Elementary Particles and Fields and String Theory Commons^™

One-Loop Corrections To Dihadron Production In Dis At Small X, Filip Bergabo

Dissertations, Theses, and Capstone Projects

We calculate the one-loop corrections to dihadron production in Deep Inelastic Scattering (DIS) at small x using the Color Glass Condensate formalism. We show that all UV and soft singularities cancel while the collinear divergences are absorbed into quark and anti quark-hadron fragmentation functions. Rapidity divergences lead to JIMWLK evolution of dipoles and quadrupoles describing multiple-scatterings of the quark anti-quark dipole on the target proton/nucleus. The resulting cross section is finite and can be used for phenomenological studies of dihadron angular correlations at small x in a future Electron-Ion Collider (EIC).

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 …

A Multidimensional Study Of The Structure Function Ratio Σlt'/ Σ₀ From Hard Exclusive 𝜋⁺ Electro-Production Off Protons In The Gpd Regime, S. Diehl, A. Kim, K. Joo, P. Achenbach, Z. Akbar, M. J. Amaryan, H. Atac, H. Avagyan, C. Ayerbe Gayoso, L. Baashen, L. Barion, M. Bashkanov, M. Battaglieri, I. Bedlinsky, B. Benkel, F. Benmokhtar, A. Bianconi, A. S. Biselli, M. Bondi, W.A. Booth, M. Zurek, Et Al.

Physics Faculty Publications

A multidimensional extraction of the structure function ratio from the hard exclusive ^→ep → e'n𝜋+ reaction above the resonance region has been performed. The study was done based on beam-spin asymmetry measurements using a 10.6 GeV incident electron beam on a liquid-hydrogen target and the CLAS12 spectrometer at Jefferson Lab. The measurements focus on the very forward regime (t/Q²≪ 1) with a wide kinematic range of in the valence regime (0.17 < 𝓍_B < 0.55), and virtualities ranging from 1.5 GeV² up to 6 GeV². The results and their comparison to theoretical models based on Generalized Parton Distributions demonstrate the sensitivity to chiral-odd …

Determination Of The Titanium Spectral Function From (E, E'P) Data, L. Jiang, A.M. Ankowski, D. Abrams, L. Gu, B. Aljawrneh, S. Alsalmi, J. Bane, A. Batz, S. Barcus, M. Barroso, V. Bellini, O. Benhar, J. Bericic, D. Biswas, A. Camsonne, J. Castellanos, J. -P. Chen, M. E. Christy, K. Craycraft, R. Cruz-Torres, H. Dai, D. Day, A. Dirican, S. -C. Dusa, E. Fuchey, T. Gautam, C. Giusti, J. Gomez, C. Gu, T. J. Hague, J. -O. Hansen, F. Hauenstein, D. W. Higinbotham, C. Hyde, Z. Jerzyk, A. M. Johnson, C. Keppel, C. Lanham, S. Li, R. Lindgren, H. Liu, C. Mariani, R. E. Mcclellan, D. Meekins, R. Michaels, M. Mihovilovic, M. Murphy, D. Nguyen, M. Nycz, L. Ou, B. Pandey, V. Pandey, K. Park, G. Perera, A.J.R. Puckett, S.N. Santiesteban, S. Ŝirca, T. Su, L. Tang, Y. Tian, N. Ton, B. Wojsekhowski, S. Wood, Z. Ye, J. Zhang

Physics Faculty Publications

The E12-14-012 experiment, performed in Jefferson Lab Hall A, has measured the (e,e′p) cross section in parallel kinematics using a natural titanium target. In this paper, we report the analysis of the dataset obtained in different kinematics for our solid natural titanium target. Data were obtained in a range of missing momentum and missing energy between 15 ≲ p_m ≲ 250  MeV/c and 12 ≲ Em ≲ 80  MeV, respectively, and using an electron beam energy of 2.2 GeV. We measured the reduced cross section with ∼7% accuracy as a function of both missing momentum and missing energy. …

