# The projected background for the CUORE experiment

## TL;DR

This paper presents a detailed background projection for the CUORE experiment, aiming to detect neutrinoless double beta decay of 130Te, by using Monte Carlo simulations informed by material screening and measurements.

## Contribution

It provides a comprehensive background model for CUORE based on simulations and material data, guiding the experiment's construction and sensitivity goals.

## Key findings

- Projected background rate in the region of interest is below 10^{-2} counts/keV/kg/y.
- Simulation results inform construction strategies to optimize sensitivity.
- Background modeling supports reaching the 9×10^{25} year half-life sensitivity.

## Abstract

The Cryogenic Underground Observatory for Rare Events (CUORE) is designed to search for neutrinoless double beta decay of 130Te with an array of 988 TeO2 bolometers operating at temperatures around 10 mK. The experiment is currently being commissioned in Hall A of Laboratori Nazionali del Gran Sasso, Italy. The goal of CUORE is to reach a 90\% C.L. exclusion sensitivity on the \tect decay half-life of 9$\times$10$^{25}$ years after 5\,years of data taking. The main issue to be addressed to accomplish this aim is the rate of background events in the region of interest, which must not be higher than 10$^{-2}$\,counts/keV/kg/y. We developed a detailed Monte Carlo simulation, based on results from a campaign of material screening, radioassays, and bolometric measurements, to evaluate the expected background. This was used over the years to guide the construction strategies of the experiment and we use it here to project a background model for CUORE. In this paper we report the results of our study and our expectations for the background rate in the energy region where the peak signature of neutrinoless double beta decay of 130Te is expected.