1. Measurement of branching fractions and search for CP violation in D 0 → π + π − η, D 0 → K + K − η, and D 0 → ϕη at Belle
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S. Sandilya, S. Jia, G.V. Russo, A. Kuzmin, A. Korobov, S. Al Said, A. Sangal, E.-J. Jang, W. S. Hou, M. Starič, M. Merola, G. Bonvicini, A. Vinokurova, S. E. Vahsen, K. Senyo, E. Graziani, P. Krokovny, Y. Choi, V. Popov, Yongsun Kim, K. Lalwani, V.N. Zhilich, M. Takizawa, K. H. Kang, K. Cho, S. Uno, C. Schwanda, Y. Iwasaki, John Yelton, G. Schnell, Z. Doležal, G. De Nardo, Y. J. Kwon, W. B. Yan, D. Epifanov, Z. Natkaniec, M. Iwasaki, S. Das, G. De Pietro, L. Nayak, V. Babu, M. Z. Wang, K. Kinoshita, K. Miyabayashi, N. Rout, T. Kuhr, E. Won, V. Gaur, T. K. Pedlar, Antonio Budano, B. G. Cheon, G. B. Mohanty, B. Golob, C. H. Li, T. Gu, L. K. Li, M. Nayak, Y. Yusa, Dipak Kumar Sahoo, F. Tenchini, F. Di Capua, Luka Santelj, S. K. Choi, Seongbae Yang, R. Ayad, T. Ferber, T. Uglov, A. K. Giri, Seema Bahinipati, Prafulla Kumar Behera, Y. Sakai, Shih-Chang Lee, P. Pakhlov, A. Natochii, T. Sumiyoshi, K. Inami, K. Lieret, A. Passeri, K.-H. Kim, J. Biswal, M. Bračko, H. E. Cho, N. K. Nisar, M. Masuda, K. Uno, Felix Metzner, M. Uchida, C. H. Kim, T. Sanuki, Tomoyuki Konno, D. Y. Kim, S.-H. Park, A. Bozek, J. Bennett, E. Prencipe, H. Atmacan, K. K. Joo, L. E. Piilonen, G. S. Varner, P. Oskin, J. G. Shiu, T. V. Dong, S.-J. Cho, A. Chen, N. Dash, C. P. Shen, E. Solovieva, L. Li Gioi, Iki Adachi, Seok Kim, B. G. Fulsom, M. Shapkin, A. J. Schwartz, K. Chilikin, K. Nishimura, M. Laurenza, A. Bobrov, R. Mizuk, M. Campajola, V. Savinov, S. Nishida, S. Cunliffe, M. Sumihama, X. L. Wang, M. C. Chang, V. Chekelian, H. Ono, R. Dhamija, R. Van Tonder, Tagir Aushev, E. Waheed, Samo Korpar, V. Zhukova, C. Sharma, Peter Kodys, W. W. Jacobs, P. L. Wang, V.M. Aulchenko, Y. Unno, Y. Guan, P. Branchini, K. Kumara, G. Karyan, T. Mori, H. Aihara, Z. S. Stottler, S. Watanuki, Z. P. Zhang, G. Pakhlova, H. Ye, M. Niiyama, S. Halder, T. Bilka, T. E. Browder, M. Bessner, C. H. Wang, S. Paul, S. Pardi, B.A. Shwartz, Y. Q. Chen, Bruce Yabsley, Y. Jin, R. Kroeger, P. Goldenzweig, R. Pestotnik, K. Tanida, D. Cinabro, P. Chang, M. Kumar, D. Červenkov, Somnath Choudhury, D. Matvienko, J. Libby, D. M. Asner, J. H. Yin, K. Hayasaka, C. Kiesling, E. Kovalenko, Rocky Bala Garg, Y. Seino, C. Hadjivasiliou, M. T. Prim, D. Liventsev, A. Ishikawa, M. Nakao, P. Križan, Andrey Sokolov, T. Podobnik, Semen Eidelman, Belle, Collaboration, Campajola, M., De Nardo, G., Di Capua, F., Merola, M., Pardi, S., Russo, G., and Et, Al.
