{"id":5227,"date":"2015-07-15T16:37:13","date_gmt":"2015-07-15T14:37:13","guid":{"rendered":"http:\/\/karmaka.de\/?p=5227"},"modified":"2015-07-15T16:53:51","modified_gmt":"2015-07-15T14:53:51","slug":"new-constraints-on-the-abundances-of-silicate-and-oxide-stardust-from-supernovae-in-the-acfer-094-meteorite","status":"publish","type":"post","link":"https:\/\/karmaka.de\/?p=5227","title":{"rendered":"New Constraints on the Abundances of Silicate and Oxide Stardust from Supernovae in the Acfer 094 Meteorite"},"content":{"rendered":"<p>Peter Hoppe, Jan Leitner, and J\u00e1nos Kodol\u00e1nyi<\/p>\n<p>ApJ 808 L9. doi:10.1088\/2041-8205\/808\/1\/L9<\/p>\n<p><a href=\"http:\/\/iopscience.iop.org\/2041-8205\/808\/1\/L9\/article;jsessionid=3BBD5D126625EA2DF93D309E4EB6ACA5.c5\" target=\"_blank\"><strong>LINK<\/strong><\/a><\/p>\n<div class=\"su-quote su-quote-style-default\"><div class=\"su-quote-inner su-u-clearfix su-u-trim\">We studied about 5000 \u03bcm2 of fine-grained matrix material in the Acfer 094 meteorite by high-resolution (nominal 50 nm) NanoSIMS ion imaging for the presence of O-rich presolar (stardust) grains. This approach permits identifying presolar grains down to <100 nm in size, compared to >150 nm in lower-resolution (nominal 100 nm) ion imaging surveys. The number density of identified presolar grains is a about a factor of two to three higher than what was found by lower-resolution ion imaging studies. The abundances of grains of O isotope Group 3 and 4 are higher than previously found. None of the presolar grains shows the strong enrichments in 16O expected from model predictions for the majority of supernova (SN) grains. Other potential O-rich SN grains, the Group 4 and some of the Group 3 grains, make up 33% by number and 19% by mass. This is clearly higher than the ~10% (by number) inferred before and the 5% (by mass) estimated by a model for stellar dust in the interstellar medium. Our work shows that O-rich SN grains might be more abundant among the population of presolar grains in primitive solar system materials than currently thought, even without the 16O-rich grains as predominantly expected from SN models.<\/div><\/div>\n","protected":false},"excerpt":{"rendered":"<p>Peter Hoppe, Jan Leitner, and J\u00e1nos Kodol\u00e1nyi ApJ 808 L9. doi:10.1088\/2041-8205\/808\/1\/L9 LINK<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[9,58,76,335],"tags":[568,1853,1712],"_links":{"self":[{"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/5227"}],"collection":[{"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=5227"}],"version-history":[{"count":1,"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/5227\/revisions"}],"predecessor-version":[{"id":5228,"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/5227\/revisions\/5228"}],"wp:attachment":[{"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=5227"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=5227"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=5227"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}