Detailed Characterization of Nuclear Recoil Pulse Shape Discrimination in the DarkSide-50 Direct Dark Matter Experiment

Abstract

I want to express my appreciation and gratitude to my advisor, Dr. Jelena Maricic. Thank you for your support and constant encouragement. Your confidence in me has been a tremendous boost in times of doubt. I owe a special debt of gratitude to Bernd Reinhold, our post-doc during my research, who guided, argued with, tolerated and patiently instructed me until I could reasonably be called a scientist. I'm not sure what I would have done without you. A huge thank you to my fellow graduate student, friend and co-conspirator, Brianne Hackett, who has been by my side since the very beginning. Graduate school has been an amazing, world-traveling adventure, which I am so glad I was able to share with you. After all our journeys, you are truly like family to me. In my time at UH, there have been several professors who have been incredibly helpful to me. I am thankful to my committee members, Sandip Pakvasa and Olga Boric-Lubecke, for your time in getting me to this point. Thank you to Jason Kumar, whom I can always count on for a Star Wars "dark side" pun or a great movie reference, in addition to the answer to just about any physics question I could think of. I am grateful to have been able to have Xerxes Tata to teach me particle physics, who has gifted me not only with the clearest understanding of quantum mechanics anyone could hope for, but also with the knowledge of how to do my physics problems like a donkey. To John Learned, who responded to my graduate school inquiry, I owe sincerest thanks. You changed my life for the better, and I will never forget it. Working on DarkSide afforded me the opportunity to work with people from all over the world, many of whom have had a tremendous impact on me. I would like to thank Andrea Ianni, Augusto Goretti, Nicola Canci, Yura Suvorov and Marco Carlini, who supported and assisted during our multiple calibration campaigns. Your friendship and expertise were indispensable. A special thank you to Masayuki Wasa, who has always been readily available and willing to help, no matter how much was already on his plate. Thank you for never failing to answer my emails, regardless of time of day, and for all your patience with my endless questions. I am grateful for all the mentoring I received from the senior members of the collaboration, notably Peter Meyers and Emilija Pantic. Thank you for the long discussions via email and Skype, and all of your excellent feedback. I also want to thank our Paris Monte Carlo group, Davide Franco, Stefano Perasso and, especially, Paolo Agnes, for your help throughout my research experience. Thank you to Stephan Pordes for your piercing wit and great analysis questions. Your self-effacing manner belies an uncanny ability to provide real insight, which as a student I found truly useful. To my fellow DarkSide PhD students, Shawn Westerdale, Alden Fan, Andrew Watson and Luca Pagani, from whom I have benefited from both your collaboration and commiseration, thank you. Finally, I would not be here without the love and support of my family. I have always be...

CALIS—A CALibration Insertion System for the DarkSide-50 dark matter search experiment

“…The ring clamp (5) is used for rotations in the x y-plane and the tripod (6) has been used for vertical alignment of CALIS wrt. the organ pipe, which is closed by the gate valve (7). In the photograph, the vacuum pump (8) and tubing (9) are shown, which are part of the evacuation and purging system (section 2.3).…”

“…After installation on the gate valve a testing focus was the system's light and helium leak tightness, as well as validation of nitrogen and vacuum systems, as these could only be tested fully after installation. A more detailed description of tests performed at FNAL and LNGS can be found in [6,7].…”

“…The peak at ≈ 30 PE on the left (orange box) is due to a 1775 keV α + 7 Li(g.s.). The peak on the right at ≈ 270 PE (green box) is from 93.6 % of captures that lead to the7 Li excited state reaction, with the accompanying 478 keV γ-ray. The entries below 10 PE are due to PMT after-pulses.…”