Measurement of branching ratios and τ polarization from τ→eνν-,τ→μνν-,andτ→π(K)ν decays at LEP

G. Alexander, J. Allison, P. P. Allport, K. J. Anderson, S. Arcelli, J. C. Armitage, P. Ashton, A. Astbury, D. Axen, G. Azuelos, G. A. Bahan, J. T.M. Baines, A. H. Ball, J. Banks, G. J. Barker, R. J. Barlow, J. R. Batley, G. Beaudoin, A. Beck, J. BeckerT. Behnke, K. W. Bell, G. Bella, S. Bethke, O. Biebel, U. Binder, I. J. Bloodworth, P. Bock, H. M. Bosch, S. Bougerolle, B. B. Brabson, H. Breuker, R. M. Brown, R. Brun, A. Buijs, H. J. Burckhart, P. Capiluppi, R. K. Carnegie, A. A. Carter, J. R. Carter, C. Y. Chang, D. G. Charlton, J. T.M. Chrin, P. E.L. Clarke, I. Cohen, W. J. Collins, J. E. Conboy, M. Cooper, M. Couch, M. Coupland, M. Cuffiani, S. Dado, G. M. Dallavalle, S. De Jong, P. Debu, M. M. Deninno, A. Dieckmann, M. Dittmar, M. S. Dixit, E. Duchovni, G. Duckeck, I. P. Duerdoth, D. J.P. Dumas, G. Eckerlin, P. A. Elcombe, P. G. Estabrooks, E. Etzion, F. Fabbri, M. Fincke-Keeler, H. M. Fischer, D. G. Fong, C. Fukunaga, A. Gaidot, O. Ganel, J. W. Gary, J. Gascon, R. F. McGowan, N. I. Geddes, C. Geich-Gimbel, S. W. Gensler, F. X. Gentit, G. Giacomelli, V. Gibson, W. R. Gibson, J. D. Gillies, J. Goldberg, M. J. Goodrick, W. Gorn, C. Grandi, E. Gross, J. Hagemann, G. G. Hanson, M. Hansroul, C. K. Hargrove, P. F. Harrison, J. Hart, P. M. Hattersley, M. Hauschild, C. M. Hawkes, E. Heflin, R. J. Hemingway, R. D. Heuer, J. C. Hill, S. J. Hillier, D. A. Hinshaw, C. Ho, J. D. Hobbs, P. R. Hobson, D. Hochman, B. Holl, R. J. Homer, S. R. Hou, C. P. Howarth, R. E. Hughes-Jones, R. Humbert, P. Igo-Kemenes, H. Ihssen, D. C. Imrie, L. Janissen, A. Jawahery, P. W. Jeffreys, H. Jeremie, M. Jimack, M. Jobes, R. W.L. Jones, P. Jovanovic, D. Karlen, K. Kawagoe, T. Kawamoto, R. K. Keeler, R. G. Kellogg, B. W. Kennedy, C. Kleinwort, D. E. Klem, T. Kobayashi, T. P. Kokott, Sachio Komamiya, L. Köpke, R. Kowalewski, H. Kreutzmann, J. von Krogh, J. Kroll, M. Kuwano, P. Kyberd, G. D. Lafferty, F. Lamarche, W. J. Larson, J. G. Layter, P. Le Du, P. Leblanc, A. M. Lee, M. H. Lehto, D. Lellouch, P. Lennert, C. Leroy, L. Lessard, S. Levegrün, L. Levinson, S. L. Lloyd, F. K. Loebinger, J. M. Lorah, B. Lorazo, M. J. Losty, X. C. Lou, J. Ludwig, M. Mannelli, S. Marcellini, G. Maringer, A. J. Martin, J. P. Martin, T. Mashimo, P. Mättig, U. Maur, T. J. McMahon, J. R. McNutt, F. Meijers, D. Menszner, F. S. Merritt, H. Mes, A. Michelini, R. P. Middleton, G. Mikenberg, J. Mildenberger, D. J. Miller, C. Milstene, R. Mir, W. Mohr, C. Moisan, A. Montanari, T. Mori, M. W. Moss, T. Mouthuy, P. G. Murphy, B. Nellen, H. H. Nguyen, M. Nozaki, S. W. O'Neale, B. P. O'Neill, F. G. Oakham, F. Odorici, M. Ogg, H. O. Ogren, H. Oh, C. J. Oram, M. J. Oreglia, S. Orito, J. P. Pansart, B. Panzer-Steindel, P. Paschievici, G. N. Patrick, S. J. Pawley, P. Pfister, J. E. Pilcher, J. L. Pinfold, D. E. Plane, P. Poffenberger, B. Poli, A. Pouladdej, E. Prebys, T. W. Pritchard, H. Przysiezniak, G. Quast, M. W. Redmond, D. L. Rees, K. Riles, S. A. Robins, D. Robinson, A. Rollnik, J. M. Roney, S. Rossberg, A. M. Rossi, P. Routenburg, K. Runge, O. Runolfsson, D. R. Rust, S. Sanghera, M. Sasaki, A. D. Schaile, O. Schaile, W. Schappert, P. Scharff-Hansen, P. Schenk, H. von der Schmitt, S. Schreiber, J. Schwarz, W. G. Scott, M. Settles, B. C. Shen, P. Sherwood, R. Shypit, A. Simon, P. Singh, G. P. Siroli, A. Skuja, A. M. Smith, T. J. Smith, G. A. Snow, R. Sobie, R. W. Springer, M. Sproston, K. Stephens, H. E. Stier, D. Strom, H. Takeda, T. Takeshita, P. Taras, S. Tarem, P. Teixeira-Dias, N. J. Thackray, T. Tsukamoto, M. F. Turner, G. Tysarczyk-Niemeyer, D. Van den plas, R. Van Kooten, G. J. VanDalen, G. Vasseur, C. J. Virtue, A. Wagner, C. Wahl, J. P. Walker, C. P. Ward, D. R. Ward, P. M. Watkins, A. T. Watson, N. K. Watson, M. Weber, S. Weisz, P. S. Wells, N. Wermes, M. Weymann, M. A. Whalley, G. W. Wilson, J. A. Wilson, I. Wingerter, V. H. Winterer, N. C. Wood, S. Wotton, T. R. Wyatt, R. Yaari, Y. Yang, G. Yekutieli, I. Zacharov, W. Zeuner, G. T. Zorn

