The photon detection inefficiency of electromagnetic calorimeters due to photonuclear reactions has been studied at photon energies below 1 GeV using a tagged-photon beam at the KEK-Tanashi 1.3-GeV electron synchrotron. Photonuclear reactions are identified by detecting low-energy neutrons with liquid scintillation counters surrounding the sample calorimeter. For a Cesium Iodide (CsI) calorimeter with a detection threshold of 10 MeV, the inefficiency due to photonuclear reactions is 10-4 at Eγ=100MeV, and decreases to 2×10-7 at Eγ=1GeV. For a lead-scintillator sampling calorimeter, the inefficiency is larger than the above values by a factor of 2-3, reflecting the sampling effect after photonuclear reactions. By decreasing the detection threshold down to 1 MeV, the inefficiencies are reduced by a factor of 10 for both types of calorimeters.
|Number of pages||13|
|Journal||Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment|
|Publication status||Published - Nov 1 2005|
- Electromagnetic calorimeter
- Photon detection inefficiency K →πνν̄ decay
ASJC Scopus subject areas
- Nuclear and High Energy Physics