Gluon Transverse-Momentum-Dependent Distributions From Large-Momentum Effective Theory, Ruilin Zhu, Yao Ji, Jian-Hui Zhang, Shuai Zhao

Physics Faculty Publications

We demonstrate that gluon transverse-momentum-dependent parton distribution functions (TMDPDFs) can be extracted from lattice calculations of appropriate Euclidean correlations in large-momentum effective theory (LaMET). Based on perturbative calculations of gluon unpolarized and helicity TMDPDFs, we present a matching formula connecting them and their LaMET counterparts, where the latter are renormalized in a scheme facilitating lattice calculations and converted to the MS ¯ scheme. The hard matching kernel is given up to one-loop level. We also show that the perturbative result is independent of the prescription used for the pinch-pole singularity in the relevant correlations. Our results offer a guidance for …

Observation Of Correlations Between Spin And Transverse Momenta In Back-To-Back Dihadron Production At Clas12, H. Avakian, T.B. Hayward, A. Kotzinian, W.R. Armstrong, H. Atac, C. Ayerbe Gayoso, L. Baashen, N.A. Balzell, L. Barion, M. Bashkanov, M. Battaglieri, I. Bedlinskiy, B. Benkel, F. Benmokhtar, A. Bianconi, L. Biondo, A. S. Biselli, M. Bondi, S. Boiarinov, M. Zurek, Et Al.

Physics Faculty Publications

We report the first measurements of deep inelastic scattering spin-dependent azimuthal asymmetries in back-to-back dihadron electroproduction in the deep inelastic scattering process. In this reaction, two hadrons are produced in opposite hemispheres along the z axis in the virtual photon-target nucleon center-of-mass frame, with the first hadron produced in the current-fragmentation region and the second in the target-fragmentation region. The data were taken with longitudinally polarized electron beams of 10.2 and 10.6 GeV incident on an unpolarized liquid-hydrogen target using the CLAS12 spectrometer at Jefferson Lab. Observed nonzero sinΔϕ modulations in ep→e'pπ⁺ X events, where Δϕ is the difference …

Prospects For 𝛾*𝛾* → 𝜋𝜋 Via Lattice Qcd, Raúl Briceño, Andrew W. Jackura, Arkaitz Rodas, Juan V. Guerrero

Physics Faculty Publications

The 𝛾*𝛾* → 𝜋𝜋 scattering amplitude plays a key role in a wide range of phenomena, including understanding the inner structure of scalar resonances as well as constraining the hadronic contributions to the anomalous magnetic moment of the muon. In this work, we explain how the infinite-volume Minkowski amplitude can be constrained from finite-volume Euclidean correlation functions. The relationship between the finite-volume Euclidean correlation functions and the desired amplitude holds up to energies where 3𝜋 states can go on shell, and is exact up to exponentially small corrections that scale like 𝒪(e^−m𝜋L), where L is the spatial extent …

Exclusive 𝝅⁻ Electroproduction Off The Neutron In Deuterium In The Resonance Region, Y. Tian, R. W. Gothe, V. I. Mokeev, G. Hollis, M. J. Amaryan, W. R. Armstrong, H. Atac, H. Avakian, L. Barion, M. Battaglieri, I. Bedlinskiy, B. Benkel, F. Benmokhtar, A. Bianconi, L. Biondo, A. Biselli, F. Bossù, S. Boiarinov, M. Bondì, J. Zhang, Et Al., The Clas Collaboration

Physics Faculty Publications

New results for the exclusive and quasifree cross sections off neutrons bound in deuterium 𝛾_vn(p) → pπ− (p) are presented over a wide final state hadron angle range with a kinematic coverage of the invariant mass (W) up to 1.825 GeV and the four-momentum transfer squared (Q²) from 0.4 to 1.0 GeV². The exclusive structure functions were extracted and their Legendre moments were obtained. Final-state-interaction contributions have been kinematically separated from the extracted quasifree cross sections off bound neutrons solely based on the analysis of the experimental data. These new results will serve as …

