# Elementary Particles and Fields and String Theory Commons™

## All Articles in Elementary Particles and Fields and String Theory

985 full-text articles. Page 5 of 40.

Accessing Scattering Amplitudes Using Quantum Computers, 2022 Old Dominion University

#### Accessing Scattering Amplitudes Using Quantum Computers, Raúl A. Briceño, Marco A. Carrillo, Juan V. Guerrero, Maxwell T. Hansen, Alexandru M. Sturzu

##### Physics Faculty Publications

Future quantum computers may serve as a tool to access non-perturbative real-time correlation functions. In this talk, we discuss the prospects of using these to study Compton scattering for arbitrary kinematics. The restriction to a finite-volume spacetime, unavoidable in foreseeable quantum-computer simulations, must be taken into account in the formalism for extracting scattering observables. One approach is to work with a non-zero iϵ-prescription in the Fourier transform to definite momentum and then to estimate an ordered double limit, in which the spacetime volume is sent to infinity before ϵ is sent to 0. For the amplitudes and parameters considered here, …

Cooling Performance In A Dual Energy Storage Ring Cooler, 2022 Old Dominion University

#### Cooling Performance In A Dual Energy Storage Ring Cooler, B. Dhital, Y. S. Derbenev, D. Douglas, G. A. Krafft, H. Zhang, F. Lin, V. S. Morozov, Y. Zhang, Frank Zimmerman (Ed.), Porntip Sudmuang (Ed.), Prapong Klysubun (Ed.), Prapaiwan Sunwong (Ed.), Thakonwat Chanwattana (Ed.), Christine Petit-Jean-Genaz (Ed.), Volker R.W. Schaa (Ed.)

##### Physics Faculty Publications

The longitudinal and transverse emittance growth in hadron beams due to intra-beam scattering (IBS) and other heating sources deteriorate the luminosity in a collider. Hence, a strong hadron beam cooling is required to reduce and preserve the emittance. The cooling of high energy hadron beam is challenging. We propose a dual energy storage ring-based electron cooler that uses an electron beam to extract heat away from hadron beam in the cooler ring while the electron beam is cooled by synchrotron radiation damping in the high energy damping ring. In this paper, we present a design of a dual energy storage …

Quark Spin-Orbit Correlations In The Proton, 2022 Old Dominion University

#### Quark Spin-Orbit Correlations In The Proton, M. Engelhardt, J. Green, N. Hasan, T. Izubuchi, C. Kallidonis, S. Krieg, S. Liuti, S. Meinel, J. Negele, A. Pochinsky, A. Rajan, G. Silvi, S. Syritsyn

##### Physics Faculty Publications

Generalized transverse momentum-dependent parton distributions (GTMDs) provide a comprehensive framework for imaging the internal structure of the proton. In particular, by encoding the simultaneous distribution of quark transverse positions and momenta, they allow one to directly access longitudinal quark orbital angular momentum, and, moreover, to correlate it with the quark helicity. The relevant GTMD is evaluated through a lattice calculation of a proton matrix element of a quark bilocal operator (the separation in which is Fourier conjugate to the quark momentum) featuring a momentum transfer (which is Fourier conjugate to the quark position), as well as the Dirac structure appropriate …

Connecting Matrix Elements To Multi-Hadron Form-Factors, 2022 Old Dominion University

#### Connecting Matrix Elements To Multi-Hadron Form-Factors, Andrew W. Jackura

##### Physics Faculty Publications

We discuss developments in calculating multi-hadron form-factors and transition processes via lattice QCD. Our primary tools are finite-volume scaling relations, which map spectra and matrix elements to the corresponding multi-hadron infinite-volume amplitudes. We focus on two hadron processes probed by an external current, and provide various checks on the finite-volume formalism in the limiting cases of perturbative interactions and systems forming a bound state. By studying model-independent properties of the infinite-volume amplitudes, we are able to rigorously define form-factors of resonances.

