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A d 33 value exceeding 350 pC N −1 , maintained up to 320 °C, and a large strain of 0.29% within 20% variation are achieved in a novel system of BKT–PT–PZ. The stable nanosized domains contribute to the temperature-insensitive high piezoelectricity.
Given the lack of fusion-relevant component test facilities, current estimates of the thermo-fluid performance of plasma-facing components are based for the most part on numerical simulations. A major source of uncertainty in these simulations is the semiempirical turbulence (closure) models for the Reynolds stresses appearing in the governing Reynolds-averaged Navier-Stokes equations, which involve a set of constants that depend upon the flow. The objective of this study is to evaluate Bayesian parameter estimation of turbulence closure constants in ANSYS Fluent to model heat transfer in impinging jets. The Bayesian statistical calibration produces a probability distribution for these constants from experimental data; the maximum a posteriori estimates are then taken to be the calibrated constants, or parameters. The turbulence model constants are calibrated using an experimental study of a submerged jet of air impinging on a flat heated surface at Reynolds numbers Re = O(10 4 ) and impingement distance in jet diameters H/d = 2. Numerical predictions using the calibrated model parameters are then compared with those generated using the default constants. Predictions obtained with model parameters calibrated on datasets of two different sizes are compared to evaluate the effect of the number of calibration samples. Lastly, the extrapolative ability of the calibrated model is examined by predictions at a Re beyond the calibration values.
The structural and electronic properties of KTaO 3 /KZnF 3 and KTaO 3 /KNiF 3 oxyfluoride superlattices are studied from first-principles density functional theory calculations. Here we highlight, that beyond a critical layer thickness, these systems exhibit an insulator to metal transition that gives rise to the appearance of two-dimensional electron and hole gas, confined both, due the band alignment, within the oxide layer. The origin of the insulator to metal transition is related to the polar discontinuity at the interfaces. The behavior is discussed in terms of a simple electrostatic model and compared to that of the prototypical LaAlO 3 /SrTiO 3 oxide system. The magnetic properties KTaO 3 /KNiF 3 superlattices are further discussed, revealing a sizable Rashba-type spin splitting at these interfaces, much larger than in similar oxide/oxide systems.
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We present the first publicly released catalog of sources obtained from the Hobby-Eberly Telescope Dark Energy Experiment (HETDEX). HETDEX is an integral field spectroscopic survey designed to measure the Hubble expansion parameter and angular diameter distance at 1.88 < z < 3.52 by using the spatial distribution of more than a million Lyα-emitting galaxies over a total target area of 540 deg 2 . The catalog comes from contiguous fiber spectra coverage of 25 deg 2 of sky from 2017 January through 2020 June, where object detection is performed through two complementary detection methods: one designed to search for line emission and the other a search for continuum emission. The HETDEX public release catalog is dominated by emission-line galaxies and includes 51,863 Ly$α$-emitting galaxy (LAE) identifications and 123,891 [O ii]-emitting galaxies at z < 0.5. Also included in the catalog are 37,916 stars, 5274 low-redshift (z < 0.5) galaxies without emission lines, and 4976 active galactic nuclei. The catalog provides sky coordinates, redshifts, line identifications, classification information, line fluxes, [O ii] and Ly$α$ line luminosities where applicable, and spectra for all identified sources processed by the HETDEX detection pipeline. Extensive testing demonstrates that HETDEX redshifts agree to within Δz < 0.02, 96.1% of the time to those in external spectroscopic catalogs. We measure the photometric counterpart fraction in deep ancillary Hyper Suprime-Cam imaging and find that only 55.5% of the LAE sample has an r-band continuum counterpart down to a limiting magnitude of r ~ 26.2 mag (AB) indicating that an LAE search of similar sensitivity to HETDEX with photometric preselection would miss nearly half of the HETDEX LAE catalog sample. Data access and details about the catalog can be found online at http://hetdex.org/. A copy of the catalogs presented in this work (Version 3.2) is available to download at Zenodo doi:10.5281/zenodo.7448504.
The GlueX experiment housed in Hall D of the Thomas Jefferson National Laboratory was created to map the light meson spectrum in order to contribute to the Standard Model of particle physics by strengthening our understanding of the strong interaction. GlueX is a medium-energy photoproduction experiment that utilizes a linearly polarized photon beam to create hadronic forms of matter.
