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Title: Observation of τ π ν τ e + e and search for τ π ν τ μ + μ

Abstract

We present the first measurements of branching fractions of rare tau-lepton decays, τ → πντ+ (ℓ = e or μ), using a data sample corresponding to 562 fb–1 collected at a center-of-mass energy of 10.58 GeV with the Belle detector at the KEKB asymmetric-energy e+e collider. The τ → πντe+e decay is observed for the first time with 7.0σ significance. The partial branching fraction determined by the structure-dependent mechanisms mediated by either a vector or an axial-vector current for the mass region Mπee > 1.05 GeV/c2 is measured to be B(τ → πντe+e)[Mπe+e > 1.05 GeV/c2] = (5.90 ± 0.53 ± 0.85 ± 0.11) × 10–6, where the first uncertainty is statistical, the second is systematic, and the third is due to model dependence. In the full phase space, due to the different detection efficiencies for the structure-dependent mechanisms mediated by axial-vector and vector currents, the branching fraction varies from BA → πντe+e) = (1.46 ± 0.13 ± 0.21) × 10–5 to BV → πντe+e) = (3.01 ± 0.27 ± 0.43) × 10–5, respectively. An upper limit is set on the branching fraction of the τ → πντμ+μ decay, B(τ → πντμ+μ) < 1.14 × 10–5, at the 90% confidencemore » level.« less

Authors:
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Publication Date:
Research Org.:
Brookhaven National Lab. (BNL), Upton, NY (United States); Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Virginia Polytechnic Inst. and State Univ. (Virginia Tech), Blacksburg, VA (United States); Univ. of Hawaii, Honolulu, HI (United States)
Sponsoring Org.:
USDOE Office of Science (SC), High Energy Physics (HEP); National Science Foundation (NSF); USDOE Office of Science (SC), Nuclear Physics (NP)
Contributing Org.:
Belle Collaboration
OSTI Identifier:
1570499
Alternate Identifier(s):
OSTI ID: 1572968; OSTI ID: 1577438; OSTI ID: 1593771
Report Number(s):
BNL-212289-2019-JAAM; PNNL-SA-149804
Journal ID: ISSN 2470-0010; PRVDAQ; 071101
Grant/Contract Number:  
SC0012704; AC05-76RL01830; SC0009973; SC0010504
Resource Type:
Published Article
Journal Name:
Physical Review D
Additional Journal Information:
Journal Name: Physical Review D Journal Volume: 100 Journal Issue: 7; Journal ID: ISSN 2470-0010
Publisher:
American Physical Society (APS)
Country of Publication:
United States
Language:
English
Subject:
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS

Citation Formats

Jin, Y., Aihara, H., Epifanov, D., Adachi, I., Al Said, S., Asner, D. M., Aulchenko, V., Aushev, T., Ayad, R., Babu, V., Badhrees, I., Bahinipati, S., Bansal, V., Behera, P., Berger, M., Bhardwaj, V., Bilka, T., Biswal, J., Bobrov, A., Bonvicini, G., Bozek, A., Bračko, M., Campajola, M., Cao, L., Červenkov, D., Chekelian, V., Chen, A., Cheon, B. G., Chilikin, K., Cho, H. E., Cho, K., Choi, Y., Choudhury, S., Cinabro, D., Cunliffe, S., Di