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K(MoS)3 crystallizes in the hexagonal P6_3/m space group. The structure is three-dimensional. K is bonded in a trigonal planar geometry to three equivalent S atoms. All K–S bond lengths are 3.11 Å. Mo is bonded in a distorted see-saw-like geometry to four equivalent S atoms. There are a spread of Mo–S bond distances ranging from 2.49–2.60 Å. S is bonded in a 5-coordinate geometry to one K and four equivalent Mo atoms.
K(IrP)2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. K is bonded in a body-centered cubic geometry to eight equivalent P atoms. All K–P bond lengths are 3.44 Å. Ir is bonded to four equivalent P atoms to form a mixture of distorted corner and edge-sharing IrP4 tetrahedra. All Ir–P bond lengths are 2.37 Å. P is bonded in a 8-coordinate geometry to four equivalent K and four equivalent Ir atoms.
K(MoSe)3 crystallizes in the hexagonal P6_3/m space group. The structure is three-dimensional. K is bonded in a 9-coordinate geometry to nine equivalent Se atoms. There are three shorter (3.50 Å) and six longer (3.53 Å) K–Se bond lengths. Mo is bonded in a distorted see-saw-like geometry to four equivalent Se atoms. There are two shorter (2.65 Å) and two longer (2.73 Å) Mo–Se bond lengths. Se is bonded to three equivalent K and four equivalent Mo atoms to form a mixture of distorted edge, face, and corner-sharing SeK3Mo4 hexagonal pyramids.
K(SiO2)2 crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. K is bonded in a trigonal planar geometry to three equivalent O atoms. All K–O bond lengths are 3.18 Å. Si is bonded to four O atoms to form corner-sharing SiO4 tetrahedra. There is three shorter (1.66 Å) and one longer (1.67 Å) Si–O bond length. There are two inequivalent O sites. In the first O site, O is bonded in a linear geometry to two equivalent Si atoms. In the second O site, O is bonded in a linear geometry to three equivalent K and two equivalent Si atoms.
K(MoTe)3 crystallizes in the hexagonal P6_3/m space group. The structure is three-dimensional. K is bonded in a 9-coordinate geometry to nine equivalent Te atoms. There are six shorter (3.71 Å) and three longer (3.72 Å) K–Te bond lengths. Mo is bonded in a 10-coordinate geometry to six equivalent Mo and four equivalent Te atoms. There are two shorter (2.67 Å) and four longer (2.78 Å) Mo–Mo bond lengths. There are two shorter (2.84 Å) and two longer (2.89 Å) Mo–Te bond lengths. Te is bonded in a 7-coordinate geometry to three equivalent K and four equivalent Mo atoms.
K(Nb2Cl5)4 crystallizes in the monoclinic Pm space group. The structure is three-dimensional. there are three inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a distorted q6 geometry to ten Cl1- atoms. There are a spread of K–Cl bond distances ranging from 3.29–3.49 Å. In the second K1+ site, K1+ is bonded in a distorted q6 geometry to ten Cl1- atoms. There are a spread of K–Cl bond distances ranging from 3.28–3.49 Å. In the third K1+ site, K1+ is bonded in a distorted q6 geometry to ten Cl1- atoms. There are a spread of K–Cl bond distances ranging