Project description
BINGO! No neutrinos where there should have been two!
The Standard Model of particle physics has been the 'standard' description of our universe since the 1970s, despite recognition that, for all its detail, it leaves some important areas open. The 12 matter particles, six quarks and six leptons, each have an 'anti-matter' particle; when these particles meet, they annihilate each other. The antiparticle looks and behaves like the particle but has an opposite charge – or so the story goes. Three of the leptons are neutrinos of different types – neutral particles with no charge, further complicating the antiparticle theory. Indirect evidence suggests that neutrinos may be their own antiparticles. Observation of the so-called neutrinoless double beta decay would provide evidence of that as it involves no neutrinos where there should have been two. The EU-funded BINGO project is developing a prototype of a highly sensitive detector for an upcoming particle experiment whose outcome could lead to new physics.
Objective
BINGO will set the grounds for a large-scale bolometric experiment searching for neutrinoless double beta decay with a background index of about 10-5 counts/(keV kg y) and with very high energy resolution – of the order of 1.5‰ – in the region of interest. These features will enable a search for lepton number violation with unprecedented sensitivity. The BINGO approach can lead to the demonstration of the Majorana nature of neutrino even in the unfavourable case of direct ordering of neutrino masses.
BINGO is based on luminescent bolometers for the rejection of the dominant alpha surface background. It will focus on two extremely promising isotopes – 100Mo and 130Te – that have complementary merits and deserve to be both considered for future large-scale searches.
The project will bring three original ingredients to the well-established technology of hybrid heat-light bolometers: i) the light-detector sensitivity will be increased by an order of magnitude thanks to Neganov-Luke amplification; (ii) a revolutionary detector assembly will reduce the total surface radioactivity contribution by at least one order of magnitude; (iii) for the first time in an array of macrobolometers, an internal active shield, based on ultrapure ZnWO4 scintillators with bolometric light readout, will suppress the external gamma background. These challenging technologies will be extensively tested in a two-isotope demonstrator, dubbed MINI‑BINGO, which will be located in an underground laboratory in a dedicated cryogenic infrastructure built with ERC funds.
The BINGO approach can be implemented in the next-generation search CUPID, a proposed follow up of the CUORE experiment. BINGO can improve dramatically the sensitivity of CUPID, using two isotopes at the same time and providing the demonstration of its background goal. Subsequently, the intrinsic modularity of the bolometric technique would make sensible to proceed to further expansions, capable of penetrating the direct-ordering band.
Fields of science
Programme(s)
Funding Scheme
ERC-COG - Consolidator GrantHost institution
75015 PARIS 15
France