Fourier Acceleration In The Linear Sigma Model, Cameron Cianci

Honors Scholar Theses

The linear sigma model is a low energy effective model of Quantum Chromodynamics. This model mimics the breaking of chiral symmetry both spontaneously and explicitly through the quark condensate and pion mass matrix respectively. Fourier acceleration is a method that can be implemented in the Hybrid Monte-Carlo algorithm which decreases autocorrelations due to critical slowing down through tuning the mass parameters in the HMC algorithm. Fourier acceleration is applied to the linear sigma model with a novel mass estimation procedure, by assuming the modes behave approximately like simple harmonic oscillators. The masses are chosen by sampling the expectation values of …

Generation Of Phase Transitions Boundaries Via Convolutional Neural Networks, Christopher Alexis Ibarra

Open Access Theses & Dissertations

Accurate mapping of phase transitions boundaries is crucial in accurately modeling the equation of state of materials. The phase transitions can be structural (solid-solid) driven by temperature or pressure or a phase change like melting which defines the solid-liquid melt line. There exist many computational methods for evaluating the phase diagram at a particular point in temperature (T) and pressure (P). Most of these methods involve evaluation of a single (P,T) point at a time. The present work partially automates the search for phase boundaries lines utilizing a machine learning method based on convolutional neural networks and an efficient search …

Dual Energy Electron Storage Ring Cooler Design For Relativistic Ion Beams, Bhawin Dhital

Physics Theses & Dissertations

Collider experiments demand small beam emittances in order to achieve high luminosity. For light particles such as electrons, there exists a natural synchrotron radiation damping resulting in low emittance beams at equilibrium. In the case of heavy particle beams such as proton or ion beams, there is no significant synchrotron radiation damping effect and some cooling mechanism is needed to get to low emittance beams. A dual energy storage ring cooler is a novel concept proposed to cool hadron beams at higher energies. The design consists of two rings: a low energy ring and a high energy ring connected by …

Physics 516: Electromagnetic Phenomena (Spring 2023), Philip C. Nelson

Department of Physics Papers

These course notes are made publicly available in the hope that they will be useful. All reports of errata will be gratefully received. I will also be glad to hear from anyone who reads them, whether or not you find errors: pcn@upenn.edu.

A Mode-Sum Prescription For The Renormalized Stress Energy Tensor On Black Hole Spacetimes, Peter Taylor, Cormac Breen, Adrian Ottewill

Articles

In this paper, we describe an extremely efficient method for computing the renormalized stress-energy tensor of a quantum scalar field in spherically symmetric black hole spacetimes. The method applies to a scalar field with arbitrary field parameters. We demonstrate the utility of the method by computing the renormalized stress-energy tensor for a scalar field in the Schwarzschild black hole spacetime, applying our results to discuss the null energy condition and the semiclassical backreaction.

Classification Of Pixel Tracks To Improve Track Reconstruction From Proton-Proton Collisions, Kebur Fantahun, Jobin Joseph, Halle Purdom, Nibhrat Lohia

SMU Data Science Review

In this paper, machine learning techniques are used to reconstruct particle collision pathways. CERN (Conseil européen pour la recherche nucléaire) uses a massive underground particle collider, called the Large Hadron Collider or LHC, to produce particle collisions at extremely high speeds. There are several layers of detectors in the collider that track the pathways of particles as they collide. The data produced from collisions contains an extraneous amount of background noise, i.e., decays from known particle collisions produce fake signal. Particularly, in the first layer of the detector, the pixel tracker, there is an overwhelming amount of background noise that …

Search For A W' Boson Decaying To A Vector-Like Quark And A Top Or Bottom Quark In The All-Jets Final State At √S = 13 Tev, The Cms Collaboration

