Published November 11, 2025 | Version v2

Supplementary videos for the paper titled: Understanding the Drag Torque in Common Envelope Evolution

  • 1. ROR icon National Institute of Science Education and Research
  • 2. University of Rochester

Description

Supporting Materials for the paper titled, "Understanding the Drag Torque in Common Envelope Evolution", written by the authors listed in creators. The movies show temporal evolution of several physical quantities (listed below) of a common envelope evolution with an AGB star as primary and a companion of equal mass (0.53 solar mass). The softening radii of AGB core (left) and companion (right) are shown in black circles (yellow, in the torque_density movies). The files with "units_r_over_a" in their names are in r/separation units, while the files with "units_r_sun" are in solar radii units. Here are the quantities shown in the movies:

  1. Density: The movies starting with "density" show the pseudocolor plot of density in the orbital plane, with the thick white contour showing density= critical density= 0.006 times maximum density in each frame. The thin grey contours show density = 4 * critical density, 2 * critical density, 0.5 * critical density and 0.25 * critical density.
  2. Local Mach number of perturbers: The movies starting with "Mach_p" show the local Mach numbers of the perturbers (azimuthal component of velocity in particle CM frame divided by local sound speed), plotted between 0 and 2 in blue-red colors. The white region shows the transition from subsonic to supersonic (i.e. Mach= 1). The black contour shows density= critical density.
  3. Difference over sum of the perturber and gas angular velocity: The movies starting with "Omega_diff_over_sum" show the difference over sum of the angular velocities of perturber and gas. We use the average angular velocity of AGB core and companion for perturber angular velocity. The region is mostly red, showing perturber angular velocity dominating the gas angular velocity, while the pinch of blue at the center is probably due to turbulence. The white region near perturbers suggest that the gas is roughly in corotation in the region.
  4. Torque Density: The files starting with "torqure_density" show the torque density on both the particles. The black and white contours respectively show the negatively and positively contributing regions to the drag. The highest contour levels near the particles are +- 10^12 dyn cm^-2, and contours are also plotted for , +- 10^11 dyn cm^-2, +- 10^10 dyn cm^-2, and so on.

Files

density_units_r_over_a_all_frames_fps_10.gif

Files (408.2 MB)

Name Size
md5:736ac30a45cd158b9f5ad02cb5869496
42.9 MB Preview Download
md5:4102cd57dbaea152d8e59a145ccb3d4a
45.6 MB Preview Download
md5:63a2e7bfae878d221719dbeea903c03e
41.7 MB Preview Download
md5:0372f59adfcaa7ae9efdbe416a2bf0da
44.3 MB Preview Download
md5:fb1ef10518ebb3f530dc058fda2611c7
44.3 MB Preview Download
md5:62cbbc36694fa0f4422d15c3975f5148
46.9 MB Preview Download
md5:886add0e76d306a2b3ea84a7553637a3
70.3 MB Preview Download
md5:6440d4a10d9b3c9c8c9998639b61baa4
72.3 MB Preview Download