자료유형  

 학위논문

Control Number  

0017162273

International Standard Book Number  

9798384092971

Dewey Decimal Classification Number  

530

Main Entry-Personal Name  

Lin, Xincheng.

Publication, Distribution, etc. (Imprint  

[S.l.] : Duke University., 2024

Publication, Distribution, etc. (Imprint  

Ann Arbor : ProQuest Dissertations & Theses, 2024

Physical Description  

199 p.

General Note  

Source: Dissertations Abstracts International, Volume: 86-03, Section: B.

General Note  

Advisor: Springer, Roxanne.

Dissertation Note  

Thesis (Ph.D.)--Duke University, 2024.

Summary, Etc.  

요약Effective field theory (EFT) is a powerful tool for studying physical systems characterized by separated length scales. An EFT captures essential features of a physical system at a certain scale by including interactions informed by symmetries and expanded in ratios between length scales. In this way, an EFT provides a relatively simple way to obtain systematically improvable predictions of observables at a certain scale.Pionless EFT (EFT(π)), one of the low-energy EFTs of quantum chromodynamics (QCD), has proven its success in describing few-nucleon systems. As a member of a broader class of short-range EFTs consisting of contact interactions, EFT(π) has a well-understood renormalization, displays a high degree of universality, and can be used to study few-nucleon systems semi-analytically. In this thesis, we present our EFT(π) studies of cold neutron-deuteron capture into the triton and a photon (nd → 3Hγ) and dark matter (DM) scattering off light nuclei; we also present a short-range EFT study of the four-boson system. We incorporate approximate symmetries in our studies to help understand these processes.For cold nd capture, we calculate the cold nd capture cross section (σnd) up to and including next-to-next-to-leading order (NNLO) in EFT(π) and use the Wigner-SU(4) symmetry to understand the suppression on the contribution from the single-nucleon magnetic currents, as observed in previous calculations using potential models or other EFTs. We also identify a three-nucleon magnetic moment counterterm needed to renormalize both σnd and the triton magnetic moment at NNLO. For DM-light-nuclei scattering, we compute the DM-nuclei cross section for A ≤ 3 up to and including next-to-leading order in EFT(π) and use the large-Nc (number of QCD colors) expansion to constrain the contribution from different one- and two-nucleon-DM interactions; this study helps understand how DM may interaction with nucleons with future experiments using light nuclei as targets. For the four-boson system where discrete scaling symmetry plays a crucial role, we investigate the renormalization of four-body binding energies for cold 4He atoms and their behavior near the unitary limit; this calculation is also a precursor to four-nucleon calculations.

Subject Added Entry-Topical Term  

Physics.

Subject Added Entry-Topical Term  

Nuclear physics.

Subject Added Entry-Topical Term  

Quantum physics.

Index Term-Uncontrolled  

Effective field theory

Index Term-Uncontrolled  

Few-body systems

Index Term-Uncontrolled  

Quantum chromodynamics

Index Term-Uncontrolled  

Magnetic moment

Index Term-Uncontrolled  

Dark matter

Added Entry-Corporate Name  

Duke University Physics

Host Item Entry  

Dissertations Abstracts International. 86-03B.

Electronic Location and Access  

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Control Number  

joongbu:657905