A Measurement of the Michel Parameters in Leptonic Decays of the Tau

Journal Article · Sun Jun 01 00:00:00 EDT 1997 · Physical Review Letters

DOI:https://doi.org/10.1103/PhysRevLett.78.4686· OSTI ID:628687

Ammar, R; Baringer, P; Bean, A; Besson, D; Coppage, D; Darling, C; Davis, R; Hancock, N; Kotov, S; Kravchenko, I; Kwak, N ^[1]; Anderson, S; Kubota, Y; Lattery, M; ONeill, J J; Patton, S; Poling, R; Riehle, T; Savinov, V; Smith, A ^[2] ; Alam, M S; Athar, S B; Ling, Z; Mahmood, A H; Severini, H; Timm, S; Wappler, F ^[3]; Anastassov, A; Blinov, S; Duboscq, J E; Fujino, D; Fulton, R; Gan, K K; Hart, T; Honscheid, K; Kagan, H; Kass, R; Lee, J; Spencer, M B; Sung, M; Undrus, A; Wanke, R; Wolf, A; Zoeller, M ^[4]; Nemati, B; Richichi, S J; Ross, W R; Skubic, P; Wood, M ^[5]; Bishai, M; Fast, J; Gerndt, E; Hinson, J W; Menon, N; Miller, D H; Shibata, E I; Shipsey, I P ^[6]; Yurko, M; Gibbons, L; Johnson, S D; Kwon, Y; Roberts, S; Thorndike, E H ^[7]; Jessop, C P; Lingel, K; Marsiske, H; Perl, M L; Schaffner, S F; Ugolini, D; Wang, R; Zhou, X ^[8]; Coan, T E; Fadeyev, V; Korolkov, I; Maravin, Y; Narsky, I; Shelkov, V; Staeck, J; Stroynowski, R; Volobouev, I; Ye, J ^[9]; Artuso, M; Efimov, A; Frasconi, F; Gao, M; Goldberg, M; He, D; Kopp, S; Moneti, G C; Mountain, R; Mukhin, Y; Schuh, S; Skwarnicki, T; Stone, S; Viehhauser, G; Xing, X ^[10]; Bartelt, J; Csorna, S E; Jain, V; others, and

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1. University of Kansas, Lawrence, Kansas 66045 (United States)
2. University of Minnesota, Minneapolis, Minnesota 55455 (United States)
3. State University of New York at Albany, Albany, New York 12222 (United States)
4. Ohio State University, Columbus, Ohio 43210 (United States)
5. University of Oklahoma, Norman, Oklahoma 73019 (United States)
6. Purdue University, West Lafayette, Indiana 47907 (United States)
7. University of Rochester, Rochester, New York 14627 (United States)
8. Stanford Linear Accelerator Center, Stanford University, Stanford, California 94309 (United States)
9. Southern Methodist University, Dallas, Texas 75275 (United States)
10. Syracuse University, Syracuse, New York 13244 (United States)

We have measured the spectral shape Michel parameters {rho} and {eta} using leptonic decays of the {tau} , recorded by the CLEO II detector. Assuming e-{mu} universality in the vectorlike couplings, we find {rho}{sub e{mu}}=0.735{plus_minus}0.013{plus_minus}0.008 and {eta}{sub e{mu}}=-0.015{plus_minus}0.061{plus_minus}0.062 , where the first error is statistical and the second systematic. We also present measurements for the parameters for e and {mu} final states separately. {copyright} {ital 1997} {ital The American Physical Society}

• OSTI ID: 628687
• Journal Information: Physical Review Letters, Vol. 78, Issue 25; Other Information: PBD: Jun 1997
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
TAU PARTICLES
LEPTONIC DECAY
SPECTRAL FUNCTIONS
SHAPE
HIGGS BOSONS
MASS