研究成果: Article

74 引用 (Scopus)

抄録

From a sample of 3308 e+e- → τ+τ- events with an estimated background of 1.9%, we find 964 τ → eνν, 903 τ → μνν, and 309 τ → π(K)ν candidates. Efficiency and background estimates determined from both Monte Carlo and control sample studies yield the following branching ratios: B(τ → eνν) = 17.4 ± 0.5 (stat) ± 0.4 (sys)%, B(τ → μνν) = 16.8 ± 0.5 ± 0.4%, and B(τ → π(K)ν) = 12.1 ± 0.7 ± 0.5%. These values are in good agreement with previous measurements. The measured lepton branching ratios, when combined with the world-average measured value for the τ lifetime, yield a ratio of the τ Fermi coupling constant to that of the lighter leptons given by Gτ/Ge,μ = 0.92 ± 0.04, where it is assumed Ge = Gμ ≡ Ge,μ. The average τ polarization at the Z° resonance is measured to be -0.01±0.09 from an analysis of the momentum spectra of the electron, muon, and pion candidates, implying that the ratio of vector to axial vector couplings of the τ to the Z° is νττ = 0.01 ± 0.04. The measurements of the average polarizations in the forward and backward hemispheres lead to the efficiency-corrected, forward-backward polarization asymmetry AFB pol = -0.22 ± 0.10, implying for the electron couplings to the Z° the ratio νee = 0.15±0.07. Since these values for the tau and electron couplings are consistent with one another, we assume lepton universality to derive ν/α = 0.05 ± 0.04 and a value for the weak mixing angle of sin2θW = 0.237 ± 0.009, with no ambiguity introduced by the relative signs of ν and α.

元の言語English
ページ(範囲)201-217
ページ数17
ジャーナルPhysics Letters B
266
発行部数1-2
DOI
出版物ステータスPublished - 1991 8 22
外部発表Yes

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leptons
decay
polarization
electrons
hemispheres
ambiguity
muons
pions
asymmetry
momentum
life (durability)
estimates

ASJC Scopus subject areas

  • Nuclear and High Energy Physics

これを引用

Alexander, G., Allison, J., Allport, P. P., Anderson, K. J., Arcelli, S., Armitage, J. C., ... Zorn, G. T. (1991). Measurement of branching ratios and τ polarization from τ→eνν-,τ→μνν-,andτ→π(K)ν decays at LEP. Physics Letters B, 266(1-2), 201-217. https://doi.org/10.1016/0370-2693(91)90768-L

