次世代加速器のカロリーメータ用Si-PAD半導体粒子検出器

米谷 文男


Abstract


   Now in Japan, construction of a 25km-long linear electron-positron collider JLC (Japan Linear Collider) which reach TeV region at a center of mass energy has been proposed.
   If the Higgs boson which is responsible for mechanism of mass generation of whole the fundamental particles is discoverd, we can are able to obtain a lot of knowledge for new physics beyond the standard model.
   The linear electron-positron collider is enable us to identify final state of a reaction cleary for whole collision energy used by elementary process, and is suitable for precision measurements.
   To accelarate energy with circular colliders, however, is limited by energy loss due to synchrotron radiation which increases as the force power of the beam energy. Therefore linear collider is chooed for JLC.
   JLC detecor is composed of a vertex detector, a central drift chamber,calorimeters and muon detectors.
   The Si-PAD detector which is made of finely segmented silicon photodiodes is a part of the calorimeters.
   Total effective area of the prototype Si-PAD detector is 17.6 cm × 17.6 cm with a number of 256 pads, each of which has a size of 1.1 cm × 1.1 cm. The Si-PAD detector was tested using beam with momentum from 1 GeV/c to 4 GeV/c at National Laboratry for High Energy Physics(KEK).
   As a result of comparison of experimental data with Monte Carlo simulation, it is ascertained that Si-PAD detector fill its funcion.