{"id":30419,"date":"2022-04-04T13:39:56","date_gmt":"2022-04-04T12:39:56","guid":{"rendered":"https:\/\/karmaka.de\/?p=30419"},"modified":"2022-04-04T13:39:57","modified_gmt":"2022-04-04T12:39:57","slug":"hydrogen-burning-of-29si-and-its-impact-on-presolar-stardust-grains-from-classical-novae","status":"publish","type":"post","link":"https:\/\/karmaka.de\/?p=30419","title":{"rendered":"Hydrogen Burning of 29Si and Its Impact on Presolar Stardust Grains from Classical Novae<span class=\"badge-status\" style=\"background:#787878\">OPEN ACCESS<\/span>&nbsp;"},"content":{"rendered":"\n<p>Lori Downen, Christian Iliadis, Art Champagne, Thomas Clegg, Alain Coc, and Jordi Jos\u00e9<\/p>\n\n\n\n<p>The Astrophysical Journal, Volume 928, Number 2<\/p>\n\n\n\n<p><a href=\"https:\/\/iopscience.iop.org\/article\/10.3847\/1538-4357\/ac582b\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>LINK (OPEN ACCESS)<\/strong><\/a><br><a href=\"https:\/\/iopscience.iop.org\/article\/10.3847\/1538-4357\/ac582b\/pdf\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>PDF (OPEN ACCESS)<\/strong><\/a><\/p>\n\n\n\n<p class=\"justify-text\">&#8220;Presolar stardust grains found in primitive meteorites are believed to retain the isotopic composition of stellar outflows at the time of grain condensation. Therefore, laboratory measurements of their isotopic ratios represent sensitive probes for investigating open questions related to stellar evolution, stellar explosions, nucleosynthesis, mixing mechanisms, dust formation, and galactic chemical evolution. For a few selected presolar grains, classical novae have been discussed as a potential source. For SiC, silicate, and graphite presolar grains, the association is based on the observation of small N(12C)\/N(13C) and N(14N)\/N(15N) number abundance ratios compared to solar values, and abundance excesses in 30Si relative to 29Si, as previously predicted by models of classical novae. We report on a direct measurement of the 29Si(p,\u03b3)30P reaction, which strongly impacts simulated \u03b429Si values from classical novae. Our new experimental 29Si(p,\u03b3)30P thermonuclear reaction rate differs from previous results by up to 50% in the classical nova temperature range (T= 100\u2013400 MK), while the rate uncertainty is reduced by up to a factor of 3. Using our new reaction rate in Monte Carlo reaction network and hydrodynamic simulations of classical novae, we estimate \u03b429Si values with much reduced uncertainties. Our results establish \u03b429Si values measured in presolar grains as a sensitive probe for assessing their classical nova paternity. We also demonstrate that \u03b430Si values from nova simulations are currently not a useful diagnostic tool unless the large uncertainty of the 30P(p,\u03b3)31S reaction rate can be significantly reduced.&#8221;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Lori Downen, Christian Iliadis, Art Champagne, Thomas Clegg, Alain Coc, and Jordi Jos\u00e9 The Astrophysical Journal, Volume 928, Number 2 LINK (OPEN ACCESS)PDF (OPEN ACCESS) &#8220;Presolar stardust grains found in primitive meteorites are believed to&#8230;<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[76],"tags":[6252,125,1853],"_links":{"self":[{"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/30419"}],"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=30419"}],"version-history":[{"count":1,"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/30419\/revisions"}],"predecessor-version":[{"id":30420,"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/30419\/revisions\/30420"}],"wp:attachment":[{"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=30419"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=30419"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=30419"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}