Elementary Particles and Fields and String Theory Commons^™

Muon Lifetime: Theory, Experiment, And Simulation, Soren Agustin Munoz

Physics

This senior project investigates the muon lifetime through three complementary approaches: theoretical calculation, laboratory measurement, and computational simulation. The theoretical component develops the necessary background from relativistic field theory to the effective weak interaction, culminating in the leading-order Fermi-theory prediction of τ ≈ 2.2 μs, which explains why the muon lifetime lies on the microsecond scale.

The experimental component measures the lifetime of stopped cosmic-ray muons using a plastic scintillator, photomultiplier tube, and analog timing electronics. A binned Poisson likelihood fit to the primary 15-day acquisition run τ = 2.17^+0.03_-0.09 μs, consistent with the accepted value within the …

Validation Of Electromagnetic Shower Development In A Reduced Alice Focal-E Detector Model Using Geant4, Isaac Lara Romo

Physics

This project focuses on the preliminary simulation of a reduced FoCal-E detector model for the ALICE experiment at CERN. Beamline tests were simulated using an electron gun at various incident energies, and the results were compared with those of the FoCal group. The longitudinal charge deposition per sensor layer was compared between the two setups to verify that the reduced model exhibited expected calorimeter behavior. Additionally, the transverse signal across the high-granularity sensor layers was examined to determine whether the reduced model reproduced the expected lateral development of electromagnetic showers. The results obtained from these measurements show that the reduced …

The Implementation Of Scintillation Detectors With The Cuore/Cupid Collaboration In The Search For Neutrinoless Double Beta Decay, Reese Sandra Cormier

Physics

CUORE (Cryogenic Underground Observatory for Rare Events) is an experiment at the Gran Sasso National Laboratory in Assergi, Italy, currently searching for an answer to the matter-antimatter asymmetry problem; the question: why do we exist? One proposed explanation is neutrinoless double beta decay, a theorized exotic decay that would prove that neutrinos are their own antiparticle, violating the current Standard Model for particle physics. However, current detection methods do not distinguish different types of particle interactions, resulting in alpha decays contributing to the background. Therefore, the experimental sensitivity is too limited to make confident determinations about the data. For this …

Experimental Methods For Cryogenic Rare Event Detection: Cuore And Cupid, Alessandro Libenson

Physics

This senior project was written with the primary purpose of serving as a introductory guide for undergraduate students learning about the experimental methods used in the CUORE and CUPID Collaborations. In particular, this project is geared towards getting students in Dr. Gutierrez's research group at Cal Poly up to speed on what CUORE and CUPID actually do. I wrote this as an undergraduate aiming to help future undergraduates. For Cal Poly students, I would suggest the following prerequisites before reading this paper: Electronics and Instrumentation, Quantum Laboratory 1, and the equivalent of the coding/analysis class. It is also important to …

The Gauge/Gravity Holographic Duality Between String Theory And Quantum Field Theory: A Full Introduction, Alex A. Short

Physics

The Anti-deSitter Spacetime / Conformal Field Theory (AdS/CFT) correspondence is a well known holographic duality between ten dimensional superstring theories and conformal quantum field theories. The existence of such a correspondence is fascinating and the duality provides a powerful tool-set for working out problems in both string theory and quantum field theory. The correspondence defines a dictionary of terms that exist dual to one another in each theory, allowing theorists to understand the dynamics in one system based on quantities from another. Furthermore, when one side of the duality has strong coupling (meaning the approximations of perturbation theory are no …

Muon Veto Panel Uniformity Tests At Yale Wright Laboratory For The Cuore And Cupid Experiments And Visualizing Dirac Spinors In The Chiral Basis With The Bloch Sphere, Reagen Neeva Garcia

Physics

This senior project is divided into three sections that describe my path and experiences in under graduate research. The first provides an introduction to the field of particle physics and the search for neutrinoless double beta decay (0νββ) with the Cryogenic Underground Observatory for Rare Events (CUORE) experiment, as well as its upgrade, CUPID (CUORE Upgrade with Particle IDentification). The second section details my contributions to these experiments, including my summer working at Yale’s Wright Laboratory on R&D for the CUPID experiment. In this section I describe my work on the experiment’s muon veto system and on light detector development …

Non-Relativistic Limit Of Selected Terms From The Sme Dirac Lagrangian, Quinn Reece