from 3.29–3.48 Å. There are fourteen inequivalent Nb+2.38+ sites. In the first Nb+2.38+ site, Nb+2.38+ is bonded to five Cl1- atoms to form corner-sharing NbCl5 square pyramids. There are a spread of Nb–Cl bond distances ranging from 2.44–2.70 Å. In the second Nb+2.38+ site, Nb+2.38+ is bonded to five Cl1- atoms to form corner-sharing NbCl5 square pyramids. There are a spread of Nb–Cl bond distances ranging from 2.46–2.70 Å. In the third Nb+2.38+ site, Nb+2.38+ is bonded to five Cl1- atoms to form corner-sharing NbCl5 square pyramids. There are a spread of Nb–Cl bond distances ranging from 2.46–2.71 Å. In the fourth Nb+2.38+ site, Nb+2.38+ is bonded to five Cl1- atoms to form corner-sharing NbCl5 square pyramids. There are a spread of Nb–Cl bond distances ranging from 2.46–2.70 Å. In the fifth Nb+2.38+ site, Nb+2.38+ is bonded to five Cl1- atoms to form corner-sharing NbCl5 square pyramids. There are a spread of Nb–Cl bond distances ranging from 2.46–2.64 Å. In the sixth Nb+2.38+ site, Nb+2.38+ is bonded to five Cl1- atoms to form corner-sharing NbCl5 square pyramids. There are four shorter (2.49 Å) and one longer (2.67 Å) Nb–Cl bond lengths. In the seventh Nb+2.38+ site, Nb+2.38+ is bonded to five Cl1- atoms to form corner-sharing NbCl5 square pyramids. There are a spread of Nb–Cl bond distances ranging from 2.46–2.69 Å. In the eighth Nb+2.38+ site, Nb+2.38+ is bonded to five Cl1- atoms to form corner-sharing NbCl5 square pyramids. There are a spread of Nb–Cl bond distances ranging from 2.47–2.70 Å. In the ninth Nb+2.38+ site, Nb+2.38+ is bonded to five Cl1- atoms to form corner-sharing NbCl5 square pyramids. There are a spread of Nb–Cl bond distances ranging from 2.47–2.70 Å. In the tenth Nb+2.38+ site, Nb+2.38+ is bonded to five Cl1- atoms to form corner-sharing NbCl5 square pyramids. There are a spread of Nb–Cl bond distances ranging from 2.46–2.69 Å. In the eleventh Nb+2.38+ site, Nb+2.38+ is bonded to five Cl1- atoms to form distorted corner-sharing NbCl5 square pyramids. There are a spread of Nb–Cl bond distances ranging from 2.46–2.81 Å. In the twelfth Nb+2.38+ site, Nb+2.38+ is bonded to five Cl1- atoms to form corner-sharing NbCl5 square pyramids. There are a spread of Nb–Cl bond distances ranging from 2.44–2.78 Å. In the thirteenth Nb+2.38+ site, Nb+2.38+ is bonded to five Cl1- atoms to form corner-sharing NbCl5 square pyramids. There are a spread of Nb–Cl bond distances ranging from 2.44–2.67 Å. In the fourteenth Nb+2.38+ site, Nb+2.38+ is bonded to five Cl1- atoms to form corner-sharing NbCl5 square pyramids. There are four shorter (2.46 Å) and one longer (2.70 Å) Nb–Cl bond lengths. There are thirty-four inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a 2-coordinate geometry to two equivalent Nb+2.38+ atoms. In the second Cl1- site, Cl1- is bonded in a 2-coordinate geometry to two equivalent Nb+2.38+ atoms. In the third Cl1- site, Cl1- is bonded in a 2-coordinate geometry to two equivalent Nb+2.38+ atoms. In the fourth Cl1- site, Cl1- is bonded in a 2-coordinate geometry to two equivalent Nb+2.38+ atoms. In the fifth