Long-term performance of double gap resistive plate chambers under gamma irradiation
In this paper, we describe a dedicated test to study possible long-term aging effects on Resistive Plate Chambers (RPCs). A double gap detector was operated under gamma irradiation for a period approximately equal to 10 years of LHC in the CMS-barrel region: an integrated dose of about and a total charge of about gap were accumulated on the chamber. The results show no relevant aging effect. Also the RPC sensitivity to gamma energies is measured.
Abstract A layer of random defects in the simple cubic Ising model with nearest neighbor ferromagnetic interactions of strength J is considered. Using the real space renormalization group method we calculate defect free energy in the whole temperature range. Specifically, we analyze: the layer of diluted defects, the layer of spin-glass type defects, and the layer of mixed defects. The free energy is strongly dependent on the value of couplings between the defect and the bulk.