This module simulates a system which was called "Drabkin resonator".
The main field is a periodical magnetic field with permanent amplitude or
with some amplitude distribution. The amplitude distribution should has
a gauss or sinus law. This is gives a possibilities to improve the peak of
neutrons, which was flipped.
The
permanent magnetic field should be added to the periodic magnetic field.
This field must be situated in the perpendicular plane relativly the periodical
magnetic field.
Such field is calling "guide magnetic field". If we apply these two fields, we
must got a flipper, which is working in the narrow wavelength range. The full
width on the half height is depending from number of periods of the periodical magnetic
field. Also let me remind, incoming neutron beam should contain a some range of
wavelength. No monohromator should be installed before resonator!
The random magnetic field can be added also.
The axis OX has the direction of neutron flight.
The spin
precessions are treated classically i.e. this module only rotates the spin
vectors belonging to trajectories which pass through the rectangular geometry.
No attenuation is considered during the flight.
Module parameters:
| Parameter Unit |
Description | Command option |
| dimensions of field volume X,Y,Z [cm] |
Dimension of the common precession volume X,Y,Z | -X, -Y, -V |
| position main X,Y,Z [cm] |
Center position of the field volume. | -k, -l, -m |
| output X,Y,Z [cm] |
Position of the output frame (in the input frame). | -p, -r, -s |
| Number of domains in the X direction | Number of domains in the X direction (flight direction) | -C |
| Number of domains in the Y direction | Number of domains in the Y direction | -D |
| Number of domains in the Z direction | Number of domains in the Z direction | -E |
| Periodical field parallel to the axis | Periodical field is parallelling to the axis OX, OY or OZ, values 0,1,2 | -M |
| Strength of magnetic field [Oe=gauss] |
Strength(Amplitude) of the periodical magnetic field. | -d |
| Periodical field chaning law | The laws of changing of amplitude of the periodical magnetic field: uniform(0), sinus(1), gauss(2) | -v |
| Deviation of amplitude [%] | Deviation of amplitude of the periodical magnetic field in percent | -a |
| Amplitude distribution | Distribution of random values: amplitude of the periodical magnetic field: Normal(0), Uniform(1) | -e |
| Sigma for gauss distr. [Oe] | Sigma for gauss distribution of amplitude of periodical magnetic field | -x |
| Permanent magnetic field components X, Y and Z [Oe] |
Components X, Y, Z of permanent magnetic field, which can be added to the components of the periodical magnetic field (projection in the axis). | -I, -A, -K |
| Additional random\n magnetic field [Oe] |
Amplitude of additional random magnetic field | -q |
| Output results | Output intermediately results of simulations(spin and total magnetic field during flight) in the file {yes no} {1 0} | -S |
| Output file: polarisation | Name of file for: results - polarisation, spin components | -O |
| Output file: magneticfield | Name of file for output results - total magnetic field components | -N |
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Last modified: Sep 30 19:07:01 MEST 2003Tuesday, 03-Jul-2007 16:14:08 CEST