Existence And Non-Existence Of Doubly Heavy Tetraquark Bound States, 2022 Old Dominion University

#### Existence And Non-Existence Of Doubly Heavy Tetraquark Bound States, M. Pflaumer, Luka Leskovec, S. Meinel, M. Wagner

##### Physics Faculty Publications

In this work we investigate the existence of bound states for doubly heavy tetraquark systems Q¯Q¯′qq′ in a full lattice-QCD computation, where heavy bottom quarks are treated in the framework of non-relativistic QCD. We focus on three systems with quark content b¯b¯ud, b¯b¯us and b¯c¯ud. We show evidence for the existence of b¯b¯ud and b¯b¯us bound states, while no binding appears to be present for b¯c¯ud. For the bound four-quark states we also discuss the importance of various creation operators and give an estimate of the meson-meson and diquark-antidiquark percentages.

Perturbative Unitarity And Nec Violation In Genesis Cosmology, 2022 Old Dominion University

#### Perturbative Unitarity And Nec Violation In Genesis Cosmology, Yong Cai, Ji Xu, Shuai Zhao, Siyi Zhou

##### Physics Faculty Publications

Explorations of the violation of null energy condition (NEC) in cosmology could enrich our understanding of the very early universe and the related gravity theories. Although a fully stable NEC violation can be realized in the “beyond Horndeski” theory, it remains an open question whether a violation of the NEC is allowed by some fundamental properties of UV-complete theories or the consistency requirements of effective field theory (EFT). We investigate the tree-level perturbative unitarity for stable NEC violations in the contexts of both Galileon and “beyond Horndeski” genesis cosmology, in which the universe is asymptotically Minkowskian in the past. We …

Observation Of Azimuth-Dependent Suppression Of Hadron Pairs In Electron Scattering Off Nuclei, 2022 Old Dominion University

#### Observation Of Azimuth-Dependent Suppression Of Hadron Pairs In Electron Scattering Off Nuclei, S. J. Paul, S. Morán, M. Arratia, A. El Alaoui, H. Hakobyan, W. Brooks, M. J. Amaryan, W. R. Armstrong, H. Atac, L. Baashen, N. A. Baltzell, L. Barion, M. Bashkanov, M. Battaglieri, I. Bedlinskiy, B. Benkel, F. Benmokhtar, A. Bianconi, L. Biondo, A. S. Biselli, M. Bondi, F. Bossù, S. Boiarinov, K.-Th. Brinkmann, W. J. Briscoe, D. Bulumulla, V. D. Burkert, R. Capobianco, D. S. Carman, A. Celentano, V. Chesnokov, T. Chetry, G. Ciullo, P. L. Cole, M. Contalbrigo, G. Constantini, A. D' Angelo, N. Dashyan, R. De Vita, M. Defurne, A. Deur, S. Diehl, C. Dilks, C. Djalali, R. Dupre, H. Egiyan, L. El Fassi, P. Eugenio, S. Fegan, A. Filippi, G. Gavalian, Y. Ghandilyan, G. P. Gilfoyle, A. A. Golubenko, G. Gosta, R. W. Gothe, K. A. Griffioen, M. Guidal, M. Hattawy, T. B. Hayward, D. Heddle, A. Hobart, M. Holtrop, Y. Ilieva, D. G. Ireland, E. L. Isupov, H. S. Jo, R. Johnston, K. Joo, S. Joosten, D. Keller, A. Khanal, M. Khandaker, W. Kim, A. Kripko, V. Kubarovsky, V. Lagerquist, L. Lanza, M. Leali, S. Lee, P. Lenisa, X. Li, K. Livingston, I.J.D. Macgregor, D. Marchand, V. Mascagna, B. Mckinnon, Z. E. Meziani, S. Migliorati, R. G. Milner, T. Mineeva, M. Mirazita, V. I. Mokeev, P. Moran, C. Munoz Camacho, K. Neupane, D. Nguyen, S. Niccolai, G. Niculescu, M. Osipenko, A. I. Ostrovidov, P. Pandey, M. Paolone, L. L. Pappalardo, R. Paremuzyan, E. Pasyuk, W. Phelps, N. Pilleux, D. Pocanic, O. Pogorelko, M. Pokhrel, J. Poudel, J. W. Price, Y. Prok, B. A. Raue, T. Reed, M. Ripani, G. Rosner, F. Sabatié, C. Salgado, A. Schmidt, R. A. Schumacher, Y. G. Sharabian, E. V. Shirokov, U. Shrestha, P. Simmerling, D. Sokhan, N. Sparveris, S. Stepanyan, I. I. Strakovsky, S. Strauch, J. A. Tan, R. Tyson, M. Ungaro, S. Vallarino, L. Venturelli, H. Voskanyan, E. Voutier, X. Wei, R. Wishart, M. H. Wood, N. Zachariou, Z. W. Zhao, V. Ziegler, M. Zurek

