{"id":32267,"date":"2023-02-01T19:00:22","date_gmt":"2023-02-01T18:00:22","guid":{"rendered":"https:\/\/karmaka.de\/?p=32267"},"modified":"2023-02-01T19:00:23","modified_gmt":"2023-02-01T18:00:23","slug":"new-constraints-for-supernova-models-from-presolar-silicon-carbide-x-grains-with-very-high-26al-27al-ratios","status":"publish","type":"post","link":"https:\/\/karmaka.de\/?p=32267","title":{"rendered":"New Constraints for Supernova Models from Presolar Silicon Carbide X Grains with Very High 26Al\/27Al Ratios<span class=\"badge-status\" style=\"background:#787878\">OPEN ACCESS<\/span>&nbsp;"},"content":{"rendered":"\n<p>Peter Hoppe, Jan Leitner, Marco Pignatari, and Sachiko Amari<\/p>\n\n\n\n<p>The Astrophysical Journal Letters, Volume 943, Number 2<\/p>\n\n\n\n<p><a href=\"https:\/\/iopscience.iop.org\/article\/10.3847\/2041-8213\/acb157\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>LINK (OPEN ACCESS)<\/strong><\/a><br><a href=\"https:\/\/iopscience.iop.org\/article\/10.3847\/2041-8213\/acb157\/pdf\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>PDF (OPEN ACCESS)<\/strong><\/a><\/p>\n\n\n\n<p class=\"justify-text\">&#8220;We report C, N, Mg-Al, Si, and S isotope data of six 1\u20133\u03bcm-sized SiC grains of Type X from the Murchison CM2 chondrite, believed to have formed in the ejecta of core-collapse supernova (CCSN) explosions. Their C, N, and Si isotopic compositions are fully compatible with previously studied X grains. Magnesium is essentially monoisotopic 26Mg which gives clear evidence for the decay of radioactive 26Al. Inferred initial 26Al\/27Al ratios are between 0.6 and 0.78 which is at the upper end of previously observed ratios of X grains. Contamination with terrestrial or solar system Al apparently is low or absent, which makes the X grains from this study particularly interesting and useful for a quantitative comparison of Al isotope data with predictions from supernova models. The consistently high 26Al\/27Al ratios observed here may suggest that the lower 26Al\/27Al ratios of many X grains from the literature are the result of significant Al contamination and in part also of an improper quantification of 26Al. The real dispersion of 26Al\/27Al ratios in X grains needs to be explored by future studies. The high observed 26Al\/27Al ratios in this work provide a crucial constraint for the production of 26Al in CCSN models. We explored different CCSN models, including both &#8220;classical&#8221; and H ingestion CCSN models. It is found that the classical models cannot account for the high 26Al\/27Al ratios observed here; in contrast, H ingestion models are able to reproduce the 26Al\/27Al ratios along with C, N, and Si isotopic ratios reasonably well.&#8221;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Peter Hoppe, Jan Leitner, Marco Pignatari, and Sachiko Amari The Astrophysical Journal Letters, Volume 943, Number 2 LINK (OPEN ACCESS)PDF (OPEN ACCESS) &#8220;We report C, N, Mg-Al, Si, and S isotope data of six 1\u20133\u03bcm-sized&#8230;<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[9,18,76],"tags":[238,448,3273,2536,105,6474,107,125,1853,1750,539,424,2323],"_links":{"self":[{"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/32267"}],"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=32267"}],"version-history":[{"count":1,"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/32267\/revisions"}],"predecessor-version":[{"id":32268,"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/32267\/revisions\/32268"}],"wp:attachment":[{"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=32267"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=32267"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=32267"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}