A Study of Time-dependent CP-violating Asymmetries in B0-]J/psiK0S and B0-]psi(2S)K0S Decays

A Study of Time-dependent CP-violating Asymmetries in B0-]J/psiK0S and B0-]psi(2S)K0S Decays PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 5

Book Description
We present a preliminary measurement of time-dependent CP-violating asymmetries in B° → J/[psi] K{sub S}° and B° → [psi](2S)K{sub S}° decays recorded by the BABAR detector at the PEP-II asymmetric-energy B Factory at SLAC. The data sample consists of 9.0 fb−1 collected at the [Upsilon](4S) resonance and 0.8 fb−1 off-resonance. One of the neutral B mesons, produced in pairs at the [Upsilon](4S), is fully reconstructed. The flavor of the other neutral B meson is tagged at the time of its decay, mainly with the charge of identified leptons and kaons. A neural network tagging algorithm is used to recover events without a clear lepton or kaon tag. The time difference between the decays is determined by measuring the distance between the decay vertices. Wrong-tag probabilities and the time resolution function are measured with samples of fully-reconstructed semileptonic and hadronic neutral B final states. The value of the asymmetry amplitude, sin2[beta], is determined from a maximum likelihood fit to the time distribution of 120 tagged B° → J/[psi] K{sub S}° and B° → [psi](2S) K{sub S}° candidates to be sin2[beta] = 0.12 ± 0.37(stat) ± 0.09(syst) (preliminary).

A Study of Time-Dependent CP-Violating Asymmetries and Flavor Oscillations in Neutral B Decays at the Upsilon(4S).

A Study of Time-Dependent CP-Violating Asymmetries and Flavor Oscillations in Neutral B Decays at the Upsilon(4S). PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :

Book Description
We present a measurement of time-dependent CP-violating asymmetries in neutral B meson decays collected with the BABAR detector at the PEP-II asymmetric-energy B Factory at the Stanford Linear Accelerator Center. The data sample consists of 29.7 fb[sup -1] recorded at the[Upsilon](4S) resonance and 3.9 fb[sup -1] off-resonance. One of the neutral B mesons, which are produced in pairs at the[Upsilon](4S), is fully reconstructed in the CP decay modes J/[psi] K[sub S][sup 0], [psi](2S) K[sub S][sup 0], [chi][sub c1] K[sub S][sup 0], J/[psi] K*[sup 0] (K*[sup 0][yields] K[sub S][sup 0][pi][sup 0]) and J/[psi] K[sub L][sup 0], or in flavor-eigenstate modes involving D(*)[pi]/[rho]/[sub 1] and J/[psi] K*[sup 0] (K*[sup 0][yields] K[sup+][pi][sup -]). The flavor of the other neutral B meson is tagged at the time of its decay, mainly with the charge of identified leptons and kaons. A neural network tagging algorithm is used to recover events without a clear lepton or kaon tag. The proper time elapsed between the decays is determined by measuring the distance between the decay vertices. Wrong-tag probabilities, the time-difference resolution function, and the B[sup 0]-[bar B][sup 0] oscillation frequency[Delta]m[sub d]are measured with a sample of about 6350 fully-reconstructed B[sup 0] decays in hadronic flavor-eigenstate modes. A maximum-likelihood fit to this flavor eigenstate sample finds[Delta]m[sub d]= 0.516[+-] 0.016 (stat)[+-] 0.010 (syst) ps[sup -1]. The value of the asymmetry amplitude sin2[beta] is determined from a simultaneous maximum-likelihood fit to the time-difference distribution of the flavor-eigenstate sample and about 642 tagged B[sup 0] decays in the CP-eigenstate modes. We find sin2[beta]= 0.59[+-] 0.14 (stat)[+-] 0.05 (syst), demonstrating that CP violation exists in the neutral B meson system. We also determine the value of the CP violation parameter[lambda]= 0.93[+-] 0.09 (stat)[+-] 0.03 (syst), which is consistent with the expectation of[lambda]= 1 for no direct CP violation.

Пора кончать!

