{"id":39956,"date":"2025-12-24T14:04:08","date_gmt":"2025-12-24T13:04:08","guid":{"rendered":"https:\/\/karmaka.de\/?p=39956"},"modified":"2025-12-24T14:04:09","modified_gmt":"2025-12-24T13:04:09","slug":"the-cai-database-26al-26mg-isotope-systematics","status":"publish","type":"post","link":"https:\/\/karmaka.de\/?p=39956","title":{"rendered":"The CAI Database: 26Al\u201326Mg Isotope Systematics<span class=\"badge-status\" style=\"background:#787878\">OPEN ACCESS<\/span>&nbsp;"},"content":{"rendered":"\n<p>Emilie T. Dunham, Ming-Chang Liu, Aman Burman, Fatima Jorge-Chavez, Danielle Leuer, Ashley K. Herbst, Fran\u00e7ois L. H. Tissot, and Kevin D. McKeegan<\/p>\n\n\n\n<p>The Astrophysical Journal Supplement Series, Volume 282, Number 1, published 22 December 2025<\/p>\n\n\n\n<p><a href=\"https:\/\/iopscience.iop.org\/article\/10.3847\/1538-4365\/ae1835\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>LINK (OPEN ACCESS)<\/strong><\/a><\/p>\n\n\n\n<p><a href=\"https:\/\/iopscience.iop.org\/article\/10.3847\/1538-4365\/ae1835\/pdf\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>PDF (OPEN ACCESS)<\/strong><\/a><\/p>\n\n\n\n<p class=\"justify-text\">&#8220;We present a publicly available calcium\u2013aluminum-rich inclusion (CAI) database that focuses on the initial 26Al\/27Al0 ratio in CAIs, designed in a way that researchers in cosmochemistry and astrophysics may find useful. To date, the database contains 497 CAIs from 75 peer-reviewed papers. The CAIs are from all chondrite groups and cover different CAI types, textures, and sizes. The database includes the paper; the host meteorite; the CAI name and type; the 26Al\/27Al0, Mg26 0 , and \u03b425Mg values and their uncertainties; the number of regression points; the maximum 27Al\/24Mg; the mean-squared weighted deviation; the CAI size; and CAI descriptions. We grouped the CAIs in different ways to discuss 26Al\/27Al0 ratio distributions with implications for the CAI formation timeline. Overall, we agree with previous authors that CAIs have a bimodal 26Al distribution: CAIs with robust isochrons (n = 151) have a median 26Al\/27Al0 = 4.8 \u00d7 10\u22125 (with a 1\u03c3 standard error of 0.1), while those with isotopic anomalies (n = 87) have a median 26Al\/27Al0 = 0.3 \u00d7 10\u22125 (with a 1\u03c3 standard error of 0.2). However, the large standard deviation of both groups (1.3 and 2.3, respectively) indicates that the 26Al\/27Al0 values scatter ignificantly within each population. CAI types and groups can have distinct 26Al\/27Al0 and Mg26 0, but the unmelted inclusions (n = 33) have the highest median 26Al\/27Al0 = 5.1 \u00d7 10\u22125 and a low median Mg26 0 = \u22120.05\u2030. We find slightly different 26Al\/27Al0 distributions between CAI chondrite types, but no differences between petrographic types or sizes. These observations can help us to understand CAI formation in the context of astrophysical models.<\/p>\n\n\n\n<p>&#8220;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Emilie T. Dunham, Ming-Chang Liu, Aman Burman, Fatima Jorge-Chavez, Danielle Leuer, Ashley K. Herbst, Fran\u00e7ois L. H. Tissot, and Kevin D. McKeegan The Astrophysical Journal Supplement Series, Volume 282, Number 1, published 22 December 2025&#8230;<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[66,68],"tags":[5830,3725,1846,1718,2403,3830,1204,1748],"_links":{"self":[{"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/39956"}],"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=39956"}],"version-history":[{"count":1,"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/39956\/revisions"}],"predecessor-version":[{"id":39957,"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/39956\/revisions\/39957"}],"wp:attachment":[{"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=39956"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=39956"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=39956"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}