R-process enrichment from a single event in an ancient dwarf galaxy by Simon, Joshua D., Ji, Alexander Pung, Frebel, Anna L., Chiti, Anirudh

“…The smaller, chemically simpler, and more ancient ultrafaint dwarf galaxies assembled shortly after the first stars formed, and are ideal systems with which to study nucleosynthesis events such as the r-process. Reticulum II is one such galaxy. …”
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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.

“…We compare the detailed abundance pattern to predictions from nucleosynthesis calculations of NSMs and magnetorotationally driven jet supernovae, finding that nuclear physics uncertainties dominate over astrophysical uncertainties. …”
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The R-process alliance: discovery of the first metal-poor star with a combined r- and s-process element signature by Gull, Maude, Frebel, Anna, Cain, Madelyn G., Ji, Alexander P., Ezzeddine, Rana

“…Thorium is also detected, as expected from an r-process origin, as Th is not produced in the s-process. We employ nucleosynthesis model predictions that take an initial r-process enhancement into account, and then determine the mass transfer of carbon and s-process material from a putative more massive companion onto the observed star. …”
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Dynamically Tagged Groups of Very Metal-poor Halo Stars from the HK and Hamburg/ESO Surveys by Limberg, Guilherme, Rossi, Silvia, Beers, Timothy C, Perottoni, Hélio D, Pérez-Villegas, Angeles, Santucci, Rafael M, Abuchaim, Yuri, Placco, Vinicius M, Lee, Young Sun, Christlieb, Norbert, Norris, John E, Bessell, Michael S, Ryan, Sean G, Wilhelm, Ronald, Rhee, Jaehyon, Frebel, Anna

“…Taken as a whole, these results are consistent with ultra-faint and/or dwarf spheroidal galaxies as birth environments in which r-process nucleosynthesis took place, and then were disrupted by the Milky Way.…”
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THE BEST AND BRIGHTEST METAL-POOR STARS by Casey, Andrew R., Schlaufman, Kevin C

“…The chemical abundances of large samples of extremely metal-poor (EMP) stars can be used to investigate metal-free stellar populations, supernovae, and nucleosynthesis as well as the formation and galactic chemical evolution of the Milky Way and its progenitor halos. …”
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The VLT-FLAMES Tarantula Survey: XXV. Surface nitrogen abundances of O-type giants and supergiants by Grin, N, Ramírez-Agudelo, O, de Koter, A, Sana, H, Puls, J, Brott, I, Crowther, P, Dufton, P, Evans, C, Gräfener, G, Herrero, A, Langer, N, Lennon, D, van Loon, J, Markova, N, , d, Najarro, F, Schneider, F, Taylor, W, Tramper, F, Vink, J, Walborn, N

“…Theoretically, rotation-induced chemical mixing in massive stars has far reaching evolutionary consequences, affecting the sequence of morphological phases, lifetimes, nucleosynthesis, and supernova characteristics. Aims. …”

NINE-YEAR WILKINSON MICROWAVE ANISOTROPY PROBE (WMAP) OBSERVATIONS: FINAL MAPS AND RESULTS by Bennett, C, Larson, D, Weiland, J, Jarosik, N, Hinshaw, G, Odegard, N, Smith, K, Hill, R, Gold, B, Halpern, M, Komatsu, E, Nolta, MR, Page, L, Spergel, D, Wollack, E, Dunkley, J, Kogut, A, Limon, M, Meyer, S, Tucker, G, Wright, E

“…When WMAP data are combined with finer scale CMB, baryon acoustic oscillation, and Hubble constant measurements, we find that big bang nucleosynthesis is well supported and there is no compelling evidence for a non-standard number of neutrino species (N eff = 3.84 ± 0.40). …”

