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Observation of the $W$ -annihilation decay $D_{s}^{+} \to ω π^{+}$ and evidence for $D_{s}^{+} \to ω K^{+}$

M. Ablikim¹, M. N. Achasov^10,d, S. Ahmed¹⁵, M. Albrecht⁴, M. Alekseev^56a,56c, A. Amoroso^56a,56c, F. F. An¹, Q. An^53,43, Y. Bai⁴² et al. (BESIII Collaboration)

Y. Bai⁴², O. Bakina²⁷, R. Baldini Ferroli^23a, Y. Ban³⁵, K. Begzsuren²⁵, D. W. Bennett²², J. V. Bennett⁵, N. Berger²⁶, M. Bertani^23a, D. Bettoni^24a, F. Bianchi^56a,56c, E. Boger^27,b, I. Boyko²⁷, R. A. Briere⁵, H. Cai⁵⁸, X. Cai^1,43, O. Cakir^46a, A. Calcaterra^23a, G. F. Cao^1,47, S. A. Cetin^46b, J. Chai^56c, J. F. Chang^1,43, W. L. Chang^1,47, G. Chelkov^27,b,c, G. Chen¹, H. S. Chen^1,47, J. C. Chen¹, M. L. Chen^1,43, P. L. Chen⁵⁴, S. J. Chen³³, Y. B. Chen^1,43, W. Cheng^56c, G. Cibinetto^24a, F. Cossio^56c, H. L. Dai^1,43, J. P. Dai^38,h, A. Dbeyssi¹⁵, D. Dedovich²⁷, Z. Y. Deng¹, A. Denig²⁶, I. Denysenko²⁷, M. Destefanis^56a,56c, F. De Mori^56a,56c, Y. Ding³¹, C. Dong³⁴, J. Dong^1,43, L. Y. Dong^1,47, M. Y. Dong^1,43,47, Z. L. Dou³³, S. X. Du⁶¹, P. F. Duan¹, J. Z. Fan⁴⁵, J. Fang^1,43, S. S. Fang^1,47, Y. Fang¹, R. Farinelli^24a,24b, L. Fava^56b,56c, S. Fegan²⁶, F. Feldbauer⁴, G. Felici^23a, C. Q. Feng^53,43, M. Fritsch⁴, C. D. Fu¹, Y. Fu¹, Q. Gao¹, X. L. Gao^53,43, Y. Gao⁴⁵, Y. G. Gao⁶, Z. Gao^53,43, B. Garillon²⁶, I. Garzia^24a, A. Gilman⁵⁰, K. Goetzen¹¹, L. Gong³⁴, W. X. Gong^1,43, W. Gradl²⁶, M. Greco^56a,56c, L. M. Gu³³, M. H. Gu^1,43, S. Gu², Y. T. Gu¹³, A. Q. Guo¹, L. B. Guo³², R. P. Guo^1,47, Y. P. Guo²⁶, A. Guskov²⁷, Z. Haddadi²⁹, S. Han⁵⁸, X. Q. Hao¹⁶, F. A. Harris⁴⁸, K. L. He^1,47, F. H. Heinsius⁴, T. Held⁴, Y. K. Heng^1,43,47, T. Holtmann⁴, Z. L. Hou¹, H. M. Hu^1,47, J. F. Hu^38,h, T. Hu^1,43,47, Y. Hu¹, G. S. Huang^53,43, J. S. Huang¹⁶, X. T. Huang³⁷, X. Z. Huang³³, T. Hussain⁵⁵, W. Ikegami Andersson⁵⁷, M. Irshad^53,43, Q. Ji¹, Q. P. Ji¹⁶, X. B. Ji^1,47, X. L. Ji^1,43, X. S. Jiang^1,43,47, X. Y. Jiang³⁴, J. B. Jiao³⁷, Z. Jiao¹⁸, D. P. Jin^1,43,47, S. Jin^1,47, Y. Jin⁴⁹, T. Johansson⁵⁷, A. Julin⁵⁰, N. Kalantar-Nayestanaki²⁹, X. S. Kang³⁴, M. Kavatsyuk²⁹, B. C. Ke¹, T. Khan^53,43, A. Khoukaz⁵¹, P. Kiese²⁶, R. Kiuchi¹, R. Kliemt¹¹, L. Koch²⁸, O. B. Kolcu^46b,f, B. Kopf⁴, M. Kornicer⁴⁸, M. Kuemmel⁴, M. Kuessner⁴, A. Kupsc⁵⁷, M. Kurth¹, W. Kühn²⁸, J. S. Lange²⁸, M. Lara²², P. Larin¹⁵, L. Lavezzi^56c, S. Leiber⁴, H. Leithoff²⁶, C. Li⁵⁷, Cheng