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Bian, J. M.

Publications and source records attributed to Bian, J. M..

At least 19 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2018

Measurement of e + e - → $D\bar{D}$ cross sections at the ψ(3770) resonance

Here, we report new measurements of the cross sections for the production of $D\bar{D}$ final states at the ψ(3770) resonance. Our data sample consists of an integrated luminosity of 2.93 fb -1 of e + e - annihilation data produced by the BEPCII collider and collected and analyzed with the BESIII detector. We exclusively reconstruct three D 0 and six D + hadronic decay modes and use the ratio of the yield of fully reconstructed $D\bar{D}$ events ("double tags") to the yield of all reconstructed D or $\bar{D}$ mesons ("single tags") to determine the number of D 0 $\bar{D}$ 0 and D + D - events, benefiting from the cancellation of many systematic uncertainties. Combining these yields with an independent determination of the integrated luminosity of the data sample, we find the cross sections to be σ(e + e - → D 0 $\bar{D}$ 0 ) nb and σ(e + e - → D + D - ) = (2.830 ± 0.011 ± 0.026) nb, where the uncertainties are statistical and systematic, respectively.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2018

Study of the decays D + → η ( ' ) e + ν e

The charm semileptonic decays D + → ηe + v e and D + → η'e+v e are studied with a sample of e + e - collision data corresponding to an integrated luminosity of 2.93 fb -1 collected at $ \sqrt{s}=3.773 $ GeV with the BESIII detector. We measure the branching fractions for D+ → ηe+v e to be (10.74 ± 0.81 ± 0.51) x 10 -4 , and for D+ → → η'e+v e to be (1.91 ± 0.51 ± 0.13) x 10 -4 , where the uncertainties are statistical and systematic, respectively. In addition, we perform a measurement of the form factor in the decay D+ → ηe+v e . All the results are consistent with those obtained by the CLEO-c experiment.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