Author: Tomohiko Tanabe
Publisher:
ISBN:
Category :
Languages : en
Pages : 248
Book Description
Search for Semileptonic Decays in the B Meson Into the [Lambda]+[subscript C] Baryon
Evidence for B Semileptonic Decays Into the Lambda_c Charm Baryon
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 16
Book Description
We present the first evidence for B semileptonic decays into the charmed baryon [Lambda]{sub c} based on 420 fb−1 of data collected at the [Upsilon](4S) resonance with the BABAR detector at the PEP-II ee− storage rings. Events are tagged by fully reconstructing one of the B mesons in a hadronic decay mode. We measure the relative branching fraction [Beta]({bar B} 2![Lambda]{sub c}+ Xl−{bar {nu}}{sub {ell}})/[Beta]({bar B} 2![Lambda]{sub c}+/{bar {Lambda}}{sub c}−X) = (3.2 ± 0.9{sub stat.} ± 0.9{sub syst.})%. The significance of the signal including the systematic uncertainty is 4.9 standard deviations.
Publisher:
ISBN:
Category :
Languages : en
Pages : 16
Book Description
We present the first evidence for B semileptonic decays into the charmed baryon [Lambda]{sub c} based on 420 fb−1 of data collected at the [Upsilon](4S) resonance with the BABAR detector at the PEP-II ee− storage rings. Events are tagged by fully reconstructing one of the B mesons in a hadronic decay mode. We measure the relative branching fraction [Beta]({bar B} 2![Lambda]{sub c}+ Xl−{bar {nu}}{sub {ell}})/[Beta]({bar B} 2![Lambda]{sub c}+/{bar {Lambda}}{sub c}−X) = (3.2 ± 0.9{sub stat.} ± 0.9{sub syst.})%. The significance of the signal including the systematic uncertainty is 4.9 standard deviations.
Searches for the Baryon- and Lepton-number Violating Decays $B^0\rightarrow\Lambda_c^ \ell^-$, $B^-\rightarrow\Lambda\ell^-$, and $B^-\rightarrow\bar{\Lambda}\ell^-$
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 10
Book Description
Searches for B mesons decaying to final states containing a baryon and a lepton are performed, where the baryon is either [Lambda]{sub c} or [Lambda] and the lepton is a muon or an electron. These decays violate both baryon and lepton number and would be a signature of physics beyond the standard model. No significant signal is observed in any of the decay modes, and upper limits in the range (3.2 - 520) x 10−8 are set on the branching fractions at the 90% confidence level.
Publisher:
ISBN:
Category :
Languages : en
Pages : 10
Book Description
Searches for B mesons decaying to final states containing a baryon and a lepton are performed, where the baryon is either [Lambda]{sub c} or [Lambda] and the lepton is a muon or an electron. These decays violate both baryon and lepton number and would be a signature of physics beyond the standard model. No significant signal is observed in any of the decay modes, and upper limits in the range (3.2 - 520) x 10−8 are set on the branching fractions at the 90% confidence level.
Study of Semileptonic Decays of B Mesons to Charmed Baryons
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 9
Book Description
Using data collected by the CLEO II detector at a center-of-mass energy on or near the [Upsilon](4S) resonance, we have determined the 90% confidence level upper limit [Beta]({bar B} 2![Lambda]{sub c}e− X)/[Beta]({bar B} 2!([Lambda]{sub c} or {bar [Lambda]}{sub c}−)X)
Publisher:
ISBN:
Category :
Languages : en
Pages : 9
Book Description
Using data collected by the CLEO II detector at a center-of-mass energy on or near the [Upsilon](4S) resonance, we have determined the 90% confidence level upper limit [Beta]({bar B} 2![Lambda]{sub c}e− X)/[Beta]({bar B} 2!([Lambda]{sub c} or {bar [Lambda]}{sub c}−)X)
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
Author: Robert Seddon
Publisher:
ISBN:
Category :
Languages : en
Pages :
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"--
Publisher:
ISBN:
Category :
Languages : en
Pages :
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"--
Semileptonic Decays of the B[subscript]c Meson in the Quark Meson Effective Theory
Observation of Inclusive B Meson Decays Into [lambda]+c̳ Baryons
Observation And Study of B Meson Decays with Lambda(C) Baryons with the BaBar Detector
Search for Bbar to Lambda_c+ X L- Nu Decays in Events with a Fully Reconstructed B Meson
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 7
Book Description
We present a search for semileptonic B decays to the charmed baryon [Lambda]{sub c} based on 420 fb−1 of data collected at the [Upsilon](4S) resonance with the BABAR detector at the PEP-II e+e− storage rings. By fully reconstructing the recoiling B in a hadronic decay mode, we reduce non-B backgrounds and determine the flavor of the signal B. We statistically correct the flavor for the effect of the B° mixing. We obtain a 90% confidence level upper limit of [Beta]({bar B} 2![Lambda]{sub c}+ Xl− {bar [nu]}{sub l})/[Beta]({bar B} 2![Lambda]{sub c}+ X)
Publisher:
ISBN:
Category :
Languages : en
Pages : 7
Book Description
We present a search for semileptonic B decays to the charmed baryon [Lambda]{sub c} based on 420 fb−1 of data collected at the [Upsilon](4S) resonance with the BABAR detector at the PEP-II e+e− storage rings. By fully reconstructing the recoiling B in a hadronic decay mode, we reduce non-B backgrounds and determine the flavor of the signal B. We statistically correct the flavor for the effect of the B° mixing. We obtain a 90% confidence level upper limit of [Beta]({bar B} 2![Lambda]{sub c}+ Xl− {bar [nu]}{sub l})/[Beta]({bar B} 2![Lambda]{sub c}+ X)
Semileptonic Decays of the B[subscript]c Meson in the Quark Meson Effective Theory [microform]
Author: Matthew A. (Matthew Alton) Nobes
Publisher: National Library of Canada = Bibliothèque nationale du Canada
ISBN: 9780612514348
Category : Lepton interactions
Languages : en
Pages : 174
Book Description
Publisher: National Library of Canada = Bibliothèque nationale du Canada
ISBN: 9780612514348
Category : Lepton interactions
Languages : en
Pages : 174
Book Description