- Subjects
Physics ,Nuclear and High Energy Physics ,Charm physic ,010308 nuclear & particles physics ,Branching fraction ,e ,− ,e +-e − Experiments ,QC770-798 ,+ ,01 natural sciences ,Combinatorics ,KEKB ,CP violation ,Nuclear and particle physics. Atomic energy. Radioactivity ,0103 physical sciences ,010306 general physics ,Experiments ,Charm physics - Abstract
We measure the branching fractions and CP asymmetries for the singly Cabibbo-suppressed decays D0 → π+π−η, D0 → K+K−η, and D0 → ϕη, using 980 fb−1 of data from the Belle experiment at the KEKB e+e− collider. We obtain$$ {\displaystyle \begin{array}{c}\mathcal{B}\left({D}^0\to {\pi}^{+}{\pi}^{-}\eta \right)=\left[1.22\pm 0.02\left(\mathrm{stat}\right)\pm 0.02\left(\mathrm{syst}\right)\pm 0.03\left({\mathcal{B}}_{\mathrm{ref}}\right)\right]\times {10}^{-3},\\ {}\mathcal{B}\left({D}^0\to {K}^{+}{K}^{-}\eta \right)=\left[{1.80}_{-0.06}^{+0.07}\left(\mathrm{stat}\right)\pm 0.04\left(\mathrm{syst}\right)\pm 0.05\left({\mathcal{B}}_{\mathrm{ref}}\right)\right]\times {10}^{-4},\\ {}\mathcal{B}\left({D}^0\to \phi \eta \right)=\left[1.84\pm 0.09\left(\mathrm{stat}\right)\pm 0.06\left(\mathrm{syst}\right)\pm 0.05\left({\mathcal{B}}_{\mathrm{ref}}\right)\right]\times {10}^{-4},\end{array}} $$ B D 0 → π + π − η = 1.22 ± 0.02 stat ± 0.02 syst ± 0.03 B ref × 10 − 3 , B D 0 → K + K − η = 1.80 − 0.06 + 0.07 stat ± 0.04 syst ± 0.05 B ref × 10 − 4 , B D 0 → ϕη = 1.84 ± 0.09 stat ± 0.06 syst ± 0.05 B ref × 10 − 4 , where the third uncertainty ($$ \mathcal{B} $$ B ref) is from the uncertainty in the branching fraction of the reference mode D0 → K−π+η. The color-suppressed decay D0 → ϕη is observed for the first time, with very high significance. The results for the CP asymmetries are$$ {\displaystyle \begin{array}{c}{A}_{CP}\left({D}^0\ {\pi}^{+}{\pi}^{-}\eta \right)=\left[0.9\pm 1.2\left(\mathrm{stat}\right)\pm 0.5\left(\mathrm{syst}\right)\right]\%,\\ {}{A}_{CP}\left({D}^0\to {K}^{+}{K}^{-}\eta \right)=\left[-1.4\pm 3.3\left(\mathrm{stat}\right)\pm 1.1\left(\mathrm{syst}\right)\right]\%,\\ {} ACP\ \left({D}^0\to \phi \eta \right)=\left[-1.9\pm 4.4\left(\mathrm{stat}\right)\pm 0.6\left(\mathrm{syst}\right)\right]\%.\end{array}} $$ A CP D 0 π + π − η = 0.9 ± 1.2 stat ± 0.5 syst % , A CP D 0 → K + K − η = − 1.4 ± 3.3 stat ± 1.1 syst % , ACP D 0 → ϕη = − 1.9 ± 4.4 stat ± 0.6 syst % . The results for D0 → π+π−η are a significant improvement over previous results. The branching fraction and ACP results for D0 → K+K−η, and the ACP result for D0 → ϕη, are the first such measurements. No evidence for CP violation is found in any of these decays.
- Published
- 2021