Physics

We examine a selection of individual CPT/Lorentz violating terms present in the relativistic lagrangian for a free spin- 1 2 Dirac fermion of mass m in the Standard Model Extension. Euler-Lagrange relations will be applied to give Dirac-like equations including these terms and a novel procedure will be used to generate non-relativistic limits of these equations which are Schr¨odinger-Pauli-like equations. These equations will be analyzed using classical quantum mechanics toy problems to gain physical intuition for the effects of the CPT violating terms, and the results will be discussed. We will conclude with discussion on future work will include the …

Lorentz Violations And The Casimir Effect, Samuel G. Christensen

Physics

The background and calculation for the corrections to the Casimir Energy stored on parallel conducting plates due to minimal violations of Lorentz invariance are presented as a test of the Standard Model. A direction-dependent photon dispersion relation using operators of dimension 4 and higher is used in the calculation of the spacetime anisotropy correction terms to the Casimir energy. The calculation includes discussion of Riemann zeta function regularization and its equivalence to Euler-Maclaurin sum-integral formulas in a Casimir effect calculation. The two plate geometry result is mapped onto a one plate and sphere geometry to cater to modern precision tests …

Lorentz Violation In Neutrino Interactions, Pranav Jayaram Seetharaman

Physics

Both the Standard Model of particle physics and General Relativity require Lorentz symmetry as a fundamental building block. In this paper, we learn about a framework called the Standard Model Extension that allows us to determine how physical phenomenon would change if we deviated from Lorentz invariance in the Standard Model and General Relativity. We use the Standard Model Extension to analyze a specific high-energy, astrophysical neutrino interaction that is only possible if Lorentz symmetry can be broken. The interaction we look at is the decay of a neutrino into an electron-positron pair, which is not possible in conventional physics. …

Pnnl Dark Matter Bubble Chamber Simulation, Carl M. Krutz

STAR Program Research Presentations

Based on observations of interactions between objects on a cosmic scale, scientists have determined that a large percentage (85%) of the universe’s mass is not visible. Weakly Interacting Massive Particles (WIMPs) are one of the primary candidates for this dark matter. Many current projects seek to find WIMPs through various search methods. The PICO dark matter experiment involves observing an underground chamber at SNOLAB for bubbles created when energy in the form of radiation is deposited in a superheated liquid. The group at Pacific Northwest National Lab (PNNL) working on the PICO project seeks to develop improvements to the project’s …

Ultra-Fast X-Ray Diffraction Of Metastable Structures During Hydrogen Crystallization, Andrew Pham

STAR Program Research Presentations

Big discoveries can come from small element, and hydrogen is the simplest element in the universe, but its property has been intensely studied in recent years. Hydrogen has a notably complex phase diagram, and its application is important to many scientific fields, such as fundamental physics, inertial confinement fusion, planetary sciences, etc. While sophisticated static observations have probed its structure at extremely high pressures, the higher-temperature studies applying dynamic compression is confined to optical measurement methods. In this project over the summer, I will present spectrally resolved x-ray scattering assessment from plasmons in dynamic compressed deuterium. Collaborating Compton scattering and …

Cuoricino Thermal Pulse Classification By Machine Learning Algorithms, Joshua Mann

Physics

Many of the various properties of neutrinos are still a mystery. One unknown is whether neutrinos are Majorana fermions or Dirac fermions. Cuoricino and CUORE are experiments that aim to solve this mystery. Noise reduction in these experiments hinges on the ability to discern among alpha, beta and gamma particle detections using the thermal pulses they create. In this paper, we look at Cuoricino data and attempt to classify pulses, not as alpha, beta or gamma particles, but rather as signal, noise or calibration data. We will use this preliminary testing ground to examine various machine learning algorithms' abilities in …

Improvements For The T0c+ Geometry Of The Fast Interaction Trigger (Fit) Upgrade To Alice At The Cern Lhc, Noah Miller

Physics

The purpose of the ALICE experiment at CERN is to investigate the properties of the strongly interacting quark-gluon plasma formed in the high-energy collisions of lead nuclei in the CERN Large Hadron Collider. ALICE has been collecting data since 2009. The upcoming upgrade of the CERN LHC injectors during 2019-20 will boost the luminosity and the collision rate beyond the design parameters for several of the key ALICE detectors including the forward trigger detectors. The new Fast Interaction Trigger (FIT) will enable ALICE to discriminate beam-beam interactions with a 99% efficiency for the collisions generated by the LHC at a …

Measurement And Modeling Of Cosmic Ray Exposure For Supercdms Dark Matter Detectors., Kameron Mccall, John Orrell, Jared Yamaoka

