Eddfac application for wind accretion in massive stars

[katiebreivik]

Camille Liotine noticed some anomalously enormous X-ray emission coming from some BH binaries that were arising from super-Eddington accretion rates. We had a closer look and realized that while the Eddington limit is considered carefully and correctly for Roche overflow stable mass transfer, but not for winds. Normally, you'd not expect winds to produce super-Eddington accretion rates, but in our treatment for LBV-like wind mass loss we set the mass loss rate to 1.5e-4 MSun/yr. Standard Bondi-Hoyle accretion assumptions lead to very super-Eddington accretion unless the wind accretion is also limited.

This PR adds new code to limit wind accretion to the Eddington limit specified by eddfac both when the stars are detached as well as during Roche overflow mass transfer. In the event that wind mass accretion is already super-Eddington during Roche overflow, the mass coming through the Roche potential is not accreted at all. Otherwise, the Eddington limit is applied such that the Roche overflow mass is limited by the Eddington limit minus the amount of mass accreted from winds.

[codecov[bot]]

Codecov Report

Merging #546 (2729af1) into develop (d1ef41d) will increase coverage by 1.13%. The diff coverage is 55.56%.

@@             Coverage Diff             @@
##           develop     #546      +/-   ##
===========================================
+ Coverage    87.01%   88.14%   +1.13%     
===========================================
  Files           40       40              
  Lines        25340    25353      +13     
===========================================
+ Hits         22049    22346     +297     
+ Misses        3291     3007     -284     

Impacted Files	Coverage Δ
cosmic/src/evolv2.f	57.72% <55.56%> (+0.04%)	:arrow_up:
cosmic/sample/initialcmctable.py	95.49% <0.00%> (+0.14%)	:arrow_up:
cosmic/sample/initialbinarytable.py	94.44% <0.00%> (+0.16%)	:arrow_up:
cosmic/evolve.py	89.58% <0.00%> (+34.17%)	:arrow_up:
cosmic/sample/sampler/multidim.py	86.49% <0.00%> (+68.92%)	:arrow_up:

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