Seiji Matsumoto

Abstract: A novel approach to study electroweak physics at one-loop level in generic SU(2)L×U(1)Y theories is introduced. It separates the 1-loop corrections into two pieces: process specific ones from vertex and box contributions, and universal ones from contributions to the gauge boson propagators. The latter are parametrized in terms of four effective form factors $$\bar e^2 (q^2 ), \bar s^2 (q^2 ), \bar g_Z^2 (q^2 )$$ and $$\bar g_W^2 (q^2 )$$ corresponding to the γγ, γZ,ZZ andWW propagators. Under the assumption that only the Standard Model contributes to the process specific corrections, the magnitudes of the four form factors are determined atq 2=0 and atq 2=m 2 by fitting to all available precision experiments. These values are then compared systematically with predictions of SU(2)L×U(1)Y theories. In all fits α s (m Z ) and $$\bar \alpha (m_Z^2 )$$ are treated as external parameters in order to keep the interpretation as flexible as possible. The treatment of the electroweak data is presented in detail together with the relevant theoretical formulae used to interpret the data. No deviation from the Standard Model has been identified. Ranges of the top quark and Higgs boson masses are derived as functions of α s (m Z ) and $$\bar \alpha (m_Z^2 )$$ . Also discussed are consequences of the recent precision measurement of the left-right asymmetry at SLC as well as the impact of a top quark mass and an improvedW mass measurement.

TL;DR: In this paper, a novel approach to study electroweak physics at one-loop level in generic SU(2)_L \times U(1)_Y$ theories is introduced.

TL;DR: In this article, the energy dependence of π ± p interactions at 8 and 16 GeV/c was investigated in terms of integrated distributions as functions of x, reduced rapidity ζ and p ⊥ 2, and double differential cross sections.

TL;DR: In this article, an analysis of the electroweak data has been carried out by including new and partly preliminary data available up to the 1996 summer conferences, and new results on the partial decay widths into �$b$¯¯¯¯ and �$c$¯¯¯¯ hadrons now offer a consistent interpretation of all data in the minimal standard model.

TL;DR: The I = 12 state of the nucleon pion system in π+p reactions leading to single pion production has been separated from the I = 32 state as discussed by the authors, and the contribution of the former to the total ππN cross section is found to decrease much less with increasing energy than that of the latter.