Measurement of Michel Parameter in τ Decay

BES Collaborator

Chinese Physics C> 1998, Vol. 22> Issue(11) : 961-968

Measurement of Michel Parameter in τ Decay

BES Collaborator

Institute of High Energy Physics, CAS, Beijing 100039

Abstract
HTML
Reference
Related

PDF

Abstract：
We have analysed the e⁺e^－ collision data collected with Beijing Spectrometer at the center-of-mass energy 4.03 GeV and selected e⁺e^－→τ^±τ⁺→e^±X⁺v's events, X^± required as μ^±、π^± and ρ^±. From fitting electron energy spectrum in τ→ev's decay, the measurement value of Michel parameter is given as ρ_τ→e=0.705, this result is in good agreement with the prediction of standrd Model.

References

[1]

Michel L. Proc. Phys. Soc, 1950,A63:514 [2] PDG. Review of Partical Propenies, Phys. Rev., 1996, D54:272 [3] Albrecht H et al. Phys. Lett., 1995, B341:441 [4] Derenzo et al.Phys. Rev., 1969,181:1854 [5] BES Coll. Nucl. Instr. Meth., 1994,A344:319[6] BES Coll. High Energy Phys. and Nuclear Phys. (in Chinese), 1997, 21: 193(BES合作组.高能物理与核物理,1997,21:193)[7] Ali A, Aydin Z Z. Nuovo Cimento, 1978, A43:270[8] Ye Suwei et al. High Energy Phys. and Nuclear Phys. (in Chirese), 1994, 18:577(叶树伟等.高能物理与核物理,1994,18:577)

