[ Identification | Description | Input parameters | Output parameters | Links ]
Phonon_simple
ComponentSingle-cylinder shape. Absorption included. No multiple scattering. No incoherent scattering emitted. No attenuation from coherent scattering. No Bragg scattering. fcc crystal n.n. interactions only One phonon branch only -> phonon polarization not accounted for. Bravais lattice only. (i.e. just one atom per unit cell) Algorithm: 0. Always perform the scattering if possible (otherwise ABSORB) 1. Choose direction within a focusing solid angle 2. Calculate the zeros of (E_i-E_f-hbar omega(kappa)) as a function of k_f 3. Choose one value of k_f (always at least one is possible!) 4. Perform the correct weight transformation
Name | Unit | Description | Default |
---|---|---|---|
radius_o | m | Outer radius of sample in (x,z) plane | |
h | m | Height of sample in y direction | |
focus_r | m | Radius of sphere containing target. | 0 |
focus_xw | m | horiz. dimension of a rectangular area | 0 |
focus_yh | m | vert.. dimension of a rectangular area | 0 |
focus_aw | deg | horiz. angular dimension of a rectangular area | 0 |
focus_ah | deg | vert.. angular dimension of a rectangular area | 0 |
sigma_a | barns | Absorption cross section at 2200 m/s per atom | |
sigma_i | barns | Incoherent scattering cross section per atom | |
a | AA | Lattice constant (fcc) | |
b | fm | Scattering length | |
M | a.u. | Atomic mass | |
c | meV/AA^{-1} | Velocity of sound | |
DW | 1 | Debye-Waller factor | |
T | K | Temperature | |
target_x | 0 | ||
target_y | m | position of target to focus at (m) | 0 |
target_z | 0 | ||
int target_index | 0 |
Name | Unit | Description | Default |
---|---|---|---|
V_rho | AA^-3 | Atomic density | |
V_my_s | m^-1 | Attenuation factor due to incoherent scattering | |
V_my_a | m^-1 | Attenuation factor due to absorbtion |
Phonon_simple.comp
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[ Identification | Description | Input parameters | Output parameters | Links ]
Generated automatically by McDoc, Peter Willendrup <peter.willendrup@risoe.dk> / Feb 28 2006