Measurement of branching ratios and τ polarization from τ→eνν-,τ→μνν-,andτ→π(K)ν decays at LEP. / Alexander, G.; Allison, J.; Allport, P. P.; Anderson, K. J.; Arcelli, S.; Armitage, J. C.; Ashton, P.; Astbury, A.; Axen, D.; Azuelos, G.; Bahan, G. A.; Baines, J. T.M.; Ball, A. H.; Banks, J.; Barker, G. J.; Barlow, R. J.; Batley, J. R.; Beaudoin, G.; Beck, A.; Becker, J.; Behnke, T.; Bell, K. W.; Bella, G.; Bethke, S.; Biebel, O.; Binder, U.; Bloodworth, I. J.; Bock, P.; Bosch, H. M.; Bougerolle, S.; Brabson, B. B.; Breuker, H.; Brown, R. M.; Brun, R.; Buijs, A.; Burckhart, H. J.; Capiluppi, P.; Carnegie, R. K.; Carter, A. A.; Carter, J. R.; Chang, C. Y.; Charlton, D. G.; Chrin, J. T.M.; Clarke, P. E.L.; Cohen, I.; Collins, W. J.; Conboy, J. E.; Cooper, M.; Couch, M.; Coupland, M.; Cuffiani, M.; Dado, S.; Dallavalle, G. M.; De Jong, S.; Debu, P.; Deninno, M. M.; Dieckmann, A.; Dittmar, M.; Dixit, M. S.; Duchovni, E.; Duckeck, G.; Duerdoth, I. P.; Dumas, D. J.P.; Eckerlin, G.; Elcombe, P. A.; Estabrooks, P. G.; Etzion, E.; Fabbri, F.; Fincke-Keeler, M.; Fischer, H. M.; Fong, D. G.; Fukunaga, C.; Gaidot, A.; Ganel, O.; Gary, J. W.; Gascon, J.; McGowan, R. F.; Geddes, N. I.; Geich-Gimbel, C.; Gensler, S. W.; Gentit, F. X.; Giacomelli, G.; Gibson, V.; Gibson, W. R.; Gillies, J. D.; Goldberg, J.; Goodrick, M. J.; Gorn, W.; Grandi, C.; Gross, E.; Hagemann, J.; Hanson, G. G.; Hansroul, M.; Hargrove, C. K.; Harrison, P. F.; Hart, J.; Hattersley, P. M.; Hauschild, M.; Hawkes, C. M.; Heflin, E.; Hemingway, R. J.; Heuer, R. D.; Hill, J. C.; Hillier, S. J.; Hinshaw, D. A.; Ho, C.; Hobbs, J. D.; Hobson, P. R.; Hochman, D.; Holl, B.; Homer, R. J.; Hou, S. R.; Howarth, C. P.; Hughes-Jones, R. E.; Humbert, R.; Igo-Kemenes, P.; Ihssen, H.; Imrie, D. C.; Janissen, L.; Jawahery, A.; Jeffreys, P. W.; Jeremie, H.; Jimack, M.; Jobes, M.; Jones, R. W.L.; Jovanovic, P.; Karlen, D.; Kawagoe, K.; Kawamoto, T.; Keeler, R. K.; Kellogg, R. G.; Kennedy, B. W.; Kleinwort, C.; Klem, D. E.; Kobayashi, T.; Kokott, T. P.; Komamiya, Sachio; Köpke, L.; Kowalewski, R.; Kreutzmann, H.; von Krogh, J.; Kroll, J.; Kuwano, M.; Kyberd, P.; Lafferty, G. D.; Lamarche, F.; Larson, W. J.; Layter, J. G.; Le Du, P.; Leblanc, P.; Lee, A. M.; Lehto, M. H.; Lellouch, D.; Lennert, P.; Leroy, C.; Lessard, L.; Levegrün, S.; Levinson, L.; Lloyd, S. L.; Loebinger, F. K.; Lorah, J. M.; Lorazo, B.; Losty, M. J.; Lou, X. C.; Ludwig, J.; Mannelli, M.; Marcellini, S.; Maringer, G.; Martin, A. J.; Martin, J. P.; Mashimo, T.; Mättig, P.; Maur, U.; McMahon, T. J.; McNutt, J. R.; Meijers, F.; Menszner, D.; Merritt, F. S.; Mes, H.; Michelini, A.; Middleton, R. P.; Mikenberg, G.; Mildenberger, J.; Miller, D. J.; Milstene, C.; Mir, R.; Mohr, W.; Moisan, C.; Montanari, A.; Mori, T.; Moss, M. W.; Mouthuy, T.; Murphy, P. G.; Nellen, B.; Nguyen, H. H.; Nozaki, M.; O'Neale, S. W.; O'Neill, B. P.; Oakham, F. G.; Odorici, F.; Ogg, M.; Ogren, H. O.; Oh, H.; Oram, C. J.; Oreglia, M. J.; Orito, S.; Pansart, J. P.; Panzer-Steindel, B.; Paschievici, P.; Patrick, G. N.; Pawley, S. J.; Pfister, P.; Pilcher, J. E.; Pinfold, J. L.; Plane, D. E.; Poffenberger, P.; Poli, B.; Pouladdej, A.; Prebys, E.; Pritchard, T. W.; Przysiezniak, H.; Quast, G.; Redmond, M. W.; Rees, D. L.; Riles, K.; Robins, S. A.; Robinson, D.; Rollnik, A.; Roney, J. M.; Rossberg, S.; Rossi, A. M.; Routenburg, P.; Runge, K.; Runolfsson, O.; Rust, D. R.; Sanghera, S.; Sasaki, M.; Schaile, A. D.; Schaile, O.; Schappert, W.; Scharff-Hansen, P.; Schenk, P.; von der Schmitt, H.; Schreiber, S.; Schwarz, J.; Scott, W. G.; Settles, M.; Shen, B. C.; Sherwood, P.; Shypit, R.; Simon, A.; Singh, P.; Siroli, G. P.; Skuja, A.; Smith, A. M.; Smith, T. J.; Snow, G. A.; Sobie, R.; Springer, R. W.; Sproston, M.; Stephens, K.; Stier, H. E.; Strom, D.; Takeda, H.; Takeshita, T.; Taras, P.; Tarem, S.; Teixeira-Dias, P.; Thackray, N. J.; Tsukamoto, T.; Turner, M. F.; Tysarczyk-Niemeyer, G.; Van den plas, D.; Van Kooten, R.; VanDalen, G. J.; Vasseur, G.; Virtue, C. J.; Wagner, A.; Wahl, C.; Walker, J. P.; Ward, C. P.; Ward, D. R.; Watkins, P. M.; Watson, A. T.; Watson, N. K.; Weber, M.; Weisz, S.; Wells, P. S.; Wermes, N.; Weymann, M.; Whalley, M. A.; Wilson, G. W.; Wilson, J. A.; Wingerter, I.; Winterer, V. H.; Wood, N. C.; Wotton, S.; Wyatt, T. R.; Yaari, R.; Yang, Y.; Yekutieli, G.; Zacharov, I.; Zeuner, W.; Zorn, G. T.

:: Physics Letters B, 巻 266, 番号 1-2, 22.08.1991, p. 201-217.

