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M. Ablikim, М. Н. Ачасов, P. Adlarson, S. Ahmed, M. Albrecht, A. Amoroso, Q. An, Anita, Y. Bai, O. Bakina, R. Baldini Ferroli, I. Balossino, Y. Ban, K. Begzsuren, J. V. Bennett, N. Berger, M. Bertani, D. Bettoni, F. Bianchi, J. Biernat, J. Bloms, I. Boyko, R. A. Briere, H. Cai, X. Cai, A. Calcaterra, G. F. Cao, N. Cao, S. A. Çetin, J. F. Chang, W. L. Chang, G. Chelkov, D. Y. Chen, G. Chen, H. S. Chen, M. L. Chen, S. J. Chen, X. R. Chen, Y. B. Chen, W. Cheng, G. Cibinetto, F. Cossio, X. F. Cui, H. L. Dai, J. P. Dai, X. Dai, A. Dbeyssi, D. Dedovich, Z. Y. Deng, A. Denig, I. Denysenko, M. Destefanis, F. De Mori, Y. Ding, C. Dong, J. Dong, L. Y. Dong, M. Y. Dong, S. X. Du, J. Fang, S. S. Fang, Y. Fang, R. Farinelli, L. Fava, F. Feldbauer, G. Felici, C. Q. Feng, M. Fritsch, C. D. Fu, Y. Fu, X. L. Gao, Y. Gao, Y. Gao, Y. Gao, I. Garzia, E. Gersabeck, A. Gilman, K. Goetzen, L. Gong, W. X. Gong, W. Gradl, M. Greco, L. Gu, M. H. Gu, S. Gu, Y. T. Gu, C. Y. Guan, A. Q. Guo, L. B. Guo, R. P. Guo, Yahui Guo, Yahui Guo, A. Guskov, S. Han, T. T. Han, T. Z. Han, X. Q. Hao, F. A. Harris, K. L. He, F. H. Heinsius
Abstract
A partial-wave analysis is performed for the process ${e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}{K}^{+}{K}^{\ensuremath{-}}{\ensuremath{\pi}}^{0}{\ensuremath{\pi}}^{0}$ at the center-of-mass energies ranging from 2.000 to 2.644 GeV. The data samples of ${e}^{+}{e}^{\ensuremath{-}}$ collisions, collected by the BESIII detector at the BEPCII collider with a total integrated luminosity of $300\text{ }\text{ }{\mathrm{pb}}^{\ensuremath{-}1}$, are analyzed. The total Born cross sections for the process ${e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}{K}^{+}{K}^{\ensuremath{-}}{\ensuremath{\pi}}^{0}{\ensuremath{\pi}}^{0}$, as well as the Born cross sections for the subprocesses ${e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}\ensuremath{\phi}{\ensuremath{\pi}}^{0}{\ensuremath{\pi}}^{0}$, ${K}^{+}(1460){K}^{\ensuremath{-}}$, ${K}_{1}^{+}(1400){K}^{\ensuremath{-}}$, ${K}_{1}^{+}(1270){K}^{\ensuremath{-}}$, and ${K}^{*+}(892){K}^{*\ensuremath{-}}(892)$, are measured versus the center-of-mass energy. The corresponding results for ${e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}{K}^{+}{K}^{\ensuremath{-}}{\ensuremath{\pi}}^{0}{\ensuremath{\pi}}^{0}$ and $\ensuremath{\phi}{\ensuremath{\pi}}^{0}{\ensuremath{\pi}}^{0}$ are consistent with those of BABAR with better precision. By analyzing the cross sections for the four subprocesses, ${K}^{+}(1460){K}^{\ensuremath{-}}$, ${K}_{1}^{+}(1400){K}^{\ensuremath{-}}$, ${K}_{1}^{+}(1270){K}^{\ensuremath{-}}$, and ${K}^{*+}(892){K}^{*\ensuremath{-}}(892)$, a structure with mass $M=(2126.5\ifmmode\pm\else\textpm\fi{}16.8\ifmmode\pm\else\textpm\fi{}12.4)\text{ }\text{ }\mathrm{MeV}/{c}^{2}$ and width $\mathrm{\ensuremath{\Gamma}}=(106.9\ifmmode\pm\else\textpm\fi{}32.1\ifmmode\pm\else\textpm\fi{}28.1)\text{ }\text{ }\mathrm{MeV}$ is observed with an overall statistical significance of $6.3\ensuremath{\sigma}$, although with very limited significance in the subprocesses ${e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}{K}_{1}^{+}(1270){K}^{\ensuremath{-}}$ and ${K}^{*+}(892){K}^{*\ensuremath{-}}(892)$. The resonant parameters of the observed structure suggest it can be identified with the $\ensuremath{\phi}(2170)$, thus the results provide valuable input to the internal nature of the $\ensuremath{\phi}(2170)$.