R. Gardner

First evidence of

Abstract We report evidence of a narrow resonance at a mass of 2705.9 ± 3.3 ± 2.0 MeV/c2 in the final state Ω−π+ and the charge conjugate. The mass and width support the interpretation of a weakly decaying doubly strange charmed baryon, the Ω c 0 . Limits on the relative branching ratios for Ω c 0 →Ω − K − π + π + and Ω c 0 →Ω − π − π + π + are also presented.

Analysis of the decay mode D+ ---> anti-K*0 mu+ neutrino

Abstract Fermilab high-energy photoproduction experiment E687 provides a high statistics sample of the decay mode D + → K ∗0 μ + ν (charge conjugates are implied). Our analysis yields a branching ratio of Γ (D + → K ∗0 μ + ν) Γ (D + → K − π + π + ) = 0.56±0.04±0.06 . The ratios of the form factors governing the decay are measured to be R ν = 1.74 ±0.27±0.28 and R 2 = 0.78±0.18±0.10, implying a polarization of Γ l Γ t = 1.20±0.13 ±0.13 for the electron decay. Finally, we report new limits on the decay modes D + → K − π + μ + ν (nonresonent) and D + → K ∗0 π 0 μ + ν .

Measurement of the lifetime of the Xi c0.

A measurement of the lifetime of the charmed strange baryon [Xi][sub [ital c]][sup 0] is presented. The data were accumulated by the Fermilab high energy photoproduction experiment E687. The measurement has been made using 42[plus minus]10 [Xi][sub [ital c]][sup 0][r arrow][Xi][sup [minus]][pi][sup +] decays. The lifetime of the [Xi][sub [ital c]][sup 0] is measured to be 0.101[sub [minus]0.017][sup +0.025][plus minus]0.005 ps and its mass is measured to be 2462.1[plus minus]3.1[plus minus]1.4 MeV/[ital c][sup 2].

Search for CP violation in the decays D+ ---> K(S) pi+ and D+ ---> K(S) K+

A high statistics sample of photo-produced charm from the FOCUS(E831) experiment at Fermilab has been used to search for direct CP violation in the decays D+->K_S pi+ and D+ ->K_S K+. We have measured the following asymmetry parameters relative to D+->K-pi+pi+: A_CP(K_S pi+) = (-1.6 +/- 1.5 +/- 0.9)%, A_CP(K_S K+) = (+6.9 +/- 6.0 +/- 1.5)% and A_CP(K_S K+) = (+7.1 +/- 6.1 +/- 1.2)% relative to D+->K_S pi+. The first errors quoted are statistical and the second are systematic. We also measure the relative branching ratios: \Gamma(D+->\bar{K0}pi+)/\Gamma(D+->K-pi+pi+) = (30.60 +/- 0.46 +/- 0.32)%, \Gamma(D+->\bar{K0}K+)/\Gamma(D+->K-pi+pi+) = (6.04 +/- 0.35 +/- 0.30)% and \Gamma(D+->\bar{K0}K+)/\Gamma(D+->\bar{K0}pi+) = (19.96 +/- 1.19 +/- 0.96)%.

A Precise measurement of the D(S)+- meson lifetime

A precise measurement of the D s ± meson lifetime is reported. The data were accumulated by the high energy photoproduction experiment E687 at Fermilab in the 1990-1991 fixed target run. The measurement has been done using 900 fully reconstructed D s ± →Oπ ± decays. The lifetime of the D s ± meson is measured to be 0.475±0.020±0.007 psA precise measurement of the [ital D][sub [ital s]][sup [plus minus]] meson lifetime is reported. The data were accumulated by the high energy photoproduction experiment E687 at Fermilab in the 1990--1991 fixed target run. The measurement has been done using 900 fully reconstructed [ital D][sub [ital s]][sup [plus minus]][r arrow][phi][pi][sup [plus minus]] decays. The lifetime of the [ital D][sub [ital s]][sup [plus minus]] meson is measured to be 0.475[plus minus]0.020[plus minus]0.007 ps.

