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1. Measurements of ¹⁸ O ¹⁸ O and ¹⁷ O ¹⁸ O in the atmosphere and the role of isotope-exchange reactions: ¹⁸ O ¹⁸ O AND ¹⁷ O ¹⁸ O IN THE ATMOSPHERE

   https://doi.org/10.1029/2012JD017992  

   Yeung, Laurence Y.; Young, Edward D.; Schauble, Edwin A. (September 2012, Journal of Geophysical Research: Atmospheres)
2. ¹⁶ O +  ¹⁶ O fusion at sub-coulomb energies

   https://doi.org/10.1088/1361-6471/ae1248  

   Islam, M Sujan; Freer, M; Merchant, A C; Wiescher, Michael C; Thompson, Ian J; Basunia, M Shamsuzzoha; Uddin, M A; Joarder, Shefael K; Tariq, A_S B; Basak, A K (November 2025, Journal of Physics G: Nuclear and Particle Physics)

   Abstract A simple optical model (OPM) method using non-monotonic (NM) potentials characterized by a repulsive core from the microscopic theory of the Pauli-led energy-density functional (EDF) has been developed to investigate the¹⁶O+¹⁶O fusion at sub-Coulomb energies relevant to the oxygen burning. The study involves the analysis of the experimental fusion cross-section (FCS) data in energy range 6.92 ≤E_cm≤ 13.83 MeV, which includes the Coulomb barrier regionE_cm= 10.0–11.92 MeV. Apart from an excellent description of the existing FCS data in the studied energy range, the associated hindrance, characterized by theS-factor reaching a maximum and then gradually falling off at lower energies, so far suggested empirically for the system, is reproduced down to 4 MeV for the first time in the simple OPM. AnS-factor maximum ofS₀ = 3.15 × 10²⁵MeV.b atE₀ = 7.14 MeV is observed withT ≃ 2.6 GK, which conforms to the values reported for quiescent and explosive burning. Our reaction rate, deduced from the NM potential, compares well with the Caughlan and Fowler data. Dominant partial waves implicit in the observed maximumS-factor in the studied Gamow range are also explored. Our present findings, with the success of NM potentials, suggest thatthe nucleus–nucleus potential is non-monotonic. 

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3. Summer and nonsummer climatic signals in speleothem δ ¹⁸ O revealed by loess microcodium δ ¹⁸ O in East Asia

   https://doi.org/10.1073/pnas.2425565122  

   Zhang, Zeke; Liu, Zhengyu; Li, Gaojun; Cai, Yanjun; Wen, Qin; Cheng, Hai; Lawrence_Edwards, R; Lei, Jing; Liu, Heng; Jing, Zhaowei; et al (July 2025, Proceedings of the National Academy of Sciences)

   Speleothem δ18O records from central southern China have long been regarded as a key benchmark for Asian summer monsoon intensity. However, the similar δ18O minima observed among precession minima and their link to seasonal precipitation mixing remains unclear. Here, we present a 400,000-y record of summer precipitation δ18O from loess microcodium, which captures distinct precession cycles similar to those seen in speleothem δ18O records, particularly during glacial periods. Notably, our microcodium δ¹⁸O record reveals very low-δ¹⁸O values during precession minima at peak interglacials, a feature absent in speleothem δ¹⁸O records from central southern China. This discrepancy suggests that the mixed summer and nonsummer climatic signals substantially influence the speleothem δ¹⁸O records from central southern China. Proxy-model comparisons indicate that the lack of very low-δ¹⁸O values in speleothem δ¹⁸O records is due to an attenuated summer signal contribution, resulting from a lower summer-to-annual precipitation ratio in southern China at strong monsoon intervals. Our findings offer a potential explanation for the long-standing puzzle of the absence of 100- and 41-kyr cycles in speleothem δ¹⁸O records and underscore the critical role of seasonality in interpreting paleoclimatic proxies in central southern China. These insights also have broader implications for interpreting speleothem δ¹⁸O records globally, advocating for a more multiseason interpretive framework. 

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4. Variability and Controls on δ ¹⁸ O, d‐excess, and ∆′ ¹⁷ O in Southern Peruvian Precipitation

   https://doi.org/10.1029/2020JD034009  

   Aron, Phoebe G.; Poulsen, Christopher J.; Fiorella, Richard P.; Levin, Naomi E.; Acosta, Rene P.; Yanites, Brian J.; Cassel, Elizabeth J. (December 2021, Journal of Geophysical Research: Atmospheres)
5. Equatorial Undercurrent Influence on Surface Seawater δ ¹⁸ O Values in the Galápagos

   https://doi.org/10.1029/2022GL102074  

   Conroy, Jessica L.; Murray, Nicole K.; Patterson, Gillian S.; Schore, Aiden I.; Ikuru, Ima; Cole, Julia E.; Chillagana, David; Echeverria, Fernando (February 2023, Geophysical Research Letters)