Author:

Abstract:

Solar energetic particles (SEPs), are primarily protons, electrons, and heavy ions accelerated to high energies from solar eruptive phenomena such as solar flares and coronal mass ejections (CMEs). Additionally, the inner heliosphere is a stage for energetic storm particle (ESP) events in the vicinity of CME-driven shocks and energetic particles in corotating interaction regions (CIRs), each contributing unique characteristics to the heliospheric energetic particle population. Understanding energetic particle events in the inner heliosphere is crucial for space weather. Motivated by the necessity to advance our predictive capabilities of energetic particle events, this dissertation focuses on developing a data-driven three-dimensional particle acceleration and transport model called Heliospheric Energetic Particle Acceleration and Transport (HEPAT), which is coupled with a data-driven magnetohydrodynamic (MHD) model of the inner heliosphere known as EUropean Heliospheric FORecasting Asset (EUHFORIA). The combined HEPAT and EUHFORIA models are then applied to simulate various energetic particle events in the inner heliosphere, including widespread SEP events, ESP events, and CIR ion events. From the crucial effects of IP shocks on SEP events to the dynamics of particle injection and escape in ESP events, and the mass-to-charge ratio dependence of ion spectra in CIRs, this thesis not only deepens our understanding of energetic particle events but also provides an important tool for the future space weather research.