Branching ratios of the decays D0 ---> anti-K0 K0 and D0 ---> K0(s) K0(s) K0(s)

Abstract The branching ratios of D 0 → K 0 K 0 and D0 → Ks0Ks0Ks0 relative to D 0 → K 0 π + π − are reported. The data were accumulated in the 1990–1991 fixed target running period of the Fermilab high energy photoproduction experiment E687. Γ (D 0 → K 0 K 0 )/Γ (D 0 → K 0 π + π − is measured to be 0.039±0.013±0.013 and Γ (D 0 →K s 0 K s 0 K s 0 )/Γ (D 0 → K 0 π + π − ) is measured to be 0.035±0.012±0.006. We also measure Γ (D 0 → K 0 π + π − /Γ (D 0 → K − π + ) to be 1.61±0.10±0.15.

Overview of the BTeV program

BTeV is a dedicated experiment to carry out precision studies of CP violation, mixing, and rare decays of beauty and charm hadrons in the forward direction at the Fermilab Tevatron Collider. The detector is designed to have excellent particle identification for charged and neutral hadrons and photons, excellent mass and decay time resolutions, and a trigger system capable of selecting both hadronic and leptonic final states using detached vertices at the lowest level of the trigger. Some specific goals of the experiment include precision measurements of the CKM angles γ using Bs→Ds±K∓ (and other methods), α using B0→ρπ, and the important but small CP asymmetry in the final state Bs→ψη′. We discuss the performance of BTeV for the first of these methods after giving an overview of the detector.

Radiative φ decays at Jefferson Lab

We discuss the status and future prospects of a program to study radiative φ decays in at Jefferson Lab.

Search forCPViolation in the decaysD+→KSπ+andD+→KSK+

A high statistics sample of photo-produced charm from the FOCUS(E831) experiment at Fermilab has been used to search for direct CP violation in the decays D+->K_S pi+ and D+ ->K_S K+. We have measured the following asymmetry parameters relative to D+->K-pi+pi+: A_CP(K_S pi+) = (-1.6 +/- 1.5 +/- 0.9)%, A_CP(K_S K+) = (+6.9 +/- 6.0 +/- 1.5)% and A_CP(K_S K+) = (+7.1 +/- 6.1 +/- 1.2)% relative to D+->K_S pi+. The first errors quoted are statistical and the second are systematic. We also measure the relative branching ratios: \Gamma(D+->\bar{K0}pi+)/\Gamma(D+->K-pi+pi+) = (30.60 +/- 0.46 +/- 0.32)%, \Gamma(D+->\bar{K0}K+)/\Gamma(D+->K-pi+pi+) = (6.04 +/- 0.35 +/- 0.30)% and \Gamma(D+->\bar{K0}K+)/\Gamma(D+->\bar{K0}pi+) = (19.96 +/- 1.19 +/- 0.96)%.

Search for CP Violation in the decays [Formula presented] and [Formula presented]

A high statistics sample of photo-produced charm from the FOCUS(E831) experiment at Fermilab has been used to search for direct CP violation in the decays D+->K_S pi+ and D+ ->K_S K+. We have measured the following asymmetry parameters relative to D+->K-pi+pi+: A_CP(K_S pi+) = (-1.6 +/- 1.5 +/- 0.9)%, A_CP(K_S K+) = (+6.9 +/- 6.0 +/- 1.5)% and A_CP(K_S K+) = (+7.1 +/- 6.1 +/- 1.2)% relative to D+->K_S pi+. The first errors quoted are statistical and the second are systematic. We also measure the relative branching ratios: \Gamma(D+->\bar{K0}pi+)/\Gamma(D+->K-pi+pi+) = (30.60 +/- 0.46 +/- 0.32)%, \Gamma(D+->\bar{K0}K+)/\Gamma(D+->K-pi+pi+) = (6.04 +/- 0.35 +/- 0.30)% and \Gamma(D+->\bar{K0}K+)/\Gamma(D+->\bar{K0}pi+) = (19.96 +/- 1.19 +/- 0.96)%.