Feynman diagrams for the decay of a neutral B meson into a rho and a K-star meson.

Corry’s Thesis Work

B0 meson decays to rho0 K*0, f0 K*0, and rho- K*+, including higher K* resonances

My Ph.D. research culminated in this paper, published in Physical Review D.  It has four and a half pages of authors because so many people are necessary to build and run a particle physics detector.

In plain English, I discovered several new decays of a short-lived particle (the B meson) that we created in high-energy collisions of electrons and anti-electrons.  These decays were theorized to exist, but had never before been observed.  By measuring the rate at which they occur, my work has helped theorists better understand the question of “where did all the antimatter go?” (see my layman’s discussion on the Big Bang and matter vs. antimatter.)


We present branching fraction measurements for the decays B0 -> rho0 K*0, B0 -> f0 K*0, and B0 -> rho- K*+, where K* is an S-wave (K pi)_0* or a K*(892) meson; we also measure B0 -> f0 K_2*(1430)^0. For the K*(892) channels, we report measurements of longitudinal polarization fractions (for rho final states) and direct CP-violation asymmetries. These results are obtained from a sample of (471.0 +/- 2.8) x 10^6 BBbar pairs collected with the BaBar detector at the PEP-II asymmetric-energy e+ e- collider at the SLAC National Accelerator Laboratory. We observe rho0 K*(892)^0, rho0 (K pi)_0^{*0}, f0 K*(892)^0, and rho- K*(892)+ with greater than 5 sigma significance, including systematics. We report first evidence for f0 (K pi)_0^{*0} and f0 K_2*(1430)^0, and place an upper limit on rho- (K pi)_0^{*+}. Our results in the K*(892) channels are consistent with no direct CP-violation.

Reference and link to the full article:

P. del Amo Sanchez et al. [BABAR Collaboration], Phys. Rev. D,85, 072005 (2012). [arXiv:1112.3896[hep-ex]]  “B0 meson decays to rho0 K*0, f0 K*0, and rho- K*+, including higher K* resonances.”

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