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Heating and Thermalization of Minor Ions in the Solar Wind
Heating and Thermalization of Minor Ions in the Solar Wind
상세정보
- 자료유형
- 학위논문 서양
- 최종처리일시
- 20250211153015
- ISBN
- 9798384046202
- DDC
- 530
- 서명/저자
- Heating and Thermalization of Minor Ions in the Solar Wind
- 발행사항
- [Sl] : University of Michigan, 2024
- 발행사항
- Ann Arbor : ProQuest Dissertations & Theses, 2024
- 형태사항
- 171 p
- 주기사항
- Source: Dissertations Abstracts International, Volume: 86-04, Section: B.
- 주기사항
- Advisor: Lepri, Susan T.;Raines, Jim.
- 학위논문주기
- Thesis (Ph.D.)--University of Michigan, 2024.
- 초록/해제
- 요약In this thesis, the preferential heating of heavy ions in the solar wind has been explored in different solar wind types, throughout the solar cycle, and with radial distance from the Sun. The ambient solar wind is often observed to be out of local thermodynamic equilibrium. The mechanisms of thermalization, the time and spatial scales on which it occurs, and the extent of it in solar wind streams all provide insight into local energy transfer. Non-thermal features of the solar wind are well-ordered by collisional age and thus can be used to provide information about the origin of the nonthermal state. The varying charge states and masses of minor ions provide further information about the mechanisms driving the solar wind's state closer to the sun and its evolution toward thermodynamic equilibrium.In Chapter 2, which predicts the outer boundary of preferential heating for minor ions, collisional age is used to model the thermalization of minor ion species, predicting the radial distance at which preferential heating becomes less significant than thermalization due to Coulomb collisions. The results were compared to those found for alpha particles using WIND data, as well as a model of mass-dependent heating. Though the predictions of the preferential heating zone boundary were quite high, they did exhibit a clear mass and charge-to-mass dependence.In Chapter 3, which concerns the heating of minor ions in the slow Alfvenic wind, slow-Alfvenic (SA) intervals from SC 23 solar maximum were selected, as well as fast and non-Alfvenic intervals. SWICS 12-minute data was used to analyze the collisionality of these wind types, with the overall goal of determining whether or not the SA intervals were collisional enough to be used in the preferential heating zone boundary model. It was found that the distinct collisionality of the three wind types is not fully dependent on density and temperature, which are the driving factors of collisional frequency. The Preferential Heating Zone model was run on SA and slow non-Alfvenic (SNA) wind, finding that the model predicts a lower boundary for SA wind than for SNA. It was also found that the radial boundary height and normalized cross-helicity are anticorrelated, while excess temperature at the boundary, tended to be higher in the SNA wind. The variation in excess heating and boundary height with solar cycle is explored as a possible cause for the results, and other explanations, such as the variation of ion abundances in the different solar wind types are discussed as well. Overall, radial boundary, excess temperature, and their dependence on ion mass and charge-to mass in the slow wind with high Alfvenicity do not exhibit as much variability as the slow wind with low Alfvenicity.Chapter 4, which tracks heavy ion kinetics from the inner heliosphere to 1 AU, applies the preferential heating zone model to Heavy Ion Sensor (HIS) observations, allowing for the direct input of varying distances from the Sun. Direct observations of the relaxation of Tion/Tproton and ∆vip with radial distance and Ac are compared to each other, as well as modeled and observed trends in ion parameters. This is done for slow, fast, and combined wind. The transition from heating to thermalization is observed at low collisional ages. Preferential heating zone model predictions in varying ranges of radial distance are compared, finding that when including data beyond about 150 Rs, model predictions become well-ordered, providing a range of expected radial boundary predictions at varying spacecraft distances. The presence of mass and mass to charge dependent radial scaling in Chapters 2 and 4 and the absence of these dependencies in Chapter 3, which is limited to solar maximum and ascending maximum, indicate that the ordering of the boundary location is more strongly tied to the solar cycle than the extent of the heating.
- 일반주제명
- Physics
- 일반주제명
- Thermodynamics
- 일반주제명
- Energy
- 키워드
- Solar wind
- 키워드
- Heavy ions
- 키워드
- Solar cycle
- 키워드
- Thermalization
- 기타저자
- University of Michigan Applied Physics
- 기본자료저록
- Dissertations Abstracts International. 86-04B.
- 전자적 위치 및 접속
- 로그인 후 원문을 볼 수 있습니다.
MARC
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■00520250211153015
■006m o d
■007cr#unu||||||||
■020 ▼a9798384046202
■035 ▼a(MiAaPQ)AAI31631526
■035 ▼a(MiAaPQ)umichrackham005674
■040 ▼aMiAaPQ▼cMiAaPQ
■0820 ▼a530
■1001 ▼aHolmes, Janelle A.
