Observation of the Annihilation Decay Mode B-0 -> K+K-

A search for the B-0 -> K+K- decay is performed using pp-collision data collected by LHCb. The data set corresponds to integrated luminosities of 1.0 and 2.0 fb(-1) at center-of-mass energies of 7 and 8 TeV, respectively. This decay is observed for the first time, with a significance of more than 5 standard deviations. The analysis also results in an improved measurement of the branching fraction for the B-s(0) -> pi(+)pi(-) decay. The measured branching fractions are B(B-0 -> K+K-) = (7.80 +/- 1.27 +/- 0.81 +/- 0.21) x 10(-8) and B(B-s(0) -> pi(+)p(-)) = (6.91 +/- 0.54 +/- 0.63 +/- 0.19 +/- 0.40) x 10(-7). The first uncertainty is statistical, the second is systematic, the third is due to the uncertainty on the B-0 -> K+pi(-) branching fraction used as a normalization. For the B-s(0) mode, the fourth accounts for the uncertainty on the ratio of the probabilities for b quarks to hadronize into B-s(0) and B-0 mesons.

Title: Observation of the Annihilation Decay Mode B-0 -> K+K-
Authors: Aaij, R.
Adeva, B.
Adinolfi, M
Keywords: B-S, Physical
Issue Date: 2017
Publisher: AMER PHYSICAL SOC, ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA
Citation: ISIKNOWLEDGE
Abstract: A search for the B-0 -> K+K- decay is performed using pp-collision data collected by LHCb. The data set corresponds to integrated luminosities of 1.0 and 2.0 fb(-1) at center-of-mass energies of 7 and 8 TeV, respectively. This decay is observed for the first time, with a significance of more than 5 standard deviations. The analysis also results in an improved measurement of the branching fraction for the B-s(0) -> pi(+)pi(-) decay. The measured branching fractions are B(B-0 -> K+K-) = (7.80 +/- 1.27 +/- 0.81 +/- 0.21) x 10(-8) and B(B-s(0) -> pi(+)p(-)) = (6.91 +/- 0.54 +/- 0.63 +/- 0.19 +/- 0.40) x 10(-7). The first uncertainty is statistical, the second is systematic, the third is due to the uncertainty on the B-0 -> K+pi(-) branching fraction used as a normalization. For the B-s(0) mode, the fourth accounts for the uncertainty on the ratio of the probabilities for b quarks to hadronize into B-s(0) and B-0 mesons.
Description: TNS06984 ; PHYSICAL REVIEW LETTERS Volume: 118 Issue: 8 Article Number: 081801 Published: FEB 21 2017
URI: http://repository.vnu.edu.vn/handle/VNU_123/28460
ISSN: 0031-9007
1079-7114
Appears in Collections:Bài báo của ĐHQGHN trong Web of Science

Nhận xét

Đăng nhận xét

Bài đăng phổ biến từ blog này

Nhu cầu đối với hoạt động công tác xã hội trong việc nâng cao kiến thức chăm sóc sức khỏe sinh sản vị thành niên ở nông thôn (Nghiên cứu trường hợp xã Lam Điền, huyện Chương Mỹ, thành phố Hà Nội)

Title:  Nhu cầu đối với hoạt động công tác xã hội trong việc nâng cao kiến thức chăm sóc sức khỏe sinh sản vị thành niên ở nông thôn (Nghiên cứu trường hợp xã Lam Điền, huyện Chương Mỹ, thành phố Hà Nội) Authors:  Đặng, Thùy Linh Keywords:  Công tác xã hội;Sức khỏe sinh sản Issue Date:  2016 Publisher:  H.: ĐHKHXH&NV Description:  97 tr. URI:  http://repository.vnu.edu.vn/handle/VNU_123/33919 Appears in Collections: Luận văn - Luận án (LIC)
Đọc thêm

Measurement of the isospin asymmetry in B → K (*)μ +μ - decays

The isospin asymmetries of B → K (*)μ +μ - decays and the partial branching fractions of B 0 → K 0μ +μ - and B +→ K *+μ +μ - are measured as a function of the di-muon mass squared q 2 using an integrated luminosity of 1.0fb -1 collected with the LHCb detector. The B → Kμ +μ - isospin asymmetry integrated over q 2 is negative, deviating from zero with over 4 σ significance. The B → K *μ +μ - decay measurements are consistent with the Standard Model prediction of negligible isospin asymmetry. The observation of the decay B 0 → K s 0μ +μ - is reported with 5.7 σ significance. Assuming that the branching fraction of B 0 → K 0μ +μ - is twice that of B 0 → K s 0μ +μ -, the branching fractions of B 0 → K 0μ +μ - and B → K *+μ +μ - are found to be (0.31 +0.07 -0.06) × 10 -6 and (1.16 ±0.19) × 10 -6, respectively. Title:  Measurement of the isospin asymmetry in B → K (*)μ +μ - decays Authors:  Aaij, Roel Abellán Beteta, C. Adametz, Aleksandra Keywords:  Hadron ...
Đọc thêm

Biomass estimation of Sonneratia caseolaris (l.) Engler at a coastal area of Hai Phong city (Vietnam) using ALOS-2 PALSAR imagery and GIS-based multi-layer perceptron neural networks

Hình ảnh
This study tested the use of machine learning techniques for the estimation of above-ground biomass (AGB) of Sonneratia caseolaris in a coastal area of Hai Phong city, Vietnam. We employed a GIS database and multi-layer perceptron neural networks (MLPNN) to build and verify an AGB model, drawing upon data from a survey of 1508 mangrove trees in 18 sampling plots and ALOS-2 PALSAR imagery. We assessed the model’s performance using root-mean-square error, mean absolute error, coefficient of determination (R2), and leave-one-out cross-validation. We also compared the model’s usability with four machine learning techniques: support vector regression, radial basis function neural networks, Gaussian process, and random forest. The MLPNN model performed well and outperformed the machine learning techniques. The MLPNN model-estimated AGB ranged between 2.78 and 298.95 Mg ha−1 (average = 55.8 Mg ha−1); below-ground biomass ranged between 4.06 and 436.47 Mg ha−1 (average = 81.47 M...
Đọc thêm