研究成果: Article

Alexander, G, Allison, J, Allport, PP, Anderson, KJ, Arcelli, S, Armitage, JC, Ashton, P, Astbury, A, Axen, D, Azuelos, G, Bahan, GA, Baines, JTM, Ball, AH, Banks, J, Barker, GJ, Barlow, RJ, Batley, JR, Beaudoin, G, Beck, A, Becker, J, Behnke, T, Bell, KW, Bella, G, Bethke, S, Biebel, O, Binder, U, Bloodworth, IJ, Bock, P, Bosch, HM, Bougerolle, S, Brabson, BB, Breuker, H, Brown, RM, Brun, R, Buijs, A, Burckhart, HJ, Capiluppi, P, Carnegie, RK, Carter, AA, Carter, JR, Chang, CY, Charlton, DG, Chrin, JTM, Clarke, PEL, Cohen, I, Collins, WJ, Conboy, JE, Cooper, M, Couch, M, Coupland, M, Cuffiani, M, Dado, S, Dallavalle, GM, De Jong, S, Debu, P, Deninno, MM, Dieckmann, A, Dittmar, M, Dixit, MS, Duchovni, E, Duckeck, G, Duerdoth, IP, Dumas, DJP, Eckerlin, G, Elcombe, PA, Estabrooks, PG, Etzion, E, Fabbri, F, Fincke-Keeler, M, Fischer, HM, Fong, DG, Fukunaga, C, Gaidot, A, Ganel, O, Gary, JW, Gascon, J, McGowan, RF, Geddes, NI, Geich-Gimbel, C, Gensler, SW, Gentit, FX, Giacomelli, G, Gibson, V, Gibson, WR, Gillies, JD, Goldberg, J, Goodrick, MJ, Gorn, W, Grandi, C, Gross, E, Hagemann, J, Hanson, GG, Hansroul, M, Hargrove, CK, Harrison, PF, Hart, J, Hattersley, PM, Hauschild, M, Hawkes, CM, Heflin, E, Hemingway, RJ, Heuer, RD, Hill, JC, Hillier, SJ, Hinshaw, DA, Ho, C, Hobbs, JD, Hobson, PR, Hochman, D, Holl, B, Homer, RJ, Hou, SR, Howarth, CP, Hughes-Jones, RE, Humbert, R, Igo-Kemenes, P, Ihssen, H, Imrie, DC, Janissen, L, Jawahery, A, Jeffreys, PW, Jeremie, H, Jimack, M, Jobes, M, Jones, RWL, Jovanovic, P, Karlen, D, Kawagoe, K, Kawamoto, T, Keeler, RK, Kellogg, RG, Kennedy, BW, Kleinwort, C, Klem, DE, Kobayashi, T, Kokott, TP, Komamiya, S, Köpke, L, Kowalewski, R, Kreutzmann, H, von Krogh, J, Kroll, J, Kuwano, M, Kyberd, P, Lafferty, GD, Lamarche, F, Larson, WJ, Layter, JG, Le Du, P, Leblanc, P, Lee, AM, Lehto, MH, Lellouch, D, Lennert, P, Leroy, C, Lessard, L, Levegrün, S, Levinson, L, Lloyd, SL, Loebinger, FK, Lorah, JM, Lorazo, B, Losty, MJ, Lou, XC, Ludwig, J, Mannelli, M, Marcellini, S, Maringer, G, Martin, AJ, Martin, JP, Mashimo, T, Mättig, P, Maur, U, McMahon, TJ, McNutt, JR, Meijers, F, Menszner, D, Merritt, FS, Mes, H, Michelini, A, Middleton, RP, Mikenberg, G, Mildenberger, J, Miller, DJ, Milstene, C, Mir, R, Mohr, W, Moisan, C, Montanari, A, Mori, T, Moss, MW, Mouthuy, T, Murphy, PG, Nellen, B, Nguyen, HH, Nozaki, M, O'Neale, SW, O'Neill, BP, Oakham, FG, Odorici, F, Ogg, M, Ogren, HO, Oh, H, Oram, CJ, Oreglia, MJ, Orito, S, Pansart, JP, Panzer-Steindel, B, Paschievici, P, Patrick, GN, Pawley, SJ, Pfister, P, Pilcher, JE, Pinfold, JL, Plane, DE, Poffenberger, P, Poli, B, Pouladdej, A, Prebys, E, Pritchard, TW, Przysiezniak, H, Quast, G, Redmond, MW, Rees, DL, Riles, K, Robins, SA, Robinson, D, Rollnik, A, Roney, JM, Rossberg, S, Rossi, AM, Routenburg, P, Runge, K, Runolfsson, O, Rust, DR, Sanghera, S, Sasaki, M, Schaile, AD, Schaile, O, Schappert, W, Scharff-Hansen, P, Schenk, P, von der Schmitt, H, Schreiber, S, Schwarz, J, Scott, WG, Settles, M, Shen, BC, Sherwood, P, Shypit, R, Simon, A, Singh, P, Siroli, GP, Skuja, A, Smith, AM, Smith, TJ, Snow, GA, Sobie, R, Springer, RW, Sproston, M, Stephens, K, Stier, HE, Strom, D, Takeda, H, Takeshita, T, Taras, P, Tarem, S, Teixeira-Dias, P, Thackray, NJ, Tsukamoto, T, Turner, MF, Tysarczyk-Niemeyer, G, Van den plas, D, Van Kooten, R, VanDalen, GJ, Vasseur, G, Virtue, CJ, Wagner, A, Wahl, C, Walker, JP, Ward, CP, Ward, DR, Watkins, PM, Watson, AT, Watson, NK, Weber, M, Weisz, S, Wells, PS, Wermes, N, Weymann, M, Whalley, MA, Wilson, GW, Wilson, JA, Wingerter, I, Winterer, VH, Wood, NC, Wotton, S, Wyatt, TR, Yaari, R, Yang, Y, Yekutieli, G, Zacharov, I, Zeuner, W & Zorn, GT 1991, 'Measurement of branching ratios and τ polarization from τ→eνν-,τ→μνν-,andτ→π(K)ν decays at LEP', Physics Letters B, 巻. 266, 番号 1-2, pp. 201-217. https://doi.org/10.1016/0370-2693(91)90768-L
Alexander G, Allison J, Allport PP, Anderson KJ, Arcelli S, Armitage JC その他. Measurement of branching ratios and τ polarization from τ→eνν-,τ→μνν-,andτ→π(K)ν decays at LEP. Physics Letters B. 1991 8 22;266(1-2):201-217. https://doi.org/10.1016/0370-2693(91)90768-L
Alexander, G. ; Allison, J. ; Allport, P. P. ; Anderson, K. J. ; Arcelli, S. ; Armitage, J. C. ; Ashton, P. ; Astbury, A. ; Axen, D. ; Azuelos, G. ; Bahan, G. A. ; Baines, J. T.M. ; Ball, A. H. ; Banks, J. ; Barker, G. J. ; Barlow, R. J. ; Batley, J. R. ; Beaudoin, G. ; Beck, A. ; Becker, J. ; Behnke, T. ; Bell, K. W. ; Bella, G. ; Bethke, S. ; Biebel, O. ; Binder, U. ; Bloodworth, I. J. ; Bock, P. ; Bosch, H. M. ; Bougerolle, S. ; Brabson, B. B. ; Breuker, H. ; Brown, R. M. ; Brun, R. ; Buijs, A. ; Burckhart, H. J. ; Capiluppi, P. ; Carnegie, R. K. ; Carter, A. A. ; Carter, J. R. ; Chang, C. Y. ; Charlton, D. G. ; Chrin, J. T.M. ; Clarke, P. E.L. ; Cohen, I. ; Collins, W. J. ; Conboy, J. E. ; Cooper, M. ; Couch, M. ; Coupland, M. ; Cuffiani, M. ; Dado, S. ; Dallavalle, G. M. ; De