[Mesa-users] Mass loss in conservative mass transfer

[Pulkit Ojha]

Hi Neev,

Taking a look at your inlists and run_binary_extras.f90 , there doesn't
seem to be any extra parameter responsible for mass loss. But, I would
suggest you to look at your "binary_controls.defaults" file in the defaults
folder, assuming you haven't checked it much since it hasn't been shared.
There may be a few controls related to wind mass transfer which can produce
some mass loss from the system.
May be, try to put " do_wind_mass_transfer_1 = .false.
   do_wind_mass_transfer_2 = .false. " , in your inlist_project and see if
it helps.

Cheers
Pulkit

On Tue, Sep 17, 2024 at 1:59 AM Neev Shah via Mesa-users <
mesa-users at lists.mesastar.org> wrote:

> Hi,
>
> I am trying to run fully conservative mass transfer using the template in
> $MESA_DIR/binary/work (mesa version mesa-24.08.1). I believe the winds are
> set to 0, and the mass transfer parameters are also set to 0. I have turned
> off the eddington limit to allow for conservative mass transfer
> (limit_retention_by_mdot_edd = .false.). Initially, I kept the secondary as
> a point particle (evolve_both_stars = .false.) and it led to some mass loss
> from the system during mass transfer (figures below where I can see that
> dm2/dt is smaller than dm1/dt during mass transfer) and I am not sure why
> that is happening.
>
> [image: image.png]
> [image: image.png]
>
> I checked that by evolving the secondary as well (evolve_both_stars =
> .true.), the mass loss disappears and the system is fully conservative
> (figures below). The only difference between the 2 runs was that I changed
> evolve_both_stars from .false. to .true.
>
> [image: image.png]
> [image: image.png]
>
> Is there any reason for why there is mass loss when treating the secondary
> as a point particle?
>
> I have attached my inlists in the tarball below. My system had a donor
> mass of 15, accretor mass of 10, and an initial orbital period of 20 days.
>
> Thank you!
>
> Best,
> Neev Shah (he/him)
> Astronomy PhD student
> Steward Observatory
> University of Arizona
> _______________________________________________
> mesa-users at lists.mesastar.org
> https://lists.mesastar.org/mailman/listinfo/mesa-users
>
>

-- 
Pulkit Ojha
Research Assistant,
Theoretical Physics Division,
Institute of Mathematical Sciences <https://www.imsc.res.in/>,
Chennai, INDIA
Graduated as Int. MSc. (Physics) from
National Institute of Science Education and Research
<https://www.niser.ac.in/>
Bhubaneswar, INDIA
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.mesastar.org/pipermail/mesa-users/attachments/20240917/f51c1ea3/attachment.htm>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image.png
Type: image/png
Size: 17803 bytes
Desc: not available
URL: <https://lists.mesastar.org/pipermail/mesa-users/attachments/20240917/f51c1ea3/attachment.png>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image.png
Type: image/png
Size: 26695 bytes
Desc: not available
URL: <https://lists.mesastar.org/pipermail/mesa-users/attachments/20240917/f51c1ea3/attachment-0001.png>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image.png
Type: image/png
Size: 17043 bytes
Desc: not available
URL: <https://lists.mesastar.org/pipermail/mesa-users/attachments/20240917/f51c1ea3/attachment-0002.png>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image.png
Type: image/png
Size: 24098 bytes
Desc: not available
URL: <https://lists.mesastar.org/pipermail/mesa-users/attachments/20240917/f51c1ea3/attachment-0003.png>