Li^53,43, D. M. Li⁶¹, F. Li^1,43, F. Y. Li³⁵, G. Li¹, H. B. Li^1,47, H. J. Li^1,47, J. C. Li¹, J. W. Li⁴¹, Ke Li¹, Lei Li³, P. L. Li^53,43, P. R. Li^47,7, Q. Y. Li³⁷, T. Li³⁷, W. D. Li^1,47, W. G. Li¹, X. L. Li³⁷, X. N. Li^1,43, X. Q. Li³⁴, Z. B. Li⁴⁴, H. Liang^53,43, Y. F. Liang⁴⁰, Y. T. Liang²⁸, G. R. Liao¹², L. Z. Liao^1,47, J. Libby²¹, C. X. Lin⁴⁴, D. X. Lin¹⁵, B. Liu^38,h, B. J. Liu¹, C. X. Liu¹, D. Liu^53,43, D. Y. Liu^38,h, F. H. Liu³⁹, Fang Liu¹, Feng Liu⁶, H. B. Liu¹³, H. L. Liu⁴², H. M. Liu^1,47, Huanhuan Liu¹, Huihui Liu¹⁷, J. B. Liu^53,43, J. Y. Liu^1,47, K. Liu⁴⁵, K. Y. Liu³¹, Ke Liu⁶, Q. Liu⁴⁷, S. B. Liu^53,43, X. Liu³⁰, Y. B. Liu³⁴, Z. A. Liu^1,43,47, Zhiqing Liu²⁶, Y. F. Long³⁵, X. C. Lou^1,43,47, H. J. Lu¹⁸, J. D. Lu^1,47, J. G. Lu^1,43, Y. Lu¹, Y. P. Lu^1,43, C. L. Luo³², M. X. Luo⁶⁰, T. Luo^9,j, X. L. Luo^1,43, S. Lusso^56c, X. R. Lyu⁴⁷, F. C. Ma³¹, H. L. Ma¹, L. L. Ma³⁷, M. M. Ma^1,47, Q. M. Ma¹, X. N. Ma³⁴, X. X. Ma^1,47, X. Y. Ma^1,43, Y. M. Ma³⁷, F. E. Maas¹⁵, M. Maggiora^56a,56c, S. Maldaner²⁶, Q. A. Malik⁵⁵, A. Mangoni^23b, Y. J. Mao³⁵, Z. P. Mao¹, S. Marcello^56a,56c, Z. X. Meng⁴⁹, J. G. Messchendorp²⁹, G. Mezzadri^24a, J. Min^1,43, T. J. Min¹, R. E. Mitchell²², X. H. Mo^1,43,47, Y. J. Mo⁶, C. Morales Morales¹⁵, G. Morello^23a, N. Yu. Muchnoi^10,d, H. Muramatsu⁵⁰, A. Mustafa⁴, S. Nakhoul^11,g, Y. Nefedov²⁷, F. Nerling^11,g, I. B. Nikolaev^10,d, Z. Ning^1,43, S. Nisar^8,l, S. L. Niu^1,43, S. L. Olsen^36,k, Q. Ouyang^1,43,47, S. Pacetti^23b, Y. Pan^53,43, M. Papenbrock⁵⁷, P. Patteri^23a, M. Pelizaeus⁴, J. Pellegrino^56a,56c, H. P. Peng^53,43, K. Peters^11,g, J. Pettersson⁵⁷, J. L. Ping³², R. G. Ping^1,47, A. Pitka⁴, R. Poling⁵⁰, V. Prasad^53,43, H. R. Qi², M. Qi³³, T. Y. Qi², S. Qian^1,43, C. F. Qiao⁴⁷, N. Qin⁵⁸, X. S. Qin⁴, Z. H. Qin^1,43, J. F. Qiu¹, K. H. Rashid^55,i, K. Ravindran²¹, C. F. Redmer²⁶, M. Richter⁴, M. Ripka²⁶, A. Rivetti^56c, M. Rolo^56c, G. Rong^1,47, Ch. Rosner¹⁵, M. Rump⁵¹, A. Sarantsev^27,e, M. Savrié^24b, C. Schnier⁴, K. Schoenning⁵⁷, W. Shan¹⁹, X. Y. Shan^53,43, M. Shao^53,43, C. P. Shen², P. X. Shen³⁴, X. Y. Shen^1,47, H. Y. Sheng¹, X. Shi^1,43, J. J. Song³⁷, W. M. Song³⁷, X. Y. Song¹, S. Sosio^56a,56c, C. Sowa⁴, S. Spataro^56a,56c, G. X. Sun¹, J. F. Sun¹⁶, L. Sun⁵⁸, S. S. Sun^1,47, X. H. Sun¹, Y. J. Sun^53,43, Y. K. Sun^53,43, Y. Z. Sun¹, Z. J. Sun^1,43, Z. T. Sun²², Y. T. Tan^53,43, C. J. Tang⁴⁰, G. Y. Tang¹, X. Tang¹, I. Tapan^46c, M. Tiemens²⁹, B. Tsednee²⁵, I. Uman^46d, G. S. Varner⁴⁸, B. Wang¹, B. L. Wang⁴⁷, C. W. Wang³³, D. Y. Wang³⁵, Dan Wang⁴⁷, K. Wang^1,43, L. L. Wang¹, L. S. Wang¹, M. Wang³⁷, Meng Wang^1,47, P. Wang¹, P. L. Wang¹, W. P. Wang^53,43, X. F. Wang¹, Y. Wang^53,43, Y. F. Wang^1,43,47, Y. Q. Wang²⁶, Z. Wang^1,43, Z. G. Wang^1,43, Z. Y. Wang¹, Zongyuan Wang^1,47, T. Weber⁴, D. H. Wei¹², P. Weidenkaff²⁶, S. P. Wen¹, U. Wiedner⁴, M. Wolke⁵⁷, L. H. Wu¹, L. J. Wu^1,47, Z. Wu^1,43, L. Xia^53,43, X. Xia³⁷, Y. Xia²⁰, D. Xiao¹, Y. J. Xiao^1,47, Z. J. Xiao³², Y. G. Xie^1,43, Y. H. Xie⁶, X. A. Xiong^1,47, Q. L. Xiu^1,43, G. F. Xu¹, J. J. Xu^1,47, L. Xu¹, Q. J. Xu¹⁴, Q. N. Xu⁴⁷, X. P. Xu⁴¹, F. Yan⁵⁴, L. Yan^56a,56c, W. B. Yan^53,43, W. C. Yan², Y. H. Yan²⁰, H. J. Yang^38,h, H. X. Yang¹, L. Yang⁵⁸, S. L. Yang^1,47, Y. H. Yang³³, Y. X. Yang¹², Yifan Yang^1,47, Z. Q. Yang²⁰, M. Ye^1,43, M. H. Ye⁷, J. H. Yin¹, Z. Y. You⁴⁴, B. X. Yu^1,43,47, C. X. Yu³⁴, J. S. Yu²⁰, C. Z. Yuan^1,47, Y. Yuan¹, A. Yuncu^46b,a, A. A. Zafar⁵⁵, A. Zallo^23a, Y. Zeng²⁰, Z. Zeng^53,43, B. X. Zhang¹, B. Y. Zhang^1,43, C. C. Zhang¹, D. H. Zhang¹, H. H. Zhang⁴⁴, H. Y. Zhang^1,43, J. Zhang^1,47, J. L. Zhang⁵⁹, J. Q. Zhang⁴, J. W. Zhang^1,43,47, J. Y. Zhang¹, J. Z. Zhang^1,47, K. Zhang^1,47, L. Zhang⁴⁵, S. F. Zhang³³, T. J. Zhang^38,h, X. Y. Zhang³⁷, Y. Zhang^53,43, Y. H. Zhang^1,43, Y. T. Zhang^53,43, Yang Zhang¹, Yao Zhang¹, Yu Zhang⁴⁷, Z. H. Zhang⁶, Z. P. Zhang⁵³, Z. Y. Zhang⁵⁸, G. Zhao¹, J. W. Zhao^1,43, J. Y. Zhao^1,47, J. Z. Zhao^1,43, Lei Zhao^53,43, Ling Zhao¹, M. G. Zhao³⁴, Q. Zhao¹, S. J. Zhao⁶¹, T. C. Zhao¹, Y. B. Zhao^1,43, Z. G. Zhao^53,43, A. Zhemchugov^27,b, B. Zheng⁵⁴, J. P. Zheng^1,43, W. J. Zheng³⁷, Y. H. Zheng⁴⁷, B. Zhong³², L. Zhou^1,43, Q. Zhou^1,47, X. Zhou⁵⁸, X. K. Zhou^53,43, X. R. Zhou^53,43, X. Y. Zhou¹, Xiaoyu Zhou²⁰, Xu Zhou²⁰, A. N. Zhu^1,47, J. Zhu³⁴, J. Zhu⁴⁴, K. Zhu¹, K. J. Zhu^1,43,47, S. Zhu¹, S. H. Zhu⁵², X. L. Zhu⁴⁵, Y. C. Zhu^53,43, Y. S. Zhu^1,47, Z. A. Zhu^1,47, J. Zhuang^1,43, B. S. Zou¹, and J. H. Zou¹ (BESIII Collaboration)

