Study of Rare B-Meson Decays Related to the CP Observable Sin(2[beta] + [gamma]) at the BABAR Experiment

Study of Rare B-Meson Decays Related to the CP Observable Sin(2[beta] + [gamma]) at the BABAR Experiment PDF Author: Toyoko Jennifer Orimoto
Publisher:
ISBN:
Category :
Languages : en
Pages : 476

Get Book Here

Book Description

Study of Rare B-Meson Decays Related to the CP Observable Sin(2[beta] + [gamma]) at the BABAR Experiment

Study of Rare B-Meson Decays Related to the CP Observable Sin(2[beta] + [gamma]) at the BABAR Experiment PDF Author: Toyoko Jennifer Orimoto
Publisher:
ISBN:
Category :
Languages : en
Pages : 476

Get Book Here

Book Description


Study of Rare B-Meson Decays Related to the CPObservable Sin(2beta+gamma) at the BABAR Experiment

Study of Rare B-Meson Decays Related to the CPObservable Sin(2beta+gamma) at the BABAR Experiment PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 237

Get Book Here

Book Description
This study reports the observation of the decays B02!$*+\atop{s}$[pi]- and B02!(*)-K+ in a sample of 230 x 106 Y(4S) 2!B$\bar{B}$ events collected with the BABAR detector at the PEP-II asymmetric-energy e+e- storage ring, located at the Stanford Linear Accelerator Center. The branching fractions [beta](B0 2!D$+\atop{S}$[pi]- ) = (1.3 ± 0.3 (stat) ± 0.2 (syst)) x 10-5, [beta](B0 2!D$+\atop{S}$K+) = (2.5 ± 0.4 (stat) ± 0.4 (syst)) x 10-5, [beta](B02!$*+\atop{s}$[pi]- ) = (2.8 ± 0.6 (stat) ± 0.5 (syst)) x 10-5, and [beta](B02!(*)-K+) = (2.0 ± 0.5 (stat) ± 0.4 (syst)) x 10-5 are measured. The significance of the measurements to differ from zero are 5, 9, 6, and 5 standard deviations, respectively. This is a first observation of the decaysB+2!$*+\atop{s}$[pi]- and B02!(*)-K+. These results may potentially be useful in determining the CP asymmetry parameter sin(2[beta] + [gamma]) in the decays B02!$*+\atop{s}$[pi]-

Studying B --] S Gamma at BABAR Using a Fully Inclusive Method

Studying B --] S Gamma at BABAR Using a Fully Inclusive Method PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :

Get Book Here

Book Description
The b [yields] s[gamma] decay represents a possible electromagnetic ''loop'' penguin decay of the B meson. This FCNC process is of high theoretical interest because various scenarios of new physics are expected to have contributions at the same (one loop) level as the Standard Model. The large sample of B[bar B] meson decays collected by the BaBar experiment makes a precision measurement of this rare decay possible. In conjunction with Standard Model predictions at the 10% level, it brings new physics effects into the realm of detection--or seriously constrains models that could predict them. A fully inclusive technique is presented to study the b [yields] s[gamma] transition as a function of photon energy, using 88.5 [+-] 1.0 x 10[sup 6] B[bar B] meson decays collected by the BaBar experiment in the years 2000 to 2002. The expected statistical and systematic uncertainties have been fully determined which enables first comparisons with theoretical predictions and other experimental results. It also lays the basis for the determination of the inclusive branching fraction [Beta](B [yields] X[sub s][gamma]) and the measurement of the photon energy spectrum.

The Search for Rare Non-hadronic B-meson Decays with Final-state Neutrinos Using the BaBar Detector

The Search for Rare Non-hadronic B-meson Decays with Final-state Neutrinos Using the BaBar Detector PDF Author: Dana Lindemann
Publisher:
ISBN:
Category :
Languages : en
Pages :

Get Book Here

Book Description
"This thesis presents the searches for two rare B meson decays: the radiative leptonic decay B+ -> l+ nu gamma (l = e, mu) and the flavor-changing neutral current B -> K(*) nu nubar. These searches use the full dataset collected by the BaBar experiment, which corresponds to almost 500 million BB pairs. After fully reconstructing the hadronic decay of one of the B mesons in Upsilon(4S) -> BB decays, evidence of B+ -> l+ nu gamma or B -> K(*) nu nubar is looked for in the rest of the event. No significant evidence of either signal decay is observed. Model-independent branching-fraction upper limits are set at BR(B ->e nu gamma)17 x10 {-6}, BR(B -mu nu gamma)24 x10 {-6}, and BR(B -l nu gamma)15.6 x10 {-6}, all at the 90% confidence level. These are currently the most stringent published upper limits for B+ - l+ nu gamma. In addition, branching-fraction upper limits are set at BR(B -> K+ nu nubar)3.7 x10 {-5}, BR(B - K0 nu nubar)8.0 x10 {-5}, BR(B - K*+ nu nubar)11.5 x10 {-5}, and BR(B - K*0 nu nubar)9.2 x10 {-5}, all at the 90% confidence level. For additional sensitivity to New Physics contributions, partial B - K(*) nu nubar branching-fraction upper limits are also determined over the full kinematic range." --

Study of Hadronic and Rare B Decays in BABAR.

