[mesa-users] Pre-MS to Wolf-Rayet Evolution Problem

[Frank Timmes]

dear irham,

please look at your plots and make as strong an effort 
as you can on your own to understand what is going on. 
for example, what stage of evolution is the core in? 
how does this stage of core evolution relate to motion, 
or lack of motion as the case may be, in an hr diagram?

i apologize for not having more time in this discussion board
to guide you towards a better grasp of your plots or 
standard stellar evolution. what i will say is your plots suggest 
(a) mesa appears to be working just fine and (b) core-collapse is imminent.

fxt





> On Oct 16, 2016, at 9:02 PM, Irham Taufik <irham.andika at gmail.com> wrote:
> 
> Dear all,
> 
> I attached a figure that shows evolutionary track followed by my star. As I mention before, the track is stuck at the phase that is marked by red circle and can not reach next stage. At that phase the timesteps of computation become small but I don't know why.
> 
> Frank Timmes, can you explain me more about "a very thin surface layer might be causing the small timesteps" ?
> 
> 
> Best regards,
> Irham
> 
> On 17 October 2016 at 01:29, Frank Timmes <fxt44 at mac.com> wrote:
> one reason for my question, as matteo noted, is the lack
> of a TPAGB phase for massive stars. in addition, the “WR phase”
> is usually taken to mean a stripping of the outer hydrogen envelope
> that exposes the products of core burning which have been transported
> to the outer layers (wn, wc, wo …)
> 
> my current suggestion is to do a more complete analysis of
> the evolution - how much mass has been lost, what do the
> abundance profiles look like, etc. i suspect, but do not know,
> that a very thin surface layer might be causing the small timesteps.
> 
> fxt
> 
> 
> 
> 
> 
> 
> > On Oct 16, 2016, at 8:34 AM, Irham Taufik <irham.andika at gmail.com> wrote:
> >
> > Dear Frank Times,
> >
> > I attached the evolutionary track of 32 Msun star that is taken from Geneva Stellar Database. Basically, I want to create similar evolutionary track using MESA with same input parameters as in Geneva model.
> >
> > However, my star stuck in the TPAGB phase (red oval) can not reach desired WR phase (green oval) because the computation is very slow. Is there something wrong with my inlist?
> >
> > Best regards,
> > Irham
> >
> > On Oct 16, 2016 10:09 PM, "Frank Timmes" <fxt44 at mac.com> wrote:
> > hi irham,
> >
> > it might be useful to know how “WR phase” and “TPAGB” are defined for a 32 msun model.
> >
> > fxt
> >
> >
> >
> >
> > > On Oct 16, 2016, at 5:05 AM, Irham Taufik <irham.andika at gmail.com> wrote:
> > >
> > > Dear all,
> > >
> > > Currently I use MESA to create evolution model of 32 M_sun star from pre-MS to Wolf-Rayet phase. However, it seems the program only works until TPAGB and cannot reach WR phase. I attached my inlist file in this email. Is there something wrong with my input parameters?
> > >
> > > Best regards,
> > > Irham
> > >
> > >
> > >
> > > --
> > > Irham Taufik Andika
> > > Astronomy Study Program
> > > Bandung Institute of Technology, Indonesia
> >
> > <figure_1.png>
> 
> 
> 
> 
> -- 
> Irham Taufik Andika
> Astronomy Study Program
> Bandung Institute of Technology, Indonesia
> <wr_mod1.png>