Abstract Despite the observation of significant suppressions of $$b\rightarrow s\mu ^+\mu ^-$$ b → s μ + μ - branching ratios no clear sign of New Physics (NP) has been identified in $$\Delta F=2$$ Δ F = 2 observables $$\Delta M_{d,s}$$ Δ M d , s , $$\varepsilon _K$$ ε K and the mixing induced CP asymmetries $$S_{\psi K_S}$$ S ψ K S and $$S_{\psi \phi }$$ S ψ ϕ . Assuming negligible NP contributions to these observables allows to determine CKM parameters without being involved in the tensions between inclusive and exclusive determinations of $$|V_{cb}|$$ | V cb | and $$|V_{ub}|$$ | V ub | . Furthermore this method avoids the impact of NP on the determination of these parameters present likely in global fits. Simultaneously it provides SM predictions for numerous rare K and B branching ratios that are most accurate to date. Analyzing this scenario within $$Z^\prime $$ Z ′ models we point out, following the 2009 observations of Monika Blanke and ours of 2020, that despite the absence of NP contributions to $$\varepsilon _K$$ ε K , significant NP contributions to $$K^+\rightarrow \pi ^+\nu {\bar{\nu }}$$ K + → π + ν ν ¯ , $$K_{L}\rightarrow \pi ^0\nu {\bar{\nu }}$$ K L → π 0 ν ν ¯ , $$K_S\rightarrow \mu ^+\mu ^-$$ K S → μ + μ - , $$K_L\rightarrow \pi ^0\ell ^+\ell ^-$$ K L → π 0 ℓ + ℓ - , $$\varepsilon '/\varepsilon $$ ε ′ / ε and $$\Delta M_K$$ Δ M K can be present. In the simplest scenario, this is guaranteed, as far as flavour changes are concerned, by a single non-vanishing imaginary left-handed $$Z^\prime $$ Z ′ coupling $$g^L_{sd}$$ g sd L . This scenario implies very stringent correlations between the Kaon observables considered by us. In particular, the identification of NP in any of these observables implies automatically NP contributions to the remaining ones under the assumption of non-vanishing flavour conserving $$Z^\prime $$ Z ′ couplings to $$q{\bar{q}}$$ q q ¯ , $$\nu {\bar{\nu }}$$ ν ν ¯ , and $$\mu ^+\mu ^-$$ μ + μ - . A characteristic feature of this scenario is a strict correlation between $$K^+\rightarrow \pi ^+\nu {\bar{\nu }}$$ K + → π + ν ν ¯ and $$K_{L}\rightarrow \pi ^0\nu {\bar{\nu }}$$ K L → π 0 ν ν ¯ branching ratios on a branch parallel to the Grossman-Nir bound. Moreover, $$\Delta M_K$$ Δ M K is automatically suppressed as seems to be required by the results of the RBC-UKQCD lattice QCD collaboration. Furthermore, there is no NP contribution to $$K_L\rightarrow \mu ^+\mu ^-$$ K L → μ + μ - which otherwise would bound NP effects in $$K^+\rightarrow \pi ^+\nu {\bar{\nu }}$$ K + → π + ν ν ¯ . Of particular interest are the correlations of $$K^+\rightarrow \pi ^+\nu {\bar{\nu }}$$ K + → π + ν ν ¯ and $$K_{L}\rightarrow \pi ^0\nu {\bar{\nu }}$$ K L → π 0 ν ν ¯ branching ratios and of $$\Delta M_K$$ Δ M K with the ratio $$\varepsilon '/\varepsilon $$ ε ′ / ε . We investigate the impact of renormalization group effects in the context of the SMEFT on this simple scenario.
We present the results of the first Dalitz plot analysis of the decay D 0 → K – π + η . The analysis is performed on a data set corresponding to an integrated luminosity of 953 fb – 1 collected by the Belle detector at the asymmetric-energy e + e – KEKB collider. The Dalitz plot is well described by a combination of the six resonant decay channels K ¯ * ( 892 ) 0 η , K – a 0 ( 980 ) + , K – a 2 ( 1320 ) + , K ¯ * ( 1410 ) 0 η , K * ( 1680 ) – π + and K 2 * ( 1980 ) – π + , together with K π and K η S-wave components. The decays K * ( 1680 ) – → K – η and K 2 * ( 1980 ) – → K – η are observed for the first time. We measure ratio of the branching fractions, B ( D 0 → K – π + η ) B ( D 0 → K – π + ) = 0.500 ± 0.002 ( stat ) ± 0.020 ( syst ) ± 0.003 ( B PDG ) . Using the Dalitz fit result, the ratio B ( K * ( 1680 ) → K η ) B ( K * ( 1680 ) → K π ) is measured to be 0.11 ± 0.02 ( stat ) – 0.04 + 0.06 ( syst ) ± 0.04 ( B PDG ) ; this is much lower than the theoretical expectations ( ≈ 1 ) made under the assumption that K * ( 1680 ) is a pure 1 3 D 1 state. The product branching fraction B ( D 0 → [ K 2 * ( 1980 ) – → K – η ] π + ) = ( 2. 2 – 1.9 + 1.7 ) × 10 – 4 is determined. In addition, the π η ' contribution to the a 0 ( 980 ) ± resonance shape is confirmed with 10.1 σ statistical significance using the three-channel Flatté model. We also measure B ( D 0 → K ¯ * ( 892 ) 0 η ) = ( 1.4 1 – 0.12 + 0.13 ) % . This is consistent with, and more precise than, the current world average ( 1.02 ± 0.30 ) % , deviates with a significance of more than 3 σ from the theoretical predictions of (0.51–0.92)%.
K is alpha Samarium structured and crystallizes in the trigonal R-3m space group. The structure is three-dimensional. there are five inequivalent K sites. In the first K site, K is bonded to twelve K atoms to form a mixture of distorted face, edge, and corner-sharing KK12 cuboctahedra. There are six shorter (4.63 Å) and six longer (4.79 Å) K–K bond lengths. In the second K site, K is bonded to twelve K atoms to form a mixture of distorted face, edge, and corner-sharing KK12 cuboctahedra. There are three shorter (4.64 Å) and six longer (4.79 Å) K–K bond lengths. In the third K site, K is bonded to twelve K atoms to form a mixture of distorted face, edge, and corner-sharing KK12 cuboctahedra. There are six shorter (4.63 Å) and six longer (4.79 Å) K–K bond lengths. In the fourth K site, K is bonded to twelve K atoms to form a mixture of distorted face, edge, and corner-sharing KK12 cuboctahedra. There are three shorter (4.64 Å) and six longer (4.79 Å) K–K bond lengths. In the fifth K site, K is bonded to sixteen K atoms to form a mixture of distorted face, edge, and corner-sharing KK16 cuboctahedra. There are a spread of K–K bond distances ranging from 4.79–9.58 Å.
K(O3I)2 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are two inequivalent K sites. In the first K site, K is bonded in a 8-coordinate geometry to eight O atoms. There are a spread of K–O bond distances ranging from 2.75–2.91 Å. In the second K site, K is bonded in a 8-coordinate geometry to eight O atoms. There are a spread of K–O bond distances ranging from 2.66–3.05 Å. There are twelve inequivalent O sites. In the first O site, O is bonded in a 3-coordinate geometry to two equivalent K and one I atom. The O–I bond length is 1.83 Å. In the second O site, O is bonded in a distorted bent 150 degrees geometry to one K and one I atom. The O–I bond length is 1.78 Å. In the third O site, O is bonded in a 1-coordinate geometry to two K and one I atom. The O–I bond length is 1.82 Å. In the fourth O site, O is bonded in a distorted trigonal planar geometry to one K and two I atoms. There are one shorter (1.97 Å) and one longer (2.14 Å) O–I bond lengths. In the fifth O site, O is bonded in a distorted trigonal non-coplanar geometry to one K and two I atoms. There are one shorter (1.91 Å) and one longer (2.27 Å) O–I bond lengths. In the sixth O site, O is bonded in a 1-coordinate geometry to two equivalent K and two I atoms. There are one shorter (1.82 Å) and one longer (2.75 Å) O–I bond lengths. In the seventh O site, O is bonded in a distorted trigonal non-coplanar geometry to two K and one I atom. The O–I bond length is 1.83 Å. In the eighth O site, O is bonded in a distorted bent 120 degrees geometry to one K and one I atom. The O–I bond length is 1.82 Å. In the ninth O site, O is bonded in a bent 150 degrees geometry to one K and one I atom. The O–I bond length is 1.78 Å. In the tenth O site, O is bonded in a distorted trigonal planar geometry to one K and two I atoms. There are one shorter (1.88 Å) and one longer (2.28 Å) O–I bond lengths. In the eleventh O site, O is bonded in a 1-coordinate geometry to one K and two I atoms. There are one shorter (1.87 Å) and one longer (2.37 Å) O–I bond lengths. In the twelfth O site, O is bonded in a 3-coordinate geometry to one K and two I atoms. There are one shorter (1.81 Å) and one longer (2.60 Å) O–I bond lengths. There are four inequivalent I sites. In the first I site, I is bonded in a distorted trigonal non-coplanar geometry to three O atoms. In the second I site, I is bonded in a distorted trigonal non-coplanar geometry to three O atoms. In the third I site, I is bonded in a distorted octahedral geometry to six O atoms. In the fourth I site, I is bonded in a 6-coordinate geometry to six O atoms.
