On the mass and width of the Z-boson and other relativistic quasistable particles

被引：32

作者：

Bohm, AR ^{[1
]}

Harshman, NL ^{[1
]}

机构：

[1] Univ Texas, Austin, TX 78712 USA

来源：

NUCLEAR PHYSICS B | 2000年 / 581卷 / 1-2期

关键词：

Z-boson lineshape; relativistic Breit-Wigner; relativistic resonances; relativistic Gamow vector; Poincare semigroup; time asymmetry;

D O I：

10.1016/S0550-3213(00)00249-2

中图分类号：

O412 [相对论、场论]; O572.2 [粒子物理学];

学科分类号：

摘要：

The ambiguity in the definition for the mass and width of relativistic resonances is discussed, in particular for the case of the Z-boson. This ambiguity can be removed by requiring that a resonance's width Gamma (defined by a Breit-Wigner lineshape) and lifetime tau (defined by the exponential law) always and exactly fulfill the relation Gamma = (h) over bar/tau. To justify this, one needs relativistic Gamow vectors which in turn define the resonance's mass M-R as the real part of the square root Re root s(R) of the S-matrix pole position s(R). For the Z-boson this means that M-R approximate to M-Z - 26 MeV and Gamma(R) approximate to Gamma(Z) - 1.2 MeV where M-Z and Gamma(Z) are the values reported in the particle data tables. (C) 2000 Elsevier Science B.V. All rights reserved.

引用

页码：91 / 115

页数：25

共 63 条

[51]

SIRLIN A, 1998, P 4 INT S RAD CORR R

[52] GAUGE-INVARIANCE, ANALYTICITY AND PHYSICAL OBSERVABLES AT THE Z0 RESONANCE [J].