Analysis of Ds Meson Decays at 4170 MeV in e+e- Collisions
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This study delves into the decay properties of the Ds meson at 4170 MeV in e+e- collisions, focusing on direct and indirect decay channels. Detailed selection criteria and results are presented, shedding light on the behavior of Ds meson decays.
Analysis of Ds Meson Decays at 4170 MeV in e+e- Collisions
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Presentation Transcript
Introduction • At the 4170, the g* was proven to decay mostly into D*D*, DD*, and DsDs* • Directly produced Ds Narrow MBC , theindirect Ds Wide MBC (gsmearing) Then plot • DSSelection • Loose cut on Ds Mbc,
Tag Selection direct Ds DS+DS- Events peak at the right Ds mass Indirect Ds Indirect Ds
DS+ fp, from DS+DS- yield = 40.3 ± 7.6 e = (41.0 ± 0.5)% # of Events / 2MeV Mbc (GeV) |DE| < 18.2 MeV (98.8% of the area under the DE distribution, i.e. 2.5s)
Thee+e- Ds+Ds- Cross Section DS+ fp, from DS+DS- DS+ fp, from DS+DS-* # of Events / 2MeV Mbc (GeV) Invariant Mass (GeV) yield = 40.3 ± 7.6 e = (41.0 ± 0.5)% yield = 1038.3 ± 34.6 e = (41.6 ± 0.5)% s(e+e- Ds+Ds-)/s(e+e- Ds+Ds-*) = ( 3.93 ± 0.76 )%
Ds+Ds- fp KKp # of Events / 2MeV Invariant Mass (GeV) |DE| < 18.2 MeV (98.8% of the area under the DE distribution, i.e. 2.5s)
Invariant Mass of Ds Tags from DATA K-p+p0 Total Number of Tags = (5067 ± 112) The signal region is defined ascontaining 98.8% (2.5 r.m.s widths) of the signal events with invariant mass below and above the Dspeak.
DsDs phipi dele 6mev Kkpi dele 6mev phipi dele 18.2mev Kkpi dele 18.2mev