From SuperTIGER to TIGERISS by B. F. Rauch, W. V. Zober, Q. Abarr, Y. Akaike, W. R. Binns, R. F. Borda, R. G. Bose, T. J. Brandt, D. L. Braun, J. H. Buckley, N. W. Cannady, S. Coutu, R. M. Crabill, P. F. Dowkontt, M. H. Israel, M. Kandula, J. F. Krizmanic, A. W. Labrador, W. Labrador, L. Lisalda, J. V. Martins, M. P. McPherson, R. A. Mewaldt, J. G. Mitchell, J. W. Mitchell, S. A. I. Mognet, R. P. Murphy, G. A. de Nolfo, S. Nutter, M. A. Olevitch, N. E. Osborn, I. M. Pastrana, K. Sakai, M. Sasaki, S. Smith, H. A. Tolentino, N. E. Walsh, J. E. Ward, D. Washington, A. T. West, L. P. Williams

“…Extended single-element resolution UHGCR measurements through <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msub><mrow></mrow><mn>82</mn></msub></semantics></math></inline-formula>Pb will cover elements produced in s-process and r-process neutron capture nucleosynthesis, adding to the multi-messenger effort to determine the relative contributions of supernovae (SNe) and Neutron Star Merger (NSM) events to the r-process nucleosynthesis product content of the galaxy.…”
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Collapse of Rotating Massive Stars Leading to Black Hole Formation and Energetic Supernovae by Sho Fujibayashi, Yuichiro Sekiguchi, Masaru Shibata, Shinya Wanajo

“…The explosion energy is still increasing at the end of the simulations with a rate of >10 ^50 erg s ^−1 , and thus, it may reach ∼10 ^52 erg. A nucleosynthesis calculation shows that the mass of ^56 Ni amounts to ≳0.1 M _⊙ , which, together with the high explosion energy, may satisfy the required amount for broad-lined type Ic supernovae. …”
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Enhanced production of 60Fe in massive stars by A. Spyrou, D. Richman, A. Couture, C. E. Fields, S. N. Liddick, K. Childers, B. P. Crider, P. A. DeYoung, A. C. Dombos, P. Gastis, M. Guttormsen, K. Hermansen, A. C. Larsen, R. Lewis, S. Lyons, J. E. Midtbø, S. Mosby, D. Muecher, F. Naqvi, A. Palmisano-Kyle, G. Perdikakis, C. Prokop, H. Schatz, M. K. Smith, C. Sumithrarachchi, A. Sweet

“…Among the material ejected, long-lived radioisotopes, such as 60Fe (iron) and 26Al (aluminum), offer unique signs of active nucleosynthesis in our galaxy. There is a long-standing discrepancy between the observed 60Fe/26Al ratio by γ-ray telescopes and predictions from supernova models. …”
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Experimental study of 37Cl(α,n)40K reaction in order to constrain the reaction rate of destruction of 40K in stars by Dimitrakopoulos Nikolaos, Perdikakis Georgios, Tsintari Pelagia, Brune Carl R., Massey Thomas N., Meisel Zach, Voinov Alexander, Ingram David C., Gastis Panos, Jones-Alberty Yenuel, Subedi Shiv K., Warren Justin, Brandenburg Kristyn H., Singh Nisha, Ulbrich Lauren P.

“…This study aims to constrain the 40K(n,α)37Cl reaction rate, one of the two major destruction paths of 40K in stellar nucleosynthesis,by measuring the reverse reaction 37Cl(α,n)40K and applying the principle of detailed balance as we have done before for the 40K (40K(n,p)40Ar reaction rate) [2]. …”
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Thorium in Kilonova Spectra: Exploring the Heaviest Detectable Element by Nanae Domoto, Shinya Wanajo, Masaomi Tanaka, Daiji Kato, Kenta Hotokezaka

“…Kilonova spectra provide us with direct information about rapid neutron-capture nucleosynthesis ( r -process) in neutron star (NS) mergers. …”
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Proposed Lunar Measurements of r-Process Radioisotopes to Distinguish the Origin of Deep-sea 244Pu by Xilu Wang, Adam M. Clark, John Ellis, Adrienne F. Ertel, Brian D. Fields, Brian J. Fry, Zhenghai Liu, Jesse A. Miller, Rebecca Surman

