Leptophobic Z0 boson and parity-violating eD scattering

Martı́n González-Alonso and Michael J. Ramsey-Musolf Department of Physics, University of Wisconsin, Madison, Wisconsin 53706, USA Kellogg Radiation Laboratory, California Institute of Technology, Pasadena, California 91125, USA (Received 25 December 2012; published 14 March 2013) We study the impact of a leptophobic Z0 gauge boson on the C1q and C2q parameters that describe the low-energy, parity-violating electron-quark neutral current interaction. We complement previous work by including the penguin-like vertex corrections, thereby completing the analysis of one-loop calculation up to Oðmq0=M Z0 Þ terms. We analyze the sensitivity of these probes to the different couplings Z0 uq (q 1⁄4 u, c, t) and Z0 dq (q 1⁄4 d, s, b) in a model-independent way that can be applied to any specific Z0 scenario. We show that constraints from neutral kaon and heavy flavor studies preclude significant contributions from flavor nondiagonal couplings except for those involving top quarks. We apply our results to a light Z0 with flavor diagonal couplings to up or down quarks, a scenario proposed in the literature to explain the CDF W plus dijet anomaly. We find that such a particle would not affect the C1q coefficients, but it would have a sizable impact on C2q couplings that can be probed by future measurements of parity-violating deep inelastic scattering of polarized electrons off of deuterium.