The goal of the SoLid experiment is to conduct a search for active-to-sterile anti-neutrino oscillation at a very short distance (6.3-8.9 m) from the core of the SCK-CEN BR2 research reactor in Mol, Belgium, and provide a unique and complementary test of the so-called Reactor Antineutrino Anomaly. A secondary objective of the experiment is to measure the pure U-235 antineutrino spectrum with a few percent level precision.
SoLid uses an innovative antineutrino detection technique based on a highly segmented target volume made of PVT cubes and LiF:ZnS phosphor screens. The combination of scintillator signals provides a unique signature in space and time to localise and identify the products of the inverse beta decay. A ML-EM based algorithm enables the reconstruction of the full 3D event topologies and machine learning-based pulse shape discrimination provides the capability to reject effectively internal Bi-Po and external fast neutron backgrounds. In the first phase of the experiment, SoLid has been taking data from early 2018 to summer 2020.
In this poster we will be presenting the dataset used to select the inverse beta decay (IBD) events, the performance and validation of the IBD selections developed around boosted decision trees and the methods to extract the IBD yields using reactor OFF and reactor ON datasets. Systematics errors and recent results for the oscillation analysis will also be presented.