[ Identification | Description | Input parameters | Output parameters | Links ]

# The `Virtual_tripoli4_input` Component

This component uses a file of recorded neutrons from the reactor monte carlo code TRIPOLI4.4 as a source of particles.

## Identification

- Author: Guillaume Campioni
- Origin: SERMA
- Date: Sep 28th, 2001
- Version: 1.10
- Modification history:
  - E. Farhi: Added automatic orientation+beam info+intensity norm

## Description

    This component generates neutron events from a file created using the
    TRIPOLI4 Monte Carlo code for nuclear reactors (as MCNP). It is used to
    calculate flux exiting from hot or cold neutron sources.
    Neutron position and velocity is set from the file. The neutron time is
    left at zero.
    Storage files from TRIPOLI4.4 contain several batches of particules, all
    of them having the same statictical weight.

    Note that axes orientation may be different between TRIPOLI4.4 and McStas.
    The component has the ability to center and orient the neutron beam to the Z-axis.
    It also may change the coordinate system from the Tripoli frame to the McStas one.
    The verbose mode is highly recommanded as it displays lots of useful informations,
    including the absolute intensity normalisation factor. All neutron fluxes in the
    instrument should be multiplied by this factor.
    The source total intensity is 1.054e18 for LLB/Saclay and 4.28e18 for ILL/Grenoble.

    Format of TRIPOLI4.4 event files is :

      NEUTRON energy position_X position_Y position_Z dir_X dir_Y dir_Z weight

    energy is in Mega eV
    positions are in cm and the direction vector is normalized to 1.

    EXAMPLE:
    To create a 'source' from a Tripoli4 simulation event file for the ILL:
    COMPONENT source = Virtual_tripoli4_input(
       file = "ILL_SFH.dat", intensity=4.28e18,
       repeat_count  = 1, verbose = 1, autocenter="translate rotate")

WARNING: This is a contributed Component.

## Input parameters

Parameters in boldface are required; the others are optional.

Name | Unit | Description | Default
--- | --- | --- | ---
file | str | Name of the Tripoli4.4 neutron input file | 0
autocenter | str | String which may contain following keywords. "translate" or "center" to center the beam area AT (0,0,0) "rotate" or "orient" to center the beam velocity along Z "change axes" to change coordinate system definition Other words are ignored. | 0
repeat_count | 1 | Number of times the source must be generated. 0 unactivates the component | 1
verbose | 0|1 | Displays additional informations if set to 1 | 0
intensity | n/s | Initial total Source integrated intensity | 1

## Output parameters

Name | Unit | Description | Default
--- | --- | --- | ---
hfile |  |  |
head | char | header buffer |
nl | long | nb of lines in header |
rep |  |  |
begin_of_file |  |  |
begin_batch |  |  |
do_rotate |  |  |
do_translate |  |  |
do_axes |  |  |
bx |  |  |
by |  |  |
bz |  |  |
angle2z | double, rad | rotation angle required to orient beam along Z axis |
nbatch | long | number of read neutron batches |
nsize |  |  |
mean_x | double | \ |
mean_y | double | source center coordinates |
mean_z | double | / |

## Links

- Source code for `Virtual_tripoli4_input.comp`.
- Tripoli
- Virtual_tripoli4_output
- CAMPIONI Guillaume, Etude et Modelisation des Sources Froides de Neutrons, These de Doctorat, CEA Saclay/UJF (2004)

[ Identification | Description | Input parameters | Output parameters | Links ]