Measurements of Time-Dependent CP-Asymmetry Parameters in B Meson Decays to \eta^{\prime} K^0 and of Branching Fractions of SU(3) Related Modes with BaBar Experiment at SLAC Metadata

Metadata describes a digital item, providing (if known) such information as creator, publisher, contents, size, relationship to other resources, and more. Metadata may also contain "preservation" components that help us to maintain the integrity of digital files over time.


  • Main Title Measurements of Time-Dependent CP-Asymmetry Parameters in B Meson Decays to \eta^{\prime} K^0 and of Branching Fractions of SU(3) Related Modes with BaBar Experiment at SLAC


  • Author: Biassoni, Pietro
    Creator Type: Personal
  • Author: U., /Milan
    Creator Type: Personal


  • Sponsor: United States. Department of Energy.
    Contributor Type: Organization


  • Name: Stanford Linear Accelerator Center
    Place of Publication: [Menlo Park, California]
    Additional Info: SLAC


  • Creation: 2009-01-22


  • English


  • Content Description: In this thesis work we have measured the following upper limits at 90% of confidence level, for B meson decays (in units of 10{sup -6}), using a statistics of 465.0 x 10{sup 6} B{bar B} pairs: {Beta}(B{sup 0} {yields} {eta}K{sup 0}) < 1.6 {Beta}(B{sup 0} {yields} {eta}{eta}) < 1.4 {Beta}(B{sup 0} {yields} {eta}{prime}{eta}{prime}) < 2.1 {Beta}(B{sup 0} {yields} {eta}{phi}) < 0.52 {Beta}(B{sup 0} {yields} {eta}{omega}) < 1.6 {Beta}(B{sup 0} {yields} {eta}{prime}{phi}) < 1.2 {Beta}(B{sup 0} {yields} {eta}{prime}{omega}) < 1.7 We have no observation of any decay mode, statistical significance for our measurements is in the range 1.3-3.5 standard deviation. We have a 3.5{sigma} evidence for B {yields} {eta}{omega} and a 3.1 {sigma} evidence for B {yields} {eta}{prime}{omega}. The absence of observation of the B{sup 0} {yields} {eta}K{sup 0} open an issue related to the large difference compared to the charged mode B{sup +} {yields} {eta}K{sup +} branching fraction, which is measured to be 3.7 {+-} 0.4 {+-} 0.1 [118]. Our results represent substantial improvements of the previous ones [109, 110, 111] and are consistent with theoretical predictions. All these results were presented at Flavor Physics and CP Violation (FPCP) 2008 Conference, that took place in Taipei, Taiwan. They will be soon included into a paper to be submitted to Physical Review D. For time-dependent analysis, we have reconstructed 1820 {+-} 48 flavor-tagged B{sup 0} {yields} {eta}{prime}K{sup 0} events, using the final BABAR statistic of 467.4 x 10{sup 6} B{bar B} pairs. We use these events to measure the time-dependent asymmetry parameters S and C. We find S = 0.59 {+-} 0.08 {+-} 0.02, and C = -0.06 {+-} 0.06 {+-} 0.02. A non-zero value of C would represent a directly CP non-conserving component in B{sup 0} {yields} {eta}{prime}K{sup 0}, while S would be equal to sin2{beta} measured in B{sup 0} {yields} J/{psi}K{sub s}{sup 0} [108], a mixing-decay interference effect, provided the decay is dominated by amplitudes of a single weak phase. The new measured value of S can be considered in agreement with the expectations of the 'Standard Model', inside the experimental and theoretical uncertainties. Inconsistency of our result for S with CP conservation (S = 0) has a significance of 7.1 standard deviations (statistical and systematics included). Our result for the direct-CP violation parameter C is 0.9 standard deviations from zero (statistical and systematics included). Our results are in agreement with the previous ones [18]. Despite the statistics is only 20% larger than the one used in previous measurement, we improved of 20% the error on S and of 14% the error on C. This error is the smaller ever achieved, by both BABAR and Belle, in Time-Dependent CP Violation Parameters measurement is a b {yields} s transition.
  • Physical Description: 418 pages


  • Keyword: Statistics Experiment-Hep, Experiment-Nucl,Hepex
  • Keyword: Decay
  • Keyword: Amplitudes
  • Keyword: B Mesons
  • STI Subject Categories: 43 Particle Accelerators
  • Keyword: Experiment-Hep, Experiment-Nucl,Hepex
  • Keyword: Asymmetry
  • Keyword: Physics
  • Keyword: Stanford Linear Accelerator Center
  • Keyword: Data


  • Name: Office of Scientific & Technical Information Technical Reports
    Code: OSTI


  • Name: UNT Libraries Government Documents Department
    Code: UNTGD

Resource Type

  • Thesis or Dissertation


  • Text


  • Report No.: SLAC-R-913
  • Grant Number: AC02-76SF00515
  • DOI: 10.2172/946451
  • Office of Scientific & Technical Information Report Number: 946451
  • Archival Resource Key: ark:/67531/metadc901765


  • Display Note: