[ Identification | Description | Input parameters | Links ]

# The `Brilliance_monitor` Component

Special "Brilliance" monitor.

## Identification

- Site:
- Author: Peter Willendrup, derived from TOF_lambda_monitor.comp
- Origin: DTU Physics
- Date: May 23, 2012

## Description

    If used in the right setting, will output "instantaneous" and "mean" brilliances in units of Neutrons/cm^2/ster/AA/s. Conditions for proper units:

    Use a with a source of area 1x1cm
    The source must illuminate/focus to an area of 1x1cm a 1m distance
    Parametrise the Brilliance_monitor with the frequency of the source
    To not change the source TOF distribution, place the Brilliance monitor close to the source!

    with a source of area 1x1cm illuminating/focusing to an area of 1x1cm a 1m distance, this monitor will output "instantaneous" and "mean" brilliances in units of Neutrons/cm^2/ster/AA/s

    Here is an example of the use of the component. Note how the mentioned Unit conditions are implemented in instrument code.

    COMPONENT Source = ESS_moderator_long(
    l_low = lambdamin, l_high = lambdamax, dist = 1, xw = 0.01, yh = 0.01,
    freq = 14, T=50, tau=287e-6, tau1=0, tau2=20e-6,
    n=20, n2=5, d=0.00286, chi2=0.9, I0=6.9e11, I2=27.6e10,
    branch1=0, branch2=0.5, twopulses=0, size=0.01)
    AT (0, 0, 0) RELATIVE Origin

    COMPONENT BRIL = Brilliance_monitor(nlam=196,nt=401,filename="bril.sim",
    t_0=0,t_1=4000,lambda_0=lambdamin,
    lambda_1=lambdamax, Freq=14)
    AT (0,0,0.000001) RELATIVE Source

## Input parameters

Parameters in boldface are required; the others are optional.

Name | Unit | Description | Default |
nlam | 1 | Number of bins in wavelength | 101 |
nt | 1 | Number of bins in TOF | 1001 |
nowritefile | 1 | If set, monitor will skip writing to disk | 0 |
lambda_0 | AA | Minimum wavelength detected | 0 |
lambda_1 | AA | Maximum wavelength detected | 20 |
restore_neutron | 1 | If set, the monitor does not influence the neutron state | 0 |
Freq | Hz | Source frequency. Use freq=1 for reactor source |  |
tofcuts | 1 | Flag to generate TOF-distributions as function of wavelength | 0 |
toflambda | 1 | Flag to generate TOF-lambda distribution output | 0 |
xwidth | m | width of monitor | 0.01 |
yheight | m | height of monitor | 0.01 |
source_dist | m | Distance from source. Beware when transporting through neutron optics! | 1 |
filename | string | Defines filenames for the detector images. Stored as: Peak_<filename> and Mean_<filename> | 0 |
t_0 | us | Minimum time | 0 |
t_1 | us | Maximum time | 20000 |
srcarea |  | Source area [cm^2] | 1 |

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

## Links

- Source code for `Brilliance_monitor.comp`.

[ Identification | Description | Input parameters | Links ]