Jong, S. ; Debu, P. ; Deninno, M. M. ; Dieckmann, A. ; Dittmar, M. ; Dixit, M. S. ; Duchovni, E. ; Duckeck, G. ; Duerdoth, I. P. ; Dumas, D. J.P. ; Eckerlin, G. ; Elcombe, P. A. ; Estabrooks, P. G. ; Etzion, E. ; Fabbri, F. ; Fincke-Keeler, M. ; Fischer, H. M. ; Fong, D. G. ; Fukunaga, C. ; Gaidot, A. ; Ganel, O. ; Gary, J. W. ; Gascon, J. ; McGowan, R. F. ; Geddes, N. I. ; Geich-Gimbel, C. ; Gensler, S. W. ; Gentit, F. X. ; Giacomelli, G. ; Gibson, V. ; Gibson, W. R. ; Gillies, J. D. ; Goldberg, J. ; Goodrick, M. J. ; Gorn, W. ; Grandi, C. ; Gross, E. ; Hagemann, J. ; Hanson, G. G. ; Hansroul, M. ; Hargrove, C. K. ; Harrison, P. F. ; Hart, J. ; Hattersley, P. M. ; Hauschild, M. ; Hawkes, C. M. ; Heflin, E. ; Hemingway, R. J. ; Heuer, R. D. ; Hill, J. C. ; Hillier, S. J. ; Hinshaw, D. A. ; Ho, C. ; Hobbs, J. D. ; Hobson, P. R. ; Hochman, D. ; Holl, B. ; Homer, R. J. ; Hou, S. R. ; Howarth, C. P. ; Hughes-Jones, R. E. ; Humbert, R. ; Igo-Kemenes, P. ; Ihssen, H. ; Imrie, D. C. ; Janissen, L. ; Jawahery, A. ; Jeffreys, P. W. ; Jeremie, H. ; Jimack, M. ; Jobes, M. ; Jones, R. W.L. ; Jovanovic, P. ; Karlen, D. ; Kawagoe, K. ; Kawamoto, T. ; Keeler, R. K. ; Kellogg, R. G. ; Kennedy, B. W. ; Kleinwort, C. ; Klem, D. E. ; Kobayashi, T. ; Kokott, T. P. ; Komamiya, Sachio ; Köpke, L. ; Kowalewski, R. ; Kreutzmann, H. ; von Krogh, J. ; Kroll, J. ; Kuwano, M. ; Kyberd, P. ; Lafferty, G. D. ; Lamarche, F. ; Larson, W. J. ; Layter, J. G. ; Le Du, P. ; Leblanc, P. ; Lee, A. M. ; Lehto, M. H. ; Lellouch, D. ; Lennert, P. ; Leroy, C. ; Lessard, L. ; Levegrün, S. ; Levinson, L. ; Lloyd, S. L. ; Loebinger, F. K. ; Lorah, J. M. ; Lorazo, B. ; Losty, M. J. ; Lou, X. C. ; Ludwig, J. ; Mannelli, M. ; Marcellini, S. ; Maringer, G. ; Martin, A. J. ; Martin, J. P. ; Mashimo, T. ; Mättig, P. ; Maur, U. ; McMahon, T. J. ; McNutt, J. R. ; Meijers, F. ; Menszner, D. ; Merritt, F. S. ; Mes, H. ; Michelini, A. ; Middleton, R. P. ; Mikenberg, G. ; Mildenberger, J. ; Miller, D. J. ; Milstene, C. ; Mir, R. ; Mohr, W. ; Moisan, C. ; Montanari, A. ; Mori, T. ; Moss, M. W. ; Mouthuy, T. ; Murphy, P. G. ; Nellen, B. ; Nguyen, H. H. ; Nozaki, M. ; O'Neale, S. W. ; O'Neill, B. P. ; Oakham, F. G. ; Odorici, F. ; Ogg, M. ; Ogren, H. O. ; Oh, H. ; Oram, C. J. ; Oreglia, M. J. ; Orito, S. ; Pansart, J. P. ; Panzer-Steindel, B. ; Paschievici, P. ; Patrick, G. N. ; Pawley, S. J. ; Pfister, P. ; Pilcher, J. E. ; Pinfold, J. L. ; Plane, D. E. ; Poffenberger, P. ; Poli, B. ; Pouladdej, A. ; Prebys, E. ; Pritchard, T. W. ; Przysiezniak, H. ; Quast, G. ; Redmond, M. W. ; Rees, D. L. ; Riles, K. ; Robins, S. A. ; Robinson, D. ; Rollnik, A. ; Roney, J. M. ; Rossberg, S. ; Rossi, A. M. ; Routenburg, P. ; Runge, K. ; Runolfsson, O. ; Rust, D. R. ; Sanghera, S. ; Sasaki, M. ; Schaile, A. D. ; Schaile, O. ; Schappert, W. ; Scharff-Hansen, P. ; Schenk, P. ; von der Schmitt, H. ; Schreiber, S. ; Schwarz, J. ; Scott, W. G. ; Settles, M. ; Shen, B. C. ; Sherwood, P. ; Shypit, R. ; Simon, A. ; Singh, P. ; Siroli, G. P. ; Skuja, A. ; Smith, A. M. ; Smith, T. J. ; Snow, G. A. ; Sobie, R. ; Springer, R. W. ; Sproston, M. ; Stephens, K. ; Stier, H. E. ; Strom, D. ; Takeda, H. ; Takeshita, T. ; Taras, P. ; Tarem, S. ; Teixeira-Dias, P. ; Thackray, N. J. ; Tsukamoto, T. ; Turner, M. F. ; Tysarczyk-Niemeyer, G. ; Van den plas, D. ; Van Kooten, R. ; VanDalen, G. J. ; Vasseur, G. ; Virtue, C. J. ; Wagner, A. ; Wahl, C. ; Walker, J. P. ; Ward, C. P. ; Ward, D. R. ; Watkins, P. M. ; Watson, A. T. ; Watson, N. K. ; Weber, M. ; Weisz, S. ; Wells, P. S. ; Wermes, N. ; Weymann, M. ; Whalley, M. A. ; Wilson, G. W. ; Wilson, J. A. ; Wingerter, I. ; Winterer, V. H. ; Wood, N. C. ; Wotton, S. ; Wyatt, T. R. ; Yaari, R. ; Yang, Y. ; Yekutieli, G. ; Zacharov, I. ; Zeuner, W. ; Zorn, G. T. / Measurement of branching ratios and τ polarization from τ→eνν-,τ→μνν-,andτ→π(K)ν decays at LEP. :: Physics Letters B. 1991 ; 巻 266, 番号 1-2. pp. 201-217.
@article{85240a539c644e0db9dd21600dfbd63f,
title = "Measurement of branching ratios and τ polarization from τ→eνν-,τ→μνν-,andτ→π(K)ν decays at LEP",
abstract = "From a sample of 3308 e+e- → τ+τ- events with an estimated background of 1.9{\%}, we find 964 τ → eνν, 903 τ → μνν, and 309 τ → π(K)ν candidates. Efficiency and background estimates determined from both Monte Carlo and control sample studies yield the following branching ratios: B(τ → eνν) = 17.4 ± 0.5 (stat) ± 0.4 (sys){\%}, B(τ → μνν) = 16.8 ± 0.5 ± 0.4{\%}, and B(τ → π(K)ν) = 12.1 ± 0.7 ± 0.5{\%}. These values are in good agreement with previous measurements. The measured lepton branching ratios, when combined with the world-average measured value for the τ lifetime, yield a ratio of the τ Fermi coupling constant to that of the lighter leptons given by Gτ/Ge,μ = 0.92 ± 0.04, where it is assumed Ge = Gμ ≡ Ge,μ. The average τ polarization at the Z° resonance is measured to be -0.01±0.09 from an analysis of the momentum spectra of the electron, muon, and pion candidates, implying that the ratio of vector to axial vector couplings of the τ to the Z° is ντ/ατ = 0.01 ± 0.04. The measurements of the average polarizations in the forward and backward hemispheres lead to the efficiency-corrected, forward-backward polarization asymmetry AFB pol = -0.22 ± 0.10, implying for the electron couplings to the Z° the ratio νe/αe = 0.15±0.07. Since these values for the tau and electron couplings are consistent with one another, we assume lepton universality to derive ν/α = 0.05 ± 0.04 and a value for the weak mixing angle of sin2θW = 0.237 ± 0.009, with no ambiguity introduced by the relative signs of ν and α.",
