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Dissertations / Theses on the topic 'Solar energetic particles'

Author: Grafiati

Published: 4 June 2021

Last updated: 1 August 2024

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1

Sollitt, Luke Stone Edward. "Ionic charge states of solar energetic particles /." Diss., Pasadena, Calif. : California Institute of Technology, 2004. http://resolver.caltech.edu/CaltechETD:etd-09122003-110331.

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2

Pei, Chunsheng. "Solar Energetic Particle Transport in the Heliosphere." Diss., The University of Arizona, 2007. http://hdl.handle.net/10150/194303.

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The transport of solar energetic particles (SEPs) in the inner heliosphere is a very important issue which can affect our daily life. For example, large SEP events can lead to the failure of power grids, interrupt communications, and may participate in global climate change. The SEPS also can harm humans in space and destroy the instruments on board spacecraft. Studying the transport of SEPs also helps us understand remote regions of space which are not visible to us because there are not enough photons in those places.The interplanetary magnetic field is the medium in which solar energetic pa

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3

Chollet, Eileen Emily. "Solar-Energetic Particles as a Probe of the Inner Heliosphere." Diss., The University of Arizona, 2008. http://hdl.handle.net/10150/195499.

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In this dissertation, I explore the relationship between solar energetic particles (SEPs) and the interplanetary magnetic field, and I use observations of SEPs to probe the region of space between the Sun and the Earth. After an introduction of major concepts in heliospheric physics, describing some of the history of energetic particles and defining the data sets used in the work, the rest of this dissertation is organized around three major concepts related to energetic particle transport: magnetic field-line length, interplanetary turbulence, and particle scattering and diffusion. In Chapt

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4

Sun, P., J. R. Jokipii, and J. Giacalone. "PITCH-ANGLE SCATTERING OF ENERGETIC CHARGED PARTICLES IN NEARLY CONSTANT MAGNITUDE MAGNETIC TURBULENCE." IOP PUBLISHING LTD, 2016. http://hdl.handle.net/10150/621389.

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We use a method developed by Roberts. that optimizes the phase angles of an ensemble of plane waves with amplitudes determined from a Kolmogorov-like power spectrum, to construct magnetic field vector fluctuations having nearly constant magnitude and large variances in its components. This is a representation of the turbulent magnetic field consistent with that observed in the solar wind. Charged-particle pitch-angle diffusion coefficients are determined by integrating the equations of motion for a large number of charged particles moving under the influence of forces from our predefined magne

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5

Sreeraj, T. "Generation of low frequency waves by energetic particles in space plasmas." Thesis, IIG, 2010. http://localhost:8080/xmlui/handle/123456789/1595.

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6

Druett, Malcolm. "The effects of energetic particles on radiative transfer and emission from hydrogen in solar flares." Thesis, Northumbria University, 2017. http://nrl.northumbria.ac.uk/36222/.

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There are rapid increases of hard and soft X-rays (HXR, SXR) and ultraviolet (UV) emission with large Doppler blue-shifts associated with plasma up-flows observed at flare onsets accompanied by broadened chromospheric emission with large redshifts. Hα shows red-shifts of 1–4 Å in the impulsive phase of solar flares observed with various past (Ichimoto and Kurokawa, 1984;Wuelser and Marti, 1989) and current (the Swedish Solar Telescope, SST) instruments (Druett et al., 2017). HXR footpoints are observed to be co-temporal and co-spatial with increases in white light (WL) and continuous emission

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7

Pacheco, Mateo Daniel. "Analysis and modelling of the solar energetic particle radiation environment in the inner heliosphere in preparation for Solar Orbiter." Doctoral thesis, Universitat de Barcelona, 2019. http://hdl.handle.net/10803/667033.

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The Sun is the main source of all kind of solar energetic particles in the Solar System, electrons, protons and ions with energies from few keV to several GeV. These particles are released from the solar corona and spread through the interplanetary space, the heliosphere, influenced by the interplanetary magnetic field and arriving to the Earth and interacting with the terrestrial magnetosphere. The effects of SEP interactions with space-based devices, manned missions and the Earth atmosphere are encompassed by what is known as space weather. This thesis describes the work we performed on thi

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8

Mallik, Procheta Chandra Vasu. "Diagnostics of solar flare energetic particles : neglected hard X-ray processes and neutron astronomy in the inner heliosphere." Thesis, University of Glasgow, 2010. http://theses.gla.ac.uk/1510/.

