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Chang, T. T.

Publications and source records attributed to Chang, T. T..

69 records · Page 4
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DOE OSTI2023

Search for the semi-leptonic decays Λ c + → Λ π + π - e + ν e and Λ c + → p K S 0 π - e + ν e

We search for the semi-leptonic decays $Λ^+_c$ → Λπ + π - e + ν e and $Λ^+_c$ → p$K^0_S$π - e + ν e in a sample of 4.5 fb -1 of e + e - annihilation data collected in the center-of-mass energy region between 4.600 GeV and 4.699 GeV by the BESIII detector at the BEPCII. No significant signals are observed, and the upper limits on the decay branching fractions are set to be B($Λ^+_c$ → Λπ + π - e + ν e ) < 3.9 × 10 -4 and B($Λ^+_c$ → p$K^0_S$π - e + ν e ) < 3.3 × 10 -4 at the 90% confidence level, respectively

$Λ^+_c$↗
DOE OSTI2023

Search for an axion-like particle in radiative $J/ψ$ decays

We search for an axion-like particle (ALP) a through the process $\psi$(3686) → π + π – J/$\psi$, J/$\psi$ → γa, a → γγ in a data sample of (2.71 ± 0.01) x 10 9 $\psi$(3686) events collected by the BESIII detector. No significant ALP signal is observed over the expected background, and the upper limits on the branching fraction of the decay J/$\psi$ → γa and the ALP-photon coupling constant g aγγ are set at 95% confidence level in the mass range of 0.165 ≤ m a ≤ 2.84 GeV/c 2 . The limits on $\mathscr{B}$(J/$\psi$ → γa) range from 8.3 x 10 –8 to 1.8 x 10 –6 over the search region, and the constraints on the ALP-photon coupling are the most stringent to date for 0.165 ≤ m a ≤ 1.468 GeV/c 2 .

79 ASTRONOMY AND ASTROPHYSICS↗