author = "G. Alexander and J. Allison and Allport, {P. P.} and Anderson, {K. J.} and S. Arcelli and Armitage, {J. C.} and P. Ashton and A. Astbury and D. Axen and G. Azuelos and Bahan, {G. A.} and Baines, {J. T.M.} and Ball, {A. H.} and J. Banks and Barker, {G. J.} and Barlow, {R. J.} and Batley, {J. R.} and G. Beaudoin and A. Beck and J. Becker and T. Behnke and Bell, {K. W.} and G. Bella and S. Bethke and O. Biebel and U. Binder and Bloodworth, {I. J.} and P. Bock and Bosch, {H. M.} and S. Bougerolle and Brabson, {B. B.} and H. Breuker and Brown, {R. M.} and R. Brun and A. Buijs and Burckhart, {H. J.} and P. Capiluppi and Carnegie, {R. K.} and Carter, {A. A.} and Carter, {J. R.} and Chang, {C. Y.} and Charlton, {D. G.} and Chrin, {J. T.M.} and Clarke, {P. E.L.} and I. Cohen and Collins, {W. J.} and Conboy, {J. E.} and M. Cooper and M. Couch and M. Coupland and M. Cuffiani and S. Dado and Dallavalle, {G. M.} and {De Jong}, S. and P. Debu and Deninno, {M. M.} and A. Dieckmann and M. Dittmar and Dixit, {M. S.} and E. Duchovni and G. Duckeck and Duerdoth, {I. P.} and Dumas, {D. J.P.} and G. Eckerlin and Elcombe, {P. A.} and Estabrooks, {P. G.} and E. Etzion and F. Fabbri and M. Fincke-Keeler and Fischer, {H. M.} and Fong, {D. G.} and C. Fukunaga and A. Gaidot and O. Ganel and Gary, {J. W.} and J. Gascon and McGowan, {R. F.} and Geddes, {N. I.} and C. Geich-Gimbel and Gensler, {S. W.} and Gentit, {F. X.} and G. Giacomelli and V. Gibson and Gibson, {W. R.} and Gillies, {J. D.} and J. Goldberg and Goodrick, {M. J.} and W. Gorn and C. Grandi and E. Gross and J. Hagemann and Hanson, {G. G.} and M. Hansroul and Hargrove, {C. K.} and Harrison, {P. F.} and J. Hart and Hattersley, {P. M.} and M. Hauschild and Hawkes, {C. M.} and E. Heflin and Hemingway, {R. J.} and Heuer, {R. D.} and Hill, {J. C.} and Hillier, {S. J.} and Hinshaw, {D. A.} and C. Ho and Hobbs, {J. D.} and Hobson, {P. R.} and D. Hochman and B. Holl and Homer, {R. J.} and Hou, {S. R.} and Howarth, {C. P.} and Hughes-Jones, {R. E.} and R. Humbert and P. Igo-Kemenes and H. Ihssen and Imrie, {D. C.} and L. Janissen and A. Jawahery and Jeffreys, {P. W.} and H. Jeremie and M. Jimack and M. Jobes and Jones, {R. W.L.} and P. Jovanovic and D. Karlen and K. Kawagoe and T. Kawamoto and Keeler, {R. K.} and Kellogg, {R. G.} and Kennedy, {B. W.} and C. Kleinwort and Klem, {D. E.} and T. Kobayashi and Kokott, {T. P.} and Sachio Komamiya and L. K{\"o}pke and R. Kowalewski and H. Kreutzmann and {von Krogh}, J. and J. Kroll and M. Kuwano and P. Kyberd and Lafferty, {G. D.} and F. Lamarche and Larson, {W. J.} and Layter, {J. G.} and {Le Du}, P. and P. Leblanc and Lee, {A. M.} and Lehto, {M. H.} and D. Lellouch and P. Lennert and C. Leroy and L. Lessard and S. Levegr{\"u}n and L. Levinson and Lloyd, {S. L.} and Loebinger, {F. K.} and Lorah, {J. M.} and B. Lorazo and Losty, {M. J.} and Lou, {X. C.} and J. Ludwig and M. Mannelli and S. Marcellini and G. Maringer and Martin, {A. J.} and Martin, {J. P.} and T. Mashimo and P. M{\"a}ttig and U. Maur and McMahon, {T. J.} and McNutt, {J. R.} and F. Meijers and D. Menszner and Merritt, {F. S.} and H. Mes and A. Michelini and Middleton, {R. P.} and G. Mikenberg and J. Mildenberger and Miller, {D. J.} and C. Milstene and R. Mir and W. Mohr and C. Moisan and A. Montanari and T. Mori and Moss, {M. W.} and T. Mouthuy and Murphy, {P. G.} and B. Nellen and Nguyen, {H. H.} and M. Nozaki and O'Neale, {S. W.} and O'Neill, {B. P.} and Oakham, {F. G.} and F. Odorici and M. Ogg and Ogren, {H. O.} and H. Oh and Oram, {C. J.} and Oreglia, {M. J.} and S. Orito and Pansart, {J. P.} and B. Panzer-Steindel and P. Paschievici and Patrick, {G. N.} and Pawley, {S. J.} and P. Pfister and Pilcher, {J. E.} and Pinfold, {J. L.} and Plane, {D. E.} and P. Poffenberger and B. Poli and A. Pouladdej and E. Prebys and Pritchard, {T. W.} and H. Przysiezniak and G. Quast and Redmond, {M. W.} and Rees, {D. L.} and K. Riles and Robins, {S. A.} and D. Robinson and A. Rollnik and Roney, {J. M.} and S. Rossberg and Rossi, {A. M.} and P. Routenburg and K. Runge and O. Runolfsson and Rust, {D. R.} and S. Sanghera and M. Sasaki and Schaile, {A. D.} and O. Schaile and W. Schappert and P. Scharff-Hansen and P. Schenk and {von der Schmitt}, H. and S. Schreiber and J. Schwarz and Scott, {W. G.} and M. Settles and Shen, {B. C.} and P. Sherwood and R. Shypit and A. Simon and P. Singh and Siroli, {G. P.} and A. Skuja and Smith, {A. M.} and Smith, {T. J.} and Snow, {G. A.} and R. Sobie and Springer, {R. W.} and M. Sproston and K. Stephens and Stier, {H. E.} and D. Strom and H. Takeda and T. Takeshita and P. Taras and S. Tarem and P. Teixeira-Dias and Thackray, {N. J.} and T. Tsukamoto and Turner, {M. F.} and G. Tysarczyk-Niemeyer and {Van den plas}, D. and {Van Kooten}, R. and VanDalen, {G. J.} and G. Vasseur and Virtue, {C. J.} and A. Wagner and C. Wahl and Walker, {J. P.} and Ward, {C. P.} and Ward, {D. R.} and Watkins, {P. M.} and Watson, {A. T.} and Watson, {N. K.} and M. Weber and S. Weisz and Wells, {P. S.} and N. Wermes and M. Weymann and Whalley, {M. A.} and Wilson, {G. W.} and Wilson, {J. A.} and I. Wingerter and Winterer, {V. H.} and Wood, {N. C.} and S. Wotton and Wyatt, {T. R.} and R. Yaari and Y. Yang and G. Yekutieli and I. Zacharov and W. Zeuner and Zorn, {G. T.}",
year = "1991",
month = "8",
day = "22",
doi = "10.1016/0370-2693(91)90768-L",
language = "English",
volume = "266",
pages = "201--217",
journal = "Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics",
issn = "0370-2693",
publisher = "Elsevier",
number = "1-2",

