Search for a light Higgs resonance in radiative decays of the ϒ(1S) with a charm tag

Abstract

A search is presented for the decay ϒ(1S)→γA[superscript 0], A[superscript 0] → c[bar over c], where A[superscript 0] is a candidate for the CP-odd Higgs boson of the next-to-minimal supersymmetric standard model. The search is based on data collected with the BABAR detector at the ϒ(2S) resonance. A sample of ϒ(1S) mesons is selected via the decay ϒ(2S) → π[superscript +]π[superscript -]ϒ(1S). The A[superscript 0] → c[bar over c] decay is identified through the reconstruction of hadronic D[superscript 0], D[superscript +], and D[superscript *](2010)[superscript +] meson decays. No significant signal is observed. The measured 90% confidence-level upper limits on the product branching fraction B(ϒ(1S) → γA[superscript 0]) × B(A[superscript 0] → c[bar over c]) range from 7.4 × 10[superscript -5] to 2.4 × 10[superscript -3] for A[superscript 0] masses from 4.00 to 8.95 GeV/c[superscript 2] and 9.10 to 9.25 GeV/c[superscript 2], where the region between 8.95 and 9.10 GeV/c[superscript 2] is excluded because of background from ϒ(2S) → γχ[subscript bJ](1P), χ[subscript bJ](1P) → γϒ(1S) decays.