Characterizing r-Process Sites through Actinide Production by Holmbeck, Erika M, Surman, Rebecca, Frebel, Anna, McLaughlin, GC, Mumpower, Matthew R, Sprouse, Trevor M, Kawano, Toshihiko, Vassh, Nicole, Beers, Timothy C

“…Of the variations in the elemental abundance patterns of stars enhanced with r-process elements, the variation in the relative actinide-To-lanthanide ratio is among the most significant. …”
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From Actinides to Zinc: Using the Full Abundance Pattern of the Brightest Star in Reticulum II to Distinguish between Different by Ji, Alexander P., Frebel, Anna L.

“…The high signal-to-noise allows us to determine the abundances of 41 elements, including the radioactive actinide element Th and first ever detections of third r-process peak elements (Os and Ir) in a star outside the Milky Way. …”
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The R-Process Alliance: 2MASS J09544277+5246414, the most actinide-enhanced R-II star known by Frebel, Anna

“…Smith 2.7 m telescope, this star is the first confirmed actinide-boost star found by RPA efforts. With an enhancement of [Th/Eu] = +0.37, 2MASS J09544277+5246414 is also the most actinide-enhanced r-II star yet discovered, and only the sixth metal-poor star with a measured uranium abundance ([U/Fe] = +1.40). …”
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Statistical Features of the Thermal Neutron Capture Cross Sections by Hussein, M. S., Carlson, B. V., Kerman, Arthur Kent

“…We lend support to the idea that this phenomenon is random in nature and is similar to what we have learned from the study of parity violation in the actinide region. The idea of statistical doorways is advanced as a unified concept in the delineation of large numbers in the nuclear world. …”
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RAVE J203843.2–002333: The First Highly R-process-enhanced Star Identified in the RAVE Survey by Placco, Vinicius M., Holmbeck, Erika M., Beers, Timothy C., Surman, Rebecca A., Points, Sean D., Kaleida, Catherine C., Hansen, Terese T., Sakari, Charli M., Casey, Andrew R., Frebel, Anna L., Ji, Alexander Pung, Ezzeddine, Rana

“…The derived chemical abundance pattern exhibits good agreement with those of other known highly r-process-enhanced stars, and evidence suggests that it is not an actinide-boost star. Age estimates were calculated using U/X abundance ratios, yielding a mean age of 13.0 ± 1.1 Gyr.…”
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The r-process Pattern of a Bright, Highly r -process-enhanced Metal-poor Halo Star at [Fe/H ] ~ -2 by Sakari, Charli M., Placco, Vinicius M., Hansen, Terese, Holmbeck, Erika M., Beers, Timothy C., Roederer, Ian U., Venn, Kim A., Wallerstein, George, Davis, Christopher Evan, Farrell, Elizabeth M., Yong, David, Frebel, Anna L.

“…As with many other r-process-enhanced stars, J1538-1804's r-process pattern matches that of the Sun for elements between the first, second, and third peaks, and does not exhibit an actinide boost. Cosmo-chronometric age-dating reveals the r-process material to be quite old. …”
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Reconstructing Masses of Merging Neutron Stars from Stellar r-process Abundance Signatures by Holmbeck, Erika M, Frebel, Anna, McLaughlin, GC, Surman, Rebecca, Fernández, Rodrigo, Metzger, Brian D, Mumpower, Matthew R, Sprouse, TM

“…We use ratios of elements typically associated with the limited-<jats:italic>r</jats:italic>-process and the actinide region to those in the lanthanide region (i.e., Zr/Dy and Th/Dy) to probe the NS masses of the progenitor merger. …”
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