5,789 research outputs found
Semileptonic and decays involving scalar and axial-vector mesons
We report our theoretical calculations on the branching fractions for the
semileptonic and decays, i.e., , where and denote the pseudoscalar and vector mesons,
respectively, while denotes the scalar meson with mass above 1 GeV and
the axial-vector meson. The branching fractions for the semileptonic
and modes have been measured very well in experiment and our theoretical
values are in good agreement with them. The ones for and modes are
our theoretical predictions. There is little experimental information on the
semileptonic decays although much theoretical effort has been done. In
addition, we predict the branching fractions of and as and , in order, assuming them
as the conventional mesons with quark-antiquark configuration. The high
luminosity collider SuperKEKB/Belle-II is running, with the data
sample enhanced by a factor of 40 compared to Belle, which will provide huge
opportunity for the test of the theoretical predictions and further help
understand the inner structure of these scalar and axial vector mesons, e.g.,
the glueball content of and the mixing angles for the axial-vector
mesons. These decay channels can also be accessed by the LHCb experiment.Comment: final version, will appear in EPJC, one more reference adde
Poly[[aquatris(μ-benzene-1,4-dicarboxylato)tricobalt(II)] methanol monosolvate monohydrate]
The asymmetric unit of the title compound, {[Co3(C8H4O4)3(H2O)]·CH3OH·H2O}n, consists of four crystallographically independent Co cations, four benzene-1,4-dicarboxylate (bdc) anions, two water and one methanol solvent molecule. Two of the Co cations and two of the bdc anions are located on centres of inversion, whereas all other atoms are located in general positions. In the crystal, two Co atoms are only fourfold coordinated by three O atoms from three bdc ligands and by one O atom from one coordinated water molecule, while a third Co atom is coordinated by four O atoms from four bdc ligands within a strongly distorted tetrahedral geometry. The other two Co cations are octahedrally coordinated by six O atoms from six bdc anions. The Co cations are linked by the bdc anions into a three-dimensional framework. From this arrangement, cavities are formed in which additional methanol and water molecules are embedded
Ultra Dual-Path Compression For Joint Echo Cancellation And Noise Suppression
Echo cancellation and noise reduction are essential for full-duplex
communication, yet most existing neural networks have high computational costs
and are inflexible in tuning model complexity. In this paper, we introduce
time-frequency dual-path compression to achieve a wide range of compression
ratios on computational cost. Specifically, for frequency compression,
trainable filters are used to replace manually designed filters for dimension
reduction. For time compression, only using frame skipped prediction causes
large performance degradation, which can be alleviated by a post-processing
network with full sequence modeling. We have found that under fixed compression
ratios, dual-path compression combining both the time and frequency methods
will give further performance improvement, covering compression ratios from 4x
to 32x with little model size change. Moreover, the proposed models show
competitive performance compared with fast FullSubNet and DeepFilterNet. A demo
page can be found at
hangtingchen.github.io/ultra_dual_path_compression.github.io/.Comment: Accepted by Interspeech 202
Detecting Extra Dimension by Helium-like Ions
Considering that gravitational force might deviate from Newton's
inverse-square law and become much stronger in small scale, we present a method
to detect the possible existence of extra dimensions in the ADD model. By
making use of an effective variational wave function, we obtain the
nonrelativistic ground energy of a helium atom and its isoelectronic sequence.
Based on these results, we calculate gravity correction of the ADD model. Our
calculation may provide a rough estimation about the magnitude of the
corresponding frequencies which could be measured in later experiments.Comment: 8 pages, no figures, accepted by Mod. Phys. Lett.
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