The study of $\gamma\gamma\to\gamma\psi(2S)$ at Belle
Popis: | Using $980~\rm fb^{-1}$ of data on and around the $\Upsilon(nS)(n=1,2,3,4,5)$ resonances collected with the Belle detector at the KEKB asymmetric-energy $e^+e^-$ collider, the two-photon process $\gamma\gamma\to \gamma\psi(2S)$ is studied from $\sqrt{s} = 3.7$ to $4.2~{\rm GeV}$ for the first time. Evidence is found for a structure in the invariant mass distribution of $\gamma\psi(2S)$ at $M_1 = 3921.3\pm 2.4 \pm 1.6~{\rm MeV}/c^2$ with a width of $\Gamma_1 = 0.0\pm 5.3 \pm 2.0~{\rm MeV}$ and a significance of $4.0\sigma$ including systematic uncertainties, and another structure is seen at $M_2 = 4014.4\pm 4.1 \pm 0.5~{\rm MeV}/c^2$ with a width of $\Gamma_2 = 6\pm 16 \pm 6~{\rm MeV}$ and a global significance of $2.8\sigma$ including the look-elsewhere effect, if the mass spectrum is parametrized with the incoherent sum of two Breit-Wigner functions. The upper limits of the widths are determined to be $\Gamma_1^{\rm UL} = 11.5~{\rm MeV}$ and $\Gamma_2^{\rm UL} = 39.3~{\rm MeV}$ at 90% confidence level. The production rates are determined to be $\Gamma_{\gamma\gamma}{\cal B}(R_1\to\gamma\psi(2S)) = 8.2\pm 2.3\pm 0.9~{\rm eV}$ assuming $(J^{PC}, |\lambda|) =(0^{++}, 0)$ and $1.6\pm 0.5\pm 0.2~{\rm eV}$ with $(2^{++}, 2)$ for the first structure and $\Gamma_{\gamma\gamma}{\cal B}(R_2\to\gamma\psi(2S)) = 5.3\pm 2.7\pm 2.5~{\rm eV}$ with $(0^{++}, 0)$ and $1.1\pm 0.5\pm 0.5~{\rm eV}$ with $(2^{++}, 2)$ for the second one. Here, the first errors are statistical and the second systematic. |
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Jazyk: | English |
DOI: | 10.3204/pubdb-2021-04438 |
Přístupová URL adresa: | https://explore.openaire.eu/search/publication?articleId=doi_________::216e45e37187b27a957ff8e49776834b |
Přírůstkové číslo: | edsair.doi...........216e45e37187b27a957ff8e49776834b |
Autor: | Wang, X. L., Gao, B. S., Zhu, W. J., Adachi, I., Aihara, H., Al Said, S., Asner, D. M., Atmacan, H., Aulchenko, V., Aushev, T., Ayad, R., Babu, Varghese, Bahinipati, S., Behera, P., Bhardwaj, V., Bhuyan, B., Bilka, T., Biswal, J., Bobrov, A., Bonvicini, G., Bozek, A., Bra��ko, M., Campajola, M., ��ervenkov, D., Chang, M.-C., Chekelian, V., Chen, A., Cheon, B. G., Chilikin, K., Cho, H. E., Cho, K., Choi, S.-K., Choi, Y., Choudhury, S., Cinabro, D., Cunliffe, S., Das, S., De Nardo, G., Dhamija, R., Di Capua, F., Dole��al, Z., Dong, T. V., Eidelman, S., Ferber, T., Ferlewicz, D., Frey, A., Fulsom, B. G., Garg, R., Gaur, V., Gabyshev, N., Garmash, A., Giri, A., Goldenzweig, P., Golob, B., Hadjivasiliou, C., Hara, T., Hartbrich, O., Hayasaka, K., Hayashii, H., Hedges, M. T., Hou, W.-S., Hsu, C.-L., Iijima, T., Inami, K., Ishikawa, A., Itoh, R., Iwasaki, M., Iwasaki, Y., Jacobs, W. W., Jia, S., Jin, Y., Joo, C. W., Joo, K. K., Kahn, J., Kang, K. H., Kawasaki, T., Kiesling, C., Kim, C. H., Kim, D. Y., Kim, S. H., Kim, Y.-K., Kody��, P., Konno, T., Korobov, A., Korpar, S., Kovalenko, E., Kri��an, P., Kroeger, R., Krokovny, P., Kulasiri, R., Kumar, M., Kumar, R., Kumara, K., Kuzmin, A., Kwon, Y.