Elementary Particles and Fields and String Theory Commons^™

Renormalized Stress-Energy Tensor For Scalar Fields In Hartle-Hawking, Boulware, And Unruh States In The Reissner-Nordström Spacetime, Julio Arrechea, Cormac Breen, Adrian Ottewill, Peter Taylor

Articles

In this paper, we consider a quantum scalar field propagating on the Reissner-Nordström black hole spacetime. We compute the renormalized stress-energy tensor for the field in the Hartle-Hawking, Boulware and Unruh states. When the field is in the Hartle-Hawking state, we renormalize using the recently developed “extended coordinate” prescription. This method, which relies on Euclidean techniques, is very fast and accurate. Once, we have renormalized in the Hartle-Hawking state, we compute the stress-energy tensor in the Boulware and Unruh states by leveraging the fact that the difference between stress-energy tensors in different quantum states is already finite. We consider a …

K-Long Identification Efficiency Of The Klm Detector In The Belle Ii Experiment Using Splot, Andrew J. Davis, Diptaparna Biswas, Swagato Banerjee

The Cardinal Edge

Long-lived neutral kaon mesons (neutral K-longs) are identified by energy deposits in the KLM detector of the Belle II experiment. However, various other particles can also deposit energy in the KLM detector. A statistical method known as sPlot can be utilized to distinguish between the energy deposit patterns of neutral K-longs vs. other backgrounds. This technique, currently developed with Monte-Carlo events, allows for a more robust determination of K-long identification efficiency in the KLM detector, which can eventually be applied on real data.

A Search For Decays Of The Higgs Boson To Invisible Particles In Events With A Top-Antitop Quark Pair Or A Vector Boson In Proton-Proton Collisions At √S = 13 Tev, Armen R. Tumasyan

Department of Physics and Astronomy: Faculty Publications

The first search for nonresonant production of Higgs boson pairs (HH) with one H decaying into four leptons and the other into a pair of b quarks is presented, using proton-proton collisions recorded at a center-of-mass energy of √s = 13 TeV by the CMS experiment. The analyzed data correspond to an integrated luminosity of 138 fb⁻¹. A 95% confidence level upper limit of 32.4 is set on the signal strength modifier μ, defined as the ratio of the observed HH production rate in the HH → ZZ*bb → 4ℓbb decay channel to the standard model …

Study Of Microphonic Effects On The C100 Cryomodule For High Energy Electron Beam Accelerators, Caleb James Hull

Mechanical & Aerospace Engineering Theses & Dissertations

The Continuous Electron Beam Accelerator Facility (CEBAF) at Thomas Jefferson National Laboratory (JLab) is a particle accelerator which can accelerate an electron beam to relativistic speeds and apply the beam onto target samples. The C100 superconducting radio frequency (SRF) cavity is the primary accelerating structure of the C100 cryomodule, one of the many cryomodules which compose the CEBAF linear accelerator. SRF cavities are particularly sensitive to internal and external vibrations that can result in a phenomenon called microphonics which degrade the operational stability of a cryomodule.

The purpose of this thesis is to investigate the significance of mechanical disturbances on …

Inverse Mappers For Qcd Global Analysis, Manal Almaeen

Computer Science Theses & Dissertations

Inverse problems – using measured observations to determine unknown parameters – are well motivated but challenging in many scientific problems. Mapping parameters to observables is a well-posed problem with unique solutions, and therefore can be solved with differential equations or linear algebra solvers. However, the inverse problem requires backward mapping from observable to parameter space, which is often nonunique. Consequently, solving inverse problems is ill-posed and a far more challenging computational problem.

Our motivated application in this dissertation is the inverse problems in nuclear physics that characterize the internal structure of the hadrons. We first present a machine learning framework …

Deep Virtual Pion Pair Production, Dilini Lakshani Bulumulla

Physics Theses & Dissertations

This experiment investigates the deep virtual production of both σ− and ρ− mesons, with a particular focus on the microscopic structure of the σ mesons. While the ρ meson is an ordinary qq¯ pair, the σ meson is composed of not only the typical qq¯ pair, making it a topic of controversy for nearly six decades. Although the existence of the σ− meson is now well established, its microscopic structure remains poorly understood. The primary objective of this thesis is to contribute to the understanding of the σ meson by analyzing its deep virtual production. The main focus of this …

Search For Higgs Boson Pair Production In The Multiple Lepton Final State Using Proton-Proton Collision Data At √S =13 Tev From The Atlas Detector, Santosh Parajuli

