CP violation in single top quark production and decay via p{bar p}{r_arrow}t{bar b}+X{r_arrow}W{sup +}b{bar b}+X within the MSSM: A possible application for measuring arg(A{sub t}) at hadron colliders
- Department of Physics, University of California at Riverside, Riverside, California 92521 (United States)
- Theory Group, Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606 (United States)
- Physics Department, Brookhaven National Laboratory, Upton, New York 11973 (United States)
CP-nonconserving effects in the reaction p{bar p}{r_arrow}t{bar b}+X{r_arrow}W{sup +}b{bar b}+X, driven by the supersymmetric CP-odd phase of the top squark trilinear soft breaking term arg(A{sub t}), are studied. We discuss the CP-nonconserving effects in both production and the associated decay amplitudes of the top quark. We find that, within a plausible low energy scenario of the MSSM and keeping the neutron electric dipole moment below its current limit, a CP-violating cross-section asymmetry as large as 2{minus}3{percent} can arise if some of the parameters lie in a favorable range. A partial rate asymmetry originating only in the top quark decay t{r_arrow}W{sup +}b is found to be, in general, below the 0.1{percent} level which is somewhat smaller than previous claims. For a low tan{beta} of order one the decay asymmetry can reach at the most {approximately}0.3{percent}. This (few) percent level overall CP-violating signal in p{bar p}{r_arrow}t{bar b}+X{r_arrow}W{sup +}b{bar b}+X might be within the reach of the future 2(4) TeV p{bar p} Fermilab Tevatron collider that may be able to produce {approximately}10000 ({approximately}30000) such t{bar b} events with an integrated luminosity of 30 fb{sup {minus}1}. In particular, it may be used to place an upper bound on arg(A{sub t}) if indeed arg({mu}){r_arrow}0, as implied from the present experimental limit on the neutron electric dipole moment. The partial rate asymmetry in the top quark decay ({approximately}few{times}10{sup {minus}3}) may also be within the reach of the CERN LHC with {approximately}10{sup 7} pairs of t{bar t} produced, provided detector systematics are sufficiently small. We also show that if the GUT scale universality of the soft breaking trilinear A terms is relaxed, then the phases associated with arg(A{sub u}) and arg(A{sub d}) can take values up to {approximately}few{times}10{sup {minus}1} even with squarks and gluino masses of several hundred GeV{close_quote}s without contradicting the experimental limit on the neutron electric dipole moment. {copyright} {ital 1997} {ital The American Physical Society}
- OSTI ID:
- 567113
- Journal Information:
- Physical Review, D, Vol. 57, Issue 3; Other Information: PBD: Feb 1998
- Country of Publication:
- United States
- Language:
- English
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