Attenuated Alpha Backgrounds in the DEAP-3600 Dark Matter Search Experiment

It appears your Web browser is not configured to display PDF files. Download adobe Acrobat or click here to download the PDF file.

Click here to download the PDF file.


DelGobbo, Phillip Mario




DEAP-3600 is a dark matter experiment using 3.3 tonnes of liquid argon as a scintillation target to directly detect Weakly Interacting Massive Particles (WIMPs), a dark matter candidate. Mitigating background sources is crucial to dark matter searches. A large background model contribution comes from attenuated alphas originating from 210Po decays within the acrylic vessel surfaces. Alphas from decays within the acrylic inner vessel and from the acrylic neck flowguide are analyzed. The activity of the inner vessel is separated into surface and bulk components, and determined to be 0.22±0.02mBq/m2 and 3.68±0.06mBq. An event rate of 53.5+30−4.6µHz is found for alphas originating from the neck flowguide. An optimized event selection is obtained, making use of machine-learning algorithms to reject neck flowguide alphas and maximize WIMP sensitivity. In 802 live-days of DEAP-3600 data, the expected upper limit on the spin-independent WIMP-nucleon interaction cross-section is 1.9×10−45cm2 (90% C.L.) for a 100GeV/c2 WIMP mass.


Elementary Particles and High Energy




Carleton University

Thesis Degree Name: 

Master of Science: 

Thesis Degree Level: 


Thesis Degree Discipline: 


Parent Collection: 

Theses and Dissertations

Items in CURVE are protected by copyright, with all rights reserved, unless otherwise indicated. They are made available with permission from the author(s).