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For work on my thesis dissertation, we have been studying some energetic processes in solar flares. On our work on hard X-ray (HXR) emission from flares, we have shown that non-thermal recombination emission can compare with the bremsstrahlung HXR flux for certain flare conditions. In this thesis, we show spectral features characteristic of non-thermal recombination HXR emission and suggest how it plays a signicant role in the flare HXR continuum, something that has been ignored in the past. It is important to note that these results could demand a reconsideration of the numbers of accelerated

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9

Kühl, Patrick [Verfasser]. "Energy Spectra of near relativistic Galactic Cosmic Rays and Solar Energetic Particles - Extending the Measurement Capabilities of EPHIN / Patrick Kühl." Kiel : Universitätsbibliothek Kiel, 2017. http://d-nb.info/1141176114/34.

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10

Musset, Sophie. "Accélération et propagation des particules énergétiques dans la couronne solaire : de l'analyse des données de l'instrument RHESSI à la préparation de l'exploitation de l'instrument STIX sur Solar Orbiter." Thesis, Paris Sciences et Lettres (ComUE), 2016. http://www.theses.fr/2016PSLEO011/document.

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Le soleil est une étoile active, et les éruptions solaires sont une des manifestations de cette activité. Il est admis que l'énergie disponible pour les éruptions solaires a une origine magnétique, et est transmise au milieu lors de phénomènes de reconnexion magnétique dans la couronne. Une partie de cette énergie permet d'accélérer les particules du milieu (électrons et ions). Cependant, les détails concernant les conditions dans lesquelles les particules sont accélérées et se propagent des régions d'accélération aux sites d'interaction lors des éruptions solaires ne sont pas encore tous comp

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11

Swalwell, Bill. "False alarms in the forecasting of Solar Energetic Particle events." Thesis, University of Central Lancashire, 2018. http://clok.uclan.ac.uk/23607/.

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Solar Energetic Particles (SEPs) are known to be accelerated by high-energy events in the Sun's corona: coronal mass ejections (CMEs) with high speed, solar flares with high peak emission in soft X-rays, or a combination of the two. SEPs, however, are not detected following all fast CMEs or intense flares. Those large solar events, which might reasonably have been expected to produce SEPs at Earth but which failed to do so, may be termed “false alarms”. In this work, two simple SEP forecasting algorithms are defined: one (algorithm A.1) is based upon the observation of a magnetically well-conn

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12

Zelina, Peter. "Multi-instrument studies of heavy ion solar energetic particle transport." Thesis, University of Central Lancashire, 2017. http://clok.uclan.ac.uk/20923/.

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In this thesis, an analysis of solar energetic particle (SEP) data from multiple instruments onboard the ACE, SOHO and STEREO spacecraft is presented. The temporal variation and the dependence of heavy ion abundances on solar longitude were studied and quantitatively characterised during SEP events between 2006 and 2016. Ionic abundances vary over the duration of SEP events, e.g. Fe/O often shows a decrease over time. This behaviour was identified as a common characteristic within the data. The time variation of 36 different ionic pairs was studied for a number of SEP events. The fit constant

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13

Laitinen, Timo. "Energetic particle acceleration and transport in wave-heated solar wind /." Turku : Turun Yliopisto, 2003. http://www.gbv.de/dms/goettingen/37199182X.pdf.

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14

Wijsen, Nicolas. "PARADISE: a model for energetic particle transport in the solar wind." Doctoral thesis, Universitat de Barcelona, 2020. http://hdl.handle.net/10803/671827.

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Our modern society is becoming increasingly dependent on the constant stream of information sent out by satellites orbiting Earth. However, highly energetic rays traversing the near-Earth space environment pose a constant threat to the electronics on board these satellites. In addition, humankind renewed interest in manned missions to the Moon and Mars requires the protection of the spacecraft crew members against the high radiation doses that they will encounter during their interplanetary voyage. A profound understanding of the ever changing radiation conditions in our solar system is thus

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15

Jiggens, Piers T. A. "A new solar energetic particle event modelling methodology incorporating system memory." Thesis, University of Southampton, 2011. https://eprints.soton.ac.uk/181507/.

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16

Takasaki, Hiroyuki. "Energetic phenomena of the solar flares : plasmoid ejections and particle transport and acceleration." 京都大学 (Kyoto University), 2006. http://hdl.handle.net/2433/144187.