¹Institute of High Energy Physics, Beijing 100049, People’s Republic of China
²Beihang University, Beijing 100191, People’s Republic of China
³Beijing Institute of Petrochemical Technology, Beijing 102617, People’s Republic of China
⁴Bochum Ruhr-University, D-44780 Bochum, Germany
⁵Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA
⁶Central China Normal University, Wuhan 430079, People’s Republic of China
⁷China Center of Advanced Science and Technology, Beijing 100190, People’s Republic of China
⁸COMSATS University Islamabad, Lahore Campus, Defence Road, Off Raiwind Road, 54000 Lahore, Pakistan
⁹Fudan University, Shanghai 200443, People’s Republic of China
¹⁰G.I. Budker Institute of Nuclear Physics SB RAS (BINP), Novosibirsk 630090, Russia
¹¹GSI Helmholtzcentre for Heavy Ion Research GmbH, D-64291 Darmstadt, Germany
¹²Guangxi Normal University, Guilin 541004, People’s Republic of China
¹³Guangxi University, Nanning 530004, People’s Republic of China
¹⁴Hangzhou Normal University, Hangzhou 310036, People’s Republic of China
¹⁵Helmholtz Institute Mainz, Johann-Joachim-Becher-Weg 45, D-55099 Mainz, Germany
¹⁶Henan Normal University, Xinxiang 453007, People’s Republic of China
¹⁷Henan University of Science and Technology, Luoyang 471003, People’s Republic of China
¹⁸Huangshan College, Huangshan 245000, People’s Republic of China
¹⁹Hunan Normal University, Changsha 410081, People’s Republic of China
²⁰Hunan University, Changsha 410082, People’s Republic of China
²¹Indian Institute of Technology Madras, Chennai 600036, India
²²Indiana University, Bloomington, Indiana 47405, USA
^23aINFN Laboratori Nazionali di Frascati, I-00044 Frascati, Italy
^23bINFN and University of Perugia, I-06100 Perugia, Italy
^24aINFN Sezione di Ferrara, I-44122 Ferrara, Italy
^24bUniversity of Ferrara, I-44122 Ferrara, Italy
²⁵Institute of Physics and Technology, Peace Ave. 54B, Ulaanbaatar 13330, Mongolia
²⁶Johannes Gutenberg University of Mainz, Johann-Joachim-Becher-Weg 45, D-55099 Mainz, Germany
²⁷Joint Institute for Nuclear Research, 141980 Dubna, Moscow region, Russia
²⁸Justus-Liebig-Universitaet Giessen, II. Physikalisches Institut, Heinrich-Buff-Ring 16, D-35392 Giessen, Germany
²⁹KVI-CART, University of Groningen, NL-9747 AA Groningen, Netherlands
³⁰Lanzhou University, Lanzhou 730000, People’s Republic of China
³¹Liaoning University, Shenyang 110036, People’s Republic of China
³²Nanjing Normal University, Nanjing 210023, People’s Republic of China
³³Nanjing University, Nanjing 210093, People’s Republic of China
³⁴Nankai University, Tianjin 300071, People’s Republic of China
³⁵Peking University, Beijing 100871, People’s Republic of China
³⁶Seoul National University, Seoul 151-747, Korea
³⁷Shandong University, Jinan 250100, People’s Republic of China
³⁸Shanghai Jiao Tong University, Shanghai 200240, People’s Republic of China
³⁹Shanxi University, Taiyuan 030006, People’s Republic of China
⁴⁰Sichuan University, Chengdu 610064, People’s Republic of China
⁴¹Soochow University, Suzhou 215006, People’s Republic of China
⁴²Southeast University, Nanjing 211100, People’s Republic of China
⁴³State Key Laboratory of Particle Detection and Electronics, Beijing 100049, Hefei 230026, People’s Republic of China
⁴⁴Sun Yat-Sen University, Guangzhou 510275, People’s Republic of China
⁴⁵Tsinghua University, Beijing 100084, People’s Republic of China
^46aAnkara University, 06100 Tandogan, Ankara, Turkey
^46bIstanbul Bilgi University, 34060 Eyup, Istanbul, Turkey
^46cUludag University, 16059 Bursa, Turkey
^46dNear East University, Nicosia, North Cyprus, Mersin 10, Turkey
⁴⁷University of Chinese Academy of Sciences, Beijing 100049, People’s Republic of China
⁴⁸University of Hawaii, Honolulu, Hawaii 96822, USA
⁴⁹University of Jinan, Jinan 250022, People’s Republic of China
⁵⁰University of Minnesota, Minneapolis, Minnesota 55455, USA
⁵¹University of Muenster, Wilhelm-Klemm-Str. 9, 48149 Muenster, Germany
⁵²University of Science and Technology Liaoning, Anshan 114051, People’s Republic of China
⁵³University of Science and Technology of China, Hefei 230026, People’s Republic of China
⁵⁴University of South China, Hengyang 421001, People’s Republic of China
⁵⁵University of the Punjab, Lahore-54590, Pakistan
^56aUniversity of Turin, I-10125 Turin, Italy
^56bUniversity of Eastern Piedmont, I-15121 Alessandria, Italy
^56cINFN, I-10125 Turin, Italy
⁵⁷Uppsala University, Box 516, SE-75120 Uppsala, Sweden
⁵⁸Wuhan University, Wuhan 430072, People’s Republic of China
⁵⁹Xinyang Normal University, Xinyang 464000, People’s Republic of China
⁶⁰Zhejiang University, Hangzhou 310027, People’s Republic of China
⁶¹Zhengzhou University, Zhengzhou 450001, People’s Republic of China

