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1. Impact of the New 65 As(p,γ) 66 Se Reaction Rate on the Two-proton Sequential Capture of 64 Ge, Weak GeAs Cycles, and Type I X-Ray Bursts Such as the Clocked Burster GS 1826−24

   https://doi.org/10.3847/1538-4357/ac4d8b  

   Lam, Yi Hua ; Liu, Zi Xin ; Heger, Alexander ; Lu, Ning ; Jacobs, Adam Michael ; Johnston, Zac ( April 2022 , The Astrophysical Journal)

   Abstract We reassess the 65 As(p, γ ) 66 Se reaction rates based on a set of proton thresholds of 66 Se, S p ( 66 Se), estimated from the experimental mirror nuclear masses, theoretical mirror displacement energies, and full p f -model space shell-model calculation. The self-consistent relativistic Hartree–Bogoliubov theory is employed to obtain the mirror displacement energies with much reduced uncertainty, and thus reducing the proton-threshold uncertainty up to 161 keV compared to the AME2020 evaluation. Using the simulation instantiated by the one-dimensional multi-zone hydrodynamic code, K epler , which closely reproduces the observed GS 1826−24 clocked bursts, the present forward and reverse 65 As(p, γ ) 66 Se reaction rates based on a selected S p ( 66 Se) = 2.469 ± 0.054 MeV, and the latest 22 Mg( α ,p) 25 Al, 56 Ni(p, γ ) 57 Cu, 57 Cu(p, γ ) 58 Zn, 55 Ni(p, γ ) 56 Cu, and 64 Ge(p, γ ) 65 As reaction rates, we find that though the GeAs cycles are weakly established in the rapid-proton capture process path, the 65 As(p, γ ) 66 Se reaction still strongly characterizes the burst tail end due to the two-proton sequential capture on 64 Ge, not found by the Cyburt et al. sensitivity study. The 65 As(p, γ ) 66 Se reaction influences the abundances of nuclei A = 64, 68, 72, 76, and 80 up to a factor of 1.4. The new S p ( 66 Se) and the inclusion of the updated 22 Mg( α ,p) 25 Al reaction rate increases the production of 12 C up to a factor of 4.5, which is not observable and could be the main fuel for a superburst. The enhancement of the 12 C mass fraction alleviates the discrepancy in explaining the origin of the superburst. The waiting point status of and two-proton sequential capture on 64 Ge, the weak-cycle feature of GeAs at a region heavier than 64 Ge, and the impact of other possible S p ( 66 Se) are also discussed. 

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2. The Missing Link: Au 191 (SPh- t Bu) 66 Janus Nanoparticle with Molecular and Bulk-Metal-like Properties

   https://doi.org/10.1021/jacs.0c05685  

   Sakthivel, Naga Arjun ; Shabaninezhad, Masoud ; Sementa, Luca ; Yoon, Bokwon ; Stener, Mauro ; Whetten, Robert L. ; Ramakrishna, Guda ; Fortunelli, Alessandro ; Landman, Uzi ; Dass, Amala ( September 2020 , Journal of the American Chemical Society)

   null (Ed.)
3. Spectroscopic study of the 4 f 7 6 s 2 8 S 7/2∘−4 f 7 ( 8 S ∘ )6 s 6 p ( 1 P ∘ ) 8 P 9/2 transition in neutral europium-151 and europium-153: absolute frequency and hyperfine structure

   https://doi.org/10.1364/JOSAB.467968  

   Herd, M. T. ; Maruko, C. ; Herzog, M. M. ; Brand, A. ; Cannon, G. ; Duah, B. ; Hollin, N. ; Karani, T. ; Wallace, A. ; Whitmore, M. ; et al ( September 2022 , Journal of the Optical Society of America B)

   We report on spectroscopic measurements on the$4f^{7}6s^2{}^8{S}_{7/2}^{\circ <\#comment/>}\to <\#comment/>4f^7{(}^8{S}^{\circ <\#comment/>})6s6p{(}^1{P}^{\circ <\#comment/>}){}^8{P}_{9/2}$transition in neutral europium-151 and europium-153 at 459.4 nm. The center of gravity frequencies for the 151 and 153 isotopes, reported for the first time in this paper, to our knowledge, were found to be 652,389,757.16(34) MHz and 652,386,593.2(5) MHz, respectively. The hyperfine coefficients for the$6s6p{(}^1{P}^{\circ <\#comment/>}){}^8{P}_{9/2}$state were found to be$\mathrm{A}(151)=-<\#comment/>228.84(2)\mathrm{M}\mathrm{H}\mathrm{z}$,$\mathrm{B}(151)=226.9(5)\mathrm{M}\mathrm{H}\mathrm{z}$and$\mathrm{A}(153)=-<\#comment/>101.87(6)\mathrm{M}\mathrm{H}\mathrm{z}$,$\mathrm{B}(153)=575.4(1.5)\mathrm{M}\mathrm{H}\mathrm{z}$, which all agree with previously published results except for A(153), which shows a small discrepancy. The isotope shift is found to be 3163.8(6) MHz, which also has a discrepancy with previously published results.

    

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4. Quantum-vibrational-state-selected Integral Cross Sections and Product Branching Ratios for the Ion-molecule Reactions of N 2 + ( X 2 Σ g + ; v + = 0–2) + H 2 O and H 2 O + ( X 2 B 1 : v 1 + v 2 + v 3 + = 000 and 100) + N 2 in the Collision Energy Range of 0.04–10.00 eV

   https://doi.org/10.3847/1538-4357/aac9bf  

   Xu, Yuntao ; Xiong, Bo ; Chang, Yih Chung ; Ng, Cheuk-Yiu ( July 2018 , The Astrophysical Journal)
5. Layered and Cubic Semiconductors A Ga M ′ Q 4 ( A + = K + , Rb + , Cs + , Tl + ; M ′ 4+ = Ge 4+ , Sn 4+ ; Q 2– = S 2– , Se 2– ) and High Third-Harmonic Generation

   https://doi.org/10.1021/jacs.0c08638  

   Friedrich, Daniel ; Byun, Hye Ryung ; Hao, Shiqiang ; Patel, Shane ; Wolverton, Chris ; Jang, Joon Ik ; Kanatzidis, Mercouri G. ( October 2020 , Journal of the American Chemical Society)

   null (Ed.)