“…. ^244 Pu is among the heaviest r -process products, and we consider whether it was created in supernovae, which is disfavored by nucleosynthesis simulations, or in an earlier kilonova event that seeded the nearby interstellar medium with ^244 Pu that was subsequently swept up by the supernova debris. …”
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Imprint of pairing correlation in (n, γ) and Maxwellian-averaged cross sections of an odd-odd 166Ho nucleus by Le Tan Phuc, Tran Vu Dong, Nguyen Dinh Dang, Bui Minh Hue, Le Thi Quynh Huong, Balaram Dey, Nguyen Ngoc Anh, Nguyen Quang Hung

“…Utilizing the obtained NLD and RSF, we predict the 165Ho(n,γ)166Ho and Maxwellian-averaged cross sections, which exhibit remarkable agreement with all the available experimental data from the Experimental Nuclear Reaction Data and Karlsruhe Astrophysical Database of Nucleosynthesis in Stars. These results reflect the imprint of the pairing correlation on those quantities.…”
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Detection of Metal Enrichment by SN 2011jm in NGC 4809 by Yulong Gao, Qiusheng Gu, Ping Zhou, Yong Shi, Xiangdong Li

“…Cosmic metals are believed to originate from stellar and supernovae (SNe) nucleosynthesis, dispersed into the interstellar medium (ISM) through stellar winds and supernova explosions. …”
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SD 1313–0019: ANOTHER SECOND-GENERATION STAR WITH [Fe/H] = −5.0, OBSERVED WITH THE MAGELLAN TELESCOPE by Chiti, Anirudh, Placco, Vinicius M., Frebel, Anna L., Ji, Alexander Pung, Jacobson, Heather

“…This ever-increasing population of carbon-rich, iron-deficient stars can potentially constrain nucleosynthesis in Population III stars and their supernova explosions, the formation mechanisms of the first low-mass stars, and the nature of the first galaxies.…”
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THE CHEMICAL ABUNDANCES OF STARS IN THE HALO (CASH) PROJECT. III. A NEW CLASSIFICATION SCHEME FOR CARBON-ENHANCED METAL-POOR STARS WITH s-PROCESS ELEMENT ENHANCEMENT by Hollek, Julie K., Placco, Vinicius M., Karakas, Amanda I., Shetrone, Matthew, Sneden, Christopher, Christlieb, Norbert, Frebel, Anna L.

“…Based on abundance comparisons with asymptotic giant branch (AGB) star nucleosynthesis models, we suggest a new physically motivated origin and classification scheme for CEMP-s stars and the still poorly understood CEMP-r/s. …”
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Energy-Momentum Squared Gravity: A Brief Overview by Ricardo A. C. Cipriano, Nailya Ganiyeva, Tiberiu Harko, Francisco S. N. Lobo, Miguel A. S. Pinto, João Luís Rosa

“…These effects dominate under high-energy conditions, enabling EMSG to potentially address unresolved issues in General Relativity (GR), such as the initial singularity and aspects of big-bang nucleosynthesis in certain models. The theory’s explicit non-minimal coupling between matter and geometry leads to the non-conservation of the energy-momentum tensor, which prompts the investigation of cosmological scenarios through the framework of irreversible thermodynamics of open systems. …”
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Magnetized Outflows from Short-lived Neutron Star Merger Remnants Can Produce a Blue Kilonova by Sanjana Curtis, Pablo Bosch, Philipp Mösta, David Radice, Sebastiano Bernuzzi, Albino Perego, Roland Haas, Erik Schnetter

“…The simulation uses an M1 neutrino transport scheme to track neutrino–matter interactions and is well suited to studying the resulting nucleosynthesis and kilonova emission. A magnetized wind is driven from the remnant and ejects neutron-rich material at a quasi-steady-state rate of 0.8 × 10 ^−1 M _⊙ s ^−1 . …”
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AEOS: Star-by-star Cosmological Simulations of Early Chemical Enrichment and Galaxy Formation by Kaley Brauer, Andrew Emerick, Jennifer Mead, Alexander P. Ji, John H. Wise, Greg L. Bryan, Mordecai-Mark Mac Low, Benoit Côté, Eric P. Andersson, Anna Frebel

“…These simulations underscore the importance of chemical abundance patterns in ancient stars as vital probes of early nucleosynthesis, star formation histories, and galaxy formation. …”
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