EDP Sciences logo
Subscriber Authentication Point
Search
Menu
Home All issues Volume 555 (July 2013) A&A, 555 (2013) A146 Full HTML
Free Access

Table 2

Properties of the Fomalhaut exozodiacal disk derived from the fit to the data.

Properties Hot ring Warm belt
Approach 1 Approach 2 Approach 1 Approach 2
Density peak r0 [AU] 0.09* (0.231) 0.09* (0.231) 1.59 2.52
[1.62, 2.43] [1.54, 2.15]
Inner density slope αin + 10* + 10* + 10* +3
[+2.99, +7.52]
Outer density slope αout −6* −6* –1.0 −1.5*
[–3.62, –0.60]
Mass up to 1 mm [M⊕] 2.5 × 10-10 2.6 × 10-10 2.86 × 10-6 1.87 × 10-6
[6.12 × 10-7,9.53 × 10-5] [1.14 × 10-6,7.81 × 10-5]
Maximum surface density [cm-2] 7.24 × 1011 7.46 × 1011 110 66.6
Maximum V-band optical depth τ⊥3 2.2 × 10-3 2.3 × 10-3 9.8 × 10-5 1.2 × 10-4
Fractional luminosity LD/L⋆ 5.89 × 10-3 5.71 × 10-3 5.04 × 10-4 6.09 × 10-4
Composition C C Si+C Si+C
Minimum grain size [μm] 0.01 0.01 3.51 2.31
[1.37, 56.1] [0.99, 57.2]
Grain size slope –6 –6 –4.8 –4.06
[–6.0, –3.8] [–6.0, –3.7]
Typical temperatures [K]2 [2000, 2200] [2000, 2200] [403, 464] [326, 364]
χ2 (d.o.f. = 30) – – 46.9 47.9

Notes.Approach 1 labels the model with free outer slope, approach 2 that with free inner slope. Numbers in bold are the parameters of the smallest χ2 fits, while the intervals give the 1σ confidence intervals from the Bayesian analysis. The

(*)

exponent marks the fixed parameters.

(1)

Approximate density peak position of the smallest grains (they vanish below that distance).

(2)

Give range of temperatures at r0 from the smallest to 1 mm grains. For the hot ring, the temperature of the smallest grains is given at their sublimation distance.

(3)

The optical depth is directly proportional to the dust mass and therefore constitute another definition to this free parameter (given in V-band by convention).

Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.

Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.

Initial download of the metrics may take a while.