Proton irradiation of CVD diamond detectors for high-luminosity experiments at the LHC

CVD diamond shows promising properties for use as a position sensitive detector for experiments in the highest radiation areas at the Large Hadron Collider. In order to study the radiation hardn ess of diamond we exposed CVD diamond detector samples to 24~GeV/$c$ and 500~MeV protons up to a fluence of $5\times 10^{15}~p/{\rm cm^2}$. We measured the charge collection distance, the ave rage distance electron hole pairs move apart in an external electric field, and leakage currents before, during, and after irradiation. The charge collection distance remains unchanged up to $1\ times 10^{15}~p/{\rm cm^2}$ and decreases by $\approx$40~\% at $5\times 10^{15}~p/{\rm cm^2}$. Leakage currents of diamond samples were below 1~pA before and after irradiation. The particle indu ced currents during irradiation correlate well with the proton flux. In contrast to diamond, a silicon diode, which was irradiated for comparison, shows the known large increase in leakage curren t. We conclude that CVD diamond detectors are radiation hard to 24~GeV/$c$ and 500~MeV protons up to at least $1\times 10^{15}~p/{\rm cm^2}$ without signal loss

Invited PaperJosephson readout electronics for the hybrid superconducting pixel detector

We have recently demonstrated the Hybrid Superconducting Pixel Detector (HSPD) principle using a test configuration. This demonstrator device consists of a semiconductive particle detector coupled to a Josephson Tunnel Junction (JTJ) acting as current sensitive discriminator. We used Minimum Ionising Particles (MIPs) as events generators. Experimental data show the first case of MIPs detection using JTJ. The efficiency of the demonstrator circuit reaches 90% with 2 MIPs and it will be improved once the complete device will be full integrated in one circuit. A second generation demonstrator, involving an eigth channel readout scheme fully implemented with superconducting electronics is being developed and will be discussed in some detail

Effect of intense proton irradiation on properties of Josephson devices

We have experimentally investigated the effects of intense proton beam irradiation (up to 1015 p/cm2) on Josephson junctions and junction arrays. The devices we have studied were realized using state of the art full-Nb technology, employing same materials and thicknesses of common Josephson digital circuit designs. We have analysed in detail the magnetic field dependence of the junction critical current, and the quasiparticle tunneling current, in order to observe possible occurrence of permanent changes produced by the ionizing particles. No evidence of radiation induced damage on the properties of the junctions has been found

Cavity longitudinal loss factor measurements by means of a beam test facility

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