Cl1- site, Cl1- is bonded in a 2-coordinate geometry to two Nb+2.38+ atoms. In the sixth Cl1- site, Cl1- is bonded in a 2-coordinate geometry to two Nb+2.38+ atoms. In the seventh Cl1- site, Cl1- is bonded in a 3-coordinate geometry to one K1+ and two Nb+2.38+ atoms. In the eighth Cl1- site, Cl1- is bonded in a 2-coordinate geometry to two Nb+2.38+ atoms. In the ninth Cl1- site, Cl1- is bonded in a 3-coordinate geometry to one K1+ and two Nb+2.38+ atoms. In the tenth Cl1- site, Cl1- is bonded in a 3-coordinate geometry to one K1+ and two Nb+2.38+ atoms. In the eleventh Cl1- site, Cl1- is bonded in a distorted T-shaped geometry to one K1+ and two Nb+2.38+ atoms. In the twelfth Cl1- site, Cl1- is bonded in a distorted linear geometry to two K1+ and two Nb+2.38+ atoms. In the thirteenth Cl1- site, Cl1- is bonded in a 2-coordinate geometry to two Nb+2.38+ atoms. In the fourteenth Cl1- site, Cl1- is bonded in a 3-coordinate geometry to one K1+ and two Nb+2.38+ atoms. In the fifteenth Cl1- site, Cl1- is bonded in a 3-coordinate geometry to one K1+ and two Nb+2.38+ atoms. In the sixteenth Cl1- site, Cl1- is bonded in a 3-coordinate geometry to one K1+ and two Nb+2.38+ atoms. In the seventeenth Cl1- site, Cl1- is bonded in a 2-coordinate geometry to two Nb+2.38+ atoms. In the eighteenth Cl1- site, Cl1- is bonded in a 2-coordinate geometry to two Nb+2.38+ atoms. In the nineteenth Cl1- site, Cl1- is bonded in a 2-coordinate geometry to two Nb+2.38+ atoms. In the twentieth Cl1- site, Cl1- is bonded in a 2-coordinate geometry to two Nb+2.38+ atoms. In the twenty-first Cl1- site, Cl1- is bonded in a 2-coordinate geometry to two Nb+2.38+ atoms. In the twenty-second Cl1- site, Cl1- is bonded in a 3-coordinate geometry to one K1+ and two Nb+2.38+ atoms. In the twenty-third Cl1- site, Cl1- is bonded in a 3-coordinate geometry to one K1+ and two Nb+2.38+ atoms. In the twenty-fourth Cl1- site, Cl1- is bonded in a 2-coordinate geometry to one K1+ and two Nb+2.38+ atoms. In the twenty-fifth Cl1- site, Cl1- is bonded in a distorted T-shaped geometry to one K1+ and two equivalent Nb+2.38+ atoms. In the twenty-sixth Cl1- site, Cl1- is bonded in a rectangular see-saw-like geometry to two K1+ and two equivalent Nb+2.38+ atoms. In the twenty-seventh Cl1- site, Cl1- is bonded in a 2-coordinate geometry to two Nb+2.38+ atoms. In the twenty-eighth Cl1- site, Cl1- is bonded in a 3-coordinate geometry to one K1+ and two Nb+2.38+ atoms. In the twenty-ninth Cl1- site, Cl1- is bonded in a 3-coordinate geometry to one K1+ and two Nb+2.38+ atoms. In the thirtieth Cl1- site, Cl1- is bonded in a 3-coordinate geometry to one K1+ and two Nb+2.38+ atoms. In the thirty-first Cl1- site, Cl1- is bonded in a distorted bent 120 degrees geometry to two Nb+2.38+ atoms. In the thirty-second Cl1- site, Cl1- is bonded in a distorted bent 120 degrees geometry to two Nb+2.38+ atoms. In the thirty-third Cl1- site, Cl1- is bonded in a distorted bent 120 degrees geometry to two Nb+2.38+ atoms. In the thirty-fourth Cl1- site, Cl1- is bonded in a distorted bent 120 degrees geometry to two Nb+2.38+ atoms.
