A new r-process star with low abundances of r-process elements by Frebel, Anna L., Yu, QinQin, Jacobson, Heather

“…Metal-poor stars with measurable r-process element abundances provide key clues to the production site(s) of the r-process and how its products are mixed with the surrounding medium. …”
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The R-Process Alliance: Chemodynamically Tagged Groups. II. An Extended Sample of Halo r-process-enhanced Stars by Derek Shank, Timothy C. Beers, Vinicius M. Placco, Dmitrii Gudin, Thomas Catapano, Erika M. Holmbeck, Rana Ezzeddine, Ian U. Roederer, Charli M. Sakari, Anna Frebel, Terese T. Hansen

“…Orbital characteristics based on Gaia Early Data Release 3 astrometric parameters are analyzed for ∼1700 r -process-enhanced (RPE; [Eu/Fe] > +0.3) metal-poor stars ([Fe/H] ≤ −0.8) compiled from the R -Process Alliance, the GALactic Archaeology with HERMES (GALAH) DR3 survey, and additional literature sources. …”
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The R-process Alliance: first release from the southern search for R-process-enhanced stars in the galactic halo by Hansen, Terese T., Holmbeck, Erika M., Beers, Timothy C., Placco, Vinicius M., Roederer, Ian U., Frebel, Anna, Sakari, Charli M., Simon, Joshua D., Thompson, Ian B.

“…Of those, 12 stars are strongly enhanced in heavy r-process elements (r-II), 42 stars show moderate enhancements of heavy r-process material (r-I), and 20 stars exhibit low abundances of the heavy r-process elements and higher abundances of the light r-process elements relative to the heavy ones (limited-r). …”
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The R-Process Alliance: First Magellan/MIKE Release from the Southern Search for R-process-enhanced Stars by Ezzeddine, R, Rasmussen, K, Frebel, A, Chiti, A, Hinojisa, K, Placco, VM, Ji, AP, Beers, TC, Hansen, TT, Roederer, IU, Sakari, CM, Melendez, J

“…The chemical abundance patterns of metal-poor r-process-enhanced stars provide key evidence for the dominant site(s) of the r-process and whether NSBMs are sufficiently frequent or prolific r-process sources to be responsible for the majority of r-process material in the universe. …”
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The R-Process Alliance: First Magellan/MIKE Release from the Southern Search for R-process-enhanced Stars by Ezzeddine, Rana, Rasmussen, Kaitlin, Frebel, Anna L., Chiti, Anirudh, Hinojisa, Karina, Placco, Vinicius M., Ji, Alexander P., Beers, Timothy C., Hansen, Terese T., Roederer, Ian U., Sakari, Charli M., Melendez, Jorge

“…The chemical abundance patterns of metal-poor r-process-enhanced stars provide key evidence for the dominant site(s) of the r-process and whether NSBMs are sufficiently frequent or prolific r-process sources to be responsible for the majority of r-process material in the universe. …”
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The R-Process Alliance: Fourth Data Release from the Search for R-process-enhanced Stars in the Galactic Halo by Holmbeck, EM, Hansen, TT, Beers, TC, Placco, VM, Whitten, DD, Rasmussen, KC, Roederer, IU, Ezzeddine, R, Sakari, CM, Frebel, A, Drout, MR, Simon, JD, Thompson, IB, Bland-Hawthorn, J, Gibson, BK, Grebel, EK, Kordopatis, G, Kunder, A, Meléndez, J, Navarro, JF, Reid, WA, Seabroke, G, Steinmetz, M, Watson, F, Wyse, RFĠ

“…This compilation is the fourth data release from the R-Process Alliance (RPA) search for r-process-enhanced stars and the second release based on "snapshot"high-resolution (R ∼ 30,000) spectra collected with the du Pont 2.5 m Telescope. …”
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The R-Process Alliance: Fourth Data Release from the Search for R-process-enhanced Stars in the Galactic Halo by Holmbeck, Erika M., Hansen, Terese T., Beers, Timothy C., Placco, Vinicius M, Whitten, Devin D., Rasmussen, Kaitlin C., Roederer, Ian U, Ezzeddine, Rana, Sakari, Charli M., Frebel, Anna L., Drout, Maria R., Simon, Joshua D., Thompson, Ian B., Bland-Hawthorn, Joss, Gibson, Brad K., Grebel, Eva K., Kordopatis, Georges, Kunder, Andrea, Melendez, Jorge, Navarro, Julio F., Reid, Warren A., Seabroke, George, Steinmetz, Matthias, Watson, Fred, Wyse, Rosemary F. G.

“…This compilation is the fourth data release from the R-Process Alliance (RPA) search for r-process-enhanced stars and the second release based on "snapshot"high-resolution (R ∼ 30,000) spectra collected with the du Pont 2.5 m Telescope. …”
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The R -Process Alliance: Discovery of a Low- α , r -process-enhanced Metal-poor Star in the Galactic Halo by Ezzeddine, Rana, Frebel, Anna L.

“…All rights reserved. A new moderately r-process-enhanced metal-poor star, RAVE J093730.5-062655, has been identified in the Milky Way halo as part of an ongoing survey by the R-Process Alliance. …”
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r-Process elements from magnetorotational hypernovae by Yong, D, Kobayashi, C, Da Costa, GS, Bessell, MS, Chiti, A, Frebel, A, Lind, K, Mackey, AD, Nordlander, T, Asplund, M, Casey, AR, Marino, AF, Murphy, SJ, Schmidt, BP

“…Neutron-star mergers were recently confirmed as sites of rapid-neutron-capture (r-process) nucleosynthesis1-3. However, in Galactic chemical evolution models, neutron-star mergers alone cannot reproduce the observed element abundance patterns of extremely metal-poor stars, which indicates the existence of other sites of r-process nucleosynthesis4-6. …”
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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.