##### Physics Faculty Publications

We present the first measurement of dihadron angular correlations in electron-nucleus scattering. The data were taken with the CLAS detector and a 5.0 GeV electron beam incident on deuterium, carbon, iron, and lead targets. Relative to deuterium, the nuclear yields of charged-pion pairs show a strong suppression for azimuthally opposite pairs, no suppression for azimuthally nearby pairs, and an enhancement of pairs with large invariant mass. These effects grow with increased nuclear size. The data are qualitatively described by the gibuu model, which suggests that hadrons form near the nuclear surface and undergo multiple scattering in nuclei. These results show …

Study Of ⋀N Fsi With ⋀ Quasi-Free Productions On The ³H (E, E'K⁺) X Reaction At Jlab, 2022 Old Dominion University

#### Study Of ⋀N Fsi With ⋀ Quasi-Free Productions On The ³H (E, E'K⁺) X Reaction At Jlab, K. Itabashi, K. N. Suzuki, B. Pandey, K. Okuyama, T. Gogami, S. Nagao, S. N. Nakamura, L. Tang, D. Abrams, T. Akiyama, D. Androic, K. Aniol, C. Ayerbe Gayoso, J. Bane, S. Barcus, J. Barrow, V. Bellini, H. Bhatt, D. Bhetuwal, D. Biswas, A. Camsonne, J. Castellanos, J.-P. Chen, J. Chen, S. Covrig, D. Chrisman, R. Cruz-Torres, R. Das, E. Fuchey, K. Gnanvo, F. Garibaldi, T. Gautam, J. Gomez, P. Gueye, T. J. Hague, O. Hansen, W. Henry, F. Hauenstein, D. W. Higinbotham, C. E. Hyde, M. Kaneta, C. Keppel, T. Kutz, N. Lashley-Colthirst, S. Li, H. Liu, J. Mammei, P. Markowitz, R. E. Mcclellan, F. Meddi, D. Meekins, R. Michaels, M. Milhovilovic, A. Moyer, D. Nguyen, M. Nycz, V. Owen, C. Palatchi, S. Park, T. Petkovic, S. Premathilake, P. E. Reimer, J. Reinhold, S. Riordan, V. Rodriguez, C. Samanta, S. N. Santiesteban, B. Sawatzky, S. Širca, K. Slifer, T. Su, Y. Tian, Y. Toyama, K. Uehara, G. M. Urciuoli, D. Votaw, J. Williamson, B. Wojtsekhowski, S. A. Wood, B. Yale, Z. Ye, J. Zhang, X. Zheng

##### Physics Faculty Publications

An nnΛ is a neutral baryon system with no charge. The study of the pure Λ-neutron system such as nnΛ gives us information on the Λn interaction. The nnΛ search experiment (E12-17-003) was performed at JLab Hall A in 2018. In this article, the Λn FSI was investigated by a shape analysis of the 3H(e, e′K+)X missing mass spectrum, and a preliminary result for the Λn FSI study is given.

Beam-Recoil Transferred Polarization In K+Y Electroproduction In The Nucleon Resonance Region With Clas12, 2022 Old Dominion University

#### Beam-Recoil Transferred Polarization In K+Y Electroproduction In The Nucleon Resonance Region With Clas12, D. S. Carman, A. D'Angelo, L. Lanza, V. I. Mokeev, K. P. Adhikari, M. J. Amaryan, W. R. Armstrong, H. Atac, H. Avakian, C. Ayerbe Gayoso, N. A. Baltzell, L. Barion, M. Battaglieri, I. Bedlinskiy, B. Benkel, A. Bianconi, A. S. Biselli, M. Bondi, S. Boiarinov, V. Ziegler

