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Hu, J. F.

Publications and source records attributed to Hu, J. F..

15 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2019

Study of electromagnetic Dalitz decays χ c J → μ + μ - J / ψ

Using 4.48 × 10 8 ψ (3686) events collected with the BESIII detector, we search for the decays χ cJ → μ + μ – J/ψ through the radiative decays ψ(3686) → γχ cJ , where J = 0,1,2. The decays χ c1,2 → μ + μ – J/ψ are observed, and the corresponding branching fractions are measured to be B(χ c1 → μ + μ – J/ψ) = (2.51 ± 0.18 ± 0.20) × 10 –4 and B(χ c2 → μ + μ – J/ψ) = (2.33 ± 0.18 ± 0.29) × 10 –4 , where the first uncertainty is statistical and the second one systematic. No significant χ c0 → μ + μ – J/ψ decay is observed, and the upper limit on the branching fraction is determined to be 2.0×10 –5 at 90% confidence level. Furthermore, we present a study of dimuon invariant mass dependent transition form factor for the decays χ c1,2 → μ + μ – J/ψ.

astronomy & astrophysics↗
DOE OSTI2016

Measurements of the center-of-mass energies at BESIII via the di-muon process

From 2011 to 2014, the BESIII experiment collected about 5 fb -1 data at center-of-mass energies around 4 GeV for the studies of the charmonium-like and higher excited charmonium states. By analyzing the di-muon process e + e - → γ ISR/FSR μ + μ - , the center-of-mass energies of the data samples are measured with a precision of 0.8 MeV. The center-of-mass energy is found to be stable for most of the time during data taking.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2015

Study of dynamics of D 0 → K – e + ν e and D 0 → π – e + ν e decays

Here, in an analysis of a 2.92 fb –1 data sample taken at 3.773 GeV with the BESIII detector operated at the BEPCII collider, we measure the absolute decay branching fractions to be B(D 0 → K – e + ν e ) = (3.505 ± 0.014 ± 0.033)% and B(D 0 → π – e + ν e ) = (0.295 ± 0.004 ± 0.003)%. From a study of the differential decay rates we obtain the products of hadronic form factor and the magnitude of the CKM matrix element $f$ $^{K}_{+}$(0)|V cs | = 0.7172 ± 0.0025 ± 0.0035 and $f$ $^{π}_{+}$(0)|V cd | = 0.1435 ± 0.0018 ± 0.0009.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