objective: maintaining the health of oral tissues is a major goal in dentistry. however, limitations in dental materials, instruments, procedures and medications prevent achievement of this goal. advances in nanotechnology have paved the way to approach this goal. this study reviews the advances on nanotechnology in dentistry. review of literatures: in this review study, google scholar, pubmed,...

The intention of this research project was to calculate the e/π ratio for the proposed Shashlik Detector for the Compact Muon Solenoid Experiment by simulating proton collision events in a virtual detector. The e/π ratio is the ratio of the Shashlik’s ability to measure the energy of electromagnetic to hadronic particles. An upgrade is required for the electromagnetic calorimeter due to radiati...

Avalanche photodiodes will be used to detect scintillation light from PbWO4 crystals in the CMS electromagnetic calorimeter. Properties of Hamamatsu APD are reported and special attention has been devoted to the study of radiation hardness and room temperature annealing. We found a fast recovery with a time constant of 1.3 days, a medium fast recovery with of the order of 10 days and indication...

In the context of ClearMind project, we measured scintillating properties, as induced from gamma ray interactions, today available PbWO4 crystal. We scintillation s yields and time constants by measuring signal shape on a fast photo-multiplier deconvoluting it instrumental effects. For doped crystals at room temperature, component, with 2 ns, 55 percent total light yield, slow component 6 ns. o...

The Heavy Photon Search Experiment (HPS) is a new experiment at Jefferson Lab designed to look for massive vector gauge bosons (heavy photons) in the mass range 20-1000 MeV/c which couple to electrons with couplings α/α in the range 10 to 10 . The experiment utilizes a compact forward spectrometer employing silicon microstrip detectors for vertexing and tracking and a PbWO4 electromagnetic calo...

The effect of external as well as internal bremsstrahlung radiation in H ! ZZ ! 4e channel is studied in full detector simulation. A method is proposed for external and internal bremsstrahlung recovery, allowing us to use 95% of electrons within j E=pgen 1 j 0.2. It is shown that traditional E=p and isolation cuts can be implemented with 90% efficiency, but that precise mass reconstruction is a...

The time resolution of scintillation detectors of ionizing radiation is one of the key parameters sought for in the current and future high-energy physics experiments. This study is encouraged by the necessity to find novel detection methods enabling a sub-10-ps time resolution in scintillation detectors and is focused on the exploitation of fast luminescence rise front. Time-resolved photolumi...

Light monitoring will serve as an intercalibration for compact muon solenoid (CMS) lead tungstate crystals in situ at the large hadronic collider, which is crucial for maintaining crystal calorimeter’s subpercent constant term in the energy resolution. This paper presents the design of the CMS electromagnetic calorimeter monitoring light source and high-level distribution system. The correlatio...