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Kyoto University (京都大学)<br>0048<br>新制・課程博士<br>博士(理学)<br>甲第12104号<br>理博第2998号<br>新制||理||1447(附属図書館)<br>23940<br>UT51-2006-J99<br>京都大学大学院理学研究科物理学・宇宙物理学専攻<br>(主査)教授柴田一成, 助教授岩室史英, 教授長田哲也<br>学位規則第4条第1項該当

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17

Lu, Hua, Mark A. Clilverd, Annika Seppälä, and Lon L. Hood. "Geomagnetic perturbations on stratospheric circulation in late winter and spring." AMER GEOPHYSICAL UNION, 2008. http://hdl.handle.net/10150/623326.

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This study investigates if the descent of odd nitrogen, generated in the thermosphere and the upper mesosphere by energetic particle precipitation (EPP-NOx), has a detectable impact on stratospheric wind and temperature in late winter and spring presumably through the loss of ozone and reduction of absorption of solar UV. In both hemispheres, similar downward propagating geomagnetic signals in the extratropical stratosphere are found in spring for those years when no stratospheric sudden warming occurred in mid-winter. Anomalous easterly winds and warmer polar regions are found when the 4-mont

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18

Johnson, Victoria Charlotte Anna. "The spatial and temporal response of geopotential height and temperature to energetic solar particle events (1976-2004)." Thesis, Imperial College London, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.497896.

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19

Maliniemi, V. (Ville). "Observations of solar wind related climate effects in the Northern Hemisphere winter." Doctoral thesis, University of Oulu, 2016. http://urn.fi/urn:isbn:9789526213545.

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Abstract This thesis studies the long-term relation between the solar wind driven energetic particle forcing into the atmosphere and the tropospheric circulation in the Northern Hemisphere winter. The work covers the period of more than one hundred years since the turn of the 20th century to present. The thesis makes a statistical analysis of satellite measurements of precipitating energetic electrons, sunspot number data and geomagnetic activity, and compares them with temperature and pressure measurements made at the Earth's surface. Recent results, both observational and from chemistry clim

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20

Sollitt, Luke. "Ionic Charge States of Solar Energetic Particles." Thesis, 2004. https://thesis.library.caltech.edu/3493/1/thesis.pdf.

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<p>A novel technique to infer average ionic charge states of high energy (≥ 10 MeV/nuc) solar energetic particles (SEPs) in large solar events is presented. In some large SEP events, it is observed that higher energy SEPs decay in intensity more rapidly than at lower energies. Furthermore, this energy dependence varies with particle species, as would be expected if the decay timescale depended on a rigidity-dependent diffusive mean free path. Observations are done with the Solar Isotope Spectrometer (SIS) on board the Advanced Composition Explorer spacecraft. By comparing the decay timescales

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21

Trotta, Enrico Maria, Roberto Bertolini, and Gaetano Zimbardo. "A Lévy Walk approach to the propagation of solar energetic particles." Thesis, 2013. http://hdl.handle.net/10955/1015.

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Scuola di Dottorato Scienza e Tecnica "Bernardino Telesio", Fisica dei Sistemi Complessi, XXV Ciclo, a.a. 2013<br>This thesis is dedicated to the problem of energetic particle propagation in the solar wind, with special emphasis on the propagation of solar energetic particles (SEPs). Those particles are accelerated either in the low corona by flares, usually giving rise to so-called impulsive SEP events, or in the higher corona by the shock driven by coronal mass ejections, giving rise to the so-called gradual SEP events. In either case, energetic particles propagate in the solar wind alon

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22

Kornbleuth, Marc Zachary. "Using hydrogen energetic neutral atoms to study the heliosphere." Thesis, 2020. https://hdl.handle.net/2144/42001.

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The interaction between the solar wind and the partially ionized gas of the local interstellar medium (ISM) creates a bubble known as the heliosphere. Classically, the shape of the heliosphere has been regarded as comet-like, with a long tail pointed in the direction opposite the Sun’s motion through the ISM. In this view, the solar magnetic field was assumed to have a negligible effect on the global structure of the heliosphere. Recent advances in numerical modeling have revealed the importance of the solar magnetic field in its ability to confine and collimate the solar wind plasma, and the

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23

Garcia-Rigo, A., M. Nunez, Rami S. R. Qahwaji, et al. "Prediction and warning system of SEP events and solar flares 4 for risk estimation in space launch operations." 2016. http://hdl.handle.net/10454/8607.

