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Mass loss by red giants is an important process to understand the finalstages of stellar evolution and the chemical enrichment of the interstellarmedium. Mass-loss rates are thought to be controlled by pulsation-enhanceddust-driven outflows. Here we investigate the relationships between mass loss,pulsations, and radiation, using 3213 luminous Kepler red giants and 135000ASAS-SN semiregulars and Miras. Mass-loss rates are traced by infrared coloursusing 2MASS and WISE and by observed-to-model WISE fluxes, and are alsoestimated using dust mass-loss rates from literature assuming a typicalgas-to-dust mass ratio of 400. To specify the pulsations, we extract the periodand height of the highest peak in the power spectrum of oscillation. Absolutemagnitudes are obtained from the 2MASS Ks band and the Gaia DR2 parallaxes. Ourresults follow. (i) Substantial mass loss sets in at pulsation periods above~60 and ~100 days, corresponding to Asymptotic-Giant-Branch stars at the baseof the period-luminosity sequences C' and C. (ii) The mass-loss rate starts torapidly increase in semiregulars for which the luminosity is just above theRed-Giant-Branch tip and gradually plateaus to a level similar to that ofMiras. (iii) The mass-loss rates in Miras do not depend on luminosity,consistent with pulsation-enhanced dust-driven winds. (iv) The accumulated massloss on the Red Giant Branch consistent with asteroseismic predictions reducesthe masses of red-clump stars by 6.3%, less than the typical uncertainty ontheir asteroseismic masses. Thus mass loss is currently not a limitation ofstellar age estimates for galactic archaeology studies.

Asteroseismology of luminous red giants with Kepler. II. Dependence of mass loss on pulsations and radiation