STAR Program Research Presentations

Dark matter is an unknown type of matter that composes roughly 27% of the observable universe and, as cosmological structure models suggest, the earth should be passing through a “dark halo” of this unknown matter present in the Milky Way galaxy. As we pass through this halo, the Super Cryogenic Dark Matter Search (SuperCDMS) experiment aims to directly detect dark -matter particles. Though many dark matter particle candidates exist, SuperCDMS focuses on the detection of particles called WIMPS (weakly interacting massive particles) as predicted by super-symmetric theories beyond the standard model. Due to the high-sensitivity of the germanium detectors employed, …

Cuore Image Analysis And Cuore-0 Shifting: A Contribution To The Search For Neutrinoless Double Beta Decay, Dakota Christopher Rose

Physics

In an effort to aid in the work of the Cryogenic Underground Observatory of Rare Events (CUORE) in moving towards confirming the existence of Neutrinoless Double Beta Decay, a six week trip was made to Assergi, Italy to work as an Onsite Shifter for the previous generation of the experiment, CUORE-0, as well as to aid in construction of the full CUORE detector. Furthermore, to help in understanding possible sources of experimental error, work was done analyzing images taken of the glue spots on the faces of each Tellurium Oxide detector crystals (also containing the source of the decay, Tellurium-130). …

Contributions To The Cuore Collaboration, Samuel Joseph Meijer

Physics

This paper describes work done between 2010 and 2013 to contribute to the CUORE collaboration, a physics collaboration searching for neutrinoless double-beta decay in tellurium. Measurement of this decay would indicate fundamental information about the nature of the neutrino. The implementation of a parylene-coated detector frame is described. Also, a temperature stabilization system for an automated gluing system was constructed. An image recognition algorithm is described for locating spots of glue and evaluating their acceptability.

Contributions To Background Reduction And Computer Simulations For Cuore & Cuore-0, Ivo J. Plamenac

Physics

CUORE and CUORE-0 aim to observe neutrinoless double beta decay in ¹³⁰Te; observing such this particular decay would substantiate the Majorana model for the neutrino and expand our current understanding of particle physics. This report will provide an overview of the Standard Model, our current framework for particle interactions, as well as the technical details of the CUORE experiment. Over the summers of 2010 and 2011, I contributed to the efforts of the CUORE collaboration by assisting in aspects such as background reduction, and explored detector behavior using computer simulations.

Building An Alpha Spectrometer For The Cuore Collaboration, David J. Miller

Physics

This paper will give the reader a brief introduction to the Standard Model, Neutrinoless Double Beta Decay (0νββ), and the CUORE experiment under construction at Gran Sasso National Lab in Assergi, Italy. The remainder of the paper will describe the process of creating a working alpha spectrometry system using silicon detectors and NIM and CAMAC electronics. Extensive details of the troubleshooting and calibration period are presented as a way for the reader to better understand the concepts involved in alpha spectroscopy and to not repeat mistakes made in this development process.

The Search For Charged Massive Supersymmetric Particles At The Lhc, Aleksey Pavlov

Physics

Charged Massive Particles (CHAMPs) are predicted in the Supersymmetry (SUSY) extension of the Standard Model though they have never been ob- served. We look for CHAMPs in the ALICE Detector at the Large Hadron Collider at CERN. While the main purpose of ALICE is to study Quark- Gluon Plasma, we take advantage of the tracking and time of flight capabilities of several sub-detectors in ALICE to look for signs of CHAMPs. These elusive particles are characterized by their slow velocity, high transverse momentum and therefore heavy mass. Our research found a small handful of candidates among a large sample size …

Could Alice Find The Elusive Higgs?, Tyler Williams

Physics

The Higgs boson is the theoretical mechanism for creating the mass of particles.  Although it has never been seen, the CERN Large Hadron Collider (LHC) is the most likely place for it to be created in the laboratory.  The ALICE (A Large Ion Collider Experiment) detector is focused on the study of heavy ion collisions at the LHC and was not designed to find the Higgs boson; however, there is a chance it could be detected there. Although the luminosity (collision rate) for PbPb collisions is much lower than that for pp collisions, PbPb collisions have a higher probability to …

Contributing Efforts In The Search For Neutrinoless Double Beta Decay, Laura Christine Sparks

Physics

Cryogenic Underground Observatory for Rare Events (CUORE) will be part of the next generation of detectors used to search for neutrinoless double beta decay (0νββ). Located in Assergi, Italy at the Gran Sasso National Laboratory (LNGS), CUORE will be a large cryogenic bolometer composed of 988 tellurium dioxide (TeO2) detectors with a total mass of 750 kg, and will search for 0νββ in 130Te. As the experiment will monitor the extremely rare event of 0νββ, all factors contributing to background need to be minimized to effectively increase the sensitivity. I assisted the LNGS researchers over the summer of 2008 by …