[ Identification | Description | Input parameters | Links ]

# The `Tools_ONION` Instrument

## Identification

- Site: Mantid
- Author: Thomas Huegle
- Origin: ORNL
- Date: July 2019

## Description

    Test case for an layered detector shell instrument to provide quick overview of resolution per pixel.
    Set up to be run in McStas -> Mantid mode, refer to manual for details on execution.
    Simulates desired divergence by adjusting moderator size.
    Considers only in-plane (xwidth) factors, sets yheight as 1 cm.
    For an example on how to analyze the data, see the 'Onion_analyzerScript.py' available at
    https://github.com/McStasMcXtrace/McCode-contribution-support-docs/tree/master/McStas/2.6_Onion_tool_T_Huegle

    Acceptable statistics can be achieved by running the simulation with 1E7 neutrons (output file: ~400MB)

## Input parameters

Parameters in boldface are required; the others are optional.

Name | Unit | Description | Default
divergence | degrees | angular divergence of neutrons reaching the sample | 0.4
distance | m | distance between source and sample | 32
filename |  |  | "source_sct521_bu_08_1.dat"

## Links

- Source code for `Tools_ONION.instr`.
- "Using an onion like neutron scattering instrument model to quickly optimize design parameters"
- T. Huegle, Nuclear Instruments and Methods in Physics Research Section A, 2019
- Python script available at https://github.com/McStasMcXtrace/McCode-contribution-support-docs/tree/master/McStas/2.6_Onion_tool_T_Huegle

[ Identification | Description | Input parameters | Links ]