^aAlso at Bogazici University, 34342 Istanbul, Turkey.
^bAlso at the Moscow Institute of Physics and Technology, Moscow 141700, Russia.
^cAlso at the Functional Electronics Laboratory, Tomsk State University, Tomsk 634050, Russia.
^dAlso at the Novosibirsk State University, Novosibirsk 630090, Russia.
^eAlso at the NRC "Kurchatov Institute", PNPI, Gatchina 188300, Russia.
^fAlso at Istanbul Arel University, 34295 Istanbul, Turkey.
^gAlso at Goethe University Frankfurt, 60323 Frankfurt am Main, Germany.
^hAlso at Key Laboratory for Particle Physics, Astrophysics and Cosmology, Ministry of Education; Shanghai Key Laboratory for Particle Physics and Cosmology; Institute of Nuclear and Particle Physics, Shanghai 200240, People’s Republic of China.
ⁱAlso at Government College Women University, Sialkot—51310, Punjab, Pakistan.
^jAlso at Key Laboratory of Nuclear Physics and Ion-beam Application (MOE) and Institute of Modern Physics, Fudan University, Shanghai 200443, People’s Republic of China.
^kCurrently at: Center for Underground Physics, Institute for Basic Science, Daejeon 34126, Korea.
^lAlso at Harvard University, Department of Physics, Cambridge, Massachusetts 02138, USA.

