Contribution to the Global Digital Compact: “Digital commons as a global public good. Internet as a free space, and methods for combating the spread of disinformation and misinformation.”

The Internet as a common good implies the absence of any restrictions, closures, and blockages with censorship being unacceptable in democratic societies. However, it can lead to the uncontrolled growth and spread of disinformation and misinformation, which can have negative effects on democratic processes, on emergency management, and on human rights. While part of society sees the Internet as the last free space and considers the restriction of the Internet an infringement of citizens’ rights to freedom of communication and information, another part of society advocates at least reasonable censorship of the Internet. Parallel to this is the question of who will be behind the censorship – will it be the government, private companies, platforms, or search engines, and what will be the rules and algorithms of censorship. As part of its participation in the CORE project (sCience&human factOr for Resilient sociEty), IIASA held an online consultation with project participants to discuss the topic of “Internet as a free space and methods for combating the spread of disinformation and misinformation” and to prepare key principles and commitments as a contribution to the Global Digital Compact. This report provides a comprehensive overview of the key points raised by the participants in the consultation proces

Pion irradiation studies of CVD diamond detectors

We report here the results of a test to ascertain the radiation hardness properties of CVD diamond detectors to 300 MeV/c pions. In this test, CVD diamond detectors were exposed to 8 \times 10^{13} pions per cm^2 using the high intensity pion beam at the Paul Scherrer Institut. For comparison, silicon photodiodes were exposed to similar fluences at the same time. The measurements and the dosimetry during the irradiations are described herein. As expected, the silicon devices degraded. The diamond devices showed no degradation in collected charge and no increase in leakage current

Micro-strip sensors based on CVD Diamond

In this article we present the performance of recent chemical vapour deposition (CVD) diamond micro-strip sensors in beam tests. In addition we present the first comparison of a CVD diamond micro-strip sensor before and after proton irradiation

Performance of irradiated CVD diamond micro-strip sensors

CVD diamond detectors are of interest for charged particle detection and tracking due to their high radiation tolerance. In this article we present, for the first time, beam test results from recently manufactured CVD diamond strip detectors and their behavior under low doses of electrons from a $\beta$-source and the performance before and after intense ($>10^{15}/{\rm cm^2}$) proton- and pion-irradiations. We find that low dose irradiations increase the signal-to-noise ratio (pumping of the signal) and slightly deteriorate the spatial resolution. Intense irradiations with protons ($2.2\times 10^{15}~p/{\rm cm^2}$) lowers the signal-to-noise ratio slightly. Intense irradiation with pions ($2.9\times 10^{15}~\pi/{\rm cm^2}$) lowers the signal-to-noise ratio more. The spatial resolution of the diamond sensors improves after irradiations

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

Development of CVD diamond radiation detectors

Diamond is a nearly ideal material for detecting ionizing radiation. Its outstanding radiation hardness, fast charge collection and low leakage current allow a diamond detector to be used in high ra diation, high temperature and in aggressive chemical media. We have constructed charged particle detectors using high quality CVD diamond. Characterization of the diamond samples and various detect ors are presented in terms of collection distance, $d=\mu E \tau$, the average distance electron-hole pairs move apart under the influence of an electric field, where $\mu$ is the sum of carrier mo bilities, $E$ is the applied electric field, and $\tau$ is the mobility weighted carrier lifetime. Over the last two years the collection distance increased from $\sim$ 75 $\mu$m to over 200 $\mu$ m. With this high quality CVD diamond a series of micro-strip and pixel particle detectors have been constructed. These devices were tested to determine their position resolution and signal to n oise performance. Diamond detectors were exposed to large fluences of pions, protons and neutrons to establish their radiation hardness properties. The results of these tests and their correlati on with the characterization studies are presented

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