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

The objective of the realization of efficient compact neutron sources is to make it possible to perform neutron scattering experiments, with practically the same qualities as those carried out with neutron beam lines from research reactors of the Orphée type*.

These compact sources are obtained from a protons beam of medium-energy (3-50 MeV) and high current (100 mA) impinging on a light element target as beryllium. This interaction creates a neutron emission. In order to be used routinely, the target must be able to withstand long exposure to high irradiation without loss of performance.

The IRFU (DACM, DEDIP, DIS, DPhN) and LLB teams have realized a beryllium target implanted at the exit of the high intensity proton injector - IPHI (3 MeV)

at Saclay. They show that with this device it is possible to obtain the intensity of neutrons necessary to carry out a diffraction experiment in a reasonable time, demonstrating the competitiveness of such a source for neutron scattering compared to current small and medium power nuclear reactors.

*Former research reactor at Saclay, now shutdown.

On the evening of the 28th, we could read on NASA's blog: "It's official, the alignment of NASA's James Webb Space Telescope is now complete"!

To say that all the instruments of the James Webb Space Telescope are perfectly aligned, means that the primary mirror is well adjusted. The images are already breathtaking while the adjustment phase of all the elements of the telescope is not finished yet.

For this test, the Webb telescope pointed at a star and the quality of the alignment was verified with a part of the Large Magellanic Cloud providing a dense field of hundreds of thousands of stars on all instrument sensors. Webb's three imaging instruments are NIRCam (images below at 2 microns wavelength), NIRISS (image at 1.5 microns) and MIRI (image at 7.7 microns). MIRI detects light in a lower energy range (or longer wavelength) than the other instruments, revealing the emission from interstellar clouds as well as starlight.

These images are used to assess image sharpness, but also to accurately measure and calibrate subtle image distortions and alignments between the instrument's sensors as part of the overall Webb instrument calibration process.

At Irfu, neutrino physics is studied using different sources such as reactors, accelerators and radioactive sources.

Irfu teams have been engaged for several decades in a long quest to study the neutrino in all its aspects, to understand its place in the Standard Model of particle physics and even more, but also its contribution to the evolution of the Universe since its first moments. The traditional summer conferences organized last year were an opportunity to measure the progress made by the armada of international experiments with which our institute is working to achieve this ultimate goal. A look back at year 2021, full of lessons and promises for the future...