[Mesa-users] stellar wind velocity

[Saul A Rappaport]

Hi Jiri:

To reiterate, I’m simply trying to understand why, when a massive
star (5-20 Msun) reaches the giant branch, the stellar wind abruptly
drops from 50 km/sec to 10 m/sec.


From the content of the $MESA_DIR/star/defaults/history_columns.list file I would guess that what you get in v_wind_Km_per_s is the wind speed in the photosphere (determined from the mass-loss rate and photospheric density) and not the terminal wind speed. I would say that 10 m/sec is a perfectly reasonable value, while 50 km/sec could be too high and perhaps could be caused by a poor resolution of the photosphere, as Frank mentioned.

Many thanks for getting back to me on this.  I believe I understand what you are saying.

A final question would be the following.  If I’m interested in the terminal wind speed is it safe to simply ignore the speed given by v_wind_Km_per_s?


Saul
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