The Cherenkov Telescope Array (CTA) consortium brings together 1300 scientists from 32 countries. They have published their scientific aims in a document over 200 pages long. This is the result of several years of work, and includes contributions from approximately fifteen Irfu researchers involved in X-ray and gamma-ray observatories (Fermi, Integral, XMM-Newton, H.E.S.S., etc.).
For more than 10 years now, Irfu physicists and engineers have been developing in Saclay the necessary equipment for the GBAR experiment, designed to test the behaviour of antimatter under terrestrial gravity. An important step has just been taken with the installation at the Cern of a new positron source using on an electron linac, and the transport to the Cern of the positron trapping system built at Saclay.
The new source produced its first positrons on November 17, 2017. The installation of the traps is in progress, to be operational when the antiprotons arrive, scheduled for spring 2018.
According to the ALICE collaboration at LHC (CERN), certain rare proton collisions have properties that are similar to those of a quark–gluon plasma. In the past, these properties had been observed for collisions of heavy nuclei only. The physicists are now confronted with a new enigma: how can a state of quark–gluon plasma emerge in a system as "small" as that generated by a collision between two protons?
The ScanPyramids collaboration has discovered a new void in the heart of the Kheops pyramid. This large vacuum was detected by muonic imaging techniques conducted by three separate teams from Nagoya University (Japan), CEC (Japan) and CEA/IRFU. It is the first discovery of a major internal structure of Kheops since the Middle Ages.
Similar in size to the Great Gallery, an architectural structure located in the heart of the Great Pyramid (47m long, 8m high), this new cavity, called ScanPyramids Big Void, has a minimum length of 30 metres. First observed with nuclear emulsion films installed in the Queen's Chamber (Nagoya University), then detected with a scintillator telescope installed in the same chamber (KEK), it was confirmed with gas detectors, MICROMEGAS, located outside the pyramid (CEA), and thus with a very different angle of view allowing to refine the location of this void. This is the first time that an instrument has detected a cavity located at the bottom of a pyramid from the outside.
These results were published by the ScanPyramids team on November 2, 2017 in the journal Nature.