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1. Asymptotic normalization coefficients for $\alpha +{}^{12}\mathrm{C}$ synthesis and the $S$ factor for ${}^{12}\mathrm{C}(\alpha ,\gamma ){}^{16}\mathrm{O}$ radiative capture

   https://doi.org/10.1103/PhysRevC.110.055803  

   Mukhamedzhanov, A M; deBoer, R J; Irgaziev, B F; Blokhintsev, L D; Kadyrov, A S; Savin, D A (November 2024, Physical Review C)

   : The ${}^{12}\mathrm{C}(\alpha ,\gamma ){}^{16}\mathrm{O}$ reaction, determining the survival of carbon in red giants, is of interest for nuclear reaction theory and nuclear astrophysics. A specific feature of the ${}^{16}\mathrm{O}$ nuclear structure is the presence of two subthreshold bound states, (6.92 MeV, $2^{+}$ ) and (7.12 MeV, $1^{-}$ ), that dominate the behavior of the low-energy $S$ factor. The strength of these subthreshold states is determined by their asymptotic normalization coefficients (ANCs), which need to be known with high accuracy. : The objective of this research is to examine how the subthreshold and ground-state ANCs impact the low-energy $S$ factor, especially at the key astrophysical energy of $300\mathrm{keV}$ . The $S$ factors are calculated within the framework of the $R$ -matrix method using the code. Our total $S$ factor takes into account the $E1$ and $E2$ transitions to the ground state of ${}^{16}\mathrm{O}$ including the interference of the subthreshold and higher resonances, which also interfere with the corresponding direct captures, and cascade radiative captures to the ground state of ${}^{16}\mathrm{O}$ through four subthreshold states: $0_2^{+},3^{-},2^{+}$ , and $1^{-}$ . To evaluate the impact of subthreshold ANCs on the low-energy $S$ factor, we employ two sets of the ANCs. The first selection, which offers higher ANC values, is attained through the extrapolation process [Blokhintsev , ]. The set with low ANC values was employed by deBoer []. A detailed comparison of the $S$ factors at the most effective astrophysical energy of 300 keV is provided, along with an investigation into how the ground-state ANC affects this $S$ factor. : The contribution to the total $E1$ and $E2S$ factors from the corresponding subthreshold resonances at $300\mathrm{keV}$ are $(71–74)\%$ and $(102–103)\%$ , respectively. The correlation of the uncertainties of the subthreshold ANCs with the $E1$ and $E2S\left(300\mathrm{keV}\right)$ factors is found. The $E1$ transition of the subthreshold resonance $1^{-}$ does not depend on the ground-state ANC but interferes constructively with a broad $(9.585\mathrm{MeV};1^{-})$ resonance giving (for the present subthreshold ANC) an additional $26\%$ contribution to the total $E1S\left(300\mathrm{keV}\right)$ factor. Interference of the $E2$ transition through the subthreshold resonance $2^{+}$ with direct capture is almost negligible for small ground-state ANC of $58{\mathrm{fm}}^{-1/2}$ . However, its interference with direct capture for higher ground-state ANC of $337{\mathrm{fm}}^{-1/2}$ is significant and destructive, contributing $-27\%$ . The low-energy $S_{E2}\left(300\mathrm{keV}\right)$ factor experiences a smaller increase when both subthfreshold and the ground-state ANCs rise together due to their anticorrelation, compared to when only the subthreshold ANCs increase. Published by the American Physical Society2024 

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2. Effect of an applied magnetic field on ${}^{84}\mathrm{Sr} n^1{D}_2$ ultralong-range Rydberg dimers

   https://doi.org/10.1103/6bj1-1ywm  

   Yoshida, S; Wang, C; Li, A; Kanungo, S K; Killian, T C; Dunning, F B (August 2026, Physical Review A)

   Photoassociation of $5snd {}^1{D}_2-5s^2 {}^1{S}_0$ ultralong-range Rydberg dimers from an ultracold ${}^{84}\mathrm{Sr}$ atomic gas in a magnetic field is studied. In the absence of magnetic fields, the electronic wave function is aligned along the rotating molecular axis through electron-atom scattering. With increasing magnetic field strength, the symmetry axis of the electron wave function becomes determined by the applied field. While the ground-state atom has no spin or net charge to interact directly with the magnetic field, the dimer wave function in the limit of strong magnetic field becomes aligned along the applied field. Photoassociation spectra show that with increasing field, an increasing number of rovibrational states are excited, indicating strong coupling between rotational states within the Rydberg dimer. 