Пора кончать! PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :

Book Description


Fortegnelse over de i 1821 ... indskrevne Studenter

Fortegnelse over de i 1821 ... indskrevne Studenter PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 4

Book Description


Measurement of Time-dependent CP Violation Asymmetries in B0-phi Ks0 Decay

Measurement of Time-dependent CP Violation Asymmetries in B0-phi Ks0 Decay PDF Author: Aleksey Chuvikov
Publisher:
ISBN:
Category :
Languages : en
Pages : 256

Book Description


Measurement of Time-Dependent CP-Violating Asymmetries in B0 -]K*0 Gamma (K*0-]K0[sub S] Pi0) Decays

Measurement of Time-Dependent CP-Violating Asymmetries in B0 -]K*0 Gamma (K*0-]K0[sub S] Pi0) Decays PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :

Book Description
We present a measurement of the time-dependent CP-violating asymmetries in B[sup 0] [yields] K*[sup 0][gamma](K*[sup 0] [yields] K[sub S][sup 0][pi][sup 0]) decays based on 124 million [Upsilon](4S) [yields] B[bar B] decays collected with the BABAR detector at the PEP-II asymmetric-energy B Factory at the Stanford Linear Accelerator Center. In a sample containing 105 [+-] 14 signal decays, we measure S[sub K*[sub [gamma]]] = 0.25 [+-] 0.63 [+-] 0.14 and C[sub K*[sub [gamma]]] = -0.57 [+-] 0.32 [+-] 0.09, where the first error is statistical and the second systematic.

Measurement of CP-Violating Asymmetries in B0 Decays to CP Eigenstates

Measurement of CP-Violating Asymmetries in B0 Decays to CP Eigenstates PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :

Book Description
We present measurements of time-dependent CP-violating asymmetries in neutral B decays to several CP eigenstates. The measurement uses a data sample of 23 million[Upsilon](4S)[yields] B[bar B] decays collected by the BABAR detector at the PEP-II asymmetric B Factory at SLAC. In this sample, we find events where one neutral B meson is fully reconstructed in a CP eigenstate containing charmonium and the flavor of the other neutral B meson is determined from its decay products. The amplitude of the CP-violating asymmetry, which in the Standard Model is proportional to sin2[beta], is derived from the decay time distributions in such events. The result is sin2[beta]= 0.34[+-] 0.20 (stat)[+-] 0.05 (syst).

The Measurement of Time-Dependent CP-Violating Asymmetries in Loop-Dominated B Decays with BABAR.

The Measurement of Time-Dependent CP-Violating Asymmetries in Loop-Dominated B Decays with BABAR. PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :

Book Description


Study of Time-Dependent CP Asymmetry in Neutral B Decays to J/[psi][pi]°

Study of Time-Dependent CP Asymmetry in Neutral B Decays to J/[psi][pi]° PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 7

Book Description
The authors present the first study of the time-dependent CP-violating asymmetry in B° 2!J/[psi][pi]° decays using ee− annihilation data collected with the BABAR detector at the [Upsilon](4S) resonance during the years 1999-2002 at the PEP-II asymmetric-energy B Factor at SLAC. Using approximately 88 million B{bar B} pairs, the results for the coefficients of the cosine and sine terms of the CP asymmetry are C{sub J/{psi}[pi]°} = 0.38 ± 0.41 (stat) ± 0.09 (syst) and S{sub J/{psi}[pi]°} = 0.05 ± 0.49 (stat) ± 0.16 (syst).

Study of CP-Violating Asymmetries in B0 --] Pi+ Pi-, K+ Pi- Decays

Study of CP-Violating Asymmetries in B0 --] Pi+ Pi-, K+ Pi- Decays PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 5

Book Description
We present a measurement of the time-dependent CP-violating asymmetries in neutral B decays to the??− CP eigenstate, and an updated measurement of the charge asymmetry in B° → K+?− decays. In a sample of 33 million?(4S) → B{bar B} decays collected with the BABAR detector at the SLAC PEP-II asymmetric B Factory, we find 65−11{sup +12}?+?− and 217 ± 18 K+?− candidates and measure the asymmetry parameters S{sub??} = 0.03{sub -0.56}{sup +0.53} ± 0.11, C{sub {pi}{pi}} = -0.25{sub -0.47}{sup +0.45} ± 0.14, and?{sub K{pi}} = -0.07 ± 0.08 ± 0.02, where the first error is statistical and the second is systematic.