DOI 10.1007/s100529900117
CP-odd WWZ couplings induced by vector-like quarks
E. Asakawa1 - M. Marui2 - N. Oshimo3 - T. Saito1 - A. Sugamoto1
1 Department of Physics and
Graduate School of Humanities and Sciences,
Ochanomizu University, Otsuka 2-1-1,
Bunkyo-ku, Tokyo 112-8610, Japan
2 Faculty of Social Information Science,
Kure University, Gouhara 2411-26, Kure, Hiroshima 724-0792,
Japan
3 Institute for Cosmic Ray Research,
University of Tokyo, Midori-cho 3-2-1,
Tanashi, Tokyo 188-8502, Japan
Received: 26 February 1999 / Published oinline: 12 August 1999
Abstract
A minimal extension of the standard model includes
extra
quarks with charges 2/3 and/or -1/3, whose left-handed and
right-handed
components are both SU(2) singlets.
This model predicts new interactions of
the flavor-changing neutral current at the tree level, which
also
violate CP invariance.
We study CP-odd anomalous couplings for the W, W, and Z
gauge bosons
induced by the new interactions at the one-loop level.
These couplings become non-negligible only if
both up-type and down-type extra quarks are incorporated.
Their form factors are estimated to be maximally of order 10-5.
Such magnitudes are larger than those predicted in the standard
model,
though smaller than those in certain other models.
Copyright Springer-Verlag