“…A high-resolution spectroscopic analysis is presented for a new highly r-process-enhanced ([Eu/Fe] = 1.27, [Ba/Eu] = -0.65), very metal-poor ([Fe/H] = -2.09), retrograde halo star, RAVE J153830.9-180424, discovered as part of the R-Process Alliance survey. …”
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Actinide-rich and Actinide-poor r-process-enhanced Metal-poor Stars Do Not Require Separate r-process Progenitors by Holmbeck, Erika M., Frebel, Anna L., McLaughlin, G. C., Mumpower, Matthew R., Sprouse, Trevor M., Surman, Rebecca

“…Incorporating heavy-element signatures of metal-poor, r-process-enhanced stars into theoretical studies of r-process production can offer crucial constraints on the origin of heavy elements. …”
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The R -Process Alliance: First Release from the Northern Search for r -process-enhanced Metal-poor Stars in the Galactic Halo by Sakari, Charli M, Placco, Vinicius M, Farrell, Elizabeth M, Roederer, Ian U, Wallerstein, George, Beers, Timothy C, Ezzeddine, Rana, Frebel, Anna, Hansen, Terese, Holmbeck, Erika M, Sneden, Christopher, Cowan, John J, Venn, Kim A, Davis, Christopher Evan, Matijevič, Gal, Wyse, Rosemary FG, Bland-Hawthorn, Joss, Chiappini, Cristina, Freeman, Kenneth C, Gibson, Brad K, Grebel, Eva K, Helmi, Amina, Kordopatis, Georges, Kunder, Andrea, Navarro, Julio, Reid, Warren, Seabroke, George, Steinmetz, Matthias, Watson, Fred

“…This paper presents the detailed abundances and r-process classifications of 126 newly identified metal-poor stars as part of an ongoing collaboration, the R-Process Alliance. …”
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The R -Process Alliance: First Release from the Northern Search for r -process-enhanced Metal-poor Stars in the Galactic Halo by Sakari, Charli M, Placco, Vinicius M, Farrell, Elizabeth M, Roederer, Ian U, Wallerstein, George, Beers, Timothy C, Ezzeddine, Rana, Frebel, Anna L., Hansen, Terese, Holmbeck, Erika M, Sneden, Christopher, Cowan, John J, Venn, Kim A, Davis, Christopher Evan, Matijevič, Gal, Wyse, Rosemary FG, Bland-Hawthorn, Joss, Chiappini, Cristina, Freeman, Kenneth C, Gibson, Brad K, Grebel, Eva K, Helmi, Amina, Kordopatis, Georges, Kunder, Andrea, Navarro, Julio, Reid, Warren, Seabroke, George, Steinmetz, Matthias, Watson, Fred

“…This paper presents the detailed abundances and r-process classifications of 126 newly identified metal-poor stars as part of an ongoing collaboration, the R-Process Alliance. …”
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The R-Process Alliance: chemical abundances for a trio of R-process-enhanced stars -- one strong, one moderate, and one mild by Cain, Madelyn, Frebel, Anna, Gull, Maude, Ji, Alexander P., Placco, Vinicius M., Beers, Timothy C., Meléndez, Jorge, Ezzeddine, Rana, Casey, Andrew R., Hansen, Terese T., Roederer, Ian U., Sakari, Charli

“…J1432-4125 is among the most r-process-rich r-II stars, with [Eu/Fe] = +1.44 ± 0.11. …”
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The R-Process Alliance: Chemodynamically Tagged Groups of Halo r-process-enhanced Stars Reveal a Shared Chemical-evolution History by Gudin, Dmitrii, Shank, Derek, Beers, Timothy C, Yuan, Zhen, Limberg, Guilherme, Roederer, Ian U, Placco, Vinicius, Holmbeck, Erika M, Dietz, Sarah, Rasmussen, Kaitlin C, Hansen, Terese T, Sakari, Charli M, Ezzeddine, Rana, Frebel, Anna

“…We derive dynamical parameters for a large sample of 446 r-process-enhanced (RPE) metal-poor stars in the halo and disk systems of the Milky Way, based on data releases from the R-Process Alliance, supplemented by additional literature samples. …”
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The R-Process Alliance: Chemodynamically Tagged Groups of Halo r-process-enhanced Stars Reveal a Shared Chemical-evolution History by Gudin, Dmitrii, Shank, Derek, Beers, Timothy C., Yuan, Zhen, Limberg, Guilherme, Roederer, Ian U., Placco, Vinicius, Holmbeck, Erika M., Dietz, Sarah, Rasmussen, Kaitlin C., Hansen, Terese T., Sakari, Charli M., Ezzeddine, Rana, Frebel, Anna

“…We derive dynamical parameters for a large sample of 446 r-process-enhanced (RPE) metal-poor stars in the halo and disk systems of the Milky Way, based on data releases from the R-Process Alliance, supplemented by additional literature samples. …”
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Decision methodology : a formalization of the O.R. process / by 201491 White, Douglas John

R-process Nucleosynthesis of Subminimal Neutron Star Explosions by Chun-Ming Yip, Ming-Chung Chu, Shing-Chi Leung, Lap-Ming Lin

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Atomic masses with machine learning for the astrophysical r process by Mengke Li, Trevor M. Sprouse, Bradley S. Meyer, Matthew R. Mumpower

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The Influence of β-decay Rates on r-process Observables by Kelsey A. Lund, J. Engel, G. C. McLaughlin, M. R. Mumpower, E. M. Ney, R. Surman

Subjects: “…R-process…”
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