Neganov-Luke amplified cryogenic light detectors for the background discrimination in neutrinoless double beta decay search with TeO₂ bolometers

We demonstrate that Neganov-Luke amplified cryogenic light detectors with Transition Edge Sensor read-out can be applied for the background suppression in cryogenic experiments searching for the neutrinoless double beta decay of ¹³⁰Te with TeO2 based bolometers. Electron and gamma induced events can be discriminated from α events by detecting the Cherenkov light produced by the β particles emitted in the decay. We use the Cherenkov light produced by events in the full energy peak of ²⁰⁸Tl and by events from a ¹⁴⁷Sm source to show that at the Q-value of the neutrinoless double beta decay of ¹³⁰Te (Qβ β = 2.53 MeV), a separation of e^-/γ events from α events can be achieved on an event-by-event basis with practically no reduction in signal acceptance.