# Detector response

(Difference between revisions)
 Revision as of 09:53, 23 September 2009 (view source)Greilich (Talk | contribs)← Older edit Latest revision as of 09:53, 23 September 2009 (view source)Greilich (Talk | contribs) Line 10: Line 10: * Si detectors * Si detectors - can be very different when exposed to a particle beam instead of gamma or x-ray radiation. The reason is the high ioziation density in tracks of particle with high LET compared to the more homogenenous energy deposition of photon and x rays ('sea of electrons') or even high energy (='low LET') particles. + can be very different when exposed to a particle beam instead of gamma or x-ray radiation. The reason is the high ioziation density in tracks of particle with high LET compared to the more homogenenous energy deposition of photon and x rays ('sea of electrons') or even high energy (='low LET') particles. Rather than in absolute terms of detector response this behaviour is more often described by the means of 'relative detector efficiancy'. Here, the response of the detector in a radiation field Q at dose D is compared to the response in a low LET field such as Co-60: - + - Rather than in absolute terms of detector response this behaviour is more often described by the means of 'relative detector efficiancy'. Here, the response of the detector in a radiation field Q at dose D is compared to the response in a low LET field such as Co-60: + $\eta = \frac{S_Q(D)}{S_{Co-60}(D)}$ $\eta = \frac{S_Q(D)}{S_{Co-60}(D)}$

## Detector efficiency

The response of a solid state detector, such as

• Thermoluminescence detectors (TLDs)
• Detectors based on optically stimulated luminescence (OSDs)
• Scintillators
• Alanine(EPR)
• Si detectors

can be very different when exposed to a particle beam instead of gamma or x-ray radiation. The reason is the high ioziation density in tracks of particle with high LET compared to the more homogenenous energy deposition of photon and x rays ('sea of electrons') or even high energy (='low LET') particles. Rather than in absolute terms of detector response this behaviour is more often described by the means of 'relative detector efficiancy'. Here, the response of the detector in a radiation field Q at dose D is compared to the response in a low LET field such as Co-60:

$\eta = \frac{S_Q(D)}{S_{Co-60}(D)}$

N.B. that this definition is slightly different than the one for RBE in radiobiology.

Amorphous track models are intended to predict the differences in (relative) response.