PhD Theses (Physics)

Browse

Browsing PhD Theses (Physics) by Subject "Belle Experiment"

Now showing 1 - 2 of 2
  • No Thumbnail Available
    Item
    Search for the Decay B0s → J/ψπ0 at Belle Experiment
    (2024) Kumar, Devender
    We report the first search for the decay B0s → J/ψπ0 using 121.4 fb−1 of data collected at Υ(5S) resonance state by the Belle detector at the KEKB asymmetric energy e+e− collider located at the High Energy Accelerator Research Organisation, Japan. We observe no signal and report an upper limit on the branching fraction, B(B0 s → J/ψπ0) of 1.21 × 10−5 at 90% confidence level. This result is the most stringent, improving the previous bound by two orders of magnitude.
  • No Thumbnail Available
    Item
    Search for the decay B_s^0 → π^0 π^0 at high luminosity electron-positron collider experiment
    (2023) Borah, Jyotimoi
    We report the results of the first search for the decay B_s^0 → π^0 π^0 using 121.4 fb^{-1} of data collected at the Υ(5S) resonance with the Belle detector at the KEKB asymmetric-energy electron-positron collider. We observe no signal and set a 90% confidence level upper limit of 7.7×10^{-6} on the B_s^0 → π^0 π^0 decay branching fraction. Our result constitutes the first stringent upper limit set by the Belle experiment for this decay channel.