Carlo, S., Doležal, Z., Dong, T. V., Dossett, D., Eidelman, S., Fast, J. E., Ferber, T., Fulsom, B. G., Garg, R., Gaur, V., Gabyshev, N., Garmash, A., Giri, A., Goldenzweig, P., Golob, B., Greenwald, D., Grzymkowska, O., Haba, J., Hayasaka, K., Hayashii, H., Hedges, M. T., Hou, W. -S., Huang, K., Iijima, T., Inami, K., Inguglia, G., Ishikawa, A., Iwasaki, M., Iwasaki, Y., Jacobs, W. W., Jeon, H. B., Jia, S., Joffe, D., Joo, K. K., Kahn, J., Kaliyar, A. B., Karyan, G., Kawasaki, T., Kichimi, H., Kiesling, C., Kim, D. Y., Kim, H. J., Kim, K. T., Kim, S. H., Kinoshita, K., Kodyš, P., Korpar, S., Kotchetkov, D., Križan, P., Kroeger, R., Krokovny, P., Kulasiri, R., Kumar, R., Kuzmin, A., Kwon, Y. -J., Lalwani, K., Lange, J. S., Lee, J. Y., Lee, S. C., Li, C. H., Li, L. K., Li, Y. B., Li Gioi, L., Libby, J., Lieret, K., Liptak, Z., Liventsev, D., Lu, P. -C., Luo, T., MacNaughton, J., Masuda, M., Matsuda, T., Matvienko, D., Merola, M., Miyabayashi, K., Miyata, H., Mizuk, R., Mori, T., Mussa, R., Nakano, E., Nakao, M., Nath, K. J., Natkaniec, Z., Nayak, M., Niiyama, M., Nisar, N. K., Nishida, S., Ogawa, S., Ono, H., Onuki, Y., Pakhlov, P., Pakhlova, G., Pal, B., Pardi, S., Park, H., Park, S. -H., Patra, S., Paul, S., Pedlar, T. K., Pestotnik, R., Piilonen, L. E., Popov, V., Prencipe, E., Purohit, M. V., Rostomyan, A., Russo, G., Sahoo, D., Sakai, Y., Salehi, M., Sandilya, S., Santelj, L., Sanuki, T., Savinov, V., Schneider, O., Schnell, G., Schueler, J., Schwanda, C., Seino, Y., Senyo, K., Seon, O., Sevior, M. E., Shebalin, V., Shen, C. P., Shiu, J. -G., Shwartz, B., Simon, F., Singh, J. B., Sokolov, A., Solovieva, E., Stanič, S., Starič, M., Stottler, Z. S., Strube, J. F., Sumiyoshi, T., Takizawa, M., Tamponi, U., Tanida, K., Tenchini, F., Trabelsi, K., Uchida, M., Uglov, T., Unno, Y., Uno, S., Urquijo, P., Usov, Y., Van Tonder, R., Varner, G., Vinokurova, A., Vorobyev, V., Vossen, A., Wang, B., Wang, C. H., Wang, M. -Z., Wang, P., Watanuki, S., Won, E., Yang, S. B., Ye, H., Yin, J. H., Yuan, C. Z., Yusa, Y., Zhang, Z. P., Zhilich, V., Zhukova, V., and Belle Collaboration. Observation of τ–→π–ντe+e– and search for τ–→π–ντμ+μ–. United States: N. p., 2019. Web. doi:10.1103/PhysRevD.100.071101.
Jin, Y., Aihara, H., Epifanov, D., Adachi, I., Al Said, S., Asner, D. M., Aulchenko, V., Aushev, T., Ayad, R., Babu, V., Badhrees, I., Bahinipati, S., Bansal, V., Behera, P., Berger, M., Bhardwaj, V., Bilka, T., Biswal, J., Bobrov, A., Bonvicini, G., Bozek, A., Bračko, M., Campajola, M., Cao, L., Červenkov, D., Chekelian, V., Chen, A., Cheon, B. G., Chilikin, K., Cho, H. E., Cho, K., Choi, Y., Choudhury, S., Cinabro, D., Cunliffe, S., Di Carlo, S., Doležal, Z., Dong, T. V., Dossett, D., Eidelman, S., Fast, J. E., Ferber, T., Fulsom, B. G., Garg, R., Gaur, V., Gabyshev, N., Garmash, A., Giri, A., Goldenzweig, P., Golob, B., Greenwald, D., Grzymkowska, O., Haba, J., Hayasaka, K., Hayashii, H., Hedges, M. T., Hou, W. -S., Huang, K., Iijima, T., Inami, K., Inguglia, G., Ishikawa, A., Iwasaki, M., Iwasaki, Y., Jacobs, W. W., Jeon, H. B., Jia, S., Joffe, D., Joo, K. K., Kahn, J., Kaliyar, A. B., Karyan, G., Kawasaki, T., Kichimi, H., Kiesling, C., Kim, D. Y., Kim, H. J., Kim, K. T., Kim, S. H., Kinoshita, K., Kodyš, P., Korpar, S., Kotchetkov, D., Križan, P., Kroeger, R., Krokovny, P., Kulasiri, R., Kumar, R., Kuzmin, A., Kwon, Y. -J., Lalwani, K., Lange, J. S., Lee, J. Y., Lee, S. C., Li, C. H., Li, L. K., Li, Y. B., Li