气候变化领域集成服务门户(CCPortal): Lifetimes of interstellar dust from cosmic ray exposure ages of presolar silicon carbide

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DOI	10.1073/pnas.1904573117
	Lifetimes of interstellar dust from cosmic ray exposure ages of presolar silicon carbide
	Heck P.R.; Greer J.; Kööp L.; Trappitsch R.; Gyngard F.; Busemann H.; Maden C.; Ávila J.N.; Davis A.M.; Wieler R.
发表日期	2020
ISSN	0027-8424
起始页码	1884
结束页码	1889
卷号	117 期号:4
英文摘要	We determined interstellar cosmic ray exposure ages of 40 large presolar silicon carbide grains extracted from the Murchison CM2 meteorite. Our ages, based on cosmogenic Ne-21, range from 3.9 ± 1.6 Ma to ∼3 ± 2 Ga before the start of the Solar System ∼4.6 Ga ago. A majority of the grains have interstellar lifetimes of <300 Ma, which is shorter than theoretical estimates for large grains. These grains condensed in outflows of asymptotic giant branch stars <4.9 Ga ago that possibly formed during an episode of enhanced star formation ∼7 Ga ago. A minority of the grains have ages >1 Ga. Longer lifetimes are expected for large grains. We determined that at least 12 of the analyzed grains were parts of aggregates in the interstellar medium: The large difference in nuclear recoil loss of cosmic ray spallation products 3He and 21Ne enabled us to estimate that the irradiated objects in the interstellar medium were up to 30 times larger than the analyzed grains. Furthermore, we estimate that the majority of the grains acquired the bulk of their cosmogenic nuclides in the interstellar medium and not by exposure to an enhanced particle flux of the early active sun. © 2020 National Academy of Sciences. All rights reserved.
英文关键词	Cosmochemistry; Exposure age dating; Interstellar dust; Meteorites; Presolar grains
语种	英语
scopus关键词	helium; helium 3; neon; neon 21; silicon carbide; unclassified drug; Article; astronomy; chemistry; controlled study; cosmic radiation; cosmochemistry; cosmos; dust; interstellar dust; irradiation; particle size; priority journal; radiation exposure; radiometric dating; volume
来源期刊	Proceedings of the National Academy of Sciences of the United States of America
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/160320
作者单位	Heck, P.R., Robert A. Pritzker Center for Meteoritics and Polar Studies, Field Museum of Natural History, Chicago, IL 60605, United States, Chicago Center for Cosmochemistry, University of Chicago, Chicago, IL 60637, United States, Department of the Geophysical Sciences, University of Chicago, Chicago, IL 60637, United States; Greer, J., Robert A. Pritzker Center for Meteoritics and Polar Studies, Field Museum of Natural History, Chicago, IL 60605, United States, Chicago Center for Cosmochemistry, University of Chicago, Chicago, IL 60637, United States, Department of the Geophysical Sciences, University of Chicago, Chicago, IL 60637, United States; Kööp, L., Robert A. Pritzker Center for Meteoritics and Polar Studies, Field Museum of Natural History, Chicago, IL 60605, United States, Chicago Center for Cosmochemistry, University of Chicago, Chicago, IL 60637, United States, Department of the Geophysical Sciences, University of Chicago, Chicago, IL 60637, United States; Trappitsch, R., Nuclear and...
推荐引用方式 GB/T 7714	Heck P.R.,Greer J.,Kööp L.,et al. Lifetimes of interstellar dust from cosmic ray exposure ages of presolar silicon carbide[J],2020,117(4).
APA	Heck P.R..,Greer J..,Kööp L..,Trappitsch R..,Gyngard F..,...&Wieler R..(2020).Lifetimes of interstellar dust from cosmic ray exposure ages of presolar silicon carbide.Proceedings of the National Academy of Sciences of the United States of America,117(4).
MLA	Heck P.R.,et al."Lifetimes of interstellar dust from cosmic ray exposure ages of presolar silicon carbide".Proceedings of the National Academy of Sciences of the United States of America 117.4(2020).