# 2019 CAP Congress / Congrès de l'ACP 2019

2-7 June 2019
Simon Fraser University
America/Vancouver timezone
Welcome to the 2019 CAP Congress Program website! / Bienvenue au siteweb du programme du Congrès de l'ACP 2019 !

## 85 - Modelling emission of acoustic energy during bubble expansion in PICO bubble chambers

4 Jun 2019, 17:37
2m
SWH 9082 + AQ South-East Corner / coin sud-est (Simon Fraser University)

### SWH 9082 + AQ South-East Corner / coin sud-est

#### Simon Fraser University

Poster Competition (Undergraduate Student) / Compétition affiches (Étudiant(e) du 1er cycle) Particle Physics / Physique des particules (PPD)

Tetiana Kozynets

### Description

The PICO experiment uses bubble chambers filled with superheated C$_3$F$_8$ for spin-dependent WIMP dark matter searches. One of the main sources of background in these detectors is alpha particles from decays of environmental $^{222}\mathrm{Rn}$, which nucleate bubbles that are visually indistinguishable from WIMP candidate events. It was previously determined that alpha-induced bubbles can be discriminated against acoustically, based on the signal from alpha events being consistently larger in magnitude than from nuclear recoil/WIMP-like events. By studying the dynamics of bubbles nucleated by these two types of ionizing radiation from the first stages of their growth, we develop a physical model for the acoustic discrimination for the first time. This model is verified by comparing the simulated and the experimental distributions of acoustic energies radiated during bubble expansion.

Tetiana Kozynets

### Co-authors

Dr Scott Fallows (University of Alberta) Prof. Carsten Krauss (University of Alberta)

### Presentation Materials

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