##### Physics Faculty Publications

Beam-recoil transferred polarizations for the exclusive electroproduction of K + Λ and K + Σ0 final states from an unpolarized proton target have been measured using the CLAS12 spectrometer at Jefferson Laboratory. The measurements at beam energies of 6.535 and 7.546 GeV span the range of four-momentum transfer Q2 from 0.3 to 4.5 GeV2 and invariant energy W from 1.6 to 2.4 GeV, while covering the full center-of-mass angular range of the K+. These new data extend the existing hyperon polarization data from CLAS in a similar kinematic range but from a significantly larger dataset. …

Collinear Factorization At Subasymptotic Kinematics And Validation In A Diquark Spectator Model, 2022 Old Dominion University

#### Collinear Factorization At Subasymptotic Kinematics And Validation In A Diquark Spectator Model, Juan V. Guerrero, Alberto Accardi

##### Physics Faculty Publications

We revisit the derivation of collinear factorization for Deep Inelastic Scattering at subasymptotic values of the four-momentum transfer squared, where the masses of the particles participating in the interaction cannot be neglected. By using an inclusive jet function to describe the scattered quark final state, we can restrict the needed parton kinematic approximations just to the four-momentum conservation of the hard scattering process, and explicitly expand the rest of the diagram in powers of the unobserved parton transverse momenta rather than neglecting those. This procedure provides one with more flexibility in fixing the virtuality of the scattered and recoiling partons …

2021 Southern Methodist University

#### Fast Statistical Methods For The Global Qcd Analysis Of The Proton Structure, Xiaoxian Jing

##### Physics Theses and Dissertations

Parton distribution functions (PDFs) quantify probabilities to find partons (quarks and gluons) in a hadron as a function of the fraction x of the hadron’s momentum carried by the parton at a given energy scale. PDFs play a critical role in precision tests of the Standard Model in Higgs boson production and other electroweak processes at the Large Hadron Collider (LHC), and in searches for physics beyond the Standard Model. PDFs are obtained by the global QCD analysis, which fits theoretical predictions to experimental measurements. PDF fitting and post-analysis are computationally intensive. This dissertation discusses fast statistical methods for the …

Study Of The Geometric Structure Of Low-Atomic Copper Clusters Using Computer Simulation, 2021 Ferghana Polytechnic Institute

#### Study Of The Geometric Structure Of Low-Atomic Copper Clusters Using Computer Simulation, Nodirbek Ikromjonovich Ibrokhimov

##### Scientific-technical journal

In this work, we investigated the geometric structure of small neutral copper clusters with low energy using the MD (Molecular Dynamics) method. When calculating the processes of interatomic interaction, we used a potential EAM (Embedded-atom method). A computer model of Cun (n = 2-13) clusters has been created. The geometric shapes of the Cu2, Cu3, Cu4, Cu5, Cu6, Cu7, Cu8, Cu9, Cu10, Cu11, Cu12, and Cu13 clusters have been studied and the structural parameters (Cu-Cu bond …

2021 University of Tennessee, Knoxville

#### Electroweak Interactions And Fundamental Symmetries In Light Nuclei With Short-Range Effective Field Theories, Zichao Yang

##### Doctoral Dissertations

Effective field theories(EFTs) are powerful tools to study nuclear systems that display separation of scales. In this dissertation, we present halo EFT results for the $\beta$-delayed proton emission from $^{11}$Be, and pionless EFT results for three-nucleon systems. Halo nuclei are simply described by a tightly bound core and loosely bound valence nucleons. Using the halo EFT, we calculate the rate of the rare decay $^{11}$Be, which is a well-known halo nucleus, into $^{10}\text{Be} + p +e^- + \bar{\nu}_e$. We assume a shallow $1/2 ^+$ resonance in the $^{10}$Be$-p$ system with an energy consistent with a recent experiment by Ayyad {\it …

2021 University of Tennessee, Knoxville

#### Search For New Physics In Rare Higgs Boson Decays With The Cms Detector At The Large Hadron Collider, Himal Acharya

##### Doctoral Dissertations

A new boson with a mass of 125 GeV was discovered at the large hadron collider (LHC) in July 2012. The properties of this particle are so far consistent with the standard model (SM) expectation. Differences in the Higgs boson decay rates and predicted by the SM might indicate the presence of new particles and forces between them. Particularly, rare exclusive decays of the Higgs boson are a promising laboratory to study physics beyond the standard model. Searches for decays of the Higgs boson into a Z boson and a J/ψ meson or into pairs of J/ψ or Υ mesons …

