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

ESA has adopted Ariel (Atmospheric Remote-sensing Infrared Exoplanet Large-survey), the 4th medium-class space mission of its Cosmic Vision program. Ariel is expected to be launched in 2029 by Ariane 6 from the Guiana Space Centre in Kourou. The French team, composed of CNES, CEA and CNRS, has taken charge of the design, production and delivery of the AIRS spectrometer. Pierre Olivier Lagage, astrophysicist at Irfu, is one of the 2 co-PI for the ARIEL consortium; the other co-PI is Jean-Philippe Beaulieu from IAP.

In its standard form, double beta decay is a process in which a nucleus decays into a different nucleus and emits two electrons and two antineutrinos (2νββ). This nuclear transition is very rare, but it was detected in several nuclei with sophisticated experiments. If neutrinos are their own antiparticles, it’s possible that the antineutrinos emitted during double beta decay annihilate one another and disappear. This is called neutrinoless double beta decay (0νββ), a phenomenon never observed so far. If 0νββ is detected, we will ascertain that neutrinos are their own antiparticles, and this would be a clue as to why they get their tiny masses—and whether they played a part in the existence of our matter-dominated universe. 

The CUPID-Mo experiment, installed at the Modane Underground Laboratory, after one year of data between March 2019 and April 2020 has just set a new global limit for the detection of the signature 0νββ.

Scientists from the large cosmological survey SDSS/eBOSS have constructed the first so-called "tomographic" map of the far Universe on a very large scale, which until now only existed in one dimension, along the line of sight of the ground-based telescope. To do this, they used the latest Lyman-alpha forest data, which indirectly plot the density of matter in the direction of bright objects, the quasars. The resulting map covers a cube of 3.26 billion light-years from observations of nearly 10,000 quasars. It is a new tool for studying the history of the Universe and its structures.

This work is published in the JCAP journal (arXiv:2004.01448).

A year and a half after the delivery of the prototype cryomodule (CM00) to ESS, the first production medium beta cryomodule (CM01) has now arrived at the ESS site. It left CEA on September 22, 2020 for a two-day trip to Lund, Sweden. The Irfu teams had previously validated the RF and cryogenic performances of this cryomodule. It will be tested again on the ESS test bench before being integrated in its final position in the accelerator tunnel. This is a first step. Starting next year, ESS will receive an average of one cryomodule per month for 3 years.