English

Large forward-backward asymmetry in B --> K mu+ mu- from new physics tensor operators

High Energy Physics - Phenomenology 2010-04-15 v1

Abstract

We study the constraints on possible new physics contribution to the forward-backward asymmetry of muons, A_{FB}(q^2), in B --> K mu+ mu-. New physics in the form of vector/axial-vector operators does not contribute to A_{FB}(q^2) whereas new physics in the form of scalar/pseudoscalar operators can enhance A_{FB}(q^2) only by a few per cent. However new physics the form of tensor operators can take the peak value of A_{FB}(q^2) to as high as 40% near the high-q^2 end point. In addition, if both scalar/pseudoscalar and tensor operators are present, then A_{FB}(q^2) can be more than 15% for the entire high-q^2 region q^2 > 15 GeV^2. The observation of significant A_{FB} would imply the presence of new physics tensor operators, whereas its q^2 dependence could further indicate the presence of new scalar/pseudoscalar physics.

Cite

@article{arxiv.0810.3779,
  title  = {Large forward-backward asymmetry in B --> K mu+ mu- from new physics tensor operators},
  author = {Ashutosh Kumar Alok and Amol Dighe and S. Uma Sankar},
  journal= {arXiv preprint arXiv:0810.3779},
  year   = {2010}
}

Comments

19 pages, 5 figures

R2 v1 2026-06-21T11:33:17.369Z