}

TY - JOUR

T1 - Measurement of branching ratios and τ polarization from τ→eνν-,τ→μνν-,andτ→π(K)ν decays at LEP

AU - Alexander, G.

AU - Allison, J.

AU - Allport, P. P.

AU - Anderson, K. J.

AU - Arcelli, S.

AU - Armitage, J. C.

AU - Ashton, P.

AU - Astbury, A.

AU - Axen, D.

AU - Azuelos, G.

AU - Bahan, G. A.

AU - Baines, J. T.M.

AU - Ball, A. H.

AU - Banks, J.

AU - Barker, G. J.

AU - Barlow, R. J.

AU - Batley, J. R.

AU - Beaudoin, G.

AU - Beck, A.

AU - Becker, J.

AU - Behnke, T.

AU - Bell, K. W.

AU - Bella, G.

AU - Bethke, S.

AU - Biebel, O.

AU - Binder, U.

AU - Bloodworth, I. J.

AU - Bock, P.

AU - Bosch, H. M.

AU - Bougerolle, S.

AU - Brabson, B. B.

AU - Breuker, H.

AU - Brown, R. M.

AU - Brun, R.

AU - Buijs, A.

AU - Burckhart, H. J.

AU - Capiluppi, P.

AU - Carnegie, R. K.

AU - Carter, A. A.

AU - Carter, J. R.

AU - Chang, C. Y.

AU - Charlton, D. G.

AU - Chrin, J. T.M.

AU - Clarke, P. E.L.

AU - Cohen, I.

AU - Collins, W. J.

