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1. Measurement of the ratio of the scalar polarizability to the vector polarizability for the $6s{}^{2}S_{1/2}\to 7s{}^{2}S_{1/2}$ transition in cesium

   https://doi.org/10.1103/PhysRevA.109.062809  

   Quirk, Jonah A; Tanner, Carol E; Elliott, D S (June 2024, Physical Review A)

   We report measurements of the ratio of the scalar polarizability $$\alpha$$ to the vector polarizability $$\beta$$ for the $$6s ^2S_{1/2} \rightarrow 7s ^2S_{1/2}$$ transition in atomic cesium. These measurements are motivated by a discrepancy between the values of the vector transition polarizability as determined using two separate methods. In the present measurement, we use a two-pathway, coherent-control technique in which we observe the interference between a two-photon interaction driven by infrared light at 1079 nm and a linear Stark-induced interaction driven by the mutually-coherent second harmonic of this infrared beam at 540 nm. The result of our measurements is $$\alpha/\beta = -9.902 \: (9)$$, in good agreement with the previous determination of this ratio. This measurement, critical to the study of atomic parity violation in cesium, does not reduce the discrepancy between the two methods for the determination of the vector polarizability $$\beta$$ for this transition. 

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2. Measurement of the hyperfine coupling constants and absolute energies of the $12s {}^2{S}_{1/2}, 13s {}^2{S}_{1/2}$ , and $11d {}^2{D}_J$ levels in atomic cesium

   https://doi.org/10.1103/PhysRevA.105.022819  

   Quirk, Jonah A; Damitz, Amy; Tanner, Carol E; Elliott, D S (February 2022, Physical Review A)

   We report measurements of the absolute energies of the hyperfine components of the $$12s \ ^2S_{1/2}$$ and $$13s \ ^2S_{1/2}$$ levels of atomic cesium, $$^{133}$$Cs. Using the frequency difference between these components, we determine the hyperfine coupling constants for these states, and report these values with a relative uncertainty of $$\sim$$0.06\%. We also examine the hyperfine structure of the $$11d \ ^2D_{J}$$ ($J=3/2, 5/2$) states, and resolve the sign ambiguity of the hyperfine coupling constants from previous measurements of these states. We also derive new, high precision values for the state energies of the $$12s \ ^2S_{1/2}$$, $$13s \ ^2S_{1/2}$$ and $$11d \ ^2D_{J}$$ states of cesium. 

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3. Robust superconductivity and the suppression of charge-density wave in the quasi-skutterudites ${\text{Ca}}_3({\text{Ir}}_{1-x}{\text{Rh}}_x{)}_4{\text{Sn}}_{13}$ single crystals at ambient pressure

   https://doi.org/10.1088/1361-648X/ad5485  

   Krenkel, Elizabeth H; Tanatar, Makariy A; Ghimire, Sunil; Joshi, Kamal R; Chen, Shuzhang; Petrovic, Cedomir; Prozorov, Ruslan (June 2024, Journal of Physics: Condensed Matter)

   Abstract Single crystals of the quasi-skutterudite compounds Ca₃(Ir_1-xRh_x)₄Sn₁₃(3–4–13) were synthesized by flux growth and characterized by x-ray diffraction, energy dispersive x-ray spectroscopy, magnetization, resistivity, and radio frequency magnetic susceptibility techniques. The coexistence and competition between the charge density wave (CDW) and superconductivity was studied by varying the Rh/Ir ratio. The superconducting transition temperature, $T_{\mathrm{c}}$, varies from 7 K in pure Ir (x = 0) to 8.3 K in pure Rh (x = 1). Temperature-dependent electrical resistivity reveals monotonic suppression of the CDW transition temperature,T_CDW(x). The CDW starts in pure Ir,x = 0, atT_CDW≈ 40 K and extrapolates roughly linearly to zero at $x_c\approx$0.53–0.58 under the superconducting dome. Magnetization and transport measurements show a significant influence of CDW on superconducting and normal states. Meissner expulsion is substantially reduced in the CDW region, indicating competition between the CDW and superconductivity. The low-temperature resistivity is higher in the CDW part of the phase diagram, consistent with the reduced density of states due to CDW gapping. Its temperature dependence just above $T_{\mathrm{c}}$shows signs of non-Fermi liquid behavior in a cone-like composition pattern. We conclude that the Ca₃(Ir_1-xRh_x)₄Sn₁₃alloy is a good candidate for a composition-driven quantum critical point at ambient pressure. 

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4. Search for $h_b\left(2P\right)\to \gamma {\chi }_{bJ}\left(1P\right)$ at $\sqrt{s}=10.860\mathrm{GeV}$

   https://doi.org/10.1103/PhysRevD.111.L011102  

   Boschetti, A; Mussa, R; Tamponi, U; Adachi, I; Aihara, H; Asner, D M; Aushev, T; Ayad, R; Banerjee, Sw; Belous, K; et al (January 2025, Physical Review D)

   In the bottomonium sector, the hindered magnetic dipole transitions between P-wave states $h_b\left(2P\right)\to {\chi }_{bJ}\left(1P\right)\gamma$, $J=0$, 1, 2, are expected to be severely suppressed according to the relativized quark model, due to the spin flip of the $b$quark. Nevertheless, a recent model following the coupled-channel approach predicts the corresponding branching fractions to be enhanced by orders of magnitude. In this Letter, we report the first search for such transitions. We find no significant signals and set upper limits at 90% confidence level on the corresponding branching fractions: $\mathcal{B}\left[h_b\right(2P)\to \gamma {\chi }_{b0}(1P\left)\right]<2.7\times {10}^{-1}$, $\mathcal{B}\left[h_b\right(2P)\to \gamma {\chi }_{b1}(1P\left)\right]<5.4\times {10}^{-3}$and $\mathcal{B}\left[h_b\right(2P)\to \gamma {\chi }_{b2}(1P\left)\right]<1.3\times {10}^{-2}$. These values help to constrain the parameters of the coupled-channel models. The results are obtained using a $121.4{\mathrm{fb}}^{-1}$data sample taken around $\sqrt{s}=10.860\mathrm{GeV}$with the Belle detector at the KEKB asymmetric-energy $e^{+}{e}^{-}$collider. Published by the American Physical Society2025 

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5. Production of $\left(\text{anti-}\right){}^3\mathrm{He}$ and $\left(\text{anti-}\right){}^3\mathrm{H}$ in $p\text{-Pb}$ collisions at $\sqrt{s_{NN}}=5.02$ TeV

   https://doi.org/10.1103/PhysRevC.101.044906  

   Acharya, S.; Adamová, D.; Adler, A.; Adolfsson, J.; Aggarwal, M. M.; Aglieri Rinella, G.; Agnello, M.; Agrawal, N.; Ahammed, Z.; Ahmad, S.; et al (April 2020, Physical Review C)