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Yes<br>A web-based prototype system for predicting solar energetic particle (SEP) events and solar flares for use by space launch operators is presented. The system has been developed as a result of the European Space Agency (ESA) project SEPsFLAREs (Solar Events Prediction system For space LAunch Risk Estimation). The system consists of several modules covering the prediction of solar flares and early SEP Warnings (labeled Warning tool), the prediction of SEP event occurrence and onset, and the prediction of SEP event peak and duration. In addition, the system acquires data for solar flare no

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24

Damiani, A. "EFFECTS OF ENERGETIC SOLAR PARTICLES ON OZONE AND MINOR ATMOSPHERIC COMPONENTS INSIDE THE POLAR REGIONS." Thesis, 2007. http://hdl.handle.net/2122/4165.

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Solar activity influences the Earth’s environment, in particular the atmospheric ozone, by the direct output of the e.m. radiation or through the variability of the incoming cosmic ray flux (solar and galactic particles). Especially energetic particles, arising from huge explosions on the Sun’s surface, travel in the interplanetary medium and, if the circumstances were favorable, they could enter the terrestrial atmosphere (driven by the geomagnetic field lines of our planet) and reach the polar cap regions (geomagnetic latitude > 60°). There, they provide additional external energy and

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25

JordanVannitsen and 方喬丹. "Propagation of Solar Energetic Particles in inter-planetary space by study of the particles spreading across the Interplanetary Magnetic Field." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/27x95z.

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博士<br>國立成功大學<br>航空太空工程學系<br>107<br>This thesis presents a Multi-satellite Data Analysis and Simulator Tool (MDAST), developed with the original goal to support the science requirements of a Martian 3-Unit CubeSat mission profile named Bleeping Interplanetary Radiation Determination Yo-yo (BIRDY). MDAST was firstly designed and tested by taking into account the positions, attitudes, instruments field of view and energetic particles flux measurements from four spacecraft (ACE, MSL, STEREO A, and STEREO B). The focus of this thesis will be in the period 6 December 2011 - 14 July 2012, period duri

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26

Williams, Daniel LeRoy. "Measurements of the isotopic composition of solar energetic particles with the MAST instrument aboard the SAMPEX spacecraft." Thesis, 1998. https://thesis.library.caltech.edu/4192/1/Williams_dl_1998.pdf.

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NOTE: Text or symbols not renderable in plain ASCII are indicated by [...]. Abstract is included in .pdf document. We report measurements of the isotopic composition of solar energetic particles (SEP) as observed in two gradual solar energetic particle events which began on 30 October and 2 November of 1992. These measurements were taken by the Mass Spectrometer Telescope (MAST), a charged-particle telescope on board the SAMPEX satellite in a polar, low-Earth orbit. The elements measured are carbon, nitrogen, oxygen, neon, magnesium and silicon, which are observed over an energy interval of

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27

Hall, Michael Ian. "Estimates of Linear Energy Transfer from Solar Energetic Particles in Earth's Upper Atmosphere to Human Tissue in Aluminium Aircraft." 2011. http://trace.tennessee.edu/utk_gradthes/876.

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Radiation from extraterrestrial sources is a concern for the safety of passengers and crew in high altitude aircraft. Cosmic radiation and solar particles constantly bombard the atmosphere with energy. Radiation levels from these sources can vary considerably depending on solar activity cycles and energetic particle events such as solar flares. In order to predict the effects of such events the nature of the radiation spectrum must be characterized, and the individual effects of each radiation type understood. The background radiation spectrum is known to good accuracy and prediction of radiat

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28

Lampa, Florian. "Modeling Solar Cosmic Ray Transport within the Ecliptic Plane." Doctoral thesis, 2012. https://repositorium.ub.uni-osnabrueck.de/handle/urn:nbn:de:gbv:700-2012040410112.

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Since six decades the understanding of interplanetary propagation of solar flare accelerated, energetic charged particles in the inner heliosphere has not yet achieved sufficient closure. The essential mechanisms acting on these charged particles, which perform helical orbits along the large-scale magnetic field lines as probes, have already been identified. However, in particular the impact of the three-dimensional, small-scale magnetic fluctuations on the particles' trajectories has not yet been fully understood. These superimposed disturbances are expected to interact with the charges via r

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29

Ravishankar, Anitha. "Study of coronal mass ejectionss (CMEs) using stereo and SOHO observations." Praca doktorska, 2021. https://ruj.uj.edu.pl/xmlui/handle/item/266807.