Faculty Publications, Department of Physics and Astronomy

A search is presented for a heavy W0 boson resonance decaying to a B or T vector-like quark and a t or a b quark, respectively. The analysis is performed using protonproton collisions collected with the CMS detector at the LHC. The data correspond to an integrated luminosity of 138 fb⁻¹ at a center-of-mass energy of 13TeV. Both decay channels result in a signature with a t quark, a Higgs or Z boson, and a b quark, each produced with a significant Lorentz boost. The all-hadronic decays of the Higgs or Z boson and of the t quark are …

Magnetic Field Effects On The Physics Of Neutron Stars, Aric A. Hackebill

Dissertations, Theses, and Capstone Projects

In the context of neutron stars (NS), dense-magnetized quark and hadron models have been well studied under the assumption that the system's pressures are isotropic. However, the pressures determined from semi-classical statistical averaging of the energy momentum tensor in the presence of a uniform background magnetic field are anisotropic with different pressures arising along and perpendicular to the magnetic field direction. Since large magnetic fields are expected to be present in the interior of NS, it is important to understand the roll the pressure anisotropy plays. While considering the pressure anisotropy, we revisit some important calculations in NS physics.

We …

The Separation Of Charm And Bottom Decays Measured In P+Au Collisions At 200 Gev, Zhiyan Wang

Dissertations, Theses, and Capstone Projects

It has long been observed experimentally, from previous heavy-flavor electron measurements, that heavy quarks are subject to substantial modifications of their momentum spectrum. Using the PHENIX detector at the Relativistic Heavy Ion Collider (RHIC), measurements of the production of open heavy flavor hadrons with charm and bottom quarks in p+Au collisions at 200 GeV are studied and presented in this thesis. Distance of closest approach analysis of electron tracks is used to study the semileptonic decay electrons from charm and bottom hadrons. The results include invariant yield and fraction of bottom electrons. In addition to the p+p and Au+Au collisions’ …

Astrophysics, Cosmology And Particle Phenomenology At The Energy Frontier, Jorge Fernandez Soriano

Dissertations, Theses, and Capstone Projects

This dissertation consists of two parts, treating significantly separated fields. Each part consists on several chapters, each treating a somewhat isolated topic from the rest. In each chapter, I present some of the work developed during my passage through the graduate program, which has mostly been published elsewhere.

Part I – Cosmic Rays and Particle Physics

• Chapter 1: In this chapter we present an introduction to the topic of cosmic ray physics, with an special focus on the so-called ultra high energy cosmic rays: their potential origins, effects during their propagation between their sources and Earth, the different techniques used …

Plasmonic Nanomaterials-Based Point-Of-Care Biosensors, Rohit Gupta

McKelvey School of Engineering Theses & Dissertations

Point-of-care (POC) biosensors, although rapid and easy-to-use, are orders magnitude less sensitive than laboratory-based tests. Further they are plagued by poor stability of recognition element thus limiting its widespread applicability in resource-limited settings. Therefore, there is a critical need for realizing stable POC biosensors with sensitivity comparable to gold-standard laboratory-based tests. This challenge constitutes the fundamental basis of this dissertation work– to expand access to quality and accurate biodiagnostic tools. At the heart of these solutions lies plasmonic nanoparticles which exhibit unique optical properties which are attractive for label-free and labelled biosensors.Firstly, we improve the stability and applicability of label-free …

Qcd Corrections In Tqγ Production At Hadron Colliders, Nikolaos Kidonakis, Nodoka Yamanaka

Faculty Publications

We study QCD corrections for the associated production of a single top quark and a photon (tqγ production) at hadron colliders. We calculate the NLO cross section at LHC and future collider energies for a variety of kinematical cuts, and we estimate uncertainties from scale dependence and from parton distributions. We also calculate differential distributions in top-quark transverse-momentum and rapidity as well as photon energy. Finally, we study higher-order corrections from soft-gluon emission for this process, and we provide approximate NNLO (aNNLO) results for the cross section and top-quark differential distributions. We also compare our calculations with recent measurements from …