AU - Conboy, J. E.

AU - Cooper, M.

AU - Couch, M.

AU - Coupland, M.

AU - Cuffiani, M.

AU - Dado, S.

AU - Dallavalle, G. M.

AU - De Jong, S.

AU - Debu, P.

AU - Deninno, M. M.

AU - Dieckmann, A.

AU - Dittmar, M.

AU - Dixit, M. S.

AU - Duchovni, E.

AU - Duckeck, G.

AU - Duerdoth, I. P.

AU - Dumas, D. J.P.

AU - Eckerlin, G.

AU - Elcombe, P. A.

AU - Estabrooks, P. G.

AU - Etzion, E.

AU - Fabbri, F.

AU - Fincke-Keeler, M.

AU - Fischer, H. M.

AU - Fong, D. G.

AU - Fukunaga, C.

AU - Gaidot, A.

AU - Ganel, O.

AU - Gary, J. W.

AU - Gascon, J.

AU - McGowan, R. F.

AU - Geddes, N. I.

AU - Geich-Gimbel, C.

AU - Gensler, S. W.

AU - Gentit, F. X.

AU - Giacomelli, G.

AU - Gibson, V.

AU - Gibson, W. R.

AU - Gillies, J. D.

AU - Goldberg, J.

AU - Goodrick, M. J.

AU - Gorn, W.

AU - Grandi, C.

AU - Gross, E.

AU - Hagemann, J.

AU - Hanson, G. G.

AU - Hansroul, M.

AU - Hargrove, C. K.

AU - Harrison, P. F.

AU - Hart, J.

AU - Hattersley, P. M.

AU - Hauschild, M.

AU - Hawkes, C. M.

AU - Heflin, E.

AU - Hemingway, R. J.

AU - Heuer, R. D.

AU - Hill, J. C.

AU - Hillier, S. J.

AU - Hinshaw, D. A.

AU - Ho, C.

AU - Hobbs, J. D.

AU - Hobson, P. R.

AU - Hochman, D.

AU - Holl, B.

AU - Homer, R. J.

AU - Hou, S. R.

AU - Howarth, C. P.

AU - Hughes-Jones, R. E.

AU - Humbert, R.

AU - Igo-Kemenes, P.

AU - Ihssen, H.

AU - Imrie, D. C.

AU - Janissen, L.

AU - Jawahery, A.

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PY - 1991/8/22

Y1 - 1991/8/22

N2 - From a sample of 3308 e+e- → τ+τ- events with an estimated background of 1.9%, we find 964 τ → eνν, 903 τ → μνν, and 309 τ → π(K)ν candidates. Efficiency and background estimates determined from both Monte Carlo and control sample studies yield the following branching ratios: B(τ → eνν) = 17.4 ± 0.5 (stat) ± 0.4 (sys)%, B(τ → μνν) = 16.8 ± 0.5 ± 0.4%, and B(τ → π(K)ν) = 12.1 ± 0.7 ± 0.5%. These values are in good agreement with previous measurements. The measured lepton branching ratios, when combined with the world-average measured value for the τ lifetime, yield a ratio of the τ Fermi coupling constant to that of the lighter leptons given by Gτ/Ge,μ = 0.92 ± 0.04, where it is assumed Ge = Gμ ≡ Ge,μ. The average τ polarization at the Z° resonance is measured to be -0.01±0.09 from an analysis of the momentum spectra of the electron, muon, and pion candidates, implying that the ratio of vector to axial vector couplings of the τ to the Z° is ντ/ατ = 0.01 ± 0.04. The measurements of the average polarizations in the forward and backward hemispheres lead to the efficiency-corrected, forward-backward polarization asymmetry AFB pol = -0.22 ± 0.10, implying for the electron couplings to the Z° the ratio νe/αe = 0.15±0.07. Since these values for the tau and electron couplings are consistent with one another, we assume lepton universality to derive ν/α = 0.05 ± 0.04 and a value for the weak mixing angle of sin2θW = 0.237 ± 0.009, with no ambiguity introduced by the relative signs of ν and α.

AB - From a sample of 3308 e+e- → τ+τ- events with an estimated background of 1.9%, we find 964 τ → eνν, 903 τ → μνν, and 309 τ → π(K)ν candidates. Efficiency and background estimates determined from both Monte Carlo and control sample studies yield the following branching ratios: B(τ → eνν) = 17.4 ± 0.5 (stat) ± 0.4 (sys)%, B(τ → μνν) = 16.8 ± 0.5 ± 0.4%, and B(τ → π(K)ν) = 12.1 ± 0.7 ± 0.5%. These values are in good agreement with previous measurements. The measured lepton branching ratios, when combined with the world-average measured value for the τ lifetime, yield a ratio of the τ Fermi coupling constant to that of the lighter leptons given by Gτ/Ge,μ = 0.92 ± 0.04, where it is assumed Ge = Gμ ≡ Ge,μ. The average τ polarization at the Z° resonance is measured to be -0.01±0.09 from an analysis of the momentum spectra of the electron, muon, and pion candidates, implying that the ratio of vector to axial vector couplings of the τ to the Z° is ντ/ατ = 0.01 ± 0.04. The measurements of the average polarizations in the forward and backward hemispheres lead to the efficiency-corrected, forward-backward polarization asymmetry AFB pol = -0.22 ± 0.10, implying for the electron couplings to the Z° the ratio νe/αe = 0.15±0.07. Since these values for the tau and electron couplings are consistent with one another, we assume lepton universality to derive ν/α = 0.05 ± 0.04 and a value for the weak mixing angle of sin2θW = 0.237 ± 0.009, with no ambiguity introduced by the relative signs of ν and α.

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U2 - 10.1016/0370-2693(91)90768-L

DO - 10.1016/0370-2693(91)90768-L

M3 - Article

AN - SCOPUS:0040213576

VL - 266

SP - 201

EP - 217

JO - Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics

JF - Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics

SN - 0370-2693

IS - 1-2

ER -