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1. Study of the ⁴⁴ Ti(α, p) ⁴⁷ V reaction rate using high-precision ⁵⁰ Cr(p, t) ⁴⁸ Cr measurements

   https://doi.org/10.1088/1742-6596/2586/1/012106  

   Binda, S D; Adsley, P; Long, A M; Berg, G; Brümmer, J W; Couder, M; Görres, J; Kamimota, M; Khumalo, N; Köhne, M; et al (September 2023, Journal of Physics: Conference Series)

   Abstract The abundance and distribution of⁴⁴Ti tells us about the nature of the core-collapse supernovae explosions. There is a need to understand the nuclear reaction network creating and destroying⁴⁴Ti in order to use it as a probe for the explosive mechanism. The⁴⁴Ti(α, p)⁴⁷V reaction is a very important reaction and it controls the destruction of⁴⁴Ti. Difficulties with direct measurements have led to an attempt to study this reaction indirectly. Here, the first step of the indirect study which is the identification of levels of the compound nucleus⁴⁸Cr is presented. A 100-MeV proton beam was incident on a⁵⁰Cr target. States in⁴⁸Cr were populated in the⁵⁰Cr(p, t)⁴⁸Cr reaction. The tritons were momentum-analysed in the K600 Q2D magnetic spectrometer at iThemba LABS. 

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2. Thermonuclear ²⁸ P(p, γ ) ²⁹ S reaction rate and astrophysical implication in ONe nova explosion

   https://doi.org/10.1051/0004-6361/202449536  

   Liu, J B; José, J; Hou, S Q; Pignatari, M; Trueman, T_C L; Longland, R; Li, J G; Bertulani, C A; Xu, X X (July 2024, Astronomy & Astrophysics)

   Context.An accurate²⁸P(p,γ)²⁹S reaction rate is crucial to defining the nucleosynthesis products of explosive hydrogen burning in ONe novae. Using the recently released nuclear mass of²⁹S, together with a shell model and a direct capture calculation, we reanalyzed the²⁸P(p,γ)²⁹S thermonuclear reaction rate and its astrophysical implication. Aims.We focus on improving the astrophysical rate for²⁸P(p,γ)²⁹S based on the newest nuclear mass data. Our goal is to explore the impact of the new rate and associated uncertainties on the nova nucleosynthesis. Methods.We evaluated this reaction rate via the sum of the isolated resonance contribution instead of the previously used Hauser-Feshbach statistical model. The corresponding rate uncertainty at different energies was derived using a Monte Carlo method. Nova nucleosynthesis is computed with the 1D hydrodynamic code SHIVA. Results.The contribution from the capture on the first excited state at 105.64 keV in²⁸P is taken into account for the first time. We find that the capture rate on the first excited state in²⁸P is up to more than 12 times larger than the ground-state capture rate in the temperature region of 2.5 × 10⁷K to 4 × 10⁸K, resulting in the total²⁸P(p,γ)²⁹S reaction rate being enhanced by a factor of up to 1.4 at ~1 × 10⁹K. In addition, the rate uncertainty has been quantified for the first time. It is found that the new rate is smaller than the previous statistical model rates, but it still agrees with them within uncertainties for nova temperatures. The statistical model appears to be roughly valid for the rate estimation of this reaction in the nova nucleosynthesis scenario. Using the 1D hydrodynamic code SHIVA, we performed the nucleosynthesis calculations in a nova explosion to investigate the impact of the new rates of²⁸P(p,γ)²⁹S. Our calculations show that the nova abundance pattern is only marginally affected if we use our new rates with respect to the same simulations but statistical model rates. Finally, the isotopes whose abundance is most influenced by the present²⁸P(p,γ)²⁹S uncertainty are²⁸Si,^33,34S,^35,37Cl, and³⁶Ar, with relative abundance changes at the level of only 3% to 4%. 

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3. New ²⁶ P(p, γ) ²⁷ S Thermonuclear Reaction Rate and Its Astrophysical Implications in the rp-process

   https://doi.org/10.3847/1538-4357/accf9c  

   Hou, S. Q.; Liu, J. B.; Trueman, T. C. L.; Li, J. G.; Pignatari, M.; Bertulani, C. A.; Xu, X. X. (June 2023, The Astrophysical Journal)

   Abstract Accurate nuclear reaction rates for²⁶P(p,γ)²⁷S are pivotal for a comprehensive understanding of therp-process nucleosynthesis path in the region of proton-rich sulfur and phosphorus isotopes. However, large uncertainties still exist in the current rate of²⁶P(p,γ)²⁷S because of the lack of nuclear mass and energy level structure information for²⁷S. We reevaluate this reaction rate using the experimentally constrained²⁷S mass, together with the shell model predicted level structure. It is found that the²⁶P(p,γ)²⁷S reaction rate is dominated by a direct capture reaction mechanism despite the presence of three resonances atE= 1.104, 1.597, and 1.777 MeV above the proton threshold in²⁷S. The new rate is overall smaller than the other previous rates from the Hauser–Feshbach statistical model by at least 1 order of magnitude in the temperature range of X-ray burst interest. In addition, we consistently update the photodisintegration rate using the new²⁷S mass. The influence of new rates of forward and reverse reaction in the abundances of isotopes produced in therp-process is explored by postprocessing nucleosynthesis calculations. The final abundance ratio of²⁷S/²⁶P obtained using the new rates is only 10% of that from the old rate. The abundance flow calculations show that the reaction path²⁶P(p,γ)²⁷S(β⁺,ν)²⁷P is not as important as previously thought for producing²⁷P. The adoption of the new reaction rates for²⁶P(p,γ)²⁷S only reduces the final production of aluminum by 7.1% and has no discernible impact on the yield of other elements. 

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4. Visible Light Promotes P ^III /P ^V -Catalyzed Reductive N -Arylation of Nitroarenes at Room Temperature

   https://doi.org/10.1021/acscatal.5c04341  

   Kang, Bora; Lavagnino, Marissa N; Gordon, Jesse B; Reynolds, Kristopher G; Nocera, Daniel G; Radosevich, Alexander T (July 2025, ACS Catalysis)
5. Comparison of Low‐Density Lipoprotein Oxidation by Hydrophilic O( ³ P)‐Precursors and Lipid‐O( ³ P)‐Precursor Conjugates

   https://doi.org/10.1111/php.13803  

   Maness, Peter F.; Cone, Grant W.; Ford, David A.; McCulla, Ryan D. (March 2023, Photochemistry and Photobiology)

   Abstract Lipid oxidation by reactive oxygen species (ROS) provide several different oxidation products that have been implicated in inflammatory responses. Ground state atomic oxygen [O(³P)] is produced by the photodeoxygenation of certain heterocyclic oxides and has a reactivity that is unique from other ROS. Due to the reactive nature of O(³P), the site of O(³P)‐generation is expected to influence the products in heterogenous solutions or environments. In this work, the oxidation of low‐density lipoprotein (LDL) by lipids with covalently bound O(³P)‐photoprecursors was compared to more hydrophilic O(³P)‐photoprecursors. Lipid oxidation products were quantified after Bligh‐Dyer extraction and pentafluorobenzyl bromide (PFB) derivatization by GC–MS. Unlike the more hydrophilic O(³P)‐photoprecursors, the oxidation of LDL during the irradiation of lipid‐(O³P)‐photoprecursor conjugates showed little quenching by the addition of the O(³P)‐scavenging sodium allyl sulfonate. This indicated that lipophilic O(³P)‐photoprecursors are expected to generate lipid oxidation products where other more hydrophilic O(³P)‐photoprecursors could be quenched by other reactive groups present in solution or the environment. 

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