ISSN - 15507998, Physical Review D - Particles, Fields, Gravitation and Cosmology, 2014, vol. 90, p. -
Search for the weak decays J/ψ → Ds (∗)- e+νe+ c. c.
© 2014 American Physical Society. Using a sample of 2.25×108 J/ψ events collected with the BESIII detector at the BEPCII collider, we search for the J/ψ semileptonic weak decay J/ψ→Ds-e+νe+c.c. with a much higher sensitivity than previous searches. We also perform the first search for J/ψ→Ds∗-e+νe+c.c. No significant excess of a signal above background is observed in either channel. At the 90% confidence level, the upper limits are determined to be B(J/ψ→Ds-e+νe+c.c.)<1.3×10-6 and B(J/ψ→Ds∗-e+νe+c.c.)<1.8×10-6, respectively. Both are consistent with Standard Model predictions.