[Mesa-users] Changing reaction rate issu in PPISN
mrenzo at flatironinstitute.org
Thu Jan 20 19:52:01 UTC 2022
Hi Vaishnav and Harshda,
I believe you want to set num_special_rate_factors=1 in your inlist.
The exact setup to reproduce Farmer et al. results is available on
and https://zenodo.org/record/3559859 (and I believe
successfully used these).
Regarding running PPISN at low-Z: I would look at how sharp the core
edges are in these models. Once wind-mass loss becomes too small, the
cores become sharper and it is hard for pulses to get through them (as I
found in models with no-winds at finite Z). If you really want low-Z
model an idea could be add some small extra mixing (D_mix = 1d-2 for
example) to smooth the edges a bit without messing up the stars too
much. N.B: I have not tested this myself.
Hope this helps!
On 1/20/22 2:17 PM, Vaishnav Rao via Mesa-users wrote:
> Dear MESA users,
> We have been playing around with the PPISN test suite for the past
> year in an attempt to understand and reproduce the black hole mass
> gap. We were facing difficulties in incorporating custom reaction
> rates for the C12-O16 reaction in our test suite.
> We have been attempting to reproduce the plots of the effect of CO
> reaction rates on the final BH mass as in Farmer et al., 2019
> <https://arxiv.org/abs/1910.12874> and Farmer et al., 2020
> <https://arxiv.org/abs/2006.06678> . Using the reaction rates from the
> files of the latter, we tried to run a modified test suite with
> recommended settings (which had already run for the default rates for
> us before). However, upon comparing the final BH masses for 0 sigma
> and -1 sigma rate tables, there was no major difference, even though
> there is an expected difference of 8M in the final BH masses. Clearly
> the lines
> special_rate_factor(1)=1.0d0 ! Used for linear scaling of rates
> which specify the path to the modified rate tables do not seem to be
> having any major effect on the simulations.
> Our simulations are for metallicities of 1d-3 (in accordance
> withFarmer et al., 2019 <https://arxiv.org/abs/1910.12874>). We chose
> this metallicity because our simulations for 1d-5 ( as inFarmer et
> al., 2020 <https://arxiv.org/abs/2006.06678>) faced multiple
> convergence issues (mostly ‘hydro_failed’ or too many
> retries). According to the other posts we saw on the MESA mailing list
> archives, many others too faced convergence issues of this sort for
> such low metallicities. We are not sure whether using the same rate
> tables for different metallicities is correct.
> Our inlist, run_star_extras, and rate tables (zip file) have been
> attached for reference. Any advice on solving this issue would be
> Software details:
> MESA version: r12778
> SDK version: March 25, 2020
> OS: Cluster, 64-bit Linux
> Thanking you in advance,
> Vaishnav V. Rao & Harshda Saxena
> Department of Physics
> Indian Institute of Technology Bombay
> mesa-users at lists.mesastar.org
Mathieu Renzo <https://users.flatironinstitute.org/~mrenzo/>
Flatiron Research Fellow
Center for Computational Astrophysics
-------------- next part --------------
An HTML attachment was scrubbed...
More information about the Mesa-users