Gioi, L., Libby, J., Lieret, K., Liptak, Z., Liventsev, D., Lu, P. -C., Luo, T., MacNaughton, J., Masuda, M., Matsuda, T., Matvienko, D., Merola, M., Miyabayashi, K., Miyata, H., Mizuk, R., Mori, T., Mussa, R., Nakano, E., Nakao, M., Nath, K. J., Natkaniec, Z., Nayak, M., Niiyama, M., Nisar, N. K., Nishida, S., Ogawa, S., Ono, H., Onuki, Y., Pakhlov, P., Pakhlova, G., Pal, B., Pardi, S., Park, H., Park, S. -H., Patra, S., Paul, S., Pedlar, T. K., Pestotnik, R., Piilonen, L. E., Popov, V., Prencipe, E., Purohit, M. V., Rostomyan, A., Russo, G., Sahoo, D., Sakai, Y., Salehi, M., Sandilya, S., Santelj, L., Sanuki, T., Savinov, V., Schneider, O., Schnell, G., Schueler, J., Schwanda, C., Seino, Y., Senyo, K., Seon, O., Sevior, M. E., Shebalin, V., Shen, C. P., Shiu, J. -G., Shwartz, B., Simon, F., Singh, J. B., Sokolov, A., Solovieva, E., Stanič, S., Starič, M., Stottler, Z. S., Strube, J. F., Sumiyoshi, T., Takizawa, M., Tamponi, U., Tanida, K., Tenchini, F., Trabelsi, K., Uchida, M., Uglov, T., Unno, Y., Uno, S., Urquijo, P., Usov, Y., Van Tonder, R., Varner, G., Vinokurova, A., Vorobyev, V., Vossen, A., Wang, B., Wang, C. H., Wang, M. -Z., Wang, P., Watanuki, S., Won, E., Yang, S. B., Ye, H., Yin, J. H., Yuan, C. Z., Yusa, Y., Zhang, Z. P., Zhilich, V., Zhukova, V., & Belle Collaboration. Observation of τ–→π–ντe+e– and search for τ–→π–ντμ+μ–. United States. doi:https://doi.org/10.1103/PhysRevD.100.071101
Jin, Y., Aihara, H., Epifanov, D., Adachi, I., Al Said, S., Asner, D. M., Aulchenko, V., Aushev, T., Ayad, R., Babu, V., Badhrees, I., Bahinipati, S., Bansal, V., Behera, P., Berger, M., Bhardwaj, V., Bilka, T., Biswal, J., Bobrov, A., Bonvicini, G., Bozek, A., Bračko, M., Campajola, M., Cao, L., Červenkov, D., Chekelian, V., Chen, A., Cheon, B. G., Chilikin, K., Cho, H. E., Cho, K., Choi, Y., Choudhury, S., Cinabro, D., Cunliffe, S., Di Carlo, S., Doležal, Z., Dong, T. V., Dossett, D., Eidelman, S., Fast, J. E., Ferber, T., Fulsom, B. G., Garg, R., Gaur, V., Gabyshev, N., Garmash, A., Giri, A., Goldenzweig, P., Golob, B., Greenwald, D., Grzymkowska, O., Haba, J., Hayasaka, K., Hayashii, H., Hedges, M. T., Hou, W. -S., Huang, K., Iijima, T., Inami, K., Inguglia, G., Ishikawa, A., Iwasaki, M., Iwasaki, Y., Jacobs, W. W., Jeon, H. B., Jia, S., Joffe, D., Joo, K. K., Kahn, J., Kaliyar, A. B., Karyan, G., Kawasaki, T., Kichimi, H., Kiesling, C., Kim, D. Y., Kim, H. J., Kim, K. T., Kim, S. H., Kinoshita, K., Kodyš, P., Korpar, S., Kotchetkov, D., Križan, P., Kroeger, R., Krokovny, P., Kulasiri, R., Kumar, R., Kuzmin, A., Kwon, Y. -J., Lalwani, K., Lange, J. S., Lee, J. Y., Lee, S. C., Li, C. H., Li, L. K., Li, Y. B., Li