Physics Theses and Dissertations

In this thesis, a search is presented for the production of Higgs boson pairs in final states containing three light leptons (e/mu). The analysis utilizes data collected by the ATLAS detector at the Large Hadron Collider from proton-proton (pp) collisions at a center-of-mass energy of √s=13 TeV, corresponding to an integrated luminosity of 140 fb-1. The investigation aims to identify any significant deviations from the expected background levels defined by the Standard Model. The Higgs boson, as the cornerstone of the electroweak symmetry breaking mechanism, plays a crucial role in our understanding of particle physics. Studying the production of Higgs …

A Statistical Framework For Automating Resonance Detection: Modelling Pion Proton Collision Activity, Shahnaz Abdul Hameed

2023 REYES Proceedings

In this paper, we analyze π− − p elastic collision data from the Particle Data Group (PDG), by creating a general framework to study resonance activity: automating peak detection, extrapolating, parametrizing thresholds, filtering resonances and further comparing and extracting characteristics, to identify Delta (Δ) baryons. We then analyse experimental Energy vs Phase-Shift (δ) data for the collision π+ +π− → π− +π+, model the T matrix from a curve fitted polynomial representation of the K⁻¹ matrix, simulate its Riemann sheets and analyse it to identify the characteristics of ρ⁰(770) meson, as well as estimate their uncertainties. …

Modified Geometries, Clifford Algebras And Graphs: Their Impact On Discreteness, Locality And Symmetr, Roman Sverdlov

Mathematics & Statistics ETDs

In this dissertation I will explore the question whether various entities commonly used in quantum field theory can be “constructed". In particular, can spacetime be “constructed" out of building blocks, and can Berezin integral be “constructed" in terms of Riemann integrals.

As far as “constructing" spacetime out of building blocks, it has been attempted by multiple scientific communities and various models were proposed. But the common downfall is they break the principles of relativity. I will explore the ways of doing so in such a way that principles of relativity are respected. One of my approaches is to replace points …

Fractional Charge Concept Opened Gates For New Ideas On Composition Of Matter, Polievkt Perov

College of Arts & Sciences Faculty Works

Before the concept of quarks with fractional electric charges was introduced, the electron charge magnitude e was considered as the smallest amount of charge in nature so the charge of any object could be only an integer number of ± e. Then it was suggested that the proton and neutrons are composed of quarks with the fractional charges, combined in such a way that the total charge of a proton occurred to be that same known charge +e, and the charge of a neutron was zero. We suggest expanding that fruitful concept of fractional charges to build structural models of …

Search For Nonresonant Higgs Boson Pair Production In The Four Leptons Plus Twob Jets Final State In Proton-Proton Collisions At √S = 13 Tev, Armen R. Tumasyan, Cma Collaboration

Department of Physics and Astronomy: Faculty Publications

The first search for nonresonant production of Higgs boson pairs (HH) with one H decaying into four leptons and the other into a pair of b quarks is presented, using proton-proton collisions recorded at a center-of-mass energy of √s = 13 TeV by the CMS experiment. The analyzed data correspond to an integrated luminosity of 138 fb⁻¹. A 95% confidence level upper limit of 32.4 is set on the signal strength modifier μ, defined as the ratio of the observed HH production rate in the HH ⟶ ZZ*bb[bar] ⟶ 4ℓb[bar] decay channel to the standard model (SM) …

Cosmological Vector Fields And Constraining The Neutrino Masses, Avery J. Tishue

Dartmouth College Ph.D Dissertations

In this thesis I explore two main topics: the role and consequences of cosmological vector fields, and new ideas for constraining fundamental physics with state-of-the-art experiments. These topics are disparate in content and technique but unified in their attempt to leverage novel approaches to better understand longstanding questions in cosmology. These questions, such as ``What is causing the universe to accelerate today?'' and ``What are the neutrino masses?'', underpin the modern cosmological paradigm. They play a key role in our understanding of cosmic history, the formation of structure, and the fate of our universe. Answers to or hints about these …

Extension Of The Lux-Zeplin Nr Background To 600 Phd, Jackson Codd

Macalester Journal of Physics and Astronomy

In June 2022, the LUX-ZEPLIN collaboration released its first results, with the
most precise measurements of any direct dark matter detector. The findings were
calculated using the expected spin-independent WIMP-nucleon interaction model,
which would result in small energies deposited in the detector. Therefore, the
background of non-dark interactions was calculated for events with S1 areas up to
80 phd (Aalbers et al. 2022). In order to increase the sensitivity to high energy
WIMP-nucleon interaction events, as predicted by other models, we extended the
non-dark NR background to events with S1 areas of up to 600 phd. We found a
large …

