The impact of non-ideal magnetohydrodynamics on binary star formation (Dataset)
README (1.117Kb) pdata_altB1.zip (20.59Gb) pdata_altB2.zip (24.56Gb) pdata_altB3.zip (28.69Gb) pdata_altB4.zip (16.63Gb) pdata_fid1.zip (27.91Gb) pdata_fid2.zip (36.44Gb) pdata_fid3.zip (24.66Gb) pdata_fid4.zip (16.63Gb) pdata_fid5.zip (20.90Gb) pdata_fid6.zip (28.60Gb) pdata_fid7.zip (24.84Gb) pdata_fid8.zip (22.69Gb) pdata_nicil.zip (17.19Gb) pdata_sub.zip (23.28Gb) sdata_cslow1.zip (15.24Gb) sdata_cslow2.zip (13.55Gb) sdata_cslow3.zip (18.03Gb) sdata_cslower1.zip (21.88Gb) sdata_cslower2.zip (21.11Gb) sdata_cslowest1.zip (15.23Gb) sdata_cslowest2.zip (15.22Gb) sdata_cslowest3.zip (18.00Gb) sdata_slow1.zip (15.25Gb) sdata_slow2.zip (13.06Gb) sdata_slow3.zip (15.73Gb) sdata_zeta.zip (12.91Gb)Show MoreShow Less
Price, Daniel J
Monthly Notices of the Royal Astronomical Society
University of Exeter
We investigate the effect of non-ideal magnetohydrodynamics (MHD) on the formation of binary stars using a suite of three-dimensional smoothed particle magnetohydrodynamics simulations of the gravitational collapse of 1 M⊙, rotating, perturbed molecular-cloud cores. Alongside the role of Ohmic resistivity, ambipolar diffusion and the Hall effect, we also examine the effects of magnetic field strength, orientation and amplitude of the density per- turbation. When modelling sub-critical cores, ideal MHD models do not collapse whereas non-ideal MHD models collapse to form single protostars. In supercritical ideal MHD models, increasing the magnetic field strength or decreasing the initial-density perturbation amplitude decreases the initial binary separation. Strong magnetic fields initially perpendicular to the rotation axis suppress the formation of binaries and yield discs with magnetic fields ∼10 times stronger than if the magnetic field was initially aligned with the rotation axis. When non-ideal MHD is included, the resulting discs are larger and more massive, and the binary forms on a wider orbit. Small differences in the supercritical cores caused by non-ideal MHD effects are amplified by the binary interaction near periastron. Overall, the non-ideal effects have only a small impact on binary formation and early evolution, with the initial conditions playing the dominant role.
This is the data that was used in Wurster, Price & Bate (2017). This dataset was created using the SPHMD code Phantom using the NICIL library to calculate the non-ideal MHD coefficients. The data and important files have been uploaded; the data files can be read with either Phantom, or with the graphics programme Splash. The filenames represent the original path and the simulation. The first component of the name is pdata: primary data sdata: supplementary data the second components are pdata: fid: fiducial runs altB: fiducial non-ideal MHD runs, using +B_z & -B_x nicil: runs using the updated version of NICIL sub: runs using mu_0 < 1 sdata: zeta: runs with a cosmic ray ionisation rate 10 lower than fiducial slow: initial angular momentum and sound speed match Wurster, Price & Bate (2016) cslow: Omega_0 = 3.54e-13 s^-1; all other parameters match the fiducial models cslower: Omega_0 = 7.08e-13 s^-1; all other parameters match the fiducial models cslowest: Omega_0 = 1.77e-13 s^-1; all other parameters match the fiducial models and the third component is the simualtion name (which may unfortunately be a little cryptic). Typically, the model name has the form ABCD, where A=i for ideal, A=n for non-ideal B=f for mu0=5, B=t for mu0=10 C=t for A0=0.2, C=o for A0=0.1, C=h for A0=0.05 D=z for -Bz, D=x for +Bx, D=zp for +Bz, D=xn for -Bx
MNRAS, 466:1788-1804, April 2017