[1]	JIANG Xiao-Guo , LI Cheng-Gang , WANG Yuan , DAI Wen-Hua , XIA Lian-Sheng , CHEN Nan , YANG Guo-Jun . Accurate Burst Trigger Mode for Dragon-Ⅰ Electron Beam Measurement System. Chinese Physics C, 2006, 30(8): 784-787.
[2]	YANG Guo-Jun , ZHANG Zhuo , CHEN Si-Fu , XU Tie-Zheng , MU Fan , lijin , JIANG Xiao-Guo . Beam Measurement of Dragon-I Linear Induction Accelerator. Chinese Physics C, 2006, 30(S1): 105-107.
[3]	OUYANG Xiao-Ping , LI Zhen-Fu , WANG Qiu-Shu , HUO Yu-Kun . Thin Plastic Scintillating Foil for Measuring Pulsed Neutron Flux in High Gamma-Ray Environment. Chinese Physics C, 2005, 29(4): 399-403.
[4]	LIU Fang , LI Jin , HUANG Yi-Bin , YAN Mu-Lin . ρ-ω Interference in J/ψ-Decays and ρ→ππ^-π⁰ Decay. Chinese Physics C, 2004, 28(3): 239-244.
[5]	WANG Wen-Feng , ZHU Yong-Sheng , ZHANG Xue-Yao . Efficiency Correction in the Branching Fraction Determination of ψ′Hadronic Decays. Chinese Physics C, 2003, 27(2): 89-94.
[6]	BES Collaboration . Measurement of Inclusive Semileptonic Branching Fractions for D^－→e^－X and D⁰→e^－X. Chinese Physics C, 2002, 26(6): 547-556.
[7]	WANG Yong-Gang , XUE Liang , FENG Cun-Feng , FU Yu , LI Jie , ZHANG Xue-Yao , LI Jin-Yu , ZHANG Nai-Jian , HE Mao , WANG Cheng-Rui , REN Jing-Ru , LU Sui-Ling . Adjustment of Parameters of Primary Cosmic Ray Energy Spectrum with Recent Direct Measurments. Chinese Physics C, 2002, 26(2): 108-115.
[8]	XING Zhi-Zhong . Determining the Factorization Parameter and Strong Phase Differences in B→D^(*)π Decays. Chinese Physics C, 2002, 26(2): 100-103.
[9]	ZHANG Jing-Bo , HUO Lei , ZHANG Wei-Ning , LIU Yi-Ming . HBT Parameters for Au+Au Collisions at RHIC Energy. Chinese Physics C, 2001, 25(12): 1253-1257.
[10]	ZHANG Xin-Min . Probing for New Physics in J/ψ Decays. Chinese Physics C, 2001, 25(5): 461-464.
[11]	ZHANG ChangChun , LI WeiGuo , MAO HuiShun , GU JianHui , LI XiaoNan , RONG Gang . Absolute Measurement of Important Branching Fractions of the D_s Meson. Chinese Physics C, 2000, 24(6): 593-608.
[12]	Guo Hua . In-medium QMC Model Parameters and Quark Condensation in Nuclear Matter. Chinese Physics C, 1999, 23(5): 459-468.
[13]	BES Collaboration . Measurements of the Branching Ratios for the Decays J/ψ→γπ⁰,γη, γη'→ 3γ at BES. Chinese Physics C, 1997, 21(5): 385-392.
[14]	BES Collaboration . Measurement of the Branching Ratios of τ^±→π^±+nπ⁰+ν_τ(n=0,1,2) decays. Chinese Physics C, 1997, 21(3): 193-200.
[15]	Yu Hong , Shen Qixing . Multi-channel Coupling in the Hadronic Decay Process J/ψ→ωπ⁺π^－. Chinese Physics C, 1997, 21(2): 123-129.
[16]	BES Collaboration . Determination of J/ψ Leptonic Branching Fraction Via ψ(2S)→π⁺π^－J/ψ. Chinese Physics C, 1996, 20(2): 97-106.
[17]	He Zhiyong , Jin Genming , Li Zuyu , Duan Limin , Wu Heyu , Dai Guangxi , Zhang Baoguo , Wen Wanxin , Qi Yujin , Luo Qingzheng . Emission Time of Light Particles and Lifetime of Hot Nuclei Followed by Binary Fission. Chinese Physics C, 1996, 20(7): 596-600.
[18]	BES Collaboration . Measurement of D_s Decay Constant. Chinese Physics C, 1996, 20(3): 193-203.
[19]	BES collaboration . Study of the Decay τ±→π+π-π±υτ at s=4.03 GeV. Chinese Physics C, 1995, 19(5): 385-392.
[20]	YUE Chongxing , LU Gongru . Investigation of Technivector Mesons Decay. Chinese Physics C, 1993, 17(11): 1002-1010.

Access

Get Citation

BES Collaborator. Measurement of Michel Parameter in τ Decay[J]. Chinese Physics C, 1998, 22(11): 961-968.

BES Collaborator. Measurement of Michel Parameter in τ Decay[J]. Chinese Physics C, 1998, 22(11): 961-968. shu

RIS(for EndNote,Reference Manager,ProCite)

BibTex

Txt

Milestone

Received: 1997-12-03
Revised: 1900-01-01

Article Metric

Article Views(3151)
PDF Downloads(494)
Cited by(0)

Policy on re-use

To reuse of subscription content published by CPC, the users need to request permission from CPC, unless the content was published under an Open Access license which automatically permits that type of reuse.

通讯作者: 陈斌, bchen63@163.com

1.
沈阳化工大学材料科学与工程学院沈阳 110142

Measurement of Michel Parameter in τ Decay

BES Collaborator

Institute of High Energy Physics, CAS, Beijing 100039

Received Date: 1997-12-03
Accepted Date: 1900-01-01
Available Online: 1998-11-05

Abstract: We have analysed the e⁺e^－ collision data collected with Beijing Spectrometer at the center-of-mass energy 4.03 GeV and selected e⁺e^－→τ^±τ⁺→e^±X⁺v's events, X^± required as μ^±、π^± and ρ^±. From fitting electron energy spectrum in τ→ev's decay, the measurement value of Michel parameter is given as ρ_τ→e=0.705, this result is in good agreement with the prediction of standrd Model.