This study investigates $$B^*_{s,d}\rightarrow \mu ^+\mu ^-$$ in the dimuon distributions and the hadronic contribution $$B_{s,d}\rightarrow B^*_{s,d}\gamma \rightarrow \mu ^+\mu ^-$$ . The $$\mu ^+\mu ^-$$ decay widths of the vector mesons $$B^*_{s,d}$$ are approximately a factor of 700 larger than the corresponding scalar mesons $$B_{s,d}$$ . The ratio of the branching fractions obtained, $$\frac{Br({B_{s,d}^*\rightarrow \mu ^+\mu ^-})}{{Br({B_{s,d}\rightarrow \mu ^+\mu ^-})}}$$ , is approximately $$\frac{0.3\times \mathrm{eV}}{{\Gamma (B^*_{s,d}\rightarrow B_{s,d}\gamma )}}$$ . The hadronic contribution $$B_{s,d}\rightarrow B^*_{s,d}\gamma \rightarrow \mu ^+\mu ^-$$ is also estimated. The relative increase in the $$B_{s,d}\rightarrow \mu ^+\mu ^-$$ amplitude is approximately $$(0.01\pm 0.006) \sqrt{\frac{{\Gamma (B^*_{s,d}\rightarrow B_{s,d} \gamma )}}{{100~\mathrm{eV}}}}$$ . If we select $$\Gamma (B^*_{s,d}\rightarrow B_{s,d}\gamma )=2~$$ eV, then the branching fractions of the vector mesons to the lepton pair are $$5.3\times 10^{-10}$$ and $$1.6\times 10^{-11}$$ for $$B^*_{s}$$ and $$B^*_{d}$$ , respectively. If we select $$\Gamma (B^*_{s,d}\rightarrow B_{s,d}\gamma )=200~$$ eV, then the updated branching fractions of the scalar mesons to the muon pair are $$(3.78\,\pm \,0.25)\times 10^{-9}$$ and $$(1.09\,\pm \,0.09)\times 10^{-10}$$ for $$B_{s}$$ and $$B_{d}$$ , respectively. If we select the recent predicted M1 widths $$\Gamma (B^*_{s,d}\rightarrow B_{s,d}\gamma )=313, 1230$$ eV ( arXiv:1607.02169 ), then the updated branching fractions are $$(3.8\,\pm \,0.3)\times 10^{-9}$$ and $$(1.2\,\pm \,0.1)\times 10^{-10}$$ for $$B_{s}\rightarrow \mu ^+\mu ^-$$ and $$B_{d}\rightarrow \mu ^+\mu ^-$$ , respectively. Further studies on $$B^*_{s,d}$$ , including those on dielectron decay and two-body decay with $$J/\psi $$ , should be conducted.
The studies on various analysis and detection methods have shown that the constitution and disseminated relationship of carbonate zinc oxide ore are very complex.The plumbic and zinc mineral,ferric oxide mineral,clay mineral paragenesis and the selective absorption of ferric oxide mineral to zinc are the main reason why it is difficult to flotate zinc oxide.This paper suggests that H 2SO 4 leach process is an effective method for processing zinc oxide.
An integrated energy system (IES) is vulnerable to network attacks due to the coupling features of multi-energy systems, as well as the deep integration between a physical system and an information system. The anomaly detection of the time-series data in an IES is a key problem to defend against network attacks and ensure the cyber-physical security of IES. Aiming at false data injection attacks (FDIAs) on IES, this paper proposes an anomaly detection method for time-series data in a cyber-physical integrated energy system based on time-frequency feature prediction. The time-frequency features of the time-series data are extracted based on three time-frequency transform methods (DWT, EMD, and EWT). Then the extracted time-frequency features are input to the autoencoder (AE) to capture the hidden features and nonlinear structure of the original data in the frequency domain. The time-domain data within the detected time period are predicted by applying regression prediction on the top-layer features of AE. Considering the uncertainty of regression prediction, kernel density estimation (KDE) is used to estimate the probability density function of prediction error and the interval of the predicted data is estimated accordingly. The estimated lower boundary value of the predicted data is selected as the attack judgment threshold for anomaly detection. The results of the case study verify the advantages of the proposed method in reducing the false positive rate and improving the anomaly detection accuracy.
Polyacrylamide nanoparticles attracted increasing interest as profile control agents in oilfield development owing to the characteristics of deformation and continuous expansion in core pore. In this article, the structure and morphology of polyacrylamide nanoparticles were characterized by Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). And the fluorescence microscopy and core displacement equipment were used to evaluate the properties of the expansion and plugging properties. Results showed that the nanoparticles prepared by inverse emulsion polymerization can be able to pass through the pores in the rocks due to the uniform particle size which is less than 500 nm. When the nanoparticles were in contact with water for 72 hours, the average particle size increased to 12.2 μ m. The water-swelled nanoparticles can effectively block the high-permeability layer and improve the oil recovery in the low-permeability layer. The results obtained in this paper reveal the mechanism of elastic deformation and expansion characteristics of polyacrylamide nanoparticles, and further prove the great potential of nanoparticles to enhance oil recovery in the development of low permeability oilfields.
Kerr-Newman de Sitter (KNdS) spacetimes have a rich thermodynamic structure that involves multiple horizons, and so differs in key respects from asymptotically flat or AdS black holes. In this paper, we show that certain features of KNdS spacetimes can be reproduced by a constrained system of $N$ non-interacting spins in a magnetic field. Both the KNdS and spin systems have bounded energy and entropy, a maximum of the entropy in the interior of the energy range, and a symmetry that maps lower energy states to higher energy states with the same entropy. Consequently, both systems have a temperature that can be positive or negative, where the gravitational temperature is defined analogously to that of the spins. We find that the number of spins $N$ corresponds to $1/\Lambda$ for black holes with very small charge $q$ and rotation parameter $a$, and scales like $\sqrt{(a^2+q^2)/\Lambda}$ for larger values of $a$ and $q$. By studying constrained spin systems, we provide insight into the thermodynamics of KNdS spacetimes and its quantum mechanical description.
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