Cross section measurement of simultaneously produced Υ(1S) + J/Ψ mesons and upgrade studies for the CMS detector

A measured cross section of simultaneously produced Υ(1S) and J/ψ mesons is performed using 20 fb^-1 integrated luminosity in proton-proton collisions at √s=8 TeV center of mass energy recorded by the CMS detector. Both mesons are fully reconstructed from their final states, μ+ μ-. To extract the signal yield, an extended maximum likelihood fit is used on two (invariant mass of Υ(1S) and J/ψ ) dimensional components. The cross section in the fiducial region, defined as |y|<2.0, is determined to be 16.5±3.6(stat)±2.6(syst) pb. The silicon pixel detector is close to the interaction point of the CMS detector, so it is exposed to a very harsh radiation environment. The silicon sensors of the pixel detector need to be replaced from time to time because of radiation damage. For the next interaction, a silicon sensor must resist an integrated luminosity of 300 fb^-1. The silicon wafers that were made by Sintef were tested to check the capability of the sensors to be used for Phase I upgrade. Due to increasing integrated luminosity at particle accelerators, radiation hard detectors are needed. Secondary Emission Ionization Calorimetry is a new technique for high radiation conditions. The purpose is to design an SE module from a conventional PMT mode for secondary emission ionization calorimetry.