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3. Measurement of Angular Coefficients of $\overline{B}\to D^{*}\ell {\overline{\nu }}_{\ell }$ : Implications for $\left|V_{cb}\right|$ and Tests of Lepton Flavor Universality

   https://doi.org/10.1103/PhysRevLett.133.131801  

   Prim, M T; Bernlochner, F; Metzner, F; Aihara, H; Asner, D M; Aushev, T; Ayad, R; Babu, V; Banerjee, Sw; Behera, P; et al (September 2024, Physical Review Letters)

   We measure the complete set of angular coefficients $J_i$ for exclusive $\overline{B}\to D^{*}\ell {\overline{\nu }}_{\ell }$ decays ( $\ell =e$ , $\mu$ ). Our analysis uses the full $711{\mathrm{fb}}^{-1}$ Belle dataset with hadronic tag-side reconstruction. The results allow us to extract the form factors describing the $\overline{B}\to D^{*}$ transition and the Cabibbo-Kobayashi-Maskawa matrix element $\left|V_{\mathrm{cb}}\right|$ . Using recent lattice QCD calculations for the hadronic form factors, we find $\left|V_{\mathrm{cb}}\right|=(40.7\pm 0.7)\times {10}^{-3}$ using the Boyd-Grinstein-Lebed parametrization, compatible with determinations from inclusive semileptonic decays. We search for lepton flavor universality violation as a function of the hadronic recoil parameter $w$ and investigate the differences of the electron and muon angular distributions. We find no deviation from standard model expectations. Published by the American Physical Society2024 

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4. Precision measurement of lifetime and branching ratios of the $4f^{13}5d6s^1{[5/2]}_{5/2}$ state in ${\mathrm{Yb}}^{+}$ ions

   https://doi.org/10.1103/mwwc-kng1  

   Duraisamy_Suganthi, Midhuna; So, Visal; Menon, Abhishek; Tomaras, George; Zhuravel, Roman; Pagano, Guido (December 2025, Physical Review Research)

   We report spectroscopic and time-resolved experimental observations to characterize the $\left[\mathrm{Xe}\right]4f^{13}\left({}^{2}F_{5/2}^o\right)5d6s\left({}^{1}D\right){}^1{[5/2]}_{5/2}^o$ state in ${}^{172}\mathrm{Yb}^{+}$  ions. We access this state from the metastable $4f^{14}5d\left({}^{2}D_{3/2,5/2}\right)$ manifold and observe an unexpectedly long lifetime of $\tau =37.9\left(9\right)\mu \mathrm{s}$  that allows visible Rabi oscillations and resolved-sideband spectroscopy. Using a combination of coherent population dynamics, high-fidelity detection and heralded state preparation, and optical pumping methods, we measure the branching ratios to the ${}^{2}D_{3/2}, {}^{2}D_{5/2}$ , and ${}^{2}S_{1/2}$ states to be $0.359\left(2\right)$ , 0.639(2), and $0.0023\left(16\right)$ , respectively. The branching ratio to the $4f^{13}6s^2\left({{}^{2}F}_{7/2}\right)$ is compatible with zero within our experimental resolution. We also report measurements of Landé $g$ -factor of the ${}^1{[5/2]}_{5/2}^o$ state. Further, the branching ratio of the ${}^{2}D_{5/2}$ to ${}^{2}S_{1/2}$ decay in ${}^{172}\mathrm{Yb}^{+}$  was measured to be 0.188(3), improving its relative uncertainty by an order of magnitude. Our measurements provide experimental benchmarks for better understanding the atomic structure of ${\mathrm{Yb}}^{+}$  ions, which still lacks accurate numerical descriptions, and the use of high-lying excited states for partial detection and qubit manipulation in the architecture. 

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5. Strength measurements of the $E_{\mathrm{R}}^{\mathrm{lab}}=647$ and 1842 keV resonances in the ${}^{40}\mathrm{Ca}(p,\gamma ){}^{41}\mathrm{Sc}$ reaction and their relevance in novae nucleosynthesis

   https://doi.org/10.1103/PhysRevC.111.025804  

   Sidhu, R S; deBoer, R J; Görres, J; Wiescher, M; Koros, J; Manukyan, K; Matney, M; McDonaugh, J; Picciotto, V; Sanchez, A T; et al (February 2025, Physical Review C)

   Here we report on the direct measurement of the resonance strengths of the $E_{\mathrm{R}}^{\mathrm{lab}}=647\mathrm{keV}$ and 1842 keV resonances in the ${}^{40}\mathrm{Ca}(p,\gamma ){}^{41}\mathrm{Sc}$ reaction. At novae temperatures, $0.2<T_9<0.7$ , the ${}^{40}\mathrm{Ca}(p,\gamma ){}^{41}\mathrm{Sc}$ reaction is governed by the low energy resonance at $E_{\mathrm{R}}^{\mathrm{lab}}=647\mathrm{keV}$ , whereas the $E_{\mathrm{R}}^{\mathrm{lab}}=1842\mathrm{keV}$ resonance serves as a normalization standard for nuclear reaction experiments within the astrophysically relevant energy range. For the $E_{\mathrm{R}}^{\mathrm{lab}}=647\mathrm{keV}$ resonance, we obtain a resonance strength $\omega \gamma =(2.51\pm 0.{09}_{\mathrm{stat}}\pm 0.{22}_{\mathrm{syst}})\mathrm{meV}$ , with an uncertainty a factor of 2.5 smaller than the previous direct measurement value. For the $E_{\mathrm{R}}^{\mathrm{lab}}=1842\mathrm{keV}$ resonance, we obtain a resonance strength $\omega \gamma =(0.148\pm 0.{006}_{\mathrm{stat}}\pm 0.{013}_{\mathrm{syst}})\mathrm{eV}$ , which is consistent with previous studies but deviates by $2\sigma$ from the most recent measurement. Our results suggest ${}^{40}\mathrm{Ca}$ to be a strong waiting point in the nucleosynthesis path of oxygen-neon (ONe) novae. Published by the American Physical Society2025 

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