Dense Spherical Wind followed by AGB wind

I used 400 K isothermal gas temperature. In ​The dust disk and companion of the nearby AGB star L2 Puppis, they infer that the inner rim of the circumbinary disk is about 1000 K - 1200 K at 6 AU away from the AGB star. So 400 K is approximately the temperature at 24 AU - 40 AU. Since my simulation extend to 80 AU, I think 400 K is somewhat reasonable.

The gas is assumed 100% hydrogen atom. The wind is all spherical this time. The slow dense shell bear initial velocity of 16 km/s and mass loss rate of 5E-5 SM/yr while the AGB wind has initial velocity of 32 km/s and mass loss rate of 1E-7 SM/yr. The dense shell ejection last for 11.6 yrs and the AGB wind last for the rest of time so the total mass loss in this simulation is approximately 6.5E-4 SM. In the L2 Pup paper, the author estimated the dust weigh 1E-7 SM, if the gas dust mass ratio is 100, it implies that the mass of the disk is about 1E-5 SM. Usually, most of ejected material will leave the system and only a fraction stay in the circumbinary disk, I hope this fraction is 10%.

There is no dust and radiation transfer in my simulation so this initial velocity compensate some absence of the accelerate mechanism.

The AGB star is 1 SM and has radiative pressure on gas (I know the physics is much more complicate, e.g. radiative pressure on dust and dust and gas momentum coupling). The secondary is a compact accreting object which is different from the paper. I adopt the accreting object to make a hole in the center of the circumbinary disk, as I can keep removing gas from the disk. In reality, high temperature near the star can expel gas and create this hole. So temperature gradient is needed if we want to see a self consistent hole in the center.

Isothermal Temperature: 400 K

Primary mass: 1 SM with alpha=0.134 (behave like a 0.134 SM star to gas)

Secondary mass: 0.5 SM

Escape velocity to the primary star: 14.7 km/s

Separation: 4 AU

AGB wind: 32 km/s

Dense shell: 16 km/s

Wind ejection radius: 1 AU

Dense shell ejection duration: 11.6 yrs

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