2009 Fiscal Year Final Research Report
Precision Measurements of Flavor Changing Neutral Current Decays of B Mesons
| Project/Area Number |
18204019
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (A)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
Particle/Nuclear/Cosmic ray/Astro physics
|
|---|
| Research Institution | The University of Tokyo |
|---|
Principal Investigator |
AIHARA Hiroaki The University of Tokyo, 大学院・理学系研究科, 教授 (60167773)
|
|---|
| Co-Investigator(Renkei-kenkyūsha) |
IWASAKI Masako 東京大学, 大学院・理学系研究科, 講師 (70345172)
KAKUNO Hidekazu 東京大学, 素粒子物理国際研究センター, 助教 (70376698)
HAZUMI Masashi 大学共同利用機関法人高エネルギー加速器研究機構, 素粒子原子核研究所, 教授 (20263197)
HABA Junji 大学共同利用機関法人高エネルギー加速器研究機構, 素粒子原子核研究所, 教授 (60180923)
TSUBOYAMA Toru 大学共同利用機関法人高エネルギー加速器研究機構, 素粒子原子核研究所, 講師 (80188622)
|
|---|
| Project Period (FY) |
2006 – 2009
|
| Keywords | 素粒子物理 / Bファクトリー / B中間子 |
|---|
| Research Abstract |
We measured CP violating asymmetries in the neutral B meson decaying to KOsK+K-. It was based on a data sample containing 657 million B-antiB pairs. By employing the time-dependent Dalitz plot analysis to the BO decays with KOsK+K- final state, we successfully measured the CP-violating phases in each significant decay amplitude taking into account the interferences between them and resolved two-fold ambiguity in the weak phases that arises in quasi-two-body time-dependent CP analyses. Evidence for CP violation at a significance of 3.9σ is found in the BO->φKOs decay and the result is consistent with the Standard Model expectation. We also made a precise measurement of the branching fraction for a flavor-changing neutral current decay B→Xsl+l-, where Xs is a hadronic system containing an s-quark and l is an electron or a muon. The results are the most precise measurements to date.
|
-
-
[Journal Article] easurement of Time-Dependent CP-Violating Parameters in B^0 →K_S^0 K_S^0 Decays2008
Author(s)
H. Aihara, 4番目, J. Haba, 32番目, M. Hazumi, 36番目, M. Iwasaki, 46番目, T. Tsuboyama, 127番目, et al., 計145名
-
Journal Title
Physical Review Letters 100
Pages: 121601
Peer Reviewed
-
-
-
-
-
-
-
-
-
-