We present a new ground-based visual transmission spectrum of the hot Jupiter WASP-43b, obtained as part of the ACCESS Survey. The spectrum was derived from four transits observed between 2015 and 2018, with combined wavelength coverage between 5300 and 9000 Å and an average photometric precision of 708 ppm in 230 Å bins. We perform an atmospheric retrieval of our transmission spectrum combined with literature Hubble Space Telescope/WFC3 observations to search for the presence of clouds/hazes as well as Na, K, Hα, and H{sub 2}O planetary absorption and stellar spot contamination over a combined spectral range of 5318–16420 Å. We do not detect a statistically significant presence of Na i or K i alkali lines, or Hα in the atmosphere of WASP-43b. We find that the observed transmission spectrum can be best explained by a combination of heterogeneities on the photosphere of the host star and a clear planetary atmosphere with H{sub 2}O. This model yields a log evidence of 8.26 ± 0.42 higher than a flat (featureless) spectrum. In particular, the observations marginally favor the presence of large, low-contrast spots over the four ACCESS transit epochs with an average covering fraction f{sub het}=0.27{sub −0.16}{sup +0.42} and temperature contrast ΔT = 132 K ± 132 K. Within the planet’s atmosphere, we recover a log H{sub 2}O volume mixing ratio of −2.78{sub −1.47}{sup +1.38}, which is consistent with previous H{sub 2}O abundance determinations for this planet.
We report beam-recoil transferred polarizations for the exclusive electroproduction of K + Λ and K + Σ 0 final states from an unpolarized proton target have been measured using the CLAS12 spectrometer at Jefferson Laboratory. The measurements at beam energies of 6.535 and 7.546 GeV span the range of four-momentum transfer Q 2 from 0.3 to 4.5 GeV 2 and invariant energy W from 1.6 to 2.4 GeV, while covering the full center-of-mass angular range of the K + . These new data extend the existing hyperon polarization data from CLAS in a similar kinematic range but from a significantly larger dataset. They represent an important addition to the world data, allowing for better exploration of the reaction mechanism in strangeness production processes, for further understanding of the spectrum and structure of excited nucleon states, and for improved insight into the strong interaction in the regime of nonperturbative dynamics.
The NA61/SHINE experiment at the CERN Super Proton Synchrotron (SPS) studies the onset of deconfinement in hadron matter by a scan of particle production in collisions of nuclei with various sizes at a set of energies covering the SPS energy range. This paper presents results on inclusive double-differential spectra, transverse momentum and rapidity distributions and mean multiplicities of $\pi^, \pm K^\pm$ p and $\bar{p}$ produced in the 20% most central Be+$^9$ Be collisions at beam momenta of 19A, 30A, 40A, 75A and 150A ${\mathrm{Ge} \mathrm{V}}\!/\!c$. The energy dependence of the $K^\pm/ \pi^\pm$ ratios as well as of inverse slope parameters of the $K^\pm$ transverse mass distributions are close to those found in inelastic $p+p$ reactions. The new results are compared to the world data on $p+p and Pb+Pb collisions as well as to predictions of the Epos , U r qmd , Ampt , Phsd and Smash models.
The production of $K^{0}_{S}$ mesons in inelastic p+p collisions at beam momentum 158 $\text{ GeV }/c$ ($\sqrt{s_{NN}}=17.3$ $\text{ GeV }$) was measured with the NA61/SHINE spectrometer at the CERN Super Proton Synchrotron. Double-differential distributions were obtained in transverse momentum and rapidity. The mean multiplicity of $K^{0}_{S}$ was determined to be $0.162 \pm 0.001 (stat.) \pm 0.011 (sys.)$. The results on $K^{0}_{S}$ production are compared with model predictions (EPOS 1.99, SMASH 2.0, PHSD and UrQMD 3.4 models) as well as with published world data.
