Semileptonic Decays of Charged D Meson Going to Eta-lepton-neutrino with Generic Reconstruction of Fully Hadronic Charged D Meson and Neutral D Meson Decays
Semileptonic Decays of Charged D Meson Going to Eta-lepton-neutrino with Generic Reconstruction of Fully Hadronic Charged D Meson and Neutral D Meson Decays

Author: Richard Carl Gray

Publisher:

Published: 2008

Total Pages: 202

ISBN-13: 9781109020489

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We study the semileptonic decays D + & rarr; eta'e+nu and D+ & rarr; etae+nu using 818 pb-1 of e+ e- collisions recorded by the CLEO-c detector located at the Cornell Electron Storage Ring. We employ a technique that uses the detector hermeticity to reconstruct the neutrino as missing energy and momentum. We improve the neutrino resolution by developing a generic algorithm to reconstruct the non-signal D, and constrain systematic uncertainties in the efficiency by using the algorithm to measure the branching fractions of D+ and D0 hadronic decays. We observe and measure the branching fractions of 67 hadronic decays, 32 of which are not listed in the PDG 2008. We find B (D+ & rarr; eta'e +nu) = (2.16 +/- 0.53 +/- 0.05 +/- 0.05) x 10-4 and B (D+ & rarr; etae +nu) = (11.7 +/- 0.98 +/- 0.34 +/- 0.26) x 10-4. Among the 67 D hadronic branching fractions observed in this analysis, we discover the decay B (D+ & rarr; pi+etaeta) = (0.34 +/- 0.06 +/- 0.032)% which is unexpectedly large considering the limited phase space available to the decay.

Leptonic Decays of the Charged B Meson
Leptonic Decays of the Charged B Meson

Author: Luke Andrew Corwin

Publisher:

Published: 2008

Total Pages: 148

ISBN-13:

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Abstract: We present a search for the decay of the charged B meson into a charged lepton and a neutrino 458.9 million Upsilon(4S) decays recorded with the Babar detector at the SLAC PEP-II B-Factory. A sample of events with one reconstructed exclusive semileptonic B decay is selected, and in the recoil a search for the signal decay is performed. The tau lepton is identified in decays to an electron and two neutrinos; a muon and two neutrinos; a charged pion and a neutrino; or a charged pion, a neutral pion, and a neutrino. The analysis strategy and the statistical procedure is set up for branching fraction extraction or upper limit determination. We determine from the data set a preliminary measurement of the branching fraction a charged B decaying to a tau lepton and a neutrino = (1.8 " 0.8 " 0.1)E-4, which excludes zero at 2.4 standard deviations. We extract the B meson decay constant = 255 " 58 MeV. Combination with the hadronically tagged measurement yields (1.8 " 0.6)E-4. We also set preliminary limits on the branching fraction of charged B decaying to an electron and a neutrino at 7.7E-6 and the charged B decaying to a muon and a neutrino at 11E-6. The limits are at the 90% confidence level.

Semileptonic Decays D Exp(+) -> Eta Exp(') L Exp(+) V With Generic Reconstruction Of Fully Hadronic D Exp(+) And D Exp(0) Decays
Semileptonic Decays D Exp(+) -> Eta Exp(') L Exp(+) V With Generic Reconstruction Of Fully Hadronic D Exp(+) And D Exp(0) Decays

Author: Richard Carl Gray

Publisher:

Published: 2009

Total Pages: 0

ISBN-13:

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We study the semileptonic decays D+ [RIGHTWARDS ARROW] [eta] e+ [nu] and D+ [RIGHTWARDS ARROW] [eta]e+ [nu] using 818 pb[-]1 of e+ e[-] collisions recorded by the CLEO-c detector located at the Cornell Electron Storage Ring. We employ a technique that uses the detector hermeticity to reconstruct the neutrino as missing energy and momentum. We improve the neutrino resolution by developing a generic algorithm to reconstruct the non-signal D, and constrain systematic uncertainties in the efficiency by using the algorithm to measure the branching fractions of D+ and D0 hadronic decays. We observe and measure the branching fractions of 67 hadronic decays, 32 of which are not listed in the PDG 2008. We find B(D+ [RIGHTWARDS ARROW] [eta] e+ [nu]) = (2.16 ± 0.53 ± 0.05 ± 0.05) x 10[-]4 and B(D+ [RIGHTWARDS ARROW] [eta]e+ [nu]) = (11.7 ± 0.98 ± 0.34 ± 0.26) x 10[-]4 . Among the 67 D hadronic branching fractions observed in this analysis, we discover the decay B(D+ [RIGHTWARDS ARROW] [pi]+ [eta][eta]) = (0.34 ± 0.06 ± 0.032)% which is unexpectedly large considering the limited phase space available to the decay.

Recent Results on D Meson Decays from the MARK III.
Recent Results on D Meson Decays from the MARK III.

Author:

Publisher:

Published: 1985

Total Pages:

ISBN-13:

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The MARK III Collaboration recently completed the analysis of a number of decay modes of charged and neutral D mesons produced in electron-positron collisions near the peak of the psi(3770) resonance at SLAC's SPEAR storage ring. The mesons were produced nearly at rest in pairs, either DD− or D° anti D°, at a center-of-mass energy below the threshold for DD production. The unique kinematics of the production allow us to isolate the charmed meson signal clearly and unambiguously. The data were collected with the MARK III Spectrometer, a large solid angle magnetic detector. Our data sample corresponds to an integrated luminosity of approximately 9.3 inverse picobarns. New results will be presented on the absolute branching ratios of D mesons into hadronic final states, branching ratios for three body decays via pseudoscalar-vector intermediate states, and branching ratios for Cabibbo allowed and Cabibbo suppressed decays. Inclusive and exclusive branching ratios for the semi-leptonic decays of D mesons will be presented, as well as the first measurement of the vector form factor in the decay D° .-->. K−e, nu, evidence for interference in D+ decays, and new information on the contributions of W exchange diagrams to D° decays.

Search for Neutral D Meson Mixing Using Semileptonic Decays
Search for Neutral D Meson Mixing Using Semileptonic Decays

Author: Kevin T. Flood

Publisher:

Published: 2006

Total Pages: 178

ISBN-13:

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Based on a 87 fb{sup -1} dataset, a search for D{sup 0}-{bar D}{sup 0} mixing is made using the semileptonic decay modes D*{sup +} {yields} {pi}{sup +} D{sup 0}, D{sup 0} {yields} [K/K*]e{nu} (+c.c.) at the B-Factory facility at the Stanford Linear Accelerator Center. These modes offer unambiguous initial and final-state charm flavor tags, and allow the combined use of the D{sup 0} lifetime and D*{sup +}-D{sup 0} mass difference ({Delta}M) in a global likelihood fit. The high-statistics sample of reconstructed unmixed semileptonic D{sup 0} decays is used to model both the {Delta}M distribution and the time-dependence of mixed events directly from the data. Neural networks are used both to select events and to fully reconstruct the D{sup 0}. A result consistent with no charm mixing has been obtained, R{sub mix}