Benchmark Test Nr. 3
NOTE: THIS PAGE IS STILL UNDER CONSTRUCTION
The results found here are not the final ones yet!!!
So view this page as a concept of how it will look. |
The test described here is very similar to test 2. For detailed explanation see
that page. The only difference here is the temperature (and mass)
of the star.
| R_star | = | 2 *
R_sun | (Radius of the central star) |
| M_star | = |
0.5 *
M_sun | (Mass of the central star) |
| T_star | = |
3000
Kelvin | (Temperature of the central star) |
| R_in | = | 1 AU |
(Inner radius of disk annulus) |
| R_out | = | 1.01 AU |
(Outer radius of disk annulus) |
| beta | = | 0.05 |
(Grazing angle of incident radiation) |
| starvisfrac | = | 0.5 |
(Fraction of stellar surface visible from disk surface) |
| tau_tot | = | 1E+04 |
(Vertical 550 nm optical depth from z=-inf to z=+inf) |
| H_p | = | 0.1 AU |
(Pressure scale height of the disk) |
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The boldface font entries in the above table show which parameters
are different from test 1.
The spectrum of the star is assumed to be a perfect blackbody with the
temperature given above. The parameter "starvisfrac=0.5" means that it is
assumed that the disk somehow extends down to the stellar surface (although
we model here only this tiny annulus), so that
it obscures half of the stellar surface, i.e. the surface on the sky of an
observer standing on the surface of disk. Effectively this means that only
half of the usual stellar flux reaches the disk.
The opacity table to use for this test setup has
been computed by E. Kruegel, and is the opacity per gram
gas+dust for silicate dust. A plot of the
opacity table can be found here.
If everything goes alright, the outcoming flux of the annulus (which equals
the incoming flux) from one side of the disk is:
Flux_out = 9.96E+03 erg / cm^2 / s
which is the flux at the disk's surface (i.e. not the observed flux at
1 pc).
Objective:
The objective is to compute the temperature as a function of vertical
optical depth tau (at 550 nm). The tau coordinate is measured
from above (i.e. from vertical height Z=infinity downwards). The
vertical density structure is irrelevant for this problem, so that is why we
specify everything in terms of tau. Once the temperature structure is
found, the spectrum (spectral energy distribution) of the annulus should
be computed for an inclination incl = 0 deg (i.e. face-on) and a
distance of d = 1 parsec. The spectrum should include only the
annulus, i.e. not the star.
We would be very grateful if you submit your results to us via Email. You would then
do us a great favor if you submit your results in the following format, although we do not insist on this.
Remarks:
The parameters M_star and H_p are non-essential parameters.
But the value of H_p can be used to convert tau_tot into
the vertical coordinate z (height above the midplane), if one wishes
to use format type 1 for the submission. The
Density profile is then defined to be a Gaussian:
rho = Sigma exp(-0.5*z^2/H_p^2) / sqrt(2 pi) H_p.
Results from previous authors:
The results from previous authors are shown in the
results page. If you are an active participant
in the test, please do not view this page before having your own independent
results.
dullemon@mpa-garching.mpg.de
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