CEE

Conferences

  • Will submit blurb for the upcoming LANL meeting (date still not finalized), as requested of all participants by the organizer, Chris Fryer.

Jet paper

  • Submitted to MNRAS and astro-ph by Amy

EOS paper

Meeting?

A meeting before the end of Feb seems like a good idea. Times?

Writing

Made progress on Intro and Methods sections

Status of runs

  • 277 and 282 are now running on Frontera
  • Run 283 was not running properly (slow and chombos huge) ⇒ resubmitted using old executable (Baowei) and old module settings

Summary:

  • Run 277: MESA EOS (completed up to frame 288 or 67 days on Frontera)
  • Run 282: Ideal gas gamma=5/3 EOS (completed up to frame 295 or 68 days on Frontera)
  • Run 283: MESA EOS with recombination energy removed from EOS tables (completed up to frame 218 or 50 days on Frontera)
  • Run 276: MESA EOS with maxlevel increased by 1 compared to Run 277 (for convergence study — completed up to frame 47 or 11 days on Frontera)
  • Run 28?: MESA EOS with maxlevel reduced by 1 compared to Run 277 (for convergence study — not yet started on Frontera)
  • Run 271: MESA EOS with 7 times higher ambient (to explore role of ambient) (completed up to frame 235 or 54 days and will not extend)
  • Run 143 (fiducial run of past papers): Ideal gas gamma=5/3 EOS with 7 times higher ambient (to explore role of ambient) (completed up to frame 173 or 40 days and will not extend)

New analysis

Energy terms

We can calculate the released recombination energy two ways:

  1. Using the Saha equation and tracers to see how the ionic state has changed, calculate the corresponding energy released, and integrate over all gas (see notes from last post),
  2. Assume an ideal gas (with mean particle mass mu and temperature T taken from the simulation) and integrate to get the total thermal energy and subtract this from the internal energy to get the recombination energy. The negative of the net change in the recombination energy is equal to the released recombination energy.

We want to show that these two methods give approximately the same number (at every time).

I was able to roughly show this for the 7x higher ambient density run 271. However, with the new run 277, the ambient is at a high temperature and contains a lot of recombination energy. Therefore, it becomes more important to exclude the ambient gas when calculating the recombination energy by method 2 above. This calculation is in progress.

There is one small caveat. The potential energy term involving self-gravity of the gas makes use of the potential Phi due to all the gas (excluding particles). We made changes to the code to recalculate Phi excluding the ambient in postprocessing. This is expected to reduce the magnitude of the gas self-gravity potential energy term by 1%. However, it reduces it by 30%, so there must be a bug.

Unbound mass

For the same reason, ideally we would recompute the unbound mass using the correct Phi that does not include the ambient, but this would make such a small difference it may not be worth it (could be mentioned in a footnote). Consider that the unbound mass is perhaps already underestimated because we are including self-gravity of unbound envelope gas, which is maybe too conservative (e.g. Prust+Chang 2019 exclude it).

Ionization and Recombination

Spatial dependence ​http://www.pas.rochester.edu/~lchamandy/CE_papers/EOS/eos_ion_277.pdf. To reduce the number of plots I am planning to plot all the tracers in one plot, but to avoid overlapping them by only showing the tracer with the highest density at that location. This should be sufficient to make the points we want to make. Overlapping leads to ambiguity because the order of overlapping affects the shades so one can no longer read off the density from the color bar, so best to avoid overlapping.

Next steps

  • Compare the two methods of computing the released recombination energy and check that they agree at all times
  • Combine tracer figures and make colors non-overlapping
  • Continue to extend Runs 277, 282 and 283
  • Make progress on paper write-up
  • Explore overlapping ionization species regions to get a sense of how important they might be (< 10% difference?)
  • Calculate total angular momentum and check angular momentum conservation

Comments

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