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Phys. Rev. D 99, 091101(R) – Published 13 May, 2019

DOI: https://doi.org/10.1103/PhysRevD.99.091101

Abstract

We report the observation of $W$ -annihilation decay $D_{s}^{+} \to ω π^{+}$ and evidence for $D_{s}^{+} \to ω K^{+}$ in a data sample corresponding to an integrated luminosity of $3.19 {fb}^{- 1}$ collected with the BESIII detector at a center-of-mass energy $\sqrt{s} = 4.178 GeV$ . We obtain the branching fractions $B (D_{s}^{+} \to ω π^{+}) = (1.77 \pm 0.3 2_{stat} \pm 0.1 3_{sys}) \times 10^{- 3}$ with a significance of $6.7 σ$ and $B (D_{s}^{+} \to ω K^{+}) = (0.87 \pm 0.2 4_{stat} \pm 0.0 8_{sys}) \times 10^{- 3}$ with a significance of $4.4 σ$ . This measurement provides critical information to determine the nonperturbative $W$ -annihilation amplitudes and shows the potential of searching for $C P$ asymmetry in $D_{s}^{+} \to ω K^{+}$ .

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Throughout this paper, for resolutions determined by 1D fits and control samples, the given uncertainties are used to estimate the systematic uncertainties due to signal description. For the masses and widthes of particles, which fixed at PDG values. The uncertainties from PDG are used to estimate the systematic uncertainties due to signal description.

Phys. Rev. D 99, 091101(R)– Published 13 May, 2019

Vol. 99, Iss. 9 — 1 May 2019

Received 3 November 2018

DOI: https://doi.org/10.1103/PhysRevD.99.091101

Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. Funded by SCOAP³.

Published by the American Physical Society

Physical Review D

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Observation of the $W$ -annihilation decay $D_{s}^{+} \to ω π^{+}$ and evidence for $D_{s}^{+} \to ω K^{+}$

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Observation of the W-annihilation decay Ds+→ωπ+ and evidence for Ds+→ωK+

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Observation of the $W$ -annihilation decay $D_{s}^{+} \to ω π^{+}$ and evidence for $D_{s}^{+} \to ω K^{+}$