114186762
Conceptual design for a silicon tracker at the SSC
16089528
Observation of radiative leptonic decay of the tau lepton
Using 4.68 fb(-1) of e(+)e(-) annihilation data collected with the CLEO II detector at the Cornell Electron Storage Ring, we have studied tau radiative decays tau(-)-->nu(tau)&mgr;(-)nu;(&mgr;)gamma and tau(-)-->nu(tau)e(-)nu;(e)gamma. For a 10 MeV minimum photon energy in the tau rest frame, the branching fraction for radiative tau decay to a muon or electron is measured to be (3.61+/-0.16+/-0. 35)x10(-3) or (1.75+/-0.06+/-0.17)x10(-2), respectively. The branching fractions are in agreement with standard model theoretical predictions.
117035924
Measurement of B (tau- ---> tau-neutrino K- K0) and b (tau- ---> tau-neutrino K- K0 pi0)
12584275
Study of charmless hadronic B meson decays to pseudoscalar-vector final states.
We report results of searches for charmless hadronic B meson decays to pseudoscalar( pi(+/-), K+/-, pi(0), or K(0)(S))-vector( rho, K(*), or omega) final states. By using 9.7x10(6) BB pairs collected with the CLEO detector, we report the first observation of B(-)--->pi(-)rho(0), B(0)-->pi(+/-)rho(-/+), and B(-)-->pi(-)omega, which are expected to be dominated by hadronic b-->u transitions. The measured branching fractions are (10.4(+3.3)(-3.4)+/-2.1)x10(-6), (27.6(+8.4)(-7.4)+/-4.2)x10(-6), and (11.3(+3.3)(-2.9)+/-1. 4)x10(-6), respectively. Branching fraction upper limits are set for all of the other decay modes investigated.
34604877
Measurement of Cabibbo-suppressed decays of the tau lepton.
Branching ratios for the dominant Cabibbo-suppressed decays of the [tau] lepton have been measured by CLEO II in [ital e][sup +][ital e][sup [minus]] annihilation at the Cornell Electron Storage Ring ([radical][ital s] [similar to]10.6 GeV) using kaons with momenta below 0.7 GeV/[ital c]. The inclusive branching ratio into one charged kaon is (1.60[plus minus]0.12[plus minus]0.19)%. For the exclusive decays, [ital B]([tau][sup [minus]][r arrow][ital K][sup [minus]][nu][sub [tau]])=(0.66[plus minus]0.07[plus minus]0.09)%, [ital B]([tau][sup [minus]][r arrow][ital K][sup [minus]][pi][sup 0][nu][sub [tau]])=(0.51 [plus minus]0.10[plus minus]0.07)%, and, based on three events, [ital B]([tau][sup [minus]][r arrow][ital K][sup [minus]]2[pi][sup 0][nu][sub [tau]])[lt]0.3% at the 90% confidence level. These represent significant improvements over previous results. [ital B]([tau][sup [minus]][r arrow][ital K][sup [minus]][pi][sup 0][nu][sub [tau]]) is measured for the first time with exclusive [pi][sup 0] reconstruction.
181671081
Search for B ---> K lepton+ lepton- and B ---> K* lepton+ lepton- decays
60584564
The PEP-II Project-Wide Database
The PEP-II Project Database is a tool for monitoring the technical and documentation aspects of this accelerator construction. It holds the PEP-II design specifications, fabrication and installation data in one integrated system. Key pieces of the database include the machine parameter list, magnet and vacuum fabrication data, CAD drawings, publications and documentation, survey and alignment data, and property control. The database can be extended to contain information required for the operations phase of the accelerator and detector. Features such as viewing CAD drawing graphics from the database will be implemented in the future. This central Oracle database on a UNIX server is built using Oracle*Case tools. Users at the three collaborating laboratories (SLAC, LBL, LLNL) can access the data remotely, using various desktop computer platforms and graphical interfaces.
102476015
Measurement of CP asymmetries in $B^0 \to K_s 0 \pi^0 \pi^0$ decays
We present a preliminary measurement of the time-dependent CP asymmetry for the neutral B-meson decay into the CP = +1 final state KS pi0 pi0, with KS-> pi+ pi- and pi0-> gamma gamma. We use a sample of approximately 227 million B-meson pairs recorded at the Y(4S) resonance by the BaBar detector at the PEP-II B-Factory at SLAC. From a maximum likelihood fit we extract the mixing-induced CP-violation parameter S = 0.84 +/- 0.71(stat} +/- 0.08{syst) and the direct CP-violation parameter C = 0.27 +/- 0.52(stat) +/- 0.13(syst}, where the first uncertainty is statistical and the second systematic.
118876977
Discovery of very high energy gamma-ray radiation from the BL Lac 1ES 0806+524
The high-frequency-peaked BL Lacertae object 1ES 0806+524, at redshift z = 0.138, was observed in the very high energy (VHE) gamma-ray regime by VERITAS between 2006 November and 2008 April. These data encompass the two- and three-telescope commissioning phases, as well as observations with the full four-telescope array. 1ES 0806+524 is detected with a statistical significance of 6.3 standard deviations from 245 excess events. Little or no measurable variability on monthly timescales is found. The photon spectrum for the period 2007 November to 2008 April can be characterized by a power law with photon index 3.6 ± 1.0stat ± 0.3sys between ~ 300 GeV and ~ 700 GeV. The integral flux above 300 GeV is (2.2 ± 0.5stat ± 0.4sys) × 10–12 cm–2 s–1 which corresponds to 1.8% of the Crab Nebula flux. Non-contemporaneous multiwavelength observations are combined with the VHE data to produce a broadband spectral energy distribution that can be reasonably described using a synchrotron--self-Compton model.
195861912
Electronics for the BaBar central drift chamber
The central drift chamber for the BaBar detector at the SLAC B-factory is based on a hexagonal cell design with 7104 cells arranged in 40 layers and drift gas helium:isobutane (80%:20%). Performance optimization and integration requirements led to an electronics design that mounts the amplifier-discriminator and digitizing circuitry directly on the endplate. High channel density is achieved using a 4-channel custom amplifier-discriminator IC and an 8-channel custom CMOS TDC/FADC IC on a single circuit board. Data read from the front ends are multiplexed on 4 fiber optic links, and prompt trigger data are sent out continuously on 24 links. Analysis of cosmic ray data demonstrates that the electronics design meets the performance goals for the BaBar drift chamber. The final electronics were installed on the drift chamber in July, 1998. Installation of BaBar on beamline is scheduled for March, 1999.
126117137
Measurement of $\sin$ 2 beta in $B^0 \to \phi K^0_{s}$