Abstract We report results from a study ofB ± → DK ± decays followed byDdecaying to theCP-even final stateK + K − and CP-odd final state$$ {K}_S^0{\pi}^0 $$ K S 0 π 0 , whereDis an admixture ofD 0 and$$ {\overline{D}}^0 $$ D ¯ 0 states. These decays are sensitive to the Cabibbo-Kobayashi-Maskawa unitarity-triangle angleϕ 3 . The results are based on a combined analysis of the final data set of 772×10 6 $$ B\overline{B} $$ B B ¯ pairs collected by the Belle experiment and a data set of 198×10 6 $$ B\overline{B} $$ B B ¯ pairs collected by the Belle II experiment, both in electron-positron collisions at the Υ(4S) resonance. We measure the CP asymmetries to be$$ \mathcal{A} $$ A CP+ = (+12.5±5.8±1.4)% and$$ \mathcal{A} $$ A CP− = (−16.7±5.7±0.6)%, and the ratios of branching fractions to be$$ \mathcal{R} $$ R CP+ = 1.164±0.081±0.036 and$$ \mathcal{R} $$ R CP− = 1.151±0.074±0.019. The first contribution to the uncertainties is statistical, and the second is systematic. The asymmetries$$ \mathcal{A} $$ A CP+ and$$ \mathcal{A} $$ A CP− have similar magnitudes and opposite signs; their difference corresponds to 3.5 standard deviations. From these values we calculate 68.3% confidence intervals of (8.5 ° <ϕ 3 < 16.5 ° ) or (84.5 ° <ϕ 3 < 95.5 ° ) or (163.3 ° <ϕ 3 < 171.5 ° ) and 0.321 B< 0.465.
Searches for exclusive decays of the Higgs boson into D*$\gamma$ and of the Z boson into D 0 $\gamma$ and K$_{s}^{0}$$\gamma$ can probe flavour-violating Higgs boson and Z boson couplings to light quarks. Searches for these decays are performed with a pp collision data sample corresponding to an integrated luminosity of 136.3 fb -1 collected at $\sqrt{s}$ = 13TeV between 2016–2018 with the ATLAS detector at the CERN Large Hadron Collider. In the D*$\gamma$ and D 0 $\gamma$ channels, the observed (expected) 95% confidence-level upper limits on the respective branching fractions are B(H→D*$\gamma$) < 1.0(1.2)×10 -3 , B(Z→D 0 $\gamma$) < 4.0(3.4)×10 -6 , while the corresponding results in the K$_{s}^{0}$$\gamma$ channel are B(Z→K$_{s}^{0}$$\gamma$) < 3.1(3.0)×10 -6 .
Two-particle correlations are presented for $K^0_S$, $Λ$, and $\overline{Λ}$ strange hadrons as a function of relative momentum in lead-lead collisions at a nucleon-nucleon center-of-mass energy of 5.02 TeV. The dataset corresponds to an integrated luminosity of 0.607 nb -1 and was collected using the CMS detector at the CERN LHC. These correlations are sensitive to quantum statistics and to final-state interactions between the particles. The source size extracted from the $K^0_S$$K^0_S$ correlations is found to decrease from 4.6 to 1.6 fm in going from central to peripheral collisions. Strong interaction scattering parameters (i.e., scattering length and effective range) are determined from the $ΛK^0_S$ and $ΛΛ$ (including their charge conjugates) correlations using the Lednický–Lyuboshitz model and are compared to theoretical and other experimental results.
Abstract Using (27.12±0.14)×10 8 ψ(3686) events collected with the BESIII detector at BEPCII, the decay ofψ(3686)→$$ {\varOmega}^{-}{K}^{+}{\overline{\Xi}}^0 $$ Ω − K + Ξ ¯ 0 + c.c.is observed for the first time. The branching fraction of this decay is measured to be$$ {\mathcal{B}}_{\psi (3686)\to {\varOmega}^{-}{K}^{+}{\overline{\Xi}}^0+\textrm{c}.\textrm{c}.} $$ B ψ 3686 → Ω − K + Ξ ¯ 0 + c . c . = (2.78 ± 0.40 ± 0.18) × 10 −6 , where the first uncertainty is statistical and the second is systematic. Possible baryon excited states are searched for in this decay, but no evident intermediate state is observed with the current sample size.
