The accretion of hydrogen-rich material onto carbon-oxygen white dwarfs ( CO WDs ) is crucial for understanding type Ia supernova ( SN Ia ) from the single-degenerate model , but this process has not been well understood due to the numerical difficulties in treating H and He flashes during the accretion .
For the CO WD masses from 0.5 to 1.378 { M } _ { \odot } and accretion rates in the range from 10 ^ { -8 } to 10 ^ { -5 } { M } _ { \odot } \mbox { yr } ^ { -1 } , we simulated the accretion of solar-composition material onto CO WDs using the state-of-the-art stellar evolution code of MESA .
For comparison with the steady-state models ( e.g Nomoto et al .
( 26 ) ) , we firstly ignored the contribution from nuclear burning to the luminosity when determining the Eddington accretion rate and found that the properties of H burning in our accreting CO WD models are similar to those from the steady-state models , except that the critical accretion rates at which the WDs turn into red giants or H-shell flashes occur on their surfaces are slightly higher than those from the steady-state models .
However , the super-Eddington wind is triggered at much lower accretion rates , than previously thought , when the contribution of nuclear burning to the total luminosity is included .
This super-Eddington wind naturally prevents the CO WDs with high accretion rates from becoming red giants , thus presenting an alternative to the optically thick wind proposed by ( 7 ) .
Furthermore , the super-Eddington wind works in low-metallicity environments , which may explain SNe Ia observed at high redshifts .