Gioi, L., Libby, J., Lieret, K., Liptak, Z., Liventsev, D., Lu, P. -C., Luo, T., MacNaughton, J., Masuda, M., Matsuda, T., Matvienko, D., Merola, M., Miyabayashi, K., Miyata, H., Mizuk, R., Mori, T., Mussa, R., Nakano, E., Nakao, M., Nath, K. J., Natkaniec, Z., Nayak, M., Niiyama, M., Nisar, N. K., Nishida, S., Ogawa, S., Ono, H., Onuki, Y., Pakhlov, P., Pakhlova, G., Pal, B., Pardi, S., Park, H., Park, S. -H., Patra, S., Paul, S., Pedlar, T. K., Pestotnik, R., Piilonen, L. E., Popov, V., Prencipe, E., Purohit, M. V., Rostomyan, A., Russo, G., Sahoo, D., Sakai, Y., Salehi, M., Sandilya, S., Santelj, L., Sanuki, T., Savinov, V., Schneider, O., Schnell, G., Schueler, J., Schwanda, C., Seino, Y., Senyo, K., Seon, O., Sevior, M. E., Shebalin, V., Shen, C. P., Shiu, J. -G., Shwartz, B., Simon, F., Singh, J. B., Sokolov, A., Solovieva, E., Stanič, S., Starič, M., Stottler, Z. S., Strube, J. F., Sumiyoshi, T., Takizawa, M., Tamponi, U., Tanida, K., Tenchini, F., Trabelsi, K., Uchida, M., Uglov, T., Unno, Y., Uno, S., Urquijo, P., Usov, Y., Van Tonder, R., Varner, G., Vinokurova, A., Vorobyev, V., Vossen, A., Wang, B., Wang, C. H., Wang, M. -Z., Wang, P., Watanuki, S., Won, E., Yang, S. B., Ye, H., Yin, J. H., Yuan, C. Z., Yusa, Y., Zhang, Z. P., Zhilich, V., Zhukova, V., and Belle Collaboration. Tue . "Observation of τ–→π–ντe+e– and search for τ–→π–ντμ+μ–". United States. doi:https://doi.org/10.1103/PhysRevD.100.071101.
@article{osti_1570499,
title = {Observation of τ–→π–ντe+e– and search for τ–→π–ντμ+μ–},
author = {Jin, Y. and Aihara, H. and Epifanov, D. and Adachi, I. and Al Said, S. and Asner, D. M. and Aulchenko, V. and Aushev, T. and Ayad, R. and Babu, V. and Badhrees, I. and Bahinipati, S. and Bansal, V. and Behera, P. and Berger, M. and Bhardwaj, V. and Bilka, T. and Biswal, J. and Bobrov, A. and Bonvicini, G. and Bozek, A. and Bračko, M. and Campajola, M. and Cao, L. and Červenkov, D. and Chekelian, V. and Chen, A. and Cheon, B. G. and Chilikin, K. and Cho, H. E. and Cho, K. and Choi, Y. and Choudhury, S. and Cinabro, D. and Cunliffe, S. and Di Carlo, S. and Doležal, Z. and Dong, T. V. and Dossett, D. and Eidelman, S. and Fast, J. E. and Ferber, T. and Fulsom, B. G. and Garg, R. and Gaur, V. and Gabyshev, N. and Garmash, A. and Giri, A. and Goldenzweig, P. and Golob, B. and Greenwald, D. and Grzymkowska, O. and Haba, J. and Hayasaka, K. and Hayashii, H. and Hedges, M. T. and Hou, W. -S. and Huang, K. and Iijima, T. and Inami, K. and Inguglia, G. and Ishikawa, A. and Iwasaki, M. and Iwasaki, Y. and Jacobs, W. W. and Jeon, H. B. and Jia, S. and Joffe, D. and Joo, K. K. and Kahn, J. and Kaliyar, A. B. and Karyan, G. and Kawasaki, T. and Kichimi, H. and Kiesling, C. and Kim, D. Y. and Kim, H. J. and Kim, K. T. and Kim, S. H. and Kinoshita, K. and Kodyš, P. and Korpar, S. and Kotchetkov, D. and Križan, P. and Kroeger, R. and Krokovny, P. and Kulasiri, R. and Kumar, R. and Kuzmin, A. and Kwon, Y. -J. and Lalwani, K. and Lange, J. S. and Lee, J. Y. and Lee, S. C. and Li, C. H. and Li, L. K. and Li, Y. B. and Li Gioi, L. and Libby, J. and Lieret, K. and Liptak, Z. and Liventsev, D. and Lu, P. -C. and Luo, T. and MacNaughton, J. and