Study of Hadronic and Rare B Decays in BABAR. PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 5

Get Book Here

Book Description
We present results from BaBar experiment for the measurement of inclusive and exclusive branching fractions of B mesons into final states containing J/[psi], [psi](2S) and [chi]c. The contributions of CP even and odd amplitudes in the decay B° 2!J/[psi]K*° are determined from an angular analysis. We report the measurements of the branching ratios B° 2!D* D*− and D* D*− K{sub S}°, and the study of exclusive two-body and quasi-two-body charmless decays. The branching fraction of the decay B° 2!K*°[gamma] has been determined and the corresponding CP asymmetry has been measured.

Rare And Radiative B Meson Decays From the BaBar Experiment

Rare And Radiative B Meson Decays From the BaBar Experiment PDF Author: J. Stelzer
Publisher:
ISBN:
Category :
Languages : en
Pages : 5

Get Book Here

Book Description
Since its start in 1999 the BABAR experiment has collected a vast amount of data. Electron-positron collisions at the energy of the {Upsilon}(4S) resonance have produced about 240 million coherent B{sup 0}{bar B}{sup 0} and B{sup +}B{sup -} pairs, opening the doors for exploration of rare B meson decays. An overview of the electroweak penguin physics program of BABAR is given, the analysis of two specific decays is presented in detail.

Rare B Meson Decays With Omega Mesons

Rare B Meson Decays With Omega Mesons PDF Author: Lei Zhang
Publisher:
ISBN:
Category :
Languages : en
Pages : 184

Get Book Here

Book Description
Rare charmless hadronic B decays are particularly interesting because of their importance in understanding the CP violation, which is essential to explain the matter-antimatter asymmetry in our universe, and of their roles in testing the ''effective'' theory of B physics. The study has been done with the BABAR experiment, which is mainly designed for the study of CP violation in the decays of neutral B mesons, and secondarily for rare processes that become accessible with the high luminosity of the PEP-II B Factory. In a sample of 89 million produced B{bar B} pairs on the BABAR experiment, we observed the decays B{sup 0} {yields} {omega}K{sup 0} and B{sup +} {yields} {omega}{rho}{sup +} for the first time, made more precise measurements for B{sup +} {yields} {omega}h{sup +} and reported tighter upper limits for B {yields} {omega}K* and B{sup 0} {yields} {omega}{rho}{sup 0}.

Study of Rare B Meson Decays Related to the CKM Angle Beta at BaBar

Study of Rare B Meson Decays Related to the CKM Angle Beta at BaBar PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 182

Get Book Here

Book Description


Search for the Rare Decay of a B Meson Into a Lambda Baryon, Proton and Neutrino-antineutrino Pair at the BABAR and Belle II Experiments

Search for the Rare Decay of a B Meson Into a Lambda Baryon, Proton and Neutrino-antineutrino Pair at the BABAR and Belle II Experiments PDF Author: Robert Seddon
Publisher:
ISBN:
Category :
Languages : en
Pages :

Get Book Here

Book Description
"We present two analyses of the rare B- -> Lambda pbar nu nubar decay. Within the Standard Model, the process B- -> Lambda pbar nu nubar is permitted but highly suppressed, with an expected branching fraction of (7.9 +/- 1.9) x 10^-7. This rarity makes it a sensitive probe for the existence of new physics, which may be discoverable in the form of a higher than predicted branching fraction.The first analysis is conducted on data collected at the BABAR experiment, which ran from 1999-2008. BABAR collected 433 fb^-1 of integrated luminosity at the Upsilon(4S) resonance; Upsilon(4S) decays almost exclusively into B-Bbar pairs, and this analysis uses hadronic tag reconstruction to fully reconstruct one of the B-mesons in this pair. The search for B- -> Lambda pbar nu nubar is then conducted among the decay products of the second, unreconstructed B-meson. Using both real data and Monte Carlo simulations, we develop and implement a signal selection that selects candidates conforming to the expected characteristics of B- -> Lambda pbar nu nubar decays. The result of the analysis is an upper limit on the branching fraction at the 90% confidence level of 3.02 x 10^-5. This is the world's first experimental result in the search for B- -> Lambda pbar nu nubar decays.The second analysis is conducted on Monte Carlo simulations of data that will be collected at Belle II, the world's only next-generation B-meson facility. Over its lifetime Belle II will collect 50 ab^-1 of data, approximately 100 times that of BABAR. This increase in data, along with more capable hardware and software, should allow Belle II to search for B- -> Lambda pbar nu nubar decays with greater sensitivity than BABAR. Using a simulated dataset equivalent in size to that used in our BABAR study, we employ Full Event Interpretation to fully reconstruct the decay of one B-meson in each B-Bbar pair, and conduct our signal selection in the remainder of the data. The result of the analysis is a predicted upper limit on the branching fraction at the 90% confidence level of 1.2 x 10^-4. A comparison of the Belle II and BABAR results highlights several areas where Belle II will need to improve in order to make best use of its projected dataset"--

Rare Decays And Exotic States With BaBar

Rare Decays And Exotic States With BaBar PDF Author: S. H. Robertson
Publisher:
ISBN:
Category :
Languages : en
Pages : 12

Get Book Here

Book Description
Results from the BABAR experiment are presented for searches for several rare FCNC B and D meson decays, including the modes B{sup 0} {yields} {ell}{sup +}{ell}{sup -} and D{sup 0} {yields} {ell}{sup +}{ell}{sup -}, B {yields} ({rho}, {omega}){gamma} and B{sup +} {yields} (K, {pi}){sup +}{nu}{bar {nu}}. Limits on lepton flavor violation in neutrino-less {tau} decays are also discussed. Finally, results of BABAR searches for the strange pentaquark states {Theta}{sup +}(1540), {Xi}{sup --}(1860) and {Xi}{sup 0}(1860) are summarized.