Abe, K;
Adachi, I;
Aihara, H;
Arinstein, K;
Asano, Y;
Aushev, T;
Bakich, AM;
... Belle Collaboration; + view all
(2005)
Improved evidence for direct CP violation in B0 ->pi(+)pi(-) decays and model-independent constraints on phi(2).
PHYS REV LETT
, 95
(10)
, Article 101801. 10.1103/PhysRevLett.95.101801.
![]() Preview |
PDF
1308485.pdf Download (165kB) |
Abstract
We present a new measurement of the time-dependent CP-violating parameters in B-0 ->pi(+)pi(-) decays with 275x10(6) B (B) over bar pairs collected with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider operating at the Upsilon(4S) resonance. We find 666 +/- 43 B-0 ->pi(+)pi(-) events and measure the CP-violating parameters: S-pi pi=-0.67 +/- 0.16(stat)+/- 0.06(syst) and A(pi pi)=+0.56 +/- 0.12(stat)+/- 0.06(syst). We find evidence for large direct CP violation with a significance greater than 4 standard deviations for any S-pi pi value. Using isospin relations, we obtain 95.4% confidence intervals for the Cabibbo-Kobayashi-Maskawa quark-mixing matrix angle phi(2) of 0 degrees <phi(2)< 19 degrees and 71 degrees <phi(2)< 180 degrees.
Type: | Article |
---|---|
Title: | Improved evidence for direct CP violation in B0 ->pi(+)pi(-) decays and model-independent constraints on phi(2) |
Open access status: | An open access version is available from UCL Discovery |
DOI: | 10.1103/PhysRevLett.95.101801 |
Publisher version: | http://dx.doi.org/10.1103/PhysRevLett.95.101801 |
Language: | English |
Additional information: | © 2005 The American Physical Society |
Keywords: | B-DECAYS, BELLE, ASYMMETRIES |
UCL classification: | UCL UCL > Provost and Vice Provost Offices > UCL BEAMS UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Maths and Physical Sciences |
URI: | https://discovery.ucl.ac.uk/id/eprint/1308485 |




Archive Staff Only
![]() |
View Item |