Martin's update, 20 mar '12

Binary

See https://clover.pas.rochester.edu/trac/astrobear/blog/binaryBondi for images and movies.

  • In general, for times <~ 1orbit, the 40 AU runs form strongly tilted disks with angular momenta vectors which are
    • contained very close to the orbital plane
    • point at the winds incoming direction; ~10o from the primary's position.
  • This tilt seem independent of:
    • the soft radius
    • whether the gas initial condition is a light static ambient medium or the AGB wind
    • q, for I tried for q=m1/m2=1.5,2
    • the secondary's spin
  • The formation of this structure is ~4 times faster for rsoft=0 than for rsoft=2dx
  • I see a less pronounced tilt in a 11au run (see https://clover.pas.rochester.edu/trac/astrobear/blog/binaryBondi 20 mar '12)
  • The tilt doesn't happen in runs with:
    • a<~5au separation (as in M&M)
    • more resolution (because the 11-40au grids are larger) to see the Hill radii. I've not used more resolution yet, for these sims running times are rather large and wanted to see if I could get disks in sensible walltimes.
    • the 2 conditions above + vwind=20km/s
  • I do not fully understand why such a dramatic tilt in the 40au case, yet the wind velocity, the shear and the wind density near the secondary's position, are all higher in the 11au sims than in the 40au ones. Also, the No. of cells per rHill scales down with the size of the grid.
  • As reported by email, one of my 40au test produced a disk on the orbital plane, but for:
    • an initial AGB wind with a density perturbation (which are expected in AGB stars; i.e. early pulsations)
    • boundary inflow, which was not intended.

I found the tilt again once I removed both the boundary inflow and the wind density perturbation. I'd like to try the perturbation again (without the inflow).

Next steps:

  • 40 au runs with higher resolutions
  • Longer runs
  • these runs should take about 1.5-2 weeks to run, even with the sandwich grids I'm using which, BTW, are enough to resolve Hill radii. I've not seen significantly faster runs in bluegene so far. I suspect, however, based on previous tests, that the bluegene sims will stop due to the error reported in ticket 121.

CRL618, several new plots and movies at https://clover.pas.rochester.edu/trac/astrobear/blog/crl618Figures#comment-1

AGN jet truncation. Model 2 is running now, see https://clover.pas.rochester.edu/trac/astrobear/blog/agnJetTruncation

Magnetic tower. Waiting for comments from Eric, Pat, Sergey and Jerry. Will submit to ApJ next friday.

PN winds. I'm working on the referee's suggestions, see Figures 2,3 and 4 in http://www.pas.rochester.edu/~martinhe/PNpaper-mnras2.pdf

Color figures for the printed version?

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