-J., Lalwani, K., Lange, J. S., Lee, I. S., Lee, S. C., Lewis, P., Li, J., Li, L. K., Li, Y. B., Li Gioi, L., Libby, J., Lieret, K., Liventsev, D., MacQueen, C., Masuda, M., Matsuda, T., Matvienko, D., Merola, M., Metzner, F., Miyabayashi, K., Mizuk, R., Mohanty, G. B., Mrvar, M., Mussa, R., Nakao, M., Natkaniec, Z., Natochii, A., Nayak, L., Nayak, M., Niiyama, M., Nisar, N. K., Nishida, S., Nishimura, K., Ogawa, S., Ono, H., Onuki, Y., Oskin, P., Pakhlov, P., Pakhlova, G., Pang, T., Pardi, S., Park, H., Park, S.-H., Patra, S., Paul, S., Pedlar, T. K., Pestotnik, R., Piilonen, L. E., Podobnik, T., Popov, V., Prencipe, E., Prim, M. T., Roehrken, Markus, Rostomyan, A., Rout, N., Russo, G., Sahoo, D., Sandilya, S., Sangal, A., Santelj, L., Sanuki, T., Schnell, G., Schwanda, C., Seino, Y., Senyo, K., Sevior, M. E., Shapkin, M., Sharma, C., Shen, C. P., Shiu, J.-G., Shwartz, B., Simon, F., Singh, J. B., Sokolov, A., Solovieva, E., Stani��, S., Stari��, M., Stottler, Z. S., Sumihama, M., Takizawa, M., Tamponi, U., Tenchini, Francesco, Uchida, M., Uehara, S., Uglov, T., Unno, Y., Uno, S., Urquijo, P., Usov, Y., Van Tonder, R., Varner, G., Vossen, A., Waheed, E., Wang, C. H., Wang, M.-Z., Wang, P., Watanabe, M., Watanuki, S., Werbycka, O., Won, E., Xu, X., Yan, W., Yang, S. B., Ye, Hua, Yin, J. H., Yuan, C. Z., Zhang, Z. P., Zhilich, V., Zhukova, V. |
Jazyk: | angličtina |
Rok vydání: | 2021 |
Předmět: |
exchange: two-photon
data analysis method 3.7-4.2 GeV-cms width: branching ratio BELLE electron positron: colliding beams electron positron: annihilation Breit-Wigner error: statistical mass: width KEK-B photon photon --> photon psi(3685) width: upper limit structure mass spectrum: (photon psi(3685)) psi(3685) experimental results |
DOI: | 10.3204/pubdb-2021-04438 |
Popis: | Using $980~\rm fb^{-1}$ of data on and around the $\Upsilon(nS)(n=1,2,3,4,5)$ resonances collected with the Belle detector at the KEKB asymmetric-energy $e^+e^-$ collider, the two-photon process $\gamma\gamma\to \gamma\psi(2S)$ is studied from $\sqrt{s} = 3.7$ to $4.2~{\rm GeV}$ for the first time. Evidence is found for a structure in the invariant mass distribution of $\gamma\psi(2S)$ at $M_1 = 3921.3\pm 2.4 \pm 1.6~{\rm MeV}/c^2$ with a width of $\Gamma_1 = 0.0\pm 5.3 \pm 2.0~{\rm MeV}$ and a significance of $4.0\sigma$ including systematic uncertainties, and another structure is seen at $M_2 = 4014.4\pm 4.1 \pm 0.5~{\rm MeV}/c^2$ with a width of $\Gamma_2 = 6\pm 16 \pm 6~{\rm MeV}$ and a global significance of $2.8\sigma$ including the look-elsewhere effect, if the mass spectrum is parametrized with the incoherent sum of two Breit-Wigner functions. The upper limits of the widths are determined to be $\Gamma_1^{\rm UL} = 11.5~{\rm MeV}$ and $\Gamma_2^{\rm UL} = 39.3~{\rm MeV}$ at 90% confidence level. The production rates are determined to be $\Gamma_{\gamma\gamma}{\cal B}(R_1\to\gamma\psi(2S)) = 8.2\pm 2.3\pm 0.9~{\rm eV}$ assuming $(J^{PC}, |\lambda|) =(0^{++}, 0)$ and $1.6\pm 0.5\pm 0.2~{\rm eV}$ with $(2^{++}, 2)$ for the first structure and $\Gamma_{\gamma\gamma}{\cal B}(R_2\to\gamma\psi(2S)) = 5.3\pm 2.7\pm 2.5~{\rm eV}$ with $(0^{++}, 0)$ and $1.1\pm 0.5\pm 0.5~{\rm eV}$ with $(2^{++}, 2)$ for the second one. Here, the first errors are statistical and the second systematic. |
Databáze: | OpenAIRE |
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