EAGER: Novel Approach to Acceleration and Escape of Charged Particles at Interplanetary and Astrophysical Shock Waves

GSTDTAP

项目编号	1850774
	EAGER: Novel Approach to Acceleration and Escape of Charged Particles at Interplanetary and Astrophysical Shock Waves
	Federico Fraschetti (Principal Investigator)
主持机构	University of Arizona
项目开始年	2018
	2018-11-01
项目结束日期	2019-10-31
资助机构	US-NSF
项目类别	Standard Grant
项目经费	99411(USD)
国家	美国
语种	英语
英文摘要	The modelling of particle acceleration at shocks is expected to pave the path to improved understanding of the origin of cosmic-rays, which were discovered more than 100 years ago. The current standard model of Diffusive Shock Acceleration (DSA) applies to the case of ideal, infinitely planar shock front; the process of acceleration is self-sustained if particles can contrast the flow advection and return to the shock to undergo further acceleration. If particles cannot be confined in proximity of the shocks, then the DSA approach is not feasible. The main focus of this one-year EAGER project is to explore a novel approach to explain the observations of energetic particles that do not fit in the DSA paradigm. This approach will comprise both analytic and numerical analyses, which support the interpretation of spacecraft data. The research project will produce an advanced theoretical model that may explain the measurements of shocks near the Earth, as well as observations of a variety of astrophysical sources, including pulsar wind nebulae, blazars, supernova remnants, etc. This one-year EAGER project is aimed at transforming our present understanding of the acceleration of charged particles at interplanetary and astrophysical shock waves. Several interplanetary shock events exhibit broken power-law spectra of the energetic particles. Such spectra fall outside the regime of validity of the standard Diffusive Shock Acceleration (DSA) model and, despite observed in several cases, have been poorly studied to date. This project builds upon a previous effort to interpret the observed electromagnetic radiation from astrophysical sources -- a log-parabola spectrum of energetic electrons, instead of empirical, multiple power-laws -- that explains surprisingly well the observations of the Crab Nebula over an unprecedentedly broad energy range. The project team, which based at the University of Arizona, aims to determine the physical conditions that give rise to a log-parabola spectrum, which would yield a paradigm shift in the field. The team will use the new knowledge gathered during the project to educate the general public about the physical drivers of space weather and their impacts. The research and EPO agenda of this EAGER project supports the Strategic Goals of the AGS Division in discovery, learning, diversity, and interdisciplinary research. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
文献类型	项目
条目标识符	http://119.78.100.173/C666/handle/2XK7JSWQ/73587
专题	环境与发展全球科技态势
推荐引用方式 GB/T 7714	Federico Fraschetti .EAGER: Novel Approach to Acceleration and Escape of Charged Particles at Interplanetary and Astrophysical Shock Waves.2018.