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Table 1 Reference values for different types of stars

From: On the origin of jets from disc-accreting magnetized stars

  Protostar CTTS Brown dwarf White dwarf Neutron star
M ( M ) 0.8 0.8 0.056 1 1.4
R 2 R 2 R 0.1 R 5,000 km 10 km
R 0 (cm) 2.81011 2.81011 1.41010 109 2106
v 0 (cm s−1) 1.95107 1.95107 1.6107 3.6108 9.7109
P 1.04 days 5.6 days 0.13 days 89 s 6.7 ms
P 0 1.04 days 1.04 days 0.05 days 17.2 s 1.3 ms
B (G) 3.0103 103 2103 106 109
B 0 (G) 37.5 12.5 25.0 1.2104 1.2107
ρ 0 (g cm−3) 3.710−12 4.110−13 1.410−12 1.210−9 1.710−6
n 0 (cm−3) 2.21012 2.41011 8.51011 71014 1018
M ˙ 0 ( M yr 1 ) 1.810−7 210−8 1.810−10 1.310−8 210−9
E ˙ 0 (erg s−1) 2.11033 2.41032 2.51030 5.71034 61036
L ˙ 0 (erg s−1) 3.11037 3.41036 1.71033 1.61035 1.21033
T d (K) 2,290 4,590 5,270 1.6106 1.1109
T c (K) 2.3106 4.6106 5.3106 8108 5.61011
  1. We choose the mass M, radius R , equatorial magnetic field B and the period P of the star and derive the other reference values. The reference mass M 0 is taken to be the mass M of the star. The reference radius is taken to be twice the radius of the star, R 0 =2 R . The surface magnetic field B is different for different types of stars. The reference velocity is v 0 = ( G M / R 0 ) 1 / 2 . The reference time-scale t 0 = R 0 / v 0 , and the reference angular velocity Ω 0 =1/ t 0 . We measure time in units of P 0 =2π t 0 (which is the Keplerian rotation period at r= R 0 ). In the plots we use the dimensionless time T=t/ P 0 . The reference magnetic field is B 0 = B ( R / R 0 ) 3 / μ ˜ , where μ ˜ is the dimensionless magnetic moment which has a numerical value of 10 in the simulations discussed here. The reference density is taken to be ρ 0 = B 0 2 / v 0 2 . The reference pressure is p 0 = B 0 2 . The reference temperature is T 0 = p 0 /R ρ 0 = v 0 2 /R, where is the gas constant. The reference accretion rate is M ˙ 0 = ρ 0 v 0 R 0 2 . The reference energy flux is E ˙ 0 = M ˙ 0 v 0 2 . The reference angular momentum flux is L ˙ 0 = M ˙ 0 v 0 R 0 . The poloidal magnetic field of the star (in the absence of external plasma) is an aligned dipole field.