The production of strange hadrons ($K^{0}_{S}$, Λ, Ξ ± , and Ω ± ), baryon-to-meson ratios (Λ/$K^{0}_{S}$, Ξ/$K^{0}_{S}$, and Ω/$K^{0}_{S}$), and baryon-to-baryon ratios (Ξ/Λ, Ω/Λ, and Ω/Ξ) associated with jets and the underlying event were measured as a function of transverse momentum (p T ) in pp collisions at $\sqrt{s}$ = 13 TeV and p Pb collisions at $\sqrt{s_{NN}}$ = 5.02 TeV with the ALICE detector at the LHC. The inclusive production of the same particle species and the corresponding ratios are also reported. The production of multi-strange hadrons, Ξ ± and Ω ± , and their associated particle ratios in jets and in the underlying event are measured for the first time. In both pp and p–Pb collisions, the baryon-to-meson and baryon-to-baryon yield ratios measured in jets differ from the inclusive particle production for low and intermediate hadron p T (0.6–6 GeV/c). Ratios measured in the underlying event are in turn similar to those measured for inclusive particle production. In pp collisions, the particle production in jets is compared with P YTHIA 8 predictions with three colour-reconnection implementation modes. None of them fully reproduces the data in the measured hadron p T region. The maximum deviation is observed for Ξ ± and Ω ± which reaches a factor of about six. The event multiplicity dependence is further investigated in p–Pb collisions. In contrast to what is observed in the underlying event, there is no significant event-multiplicity dependence for particle production in jets. The presented measurements provide novel constraints on hadronisation and its Monte Carlo description. In particular, they demonstrate that the fragmentation of jets alone is insufficient to describe the strange and multi-strange particle production in hadronic collisions at LHC energies.
K-12 schools are the largest energy consumers in the public sector, with their HVAC energy consumption representing the largest portion of their total energy use. While transitioning these schools to grid-interactive HVAC system operation through advanced controls offers significant financial and environmental benefits, and model predictive control (MPC) has been identified as a promising solution to achieve that, very few MPCs are affordable and have been deployed in K-12 schools. This situation raises concerns about the unclear real-world benefits of MPC technology among facility managers and industries. To address this gap, this paper presents a low-cost MPC solution that requires minimal control infrastructure costs and a unique field demonstration at a K-12 school, conducted for both cooling and heating seasons. This work adopted a previously developed MPC and extended it for use in the school application. The MPC aims to coordinate multiple packaged units to eliminate unnecessary peaks and shift cooling or heating loads in response to grid signals based on load conditions, while maintaining thermostat temperatures within school-defined bounds. Throughout the field tests, the MPC achieved a 24% reduction in peak demand during the cooling season and shifted cooling or heating loads by up to 16% in response to the school's utility tariff, considering load conditions, while also allowing end-users to override thermostat setpoints. Further, the paper also discusses the limitations of this study and future research directions for better performance of the MPC at K-12 schools.
Here, the high-temperature compression behavior of lithium fluoride (LiF) has been determined to ∼80 GPa and 2300 K by means of high-resolution synchrotron-based x-ray diffraction in a laser-heated diamond-anvil cell. The room-temperature Vinet equation of state (EOS) for LiF yields an isothermal room-temperature, ambient-pressure lattice parameter a 0 = 4.028 (±0.003) Å, volume V 0 = 65.35 (±0.03) Å 3 , bulk modulus K 0 = 67.57 (±0.34) GPa, and its pressure derivative K 0 ’ = 4.64 (±0.03). This expanded experimental dataset is in good agreement with the LiF thermal equation of state by Myint et al. (2019) up to ∼2300 K and 25 GPa. At higher pressures and temperatures our data shows reduced thermal expansion compared to the prediction and may be particularly important for experiments at more extreme conditions.
The first search for ultra-rare K + decays into the π + e + e - e + e - final state is reported, using a dataset collected by the NA62 experiment at CERN in 2017–2018. An upper limit of 1.4 x 10 -8 at 90% CL is obtained for the branching ratio of the K + → π + e + e - e + e - decay, predicted in the Standard Model to be (7.2 ± 0.7) x 10 -11 . Upper limits at 90% CL are obtained at the level of 10 -9 for the branching ratios of two prompt decay chains involving pair-production of hidden-sector mediators: K + → π + aa,a → e + e - and K + → π + S,S → A'A',A' → e + e - .