■24510▼aHeating and Thermalization of Minor Ions in the Solar Wind
■260 ▼a[Sl]▼bUniversity of Michigan▼c2024
■260 1▼aAnn Arbor▼bProQuest Dissertations & Theses▼c2024
■300 ▼a171 p
■500 ▼aSource: Dissertations Abstracts International, Volume: 86-04, Section: B.
■500 ▼aAdvisor: Lepri, Susan T.;Raines, Jim.
■5021 ▼aThesis (Ph.D.)--University of Michigan, 2024.
■520 ▼aIn this thesis, the preferential heating of heavy ions in the solar wind has been explored in different solar wind types, throughout the solar cycle, and with radial distance from the Sun. The ambient solar wind is often observed to be out of local thermodynamic equilibrium. The mechanisms of thermalization, the time and spatial scales on which it occurs, and the extent of it in solar wind streams all provide insight into local energy transfer. Non-thermal features of the solar wind are well-ordered by collisional age and thus can be used to provide information about the origin of the nonthermal state. The varying charge states and masses of minor ions provide further information about the mechanisms driving the solar wind's state closer to the sun and its evolution toward thermodynamic equilibrium.In Chapter 2, which predicts the outer boundary of preferential heating for minor ions, collisional age is used to model the thermalization of minor ion species, predicting the radial distance at which preferential heating becomes less significant than thermalization due to Coulomb collisions. The results were compared to those found for alpha particles using WIND data, as well as a model of mass-dependent heating. Though the predictions of the preferential heating zone boundary were quite high, they did exhibit a clear mass and charge-to-mass dependence.In Chapter 3, which concerns the heating of minor ions in the slow Alfvenic wind, slow-Alfvenic (SA) intervals from SC 23 solar maximum were selected, as well as fast and non-Alfvenic intervals. SWICS 12-minute data was used to analyze the collisionality of these wind types, with the overall goal of determining whether or not the SA intervals were collisional enough to be used in the preferential heating zone boundary model. It was found that the distinct collisionality of the three wind types is not fully dependent on density and temperature, which are the driving factors of collisional frequency. The Preferential Heating Zone model was run on SA and slow non-Alfvenic (SNA) wind, finding that the model predicts a lower boundary for SA wind than for SNA. It was also found that the radial boundary height and normalized cross-helicity are anticorrelated, while excess temperature at the boundary, tended to be higher in the SNA wind. The variation in excess heating and boundary height with solar cycle is explored as a possible cause for the results, and other explanations, such as the variation of ion abundances in the different solar wind types are discussed as well. Overall, radial boundary, excess temperature, and their dependence on ion mass and charge-to mass in the slow wind with high Alfvenicity do not exhibit as much variability as the slow wind with low Alfvenicity.Chapter 4, which tracks heavy ion kinetics from the inner heliosphere to 1 AU, applies the preferential heating zone model to Heavy Ion Sensor (HIS) observations, allowing for the direct input of varying distances from the Sun. Direct observations of the relaxation of Tion/Tproton and ∆vip with radial distance and Ac are compared to each other, as well as modeled and observed trends in ion parameters. This is done for slow, fast, and combined wind. The transition from heating to thermalization is observed at low collisional ages. Preferential heating zone model predictions in varying ranges of radial distance are compared, finding that when including data beyond about 150 Rs, model predictions become well-ordered, providing a range of expected radial boundary predictions at varying spacecraft distances. The presence of mass and mass to charge dependent radial scaling in Chapters 2 and 4 and the absence of these dependencies in Chapter 3, which is limited to solar maximum and ascending maximum, indicate that the ordering of the boundary location is more strongly tied to the solar cycle than the extent of the heating.
■590 ▼aSchool code: 0127.
■650 4▼aPhysics
■650 4▼aThermodynamics
■650 4▼aEnergy
■653 ▼aSolar wind
■653 ▼aMinor ion heating
■653 ▼aHeavy ions
■653 ▼aSolar cycle
■653 ▼aThermalization
■690 ▼a0605
■690 ▼a0348
■690 ▼a0791
■71020▼aUniversity of Michigan▼bApplied Physics.
■7730 ▼tDissertations Abstracts International▼g86-04B.
■790 ▼a0127
■791 ▼aPh.D.
■792 ▼a2024
■793 ▼aEnglish
■85640▼uhttp://www.riss.kr/pdu/ddodLink.do?id=T17164551▼nKERIS▼z이 자료의 원문은 한국교육학술정보원에서 제공합니다.