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30

Breneman, Hugh Herbert III. "Solar Photospheric and Coronal Abundances from Solar Energetic Particle Measurements." Thesis, 1985. https://thesis.library.caltech.edu/8686/2/Berneman%201985.pdf.

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<p>Observations of solar energetic particles (SEPs) from 22 solar flares in the 1977-1982 time period are reported. The observations were made by the Cosmic Ray Subsystem on board the Voyager 1 and 2 spacecraft. SEP abundances have been obtained for all elements with 3 ≤ Z ≤ 30 except Li, Be, B, F, Sc, V, Co and Cu, for which upper limits have been obtained. Statistically meaningful abundances of several rare elements (e.g., P, Cl, K, Ti, Mn) have been determined for the first time, and the average abundances of the more abundant elements have been determined with improved precision, typically

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31

Daou, Antoun Georges. "Observational and theoretical interpretation of energetic particle transport in solar flares." Thesis, 2008. http://hdl.handle.net/1911/22162.

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The combination of excellent space-based remote sensing, and image reconstruction techniques, as well as improvements in numerical modeling, help enhance our understanding of particle transport in solar flares. We conduct a rigorous analysis of flare hard X-ray emission using the unprecedented spectral and spatial resolution of the RHESSI telescope data in order to better understand the spectral properties of the emitting electron population in solar flares. We complete our study with a forward-fit to the data using a Fokker-Planck kinetic code, to numerically model the particle transport in p

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32

Orloff, Seth Michael. "A computational investigation of solar energetic particle trajectories in model magnetospheres." Thesis, 1999. http://hdl.handle.net/1911/19414.

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This work studies the dynamic behavior of solar energetic particles (SEPs, defined as protons and electrons with energies of 1 MeV to 1 GeV) by simulating their motion in model electromagnetic fields. Because of the hazards they pose to orbiting spacecraft and manned spaceflight operations, these species must be included in modern modeling efforts, including forthcoming space weather models. In this thesis, we describe an original computer program called the Solar Energetic Particle Tracer (SEPTR). As part of an operational computer model, SEPTR calculates the upper rigidity cutoffs for partic

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33

Chiang, Min Fan, and 范姜敏. "Effect of solar proton events on earth''s radiation belt : observations of energetic particle from Van Allen Probe." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/pb8mc4.

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碩士<br>淡江大學<br>航空太空工程學系碩士班<br>106<br>In this study, the environmental impact from the solar proton events, specifically on the inner radiation belt, are analyzed based on observations by the Van Allen Probe. The solar proton events occurred from 2013 to 2015 are selected and data of proton recorded by Relativistic Proton Spectrometer at these event times are analyzed. The analyzed results show that the proton differential fluxes increases when solar proton events occurred, and the onset time of these increases are earlier than the onset time of solar proton events defined by observations from G

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34

Wissing, Jan Maik. "Analysis of Particle Precipitation and Development of the Atmospheric Ionization Module OSnabrück - AIMOS." Doctoral thesis, 2011. https://repositorium.ub.uni-osnabrueck.de/handle/urn:nbn:de:gbv:700-201108318300.

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The goal of this thesis is to improve our knowledge on energetic particle precipitation into the Earth’s atmosphere from the thermosphere to the surface. The particles origin from the Sun or from temporarily trapped populations inside the magnetosphere. The best documented influence of solar (high-) energetic particles on the atmosphere is the Ozone depletion in high latitudes, attributed to the generation of HOx and NOx by precipitating particles (Crutzen et al., 1975; Solomon et al., 1981; Reid et al., 1991). In addition Callis et al. (1996b, 2001) and Randall et al. (2005, 2006) point out

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35

Lue, Charles. "Solar Wind Proton Interactions with Lunar Magnetic Anomalies and Regolith." Doctoral thesis, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-111254.

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The lunar space environment is shaped by the interaction between the Moon and the solar wind. In the present thesis, we investigate two aspects of this interaction, namely the interaction between solar wind protons and lunar crustal magnetic anomalies, and the interaction between solar wind protons and lunar regolith. We use particle sensors that were carried onboard the Chandrayaan-1 lunar orbiter to analyze solar wind protons that reflect from the Moon, including protons that capture an electron from the lunar regolith and reflect as energetic neutral atoms of hydrogen. We also employ comput

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