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Tracing Alfven Waves, Turbulence, and Gaussian Structures in the Upper Corona and Inner Heliosphere With In-Situ Measurements, Statistical Analyses, and Modeling
Tracing Alfven Waves, Turbulence, and Gaussian Structures in the Upper Corona and Inner Heliosphere With In-Situ Measurements, Statistical Analyses, and Modeling
상세정보
- 자료유형
- 학위논문 서양
- 최종처리일시
- 20250211152004
- ISBN
- 9798382820606
- DDC
- 523
- 저자명
- Huang, Zesen.
- 서명/저자
- Tracing Alfven Waves, Turbulence, and Gaussian Structures in the Upper Corona and Inner Heliosphere With In-Situ Measurements, Statistical Analyses, and Modeling
- 발행사항
- [Sl] : University of California, Los Angeles, 2024
- 발행사항
- Ann Arbor : ProQuest Dissertations & Theses, 2024
- 형태사항
- 194 p
- 주기사항
- Source: Dissertations Abstracts International, Volume: 85-12, Section: B.
- 주기사항
- Advisor: Velli, Marco C. M.
- 학위논문주기
- Thesis (Ph.D.)--University of California, Los Angeles, 2024.
- 초록/해제
- 요약Parker Solar Probe (PSP) was launched in late 2018, and since then it has been providing in situ measurements of the inner heliosphere and upper solar corona. The journey of PSP to the Sun is continuously pushing the frontiers of heliophysics. In this dissertation, by combining in situ observations and computer simulations, we aimed to bring new insights from PSP to our current understanding of Alfven waves, turbulence, and solar wind structures. The primary results of this dissertation are the following: (1) Through 1D MHD simulation, we show that the total wave action is conserved in the linear mode conversion of magnetosonic waves at the equipartition layer (where the sound speed equals the Alfven speed); (2) Close to the Sun, contrary to standard solar wind turbulence models, the energy-containing 1/f range disappears in solar wind turbulence. Instead, the low-frequency turbulence spectrum is characterized by a shallow-inertial double power law, where the low-frequency part scales like f −0.5 ; (3) The in situ observed magnetic field magnitude B shows a surprisingly sensitive response to Gaussianity tests, which leads to a scale- and location-dependent Gaussianity scalogram, unveiling coherent structures spanning seven orders of magnitude in time. Notably, combined with Potential Field Source Surface (PFSS) modeling, we confirmed that the radially normalized B follows a near-perfect Gaussian distribution when PSP is immersed in magnetic field lines that are connected back to coronal holes. Additionally, computer simulations show that Gaussian distribution is the natural relaxation state for Alfvenic turbulence. (4) The shallow-inertial double power law indicates a concentration of fluctuation energy around the 'bend' in spectral slopes. Based on statistics from the first 17 PSP encounters, we found a systematic trend that the primary fluctuation frequency decreases with solar wind advection time and eventually saturates at around 3 minutes for the most pristine solar wind. This is consistent with remote sensing observations of the chromosphere, and indicates that the Alfven waves in the solar wind could ultimately be driven by p-mode oscillations in the photosphere. Our results have two primary implications: (1) Gaussianity of B serves as a good parameter for identifying structures in the solar wind, especially the time intervals that are magnetically connected to coronal holes; (2) Alfven waves in the solar wind are likely originating from the solar convection zone resonance chamber. Therefore, this dissertation can serve as a preliminary study to provide constraints on the formation of 1/f energy containing range and coronal heating mechanisms.
- 일반주제명
- Astrophysics
- 일반주제명
- Geophysics
- 일반주제명
- Plasma physics
- 일반주제명
- Statistical physics
- 키워드
- Alfven waves
- 키워드
- Helioseismology
- 키워드
- Solar physics
- 키워드
- Solar wind
- 키워드
- Turbulence
- 기타저자
- University of California, Los Angeles Geophysics & Space Physics 0406
- 기본자료저록
- Dissertations Abstracts International. 85-12B.
- 전자적 위치 및 접속
- 로그인 후 원문을 볼 수 있습니다.
