Nine-channel unitary three-body fits to COMPASS lineshapes reproduce the a1(1420) enhancement by triangle singularity without requiring a genuine a1(1420) pole.
Systematic study of the singularity mechanism in heavy quarkonium decays
3 Pith papers cite this work. Polarity classification is still indexing.
abstract
We investigate in detail the role of heavy meson loops in the transition from $J^{PC}=1^{--}$ sources to candidates for QCD "exotics", such as $Z_c(3900)$, $Z_b(10610)$ and $Z_b'(10650)$. We demonstrate that, if a vector state strongly couples to a heavy meson pair in an $S$--wave and this system decays to another heavy meson pair (e.g. via pion emission), again in an $S$-wave, the pertinent diagrams get enhanced significantly, if the intermediate states are (near) on--shell and have small relative momenta. In a limited kinematic range this mechanism generates "singularity regions" that lead to the creation of a large number of low energy heavy meson pairs, providing an ideal environment for the formation of hadron-hadron bound states or resonances. For instance, we predict that the signals for $Z_b$ and $Z_b'$ should be a lot stronger in $\Upsilon(6S)$ decays due to this mechanism, if these states are indeed hadron-hadron resonances. The findings of this work should be valuable for deepening our understanding of the nature of the mentioned states.
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A framework maps erosion distributions to Wasserstein space, uses basis expansion to create a multivariate random field, and applies local regression plus Kriging to predict distributions and their functionals at new locations, outperforming alternatives in simulations and applied to Shaanxi provinc
Joint analysis of experimental and lattice data confirms Z_c(3900) and Z_cs(3985) as SU(3) flavor partners with pole masses (3879.6 ± 4.8) MeV and (3976.9 ± 5.1) MeV, half-widths (32.2 ± 4.7) MeV and (28.8 ± 5.9) MeV, both resonances.
citing papers explorer
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The $a_1(1420)$ in a Unitary Coupled-Channel Three-Body Approach
Nine-channel unitary three-body fits to COMPASS lineshapes reproduce the a1(1420) enhancement by triangle singularity without requiring a genuine a1(1420) pole.
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Spatial Prediction of Local Soil Erosion Distribution in the Wasserstein Space
A framework maps erosion distributions to Wasserstein space, uses basis expansion to create a multivariate random field, and applies local regression plus Kriging to predict distributions and their functionals at new locations, outperforming alternatives in simulations and applied to Shaanxi provinc
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Determination of the $Z_c(3900)$ and the $Z_{cs}(3985)$ states from joint analysis of experimental and lattice data
Joint analysis of experimental and lattice data confirms Z_c(3900) and Z_cs(3985) as SU(3) flavor partners with pole masses (3879.6 ± 4.8) MeV and (3976.9 ± 5.1) MeV, half-widths (32.2 ± 4.7) MeV and (28.8 ± 5.9) MeV, both resonances.