Masuda, M. and Matsuda, T. and Matvienko, D. and Merola, M. and Miyabayashi, K. and Miyata, H. and Mizuk, R. and Mori, T. and Mussa, R. and Nakano, E. and Nakao, M. and Nath, K. J. and Natkaniec, Z. and Nayak, M. and Niiyama, M. and Nisar, N. K. and Nishida, S. and Ogawa, S. and Ono, H. and Onuki, Y. and Pakhlov, P. and Pakhlova, G. and Pal, B. and Pardi, S. and Park, H. and Park, S. -H. and Patra, S. and Paul, S. and Pedlar, T. K. and Pestotnik, R. and Piilonen, L. E. and Popov, V. and Prencipe, E. and Purohit, M. V. and Rostomyan, A. and Russo, G. and Sahoo, D. and Sakai, Y. and Salehi, M. and Sandilya, S. and Santelj, L. and Sanuki, T. and Savinov, V. and Schneider, O. and Schnell, G. and Schueler, J. and Schwanda, C. and Seino, Y. and Senyo, K. and Seon, O. and Sevior, M. E. and Shebalin, V. and Shen, C. P. and Shiu, J. -G. and Shwartz, B. and Simon, F. and Singh, J. B. and Sokolov, A. and Solovieva, E. and Stanič, S. and Starič, M. and Stottler, Z. S. and Strube, J. F. and Sumiyoshi, T. and Takizawa, M. and Tamponi, U. and Tanida, K. and Tenchini, F. and Trabelsi, K. and Uchida, M. and Uglov, T. and Unno, Y. and Uno, S. and Urquijo, P. and Usov, Y. and Van Tonder, R. and Varner, G. and Vinokurova, A. and Vorobyev, V. and Vossen, A. and Wang, B. and Wang, C. H. and Wang, M. -Z. and Wang, P. and Watanuki, S. and Won, E. and Yang, S. B. and Ye, H. and Yin, J. H. and Yuan, C. Z. and Yusa, Y. and Zhang, Z. P. and Zhilich, V. and Zhukova, V. and Belle Collaboration},
abstractNote = {We present the first measurements of branching fractions of rare tau-lepton decays, τ– → π–ντℓ+ℓ– (ℓ = e or μ), using a data sample corresponding to 562 fb–1 collected at a center-of-mass energy of 10.58 GeV with the Belle detector at the KEKB asymmetric-energy e+e– collider. The τ– → π–ντe+e– decay is observed for the first time with 7.0σ significance. The partial branching fraction determined by the structure-dependent mechanisms mediated by either a vector or an axial-vector current for the mass region Mπee > 1.05 GeV/c2 is measured to be B(τ– → π–ντe+e–)[Mπ–e+e– > 1.05 GeV/c2] = (5.90 ± 0.53 ± 0.85 ± 0.11) × 10–6, where the first uncertainty is statistical, the second is systematic, and the third is due to model dependence. In the full phase space, due to the different detection efficiencies for the structure-dependent mechanisms mediated by axial-vector and vector currents, the branching fraction varies from BA(τ– → π–ντe+e–) = (1.46 ± 0.13 ± 0.21) × 10–5 to BV(τ– → π–ντe+e–) = (3.01 ± 0.27 ± 0.43) × 10–5, respectively. An upper limit is set on the branching fraction of the τ– → π–ντμ+μ– decay, B(τ– → π–ντμ+μ–) < 1.14 × 10–5, at the 90% confidence level.},
doi = {10.1103/PhysRevD.100.071101},
journal = {Physical Review D},
number = 7,
volume = 100,
place = {United States},
year = {2019},
month = {10}
}

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    Works referencing / citing this record:

    Observation of $τ^ − → π^ − ν_ τ e^ + e^ −$ and search for $τ ^− → π^ − ν_ τ μ ^+ μ^ −$
    text, January 2019