K is alpha structured and crystallizes in the cubic I-43m space group. The structure is three-dimensional and consists of two potassium molecules and one K framework. In the K framework, there are three inequivalent K sites. In the first K site, K is bonded in a trigonal non-coplanar geometry to three equivalent K atoms. All K–K bond lengths are 4.59 Å. In the second K site, K is bonded in a 6-coordinate geometry to eight K atoms. There are a spread of K–K bond distances ranging from 4.23–4.80 Å. In the third K site, K is bonded in a 8-coordinate geometry to eight K atoms. Both K–K bond lengths are 4.76 Å.
Small-conductance (K Ca 2.2) and intermediate-conductance (K Ca 3.1) Ca 2+ -activated K + channels are gated by a Ca 2+ -calmodulin dependent mechanism. NS309 potentiates the activity of both K Ca 2.2 and K Ca 3.1, while rimtuzalcap selectively activates K Ca 2.2. Rimtuzalcap has been used in clinical trials for the treatment of spinocerebellar ataxia and essential tremor. We report cryo-electron microscopy structures of NS309-bound K Ca 2.2 and K Ca 3.1, in addition to structures of rimtuzalcap-bound K Ca 2.2 and mutant K Ca 3.1_R355K. The different conformations of calmodulin and the cytoplasmic HC helices in the two channels underlie the subtype-selectivity of rimtuzalcap for K Ca 2.2. NS309 binds to pre-existing pockets in both channels, while the bulkier rimtuzalcap binds in an induced-fit pocket in K Ca 2.2 requiring conformational changes. In K Ca 2.2, calmodulin’s N-lobes are sufficiently far apart to enable conformational changes to accommodate either NS309 or rimtuzalcap. In K Ca 3.1, calmodulin’s N-lobes are closer to each other and constrained by K Ca 3.1’s HC helices, which allows binding of NS309 but not rimtuzalcap. Replacement of arginine-355 in K Ca 3.1’s HB helix with lysine (K Ca 3.1_R355K) allows the binding of rimtuzalcap and renders the mutant channel sensitive to rimtuzalcap. These structures provide a framework for structure-based drug design targeting K Ca 2.2 channels.
K2(BH)9BH crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional and consists of four boranediylradical molecules and one K2(BH)9 framework. In the K2(BH)9 framework, there are two inequivalent K sites. In the first K site, K is bonded in a 8-coordinate geometry to eight H atoms. There are a spread of K–H bond distances ranging from 2.67–3.05 Å. In the second K site, K is bonded in a 8-coordinate geometry to eight H atoms. There are a spread of K–H bond distances ranging from 2.79–3.07 Å. There are nine inequivalent B sites. In the first B site, B is bonded in a distorted single-bond geometry to one H atom. The B–H bond length is 1.21 Å. In the second B site, B is bonded in a distorted single-bond geometry to one H atom. The B–H bond length is 1.21 Å. In the third B site, B is bonded in a distorted single-bond geometry to one H atom. The B–H bond length is 1.21 Å. In the fourth B site, B is bonded in a distorted single-bond geometry to one H atom. The B–H bond length is 1.21 Å. In the fifth B site, B is bonded in a distorted single-bond geometry to one H atom. The B–H bond length is 1.20 Å. In the sixth B site, B is bonded in a distorted single-bond geometry to one H atom. The B–H bond length is 1.20 Å. In the seventh B site, B is bonded in a distorted single-bond geometry to one H atom. The B–H bond length is 1.21 Å. In the eighth B site, B is bonded in a distorted single-bond geometry to one H atom. The B–H bond length is 1.21 Å. In the ninth B site, B is bonded in a distorted single-bond geometry to one H atom. The B–H bond length is 1.21 Å. There are nine inequivalent H sites. In the first H site, H is bonded in a distorted bent 120 degrees geometry to one K and one B atom. In the second H site, H is bonded in a single-bond geometry to two K and one B atom. In the third H site, H is bonded in a distorted single-bond geometry to two equivalent K and one B atom. In the fourth H site, H is bonded in a distorted single-bond geometry to two K and one B atom. In the fifth H site, H is bonded in a single-bond geometry to two equivalent K and one B atom. In the sixth H site, H is bonded in a distorted single-bond geometry to two equivalent K and one B atom. In the seventh H site, H is bonded in a distorted single-bond geometry to two K and one B atom. In the eighth H site, H is bonded in a distorted single-bond geometry to one K and one B atom. In the ninth H site, H is bonded in a single-bond geometry to two K and one B atom.