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Title: Unusual initial and final state effects in quantum chromodynamics: Annual performance report, July 15, 1988--February 20, 1989

Technical Report ·
OSTI ID:6207604

We have constructed symmetry tests from spin correlations functions in the sequential decay of a spin-0, or spin-1, boson into a fermion-antifermion pair such as /tau//sup +//tau//sup /minus//. A technipion and a Higgs boson can be distinguished by a 10--20% accuracy measurement of the observed leptons' energy-energy correlation function I(E/sub 1/, E/sub 2/, cos /psi//sub 12/) = S + ..gamma../sub CP/ D for the /bar /tau///tau/ decay mode with /tau//sup +-/ ..-->.. /ell//sup +-/..nu../bar /nu//. A much stronger signature occurs for H ..-->.. t/bar t/ with t ..-->.. b..mu../sup +/..nu.., t ..-->.. /bar b/..mu../sup /minus//..nu.., because if the b jet's momenta are also measured, the necessary t and /bar t/ rest frame variables can be determined. The harder lepton's energy spectrum for the decay sequence Z/sup o/ ..-->.. /tau//sup +//tau//sup /minus// ..-->.. ..mu../sup +/e/sup /minus// X is sensitive to the tau coupling parameters xi and ..cap alpha../sub H/ where xi is the Michel polarization parameter for /tau//sup /minus// ..-->.. ..gamma../sup /minus//..nu nu../sup /minus//, and ..cap alpha../sub H/ approx. = 2a/sub /tau// v/sub /tau///(a/sub /tau///sup 2/ + v/sub /tau///sup 2/) where a/sub /tau//, v/sub /tau// describe Z/sup o/ ..-->.. /tau//sup +//tau//sup /minus// at tree level. The parameters xi and ..cap alpha../sub H/ are independently determined. Due to a factorization property, radiative correction to such energy-energy correlations are as tractable as for A/sub LR/. By including two body modes, /tau//sup /minus// ..-->.. A/sup /minus//..nu.. for A = ..pi.., K, /rho/, K*, a/sub 1/, the ideal statistical error for ..cap alpha../sub H/ is reduced to sigma(..cap alpha../sub H/) = 0.005, or a 0.3% error on sin /sup 2/theta/sub w/. The chiral polarization parameters, xi/sub A/, can also, be independently determined from I(E/sub A/, E/sub B/). 6 refs.

Research Organization:
State Univ. of New York, Binghamton (USA). Dept. of Physics
DOE Contract Number:
FG02-86ER40291
OSTI ID:
6207604
Report Number(s):
DOE/ER/40291-3; ON: DE89008229
Resource Relation:
Other Information: Portions of this document are illegible in microfiche products
Country of Publication:
United States
Language:
English