Table 1: Best parameters for the AB Aurigae disk derived from $\chi ^2$ minimization in the UV plane.
Assumed distance D (pc) = 140

Lines $^{12}{\rm CO}$ J = 2 $\rightarrow$ 1   $\dag$ $^{13}{\rm CO}$ J = 2 $\rightarrow$ 1   $\ddag$ $^{13}{\rm CO}$ J = 1 $\rightarrow$ 0   $\ddag$ ${\rm C}^{18}{\rm O}$ J = 1 $\rightarrow$ 0   $\sharp$

Systemic velocity ${V}_{\rm LSR}$ (km s^-1) = 5.89 $\pm$ 0.01 5.84 $\pm$ 0.01 5.87 $\pm$ 0.03 5.84 $\pm$ 0.02

Orientation PA ( $^\circ$ ) = -27.5 $\pm$ 0.5 -31.3 $\pm$ 0.3 -30 $\pm$ 1 -29 $\pm$ 1

Inclination i ( $^\circ$ ) = 33 $\pm$ 1 42 $\pm$ 1 39 $\pm$ 2 36 $\pm$ 3

Inner radius $R_{\rm in}$ (AU) = 45 $\pm$ 3 72 $\pm$ 5 77 $\pm$ 5 67 $\pm$ 6

Outer radius $R_{\rm out}$ (AU) = 1050 $\pm$ 10 890 $\pm$ 10 1300 $\pm$ 100 600 $\pm$ 60

Turbulent linewidth $\Delta {v}$ (km s^-1) = 0.38 $\pm$ 0.02 0.22 $\pm$ 0.02 0.26 $\pm$ 0.02 0.18 $\pm$ 0.05

Molecular column density law:   $\Sigma(r) = \Sigma_{100} \left(\frac{r}{100~{\rm AU}}\right)^{-p}$

Column density

     at 100 AU $\Sigma_{100}$ (cm^-2) = ( $1.4 \times 10^{19}$ ) $2.3 \times 10^{17}$ $\pm$ $0.3 \times 10^{17}$ $3.2 \times 10^{17}$ $\pm$ $0.8 \times 10^{17}$ $9.5 \times 10^{16}$ $\pm$ $1.3 \times 10^{16}$

     exponent p = (2.5) 2.4 $\pm$ 0.1 2.5 $\pm$ 0.3 3 $\sharp$

Temperature law:    $T(r)~ = T_{100} \left(\frac{r}{100~{\rm AU}}\right)^{-q}$

Temperature

     at 100 AU T₁₀₀ (K) = 68 $\pm$ 1 38 $\pm$ 2 34 $\pm$ 2 20 $\pm$ 3

     exponent q= 0.77 $\pm$ 0.02 0.16 $\pm$ 0.03 0.10 $\pm$ 0.14 -0.6 $\pm$ 0.2

Velocity law:       ${V}(r) = {V}_{100} \left(\frac{r}{100~{\rm AU}}\right)^{-v}$

Velocity at 100 AU V₁₀₀ (km s^-1) = 3.06 $\pm$ 0.06 2.54 $\pm$ 0.03 2.73 $\pm$ 0.12 2.75 $\pm$ 0.13

Velocity exponent v = 0.82 $\pm$ 0.02 0.42 $\pm$ 0.01 0.37 $\pm$ 0.02 0.47 $\pm$ 0.04

Continuum results*

Dust:   $\kappa_\nu = \kappa_o\times\left(\frac{\nu} {10^{12}~{\rm Hz}}\right)^{\beta}$

Absorption law $\kappa_o$ (cm²/g) = (0.1)

Dust exponent $\beta$ = $1.4 \pm 0.2$

Surface density law: $\Sigma(r) = \Sigma_{100} \left(\frac{r}{100~{\rm AU}}\right)^{-p}$

Surface density $\Sigma_{100}$ (H₂ cm^-2) = $6.3 \times 10^{23}$ $\pm$ $0.8 \times 10^{23}$

     at 100 AU $\Sigma_{100}$ (g cm^-2) = 2.7 $\pm$ 0.3

     exponent p = 2.3 $\pm$ 0.2

Inner radius R_i (AU) = 115 $\pm$ 5

Outer radius R_d (AU) = 350 $\pm$ 30

Mass M_d ( ${M}_{\odot}$ ) = $1.6 \times 10^{-2}$ $\pm$ $0.2 \times 10^{-2}$

   $\ddag$ ) For the ¹³CO lines, the error bars are derived from the 1 $\sigma$
formal errors from the $\chi ^2$ fit. We checked that all parameters
(except of course V₁₀₀) are essentially independent of the
inclinations over the $25{-}45^\circ$ range (see Sect. 3.3).
   $\dag$ ) For ¹²CO, multiple minima exist. We have selected a solution
in which the scale height is determined from the ¹³CO results:
h₁₀₀ = 12 AU, h = -1.40. The error bars, when mentioned, represent
the typical (1 $\sigma$ ) variations of the parameters obtained when varying all
other ones. Numbers in parenthesis represent assumed (fixed) values.
   $\sharp)$ For the C¹⁸O, only p-q is actually constrained: $p-q = 3.6 \pm 0.2$ .
See text for details.
  * ) For the continuum data, the temperature was taken as 35 K at 100 AU
with an exponent of q=0.3. The surface densities and mass (and their errors)
are given for $\beta = 1.4$ . An additional 30% uncertainty should be added
for these quantities, because of the error on $\beta$ .

Source LaTeX | All tables | In the text

	1 Introduction
	2 Observations and results
	3 Results
	4 Discussion
	5 Origin of the disturbances
	6 Summary
	References