[ Identification | Description | Input parameters | Links ]

# The `MCPL_input_once` Component

Source-like component that reads neutron state parameters from a MCPL-file one time.

## Identification

- Site:
- Author: Gregory S Tucker
- Origin: European Spallation Source ERIC
- Date: Sep 2024

## Description

    Source-like component that reads neutron state parameters from a MCPL-file one time.

    MCPL is short for Monte Carlo Particle List, and is a format for sharing events
    between e.g. MCNP(X), Geant4 and McStas.

    When used with MPI, the file contents are shared between workers with each accessing
    approximately (#events in the file) / (#MPI nodes)

    %BUGS

## Input parameters

Parameters in boldface are required; the others are optional.

Name | Unit | Description | Default |
filename | str | Name of neutron mcpl file to read. | 0 |
polarisationuse |  | If !=0 read polarisation vectors from file. | 1 |
Emin | meV | Lower energy bound. Particles found in the MCPL-file below the limit are skipped. | 0 |
Emax | meV | Upper energy bound. Particles found in the MCPL-file above the limit are skipped. | FLT_MAX |
v_smear | 1 | Relative fraction for randomness in replayed particle velocity v *= (1 + v_smear * randpm1()) | 0 |
pos_smear | m | Maximum extent of random position for replayed particles | 0 |
dir_smear | deg | Maximum deviation of random direction for replayed particles | 0 |
always_smear |  | Finite values force particle property smearing for all particles | 0 |
preload |  | Load particles during INITIALIZE. On GPU preload is forced. | 0 |
verbose |  | Finite values may cause extra output (at some point in the future) | 0 |

AT ( | , | , |  | ) RELATIVE |  |
ROTATED ( | , | , |  | ) RELATIVE |

## Links

- Source code for `MCPL_input_once.comp`.

[ Identification | Description | Input parameters | Links ]