Lorentz Violations And The Casimir Effect, 2021 California Polytechnic State University, San Luis Obispo

#### 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 …

Space Charge Effects In Low Energy Magnetized Electron Beams, 2021 Old Dominion University

#### Space Charge Effects In Low Energy Magnetized Electron Beams, W. M. Sajini Anushika Kumari Wijethunga

##### Physics Theses & Dissertations

Magnetized electron cooling of the ion beam is one of the major approaches towards obtaining the required high luminosity in the proposed Electron-Ion Collider (EIC). To increase the cooling efficiency, a bunched electron beam with a high bunch charge and high repetition rate is required. However, these features can combine to enhance the collective interactions, such as the space charge effect. A magnetized electron beam was successfully generated at the Thomas Jefferson National Accelerator Facility (JLab) using a compact, 300 kV DC high voltage photo-gun with an inverted insulator geometry and bi-alkali antimonide photocathode. The beam magnetization was characterized using …

2021 William & Mary

#### Nonlocal Lorentz-Violating Modifications Of Qed, Qian Niu

We consider nonlocal Lorentz-violating theories, with infinite-derivative quadratic terms. The nonlocal modifications in the form of exponential damping in the propagator lead to a better convergence of amplitudes than in the local theories. Moreover, the nonlocal Lorentz-violating theories are ghost-free and unitary when formulated in Minkowski space. We compute the loop effects assuming one-parameter and two-parameter nonlocal functions. By comparing the lower bound of the nonlocality scale with the Planck scale, we rule out these theories. We then review a more general argument, developed by Collins et al. (2004), that a microscopic theory with Lorentz violation around the Planck scale …

2021 University of Massachusetts Amherst

#### A Search For Exotic Higgs Decays Or: How I Learned To Stop Worrying And Love Long-Lived Particles, Jackson Burzynski

##### Doctoral Dissertations

A novel search for exotic decays of the Higgs boson to pairs of long-lived neutral particles, each decaying to a bottom quark pair, is performed using 139 fb-1 of sqrt{s} = 13 TeV proton-proton collision data collected with the ATLAS detector at the LHC. Events consistent with the production of a Higgs boson in association with a leptonically-decaying Z boson are analyzed. Long-lived particle (LLP) decays are reconstructed from inner detector tracks as displaced vertices with high mass and track multiplicity relative to Standard Model processes. The analysis selection requires the presence of at least two displaced vertices, effectively …

2021 University of Massachusetts Amherst

#### Search For Resonant Pair Production Of Higgs Bosons In The Four B-Quark Final State With The Atlas Detector, Dale Abbott

##### Doctoral Dissertations

A search for heavy resonances decaying to Higgs boson pairs in the $b\overline{b}b\overline{b}$ final state with 139 $fb^{-1}$ of LHC proton-proton (pp) collision data collected at $\sqrt{s} = 13$ TeV obtained by the ATLAS detector during the 2015-2018 time period. Two benchmark signals are studied, both of which decay into a Higgs boson pair: a spin-2 Kaluza-Klein Graviton and a scalar resonance. This thesis studies high transverse momentum (boosted) resonances, which range from 900-5000 GeV. No statistically significant excesses are observed and the results are found to be compatible with the Standard Model. Upper limits are set on the production …

2021 Northeastern Illinois University

#### Acoustic Parameters As Discriminators Of Wall Events In Pico Dark Matter Search Data, Lucia Volkova

##### University Honors Program Senior Projects

Bubble chambers are one of several detector types that particle physicists use to search for the as-yet-undetected dark matter. The PICO collaboration – formed from the merger of the similar PICASSO and COUPP experiments – runs such a bubble detector using superheated fluorocarbons (with and without iodine). Bubbles that form along chamber walls exhibit different behavior than those which nucleate in the bulk of the target liquid due to shape distortions from the wall boundary; in previous analyses when searching for dark matter, these wall events have been cut from the data to control for the differing behavior using information …