The Background Model for the CUPID Experiment*

The abundance of matter in the universe is one of the most plainly obvious yet deceptively difficult to explain facts in modern physics. All of our known laws of physics conserve the net abundance of matter and antimatter; yet, it is apparent that at some point in the early universe, that symmetry must have been violated. We can search for vestiges of this symmetry violation by searching for a process called Neutrinoless Double Beta (0$\nu\beta\beta$) decay. The CUORE Upgrade with Particle Identification (CUPID) is a next generation search for 0$\nu\beta\beta$ decay in $^{100}$Mo, with sensitivity to $m_{\beta\beta}$ in the so-called Inverted Hierarchy region. CUPID is the successor to the CUORE experiment and adds the ability to significantly reduce radioactive backgrounds to our signal through the use of a powerful particle identification technique. In order to achieve its sensitivity goal, CUPID must achieve a stringent background level of 10$^{-4}$~counts/(keV$\cdot$kg$\cdot$yr) in the 0$\nu\beta\beta$ decay region of interest — a decrease of 2 orders of magnitude over the backgrounds achieved in CUORE. In this talk, I will describe the projected background model for CUPID, focusing on the major background sources, and the mitigation techniques employed to reduce them.