Measurement of B0 ---> pi+ pi- pi+ pi- Decays and Search for B0 ---> rho0 rho0

Collaboration

Aug, 2008

6 pages

Published in:

e-Print:

DOI:

PDG:

{{\mathit B}^{0}}

\rightarrow

{{\mathit \rho}^{0}}{{\mathit \rho}^{0}}

Experiments:

View in:

Abstract: (arXiv)

We report on a search for the decay

B^0\to\rho^0\rho^0

and other charmless modes with a

\pi^+\pi^-\pi^+\pi^-

final state, including

B^0\to\rho^0\pi^+\pi^-

, non-resonant

B^0\to 4\pi^{\pm}

,

B^0\to\rho^0f_0(980)

,

B^0\to f_0(980)f_0(980)

and

B^0\to f_0(980)\pi^+\pi^-

. These results are obtained from a data sample containing 657 million

B \bar B

pairs collected with the Belle detector at the KEKB asymmetric-energy

e^+e^-

collider. We set an upper limit on

\mathcal{B}(B^0\to\rho^0\rho^0)

of

1.0\times 10^{-6}

at the 90% confidence level. From our

B^0\to\rho^0\rho^0

measurement and an isospin analysis, we determine the Cabibbo-Kobayashi-Maskawa phase

\phi_2

to be

91.7 \pm 14.9

degrees. We find excesses in

B^0\to\rho^0\pi^+\pi^-

and non-resonant

B^0\to 4\pi^{\pm}

with 1.3

\sigma

and 2.5

\sigma

significance with branching fractions less than

12.0 \times 10^{-6}

and

19.3 \times 10^{-6}

at the 90% confidence level, respectively.

Note:

References(0)

Figures(5)

Loading ...