mode physics.Quasi-adiabatic theoretical scaling relations in terms of mode amplitudes result in systematic and large differences with the measurements performed for red giant stars.The use of a non-adiabatic intensity-velocity relation derived from a non-adiabatic pulsation code significantly reduces the discrepancy with the CoRoT measurements.

The origin of the remaining difference is Silver Solder still unknown.Departure from adiabatic eigenfunction is a very likely explanation that is investigated in the present work using a 3D hydrodynamical model of the surface layers of a representative red giant star.