Difference between revisions of "CrossTalk"

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=Detector physics=
 
=Detector physics=
 
==Summary==
 
==Summary==
Neutron energy deposition from collisions with hydrogen and carbon are converted to electron equivalent light output by MCNP-POLIMI. Neutron collisions occurring over a pulse collection time window of 10 ns are converted to MeVee and summed. When pulse's total light output exceeds 0.3 MeVee, it is considered a detection.  The value 0.03 MeVee was chosen as the detector's light output threshold because it corresponds to a mean neutron energy deposit of 0.2 MeV.  
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Neutron energy deposition from collisions with hydrogen and carbon are converted to electron equivalent light output by MCNP-POLIMI. Neutron collisions that all occur whithin a pulse collection time of 10 ns of each other are summed. If a pulse's total light output exceeds 0.03 MeVee, it is considered a detection.  The value 0.03 MeVee was chosen as the detector's light output threshold because it corresponds to a mean neutron energy deposit of 0.2 MeV.  
 
 
  
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==Detectpor responce==
 
The electron equivalent (MeVee) conversion functions for neutrons were measured for plastic (BC 420) scintillators as a function of neutron energy deposit, <math>E_{n}</math>. For deposit on hydrogen the measurements fit the following quadratic function:   
 
The electron equivalent (MeVee) conversion functions for neutrons were measured for plastic (BC 420) scintillators as a function of neutron energy deposit, <math>E_{n}</math>. For deposit on hydrogen the measurements fit the following quadratic function:   
  

Revision as of 21:35, 18 July 2016

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Geometry

An array of 6 detectors are placed radially at a distance of 1 meter from an uncorrelated 252-CF source. The image below shows a top down view of the simulation geometry. The detector setups have a vertical extent of 30".

GeomEdited.png

Detector physics

Summary

Neutron energy deposition from collisions with hydrogen and carbon are converted to electron equivalent light output by MCNP-POLIMI. Neutron collisions that all occur whithin a pulse collection time of 10 ns of each other are summed. If a pulse's total light output exceeds 0.03 MeVee, it is considered a detection. The value 0.03 MeVee was chosen as the detector's light output threshold because it corresponds to a mean neutron energy deposit of 0.2 MeV.

Detectpor responce

The electron equivalent (MeVee) conversion functions for neutrons were measured for plastic (BC 420) scintillators as a function of neutron energy deposit, [math]E_{n}[/math]. For deposit on hydrogen the measurements fit the following quadratic function:

[math]L=0.036E_{n}^{2}+0.125E_{n}[/math]

and for deposit on carbon:

[math]L=0.02E_{n}[/math]

A light output of 0.03 MeVee corresponded to an average neutron energy deposition of 0.2 MeV in the scintillator.

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