Evidence in meteorites for an active early sun

Abstract

view Abstract Citations (57) References (26) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Evidence in Meteorites for an Active Early Sun Caffe, M. W. ; Hohenberg, C. M. ; Swindle, T. D. ; Goswami, J. N. Abstract High-sensitivity noble gas mass-spectrometric analyses of meteorite grains having solar flare heavy ion tracks show large enrichments of spallation-produced Ne-21 and Ar-38 when compared to nonirradiated grains from the same meteorite. The enhanced spallation effects in the irradiated grains are due to irradiation by energetic protons early in the history of the solar system, before compaction of the host meteorite. They require a proton fluence (E greater than 10 MeV) of 10 to the 16th to 10 to the 18th/cu cm. These results are best explained by solar flare irradiation in the early solar system with a proton flux several orders of magnitude higher than contemporary solar flares. The Ne isotopic structure suggests a harder energy spectrum than is characteristic of contemporary flares. These observations provide direct evidence for an active early (T Tauri) sun. Publication: The Astrophysical Journal Pub Date: February 1987 DOI: 10.1086/184826 Bibcode: 1987ApJ...313L..31C Keywords: Meteoritic Composition; Particle Tracks; Solar Flares; Solar System; Spallation; Argon Isotopes; Neon Isotopes; Solar Activity; METEORITES; SUN; RARE GASES; SPECTROMETRY; SAMPLES; METEORITE; GRAINS; SOLAR FLARES; ION TRACKS; ENRICHMENT; SPALLATION; NEON 21; ARGON 38; IRRADIATION; PROTONS; FLUX; ORIGIN; SOURCE; ISOTOPES; EXPERIMENTS; LABORATORY STUDIES; PROCEDURE; EXPOSURE AGE; CONCENTRATION; MURCHISON; KAPOETA; WESTON; FAYETTEVILLE; CARBONACEOUS CHONDRITES; ACHONDRITES; H CHONDRITES; STONY METEORITES; COSMIC RAYS; Lunar and Planetary Exploration; Meteorites; METEORS AND METEORITES; SOLAR SYSTEM: GENERAL; SUN: ACTIVITY; SUN: GENERAL; SUN: FLARES full text sources ADS |