{"id":12545,"date":"2017-05-24T06:55:14","date_gmt":"2017-05-24T04:55:14","guid":{"rendered":"http:\/\/karmaka.de\/?p=12545"},"modified":"2017-05-24T06:55:14","modified_gmt":"2017-05-24T04:55:14","slug":"stellar-origin-of-15n-rich-presolar-sic-grains-of-type-ab-supernovae-with-explosive-hydrogen-burning","status":"publish","type":"post","link":"https:\/\/karmaka.de\/?p=12545","title":{"rendered":"Stellar origin of 15N-rich presolar SiC grains of type AB: supernovae with explosive hydrogen burning<span class=\"badge-status\" style=\"background:#787878\">OPEN ACCESS<\/span>&nbsp;"},"content":{"rendered":"<p>Nan Liu, Larry R. Nittler, Marco Pignatari, Conel M. O&#8217;D. Alexander, Jianhua Wang<\/p>\n<p>The Astrophysical Journal Letters<\/p>\n<p><a href=\"https:\/\/arxiv.org\/ftp\/arxiv\/papers\/1705\/1705.08222.pdf\" target=\"_blank\"><strong>PDF (OPEN ACCESS)<\/strong><\/a><\/p>\n<p>&#8220;We report C, N, and Si isotopic data for 59 highly 13C-enriched presolar submicron- to micron-sized SiC grains from the Murchison meteorite, including eight putative nova grains (PNGs) and 29 15N-rich (14N\/15N<=solar) AB grains, and their Mg-Al, S, and Ca-Ti isotope data when available. These 37 grains are enriched in 13C, 15N and 26Al with the PNGs showing more extreme enhancements. The 15N-rich AB grains show systematically higher 26Al and 30Si excesses than the 14N-rich AB grains. Thus, we propose to divide the AB grains into groups 1 (14N\/15N<solar) and 2 (14N\/15N>=solar). For the first time, we have obtained both S and Ti isotopic data for five AB1 grains and one PNG, and found 32S and\/or 50Ti enhancements. Interestingly, one AB1 grain had the largest 32S and 50Ti excesses, strongly suggesting a neutron-capture nucleosynthetic origin of the 32S excess and thus the initial presence of radiogenic 32Si (t1\/2=153 yr). More importantly, we found that the 15N and 26Al excesses of AB1 grains form a trend that extends to the region in the N-Al isotope plot occupied by C2 grains, strongly indicating a common stellar origin for both AB1 and C2 grains. Comparison of supernova models with the AB1 and C2 grain data indicates that these grains came from SNe that experienced H ingestion into the He\/C zones of their progenitors. &#8220;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Nan Liu, Larry R. Nittler, Marco Pignatari, Conel M. O&#8217;D. Alexander, Jianhua Wang The Astrophysical Journal Letters PDF (OPEN ACCESS) &#8220;We report C, N, and Si isotopic data for 59 highly 13C-enriched presolar submicron- to&#8230;<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[9,18,76],"tags":[107,1853,539],"_links":{"self":[{"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/12545"}],"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=12545"}],"version-history":[{"count":1,"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/12545\/revisions"}],"predecessor-version":[{"id":12546,"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/12545\/revisions\/12546"}],"wp:attachment":[{"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=12545"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=12545"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=12545"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}