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Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
Study of exclusive radiative B meson decays
Brandenburg1, Ershov, Gao
1Southern Methodist University, Dallas, Texas 75725, USA.
Physical Review Letters
|September 16, 2000
Summary
Researchers studied rare B meson decays to charmless mesons, measuring branching fractions for B to K(*) gamma decays and observing B to K(*)(2) gamma. CP asymmetry was also investigated in these B meson decays.
Area of Science:
- High Energy Physics
- Particle Physics
- Quantum Chromodynamics
Background:
- B meson decays provide insights into fundamental physics.
- Radiative decays are sensitive probes of New Physics beyond the Standard Model.
- Charmless decays test theoretical models of weak interactions.
Purpose of the Study:
- To measure branching fractions of exclusive, radiative B meson decays to charmless final states.
- To search for CP asymmetry in B to K(*) gamma decays.
- To investigate the presence of B to K(*)(2) gamma decays and set limits on other radiative decays.
Main Methods:
- Analysis of 9.7x10^6 BBbar decays collected by the CLEO detector.
- Event reconstruction using particle identification and kinematic criteria.
- Statistical analysis to determine branching fractions, CP asymmetry, and limits.
Main Results:
- Measured B(B0 to K(*0)(892)gamma) = (4.55 +/- 0.34)x10^-5.
- Measured B(B+ to K(*+)(892)gamma) = (3.76 +/- 0.28)x10^-5.
- Observed B to K(*)(2)(1430)gamma decays with B = (1.66 +/- 0.13)x10^-5.
- Measured CP asymmetry A(CP) = +0.08 +/- 0.13 +/- 0.03.
- Set a 90% C.L. limit: B(B to (rho/omega)gamma)/B(B to K(*)gamma) < 0.32.
Conclusions:
- Precise measurements of B to K(*) gamma branching fractions reported.
- First observation of B to K(*)(2) gamma decays.
- No evidence for B to rho/omega gamma decays, constraining their contribution.
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