Simulation of a detection setup for the measurement of fission beta spectra in the context of reactor antineutrinos

Full description

The reactor antineutrino anomaly, namely a significant deficit of 5.5 +/- 1.2 % in the number of antineutrinos detected at short distance from the reactors remains an enigma. The results of several large-scale experiments, including the one carried out by our laboratory with the STEREO detector at the high flux reactor of Grenoble, confirm the anomaly but reject the hypothesis initially proposed, an oscillation of antineutrinos towards a sterile state. The current hypothesis is the existence of biases in the prediction obtained from reference beta spectra, measured in the 1980s with the BILL magnetic spectrometer at the Grenoble reactor. The prediction of antineutrino spectra directly from actual nuclear data, and thus without using the BILL measurements, is also possible but the uncertainties are dominated by errors and/or gaps in the beta decay data (Pandemonium effect).

The internship will consist in simulating a new device allowing to measure the beta spectra of fission fragments and to improve the prediction of the antineutrino spectrum. This device will be installed first on the Lohengrin fission fragment spectrometer of the ILL and then on the FIPPS spectrometer of the ILL. The internship work will be to implement the geometry of the detectors with the GEANT-4 library and to optimize their dimensions.

A good background in nuclear physics and a pronounced interest in experimental work is essential. The simulation will be implemented in C++ on GEANT4. This internship, whose duration may be adapted from 3 to 6 months, requires very good programming skills.

Location

Saclay

Internship conditions

• Internship duration: 36 months
• Level of study: Bac+4/5
• Training: Ingenieur/Master
• Continuation in PhD thesis: No
• Application deadline: 16 janvier 2023

Useful methods and technics:
– C++ using ROOT (CERN) libraries.
– Simulation with GEANT4.

Computer languages and software:
C++, ROOT, GEANT4

Supervisor

Materna Thomas
Phone: +33 1 69 08 40 91
Email :

Head of the laboratory DPhN / LEARN

Letourneau Alain
Phone: +33 1 69 08 76 01