A Study Of Data/Monte Carlo Agreement In Charmed Baryon Decays At Belle Ii, Kaitlyn Thurmond

Honors Theses

The Belle II experiment at the SuperKEKB electron-positron accelerator facility in Tsukuba, Japan has a primary goal of searching for new physics beyond the Standard Model of particle physics. Extremely precise measurements of particle decays will be compared with Standard Model predictions in order to expose the presence of new particles and interactions. These measurements are prepared using simulated samples to avoid potential biases when studying the data. The Belle II collaboration produces two types of simulated samples for this purpose. One is produced with consistent calibration payloads and another with payloads calibrated as a function of data taking. This …

An Analysis Of Detection Asymmetry Using Baryon Decays In Belle Ii, Matthew Mestayer

Honors Theses

The purpose of this study was to determine the detection asymmetry of the Belle II detector using decays of two common baryons, Λ⁰ → ��π^- and Σ⁺ → ��π⁰. A Monte Carlo simulation of both decays was used to determine the validity of signal isolation criteria. These criteria were then applied to the Belle II data, allowing for a comparison of the detection asymmetry in the data relative to the simulation. The results show a moderate detection asymmetry when using the Λ⁰ → ��π^- decay, particularly for forward-going baryons. For the Σ^{+ …}

Electron And Other Quarks As Particles Made Of Elementary Particles Of Charge E/3 And Mass Me/6, Polievkt Perov

College of Arts & Sciences Faculty Works

We suggest that the first-generation quarks are not elementary particles, but structures made of a basic elementary particle of charge e/3 and its antiparticle, interacting via an electrostatic force. The structures are suggested for d-quark as consisting of one positive and two negative basic elementary charges, for u-quark as a structure with one negative and three positive basic charges, for an electron as a quark with one positive and four negative basic charges, and for one more quark made of one positive and one negative basic charge. All the suggested structures are in a spinning motion and are stable. The …

Study Of Missing Mass Background In The Clas12 Detector, Jessie Hess, Gerard P. Gilfoyle, Lamya Baashen

Honors Theses

At Jefferson Lab we use the CLAS12 detector to measure the neutron magnetic form factor. An accurate measurement of the CLAS12 neutron detection efficiency (NDE) is required. We use the nuclear reaction ���� → ��′��+�� as a source of tagged neutrons and obtain the NDE from the ratio of expected neutrons to detected ones. We assume the final state consists of ��′��+�� only, use the ��′��+ information to predict the neutron's position(expected) and then search for that neutron(detected). We select neutrons with the missing mass (MM) technique. We use simulation to validate our methods. We simulated events with the Monte-Carlo …

New Physics In The Age Of Precision Cosmology, Vivian I. Sabla

Dartmouth College Ph.D Dissertations

The Lambda-cold dark matter (LCDM) model has become the standard model of cosmology because of its ability to reproduce a vast array of cosmological observations, from the earliest moments of our Universe, to the current period of accelerated expansion, which it does with great accuracy. However, the success of this model only distracts from its inherent flaws and ambiguities. LCDM is purely phenomenological, providing no physical explanation for the nature of dark matter, responsible for the formation and evolution of large-scale structure, and giving an inconclusive explanation for dark energy, which drives the current period of accelerated expansion.

Furthermore, cracks …

K-Long Identification Efficiency Of The Klm Detector In The Belle Ii Experiment Using Splot, Jackson Davis, Diptaparna Biswas, Swagato Banerjee

Undergraduate Research Events

Long-lived neutral kaon mesons (K^0_L) are identified by energy deposits in the KLM detector of the Belle II experiment. However, various other particles can also deposit energy in the KLM detector. A statistical method known as sP lot can be utilized to distinguish between the energy deposit patterns of K0 L vs other backgrounds. This technique, currently developed with Monte-Carlo events, allows for a more robust determination of K0 L identification efficiency in the KLM detector, which can eventually be applied on real data

Beam-Based Target Alignment For Mu2e, Helenka Casler

Dissertations, Theses, and Capstone Projects

The Mu2e Experiment is a precision experiment at Fermi National Accelerator Laboratory, searching for charged lepton flavor violation (CLFV) in the conversion of a muon to an electron in the presence of an atomic nucleus. In order to achieve the expected single-event sensitivity of 3 × 10^-17 , Mu2e will require an intense muon beam, generated via pion decay. These pions are the product of a proton beam striking a radiatively-cooled tungsten target. In order to maximize pion production and prevent target failure, the beam will have to be aligned with the target center to within 0.5 mm. The …