Isotopic 32S/33S ratio as a diagnostic of presolar grains from novae
نویسندگان
چکیده
a Departament de Física i Enginyeria Nuclear, Universitat Politècnica de Catalunya, EUETIB, E-08036 Barcelona, Spain b Institut d’Estudis Espacials de Catalunya (IEEC), E-08034 Barcelona, Spain c Physik Department E12, Technische Universität München, D-85748 Garching, Germany d Maier-Leibnitz-Laboratorium der Münchner Universitäten (MLL), D-85748 Garching, Germany e Department of Physics, Central Michigan University, Mount Pleasant, MI 48859, USA f Fakultät für Physik, Ludwig-Maximilians-Universität München, D-85748 Garching, Germany g TRIUMF, Vancouver, BC, V6T 2A3, Canada
منابع مشابه
Presolar Grains from Novae
We report the discovery of five SiC grains and one graphite grain isolated from the Murchison carbonaceous meteorite whose major-element isotopic compositions indicate an origin in nova explosions. The grains are characterized by low C/C (4-9) and N/N (5-20) ratios, large excesses in Si (Si/Si ratios range to 2.1 times solar) and high Al/Al ratios. These isotopic signatures are theoretically pr...
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Introduction: Last year we reported the successful isolation of presolar graphite from Orgueil and presented C, N, O and Si isotopic ratios on individual graphite grains from seven density fractions, with grain sizes > 1μm (Table 1) [1, 2]. Except for fractions ORG1b and 1h, all fractions analyzed were found to contain presolar carbonaceous grains that are morphologically and isotopically simil...
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Presolar graphite is the carrier of Ne-E(L) and most 22 Ne in Ne-E(L) had long been attributed to radiogenic decay of 22 Na from novae. Of presolar graphite grains with a range of density (1.6-2.2g/cm 3 ), low-density graphite grains extracted from the Murchison meteorite are characterized by 18 O excesses and Si isotopic anomalies and are believed to have formed in supernova ejecta. From noble...
متن کاملIsotopic analysis of presolar graphite grains from Orgueil
We report the successful isolation and isotopic analysis of presolar graphite grains from the Orgueil CI chondrite. Isotopic measurements were made on seven density fractions, with grain sizes >1 lm: ORG1b (1.59–1.67 g cm ), 1c (1.67–1.75 g cm ), 1d (1.75– 1.92 g cm ), 1f (2.02–2.04 g cm ), 1g (2.04–2.12 g cm ), 1h (2.12–2.16 g cm ) and 1i (2.16–2.30 g cm ). We measured C, N, O, and Si isotopes...
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