MARC
008250123s2024 us c eng d■001000017162369
■00520250211152004
■006m o d
■007cr#unu||||||||
■020 ▼a9798382820606
■035 ▼a(MiAaPQ)AAI31330273
■040 ▼aMiAaPQ▼cMiAaPQ
■0820 ▼a523
■1001 ▼aHuang, Zesen.
■24510▼aTracing Alfven Waves, Turbulence, and Gaussian Structures in the Upper Corona and Inner Heliosphere With In-Situ Measurements, Statistical Analyses, and Modeling
■260 ▼a[Sl]▼bUniversity of California, Los Angeles▼c2024
■260 1▼aAnn Arbor▼bProQuest Dissertations & Theses▼c2024
■300 ▼a194 p
■500 ▼aSource: Dissertations Abstracts International, Volume: 85-12, Section: B.
■500 ▼aAdvisor: Velli, Marco C. M.
■5021 ▼aThesis (Ph.D.)--University of California, Los Angeles, 2024.
■520 ▼aParker Solar Probe (PSP) was launched in late 2018, and since then it has been providing in situ measurements of the inner heliosphere and upper solar corona. The journey of PSP to the Sun is continuously pushing the frontiers of heliophysics. In this dissertation, by combining in situ observations and computer simulations, we aimed to bring new insights from PSP to our current understanding of Alfven waves, turbulence, and solar wind structures. The primary results of this dissertation are the following: (1) Through 1D MHD simulation, we show that the total wave action is conserved in the linear mode conversion of magnetosonic waves at the equipartition layer (where the sound speed equals the Alfven speed); (2) Close to the Sun, contrary to standard solar wind turbulence models, the energy-containing 1/f range disappears in solar wind turbulence. Instead, the low-frequency turbulence spectrum is characterized by a shallow-inertial double power law, where the low-frequency part scales like f −0.5 ; (3) The in situ observed magnetic field magnitude B shows a surprisingly sensitive response to Gaussianity tests, which leads to a scale- and location-dependent Gaussianity scalogram, unveiling coherent structures spanning seven orders of magnitude in time. Notably, combined with Potential Field Source Surface (PFSS) modeling, we confirmed that the radially normalized B follows a near-perfect Gaussian distribution when PSP is immersed in magnetic field lines that are connected back to coronal holes. Additionally, computer simulations show that Gaussian distribution is the natural relaxation state for Alfvenic turbulence. (4) The shallow-inertial double power law indicates a concentration of fluctuation energy around the 'bend' in spectral slopes. Based on statistics from the first 17 PSP encounters, we found a systematic trend that the primary fluctuation frequency decreases with solar wind advection time and eventually saturates at around 3 minutes for the most pristine solar wind. This is consistent with remote sensing observations of the chromosphere, and indicates that the Alfven waves in the solar wind could ultimately be driven by p-mode oscillations in the photosphere. Our results have two primary implications: (1) Gaussianity of B serves as a good parameter for identifying structures in the solar wind, especially the time intervals that are magnetically connected to coronal holes; (2) Alfven waves in the solar wind are likely originating from the solar convection zone resonance chamber. Therefore, this dissertation can serve as a preliminary study to provide constraints on the formation of 1/f energy containing range and coronal heating mechanisms.
■590 ▼aSchool code: 0031.
■650 4▼aAstrophysics
■650 4▼aGeophysics
■650 4▼aPlasma physics
■650 4▼aStatistical physics
■653 ▼aAlfven waves
■653 ▼aHelioseismology
■653 ▼aMagnetohydrodynamics
■653 ▼aSolar physics
■653 ▼aSolar wind
■653 ▼aTurbulence
■690 ▼a0596
■690 ▼a0373
■690 ▼a0759
■690 ▼a0467
■690 ▼a0217
■71020▼aUniversity of California, Los Angeles▼bGeophysics & Space Physics 0406.
■7730 ▼tDissertations Abstracts International▼g85-12B.
■790 ▼a0031
■791 ▼aPh.D.
■792 ▼a2024
■793 ▼aEnglish
■85640▼uhttp://www.riss.kr/pdu/ddodLink.do?id=T17162369▼nKERIS▼z이 자료의 원문은 한국교육학술정보원에서 제공합니다.
