Division of Electronics, Detectors and Computing for Physics (DEDIP)

As part of the new CLAS spectrometer project for the 12 GeV electron energy upgrade of the Jefferson Lab (USA) IRFU has been conducting R&D for more than 10 years to design and build a new generation tracker, using thin and flexible MICROMEGAS detectors that are now operating with the new CLAS12 spectrometer. After one year of installation, this tracker is operational and meets the expected characteristics with more than 95% detection efficiency and a spatial resolution of less than 100μm. After a dedicated data collection to measure the detector response, the new CLAS12 spectrometer is now collecting data for the DVCS physics experiment, where IRFU also participates and which objective is to measure the internal structure of the proton in three dimensions.
The exceptional success of the  tracker project, that results from a close collaboration between IRFU's engineering and physics departments (DEDIP, DIS and DPHN), has been an example for other projects. Let us quote  the LHC experiments for particle hunting, the muonic imaging of the pyramids, as well as a transfer of know-how to  industry.

In 2018, IRFU is participating  in a publication CUPID-0: the first array of enriched scintillating bolometers for 0νββ decay investigations which reviews a first matrix of bolometers installed in the Gran Sasso laboratory in Italy, with the objective of tracking the double beta decay without neutrino emission (0νββ) that will reveal the nature of neutrinos. This publication describes the integration of the detectors, their testing and commissioning for a first data collection that began in 2017 with the participation of IRFU and IN2P3 researchers at various stages. The test results show a very good response of the electronics and cryogenic systems. The mean value in energy resolution proves the unmatched efficiency of this technique for measuring radioactivity, which makes it possible to dissociate beta decay from alpha decay, a source of background  in this research.

The ATLAS and CMS collaborations, involving teams from CEA/IRFU and CNRS/IN2P3, announced on 4 June 2018 at the LHCP conference the direct observation of the coupling of the quark top to the Higgs boson. Studying the interaction between the Higgs boson and the heaviest elementary particle known, the quark top, is a way of investigating the effects of new physics, which must take over from the standard model.

The results of the analyses, orchestrated by IRFU/DPHP physicists, led to the observation of this rare process and are in agreement with the predictions of the standard model. In the coming years, both experiments will collect much more data and improve the accuracy of their measurements, which could reveal a deviation from the prediction of the standard model.

CMS article: https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.120.231801
arXiv link for the ATLAS article submitted to publication : https://arxiv.org/abs/1806.00425

The ATLAS and CMS collaborations, involving teams from CEA/IRFU and CNRS/IN2P3, announced on 4 June 2018 at the LHCP conference the direct observation of the coupling of the quark top to the Higgs boson. Studying the interaction between the Higgs boson and the heaviest elementary particle known, the quark top, is a way of investigating the effects of new physics, which must take over from the standard model.

The results of the analyses, orchestrated by IRFU/DPHP physicists, led to the observation of this rare process and are in agreement with the predictions of the standard model. In the coming years, both experiments will collect much more data and improve the accuracy of their measurements, which could reveal a deviation from the prediction of the standard model.

CMS article: https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.120.231801
arXiv link for the ATLAS article submitted to publication : https://arxiv.org/abs/1806.00425

The T2K collaboration, whose goal is to study and measure neutrino oscillations, is publishing new results on the interaction of neutrinos with nuclei. This study, in which the T2K group of the IRFU plays a major role, is crucial in that it allows the dominant uncertainty on the oscillation parameters to be restrained. For the first time, protons emerging from the neutrino-nucleus interaction have been characterized using new variables capable of exposing and characterizing nuclear effects.

After more than 5 years of development, including 6 months of integration work of the 12,000 separate components to a complete cryomodule, the CEA-Irfu has just validated the technology of this complex system that reached the nominal ESS accelerating field in the 4 superconducting accelerating cavities.
At the limits of technology, this is the first time that such an intense accelerating field, maintained over such long pulse durations and with such high RF power, has been measured in superconducting cavities installed in a complete cryomodule.
This key step makes it possible to start the production phase of the 30 cryomodules that France is to deliver to the ESS research infrastructure, which will be operational in Sweden in 2023. This serial integration will begin in January 2019 under the supervision of Irfu with the contribution of the company B&S France and should be completed in 2022.