W. Chinowsky

Measurement of bottom quark production in 1.8 TeV

We present a measurement of the [ital b]-quark cross section in 1.8 TeV [ital p]-[ital [bar p]] collisions recorded with the Collider Detector at Fermilab using muonic [ital b]-quark decays. In the central rapidity region ([vert bar][ital y][sup [ital b]][vert bar][lt]1.0), the cross section is 295[plus minus]21[plus minus]75 nb (59[plus minus]14[plus minus]15 nb) for [ital p][sub [ital T]][sup [ital b]][gt]21 GeV/[ital c] (29 GeV/[ital c]). Comparisons are made to previous measurements and next-to-leading order QCD calculations.

p\bar{p}

Abstract Copious production of S ∗ decaying into π + π − is observed in ψ decay. (974 ± 4 - i 14 ± 5) MeV, consistent with the parameters extracted from couplede channel; fits to pheripheral π + π − and K + K − production experiments. The inclusive branching ratio for ψ → S ∗ + X is found to be (0.42 ± 0.08)%.

collisions using semileptonic decay muons

A module of the NESTOR underwater neutrino telescope, was deployed, in March 2003, at a depth of 3800m in order to test the overall detector performance and particularly that of the data acquisition systems. A prolonged period of running under stable operating conditions made it possible to measure the cosmic ray muon flux, I0 · cos a (θ). We also present our plans for the near future.

Observations of S∗ → π+π−in ψ decay

The prompt photon decay psi(3095)..--> gamma pi../sup +/..pi../sup -/..pi../sup +/..pi../sup -/ has been studied with the Mark II detector at SPEAR. This channel is found to contain a ..gamma..rho/sup 0/rho/sup 0/ component with rho/sup 0/rho/sup 0/ masses concentrated between 1.4 and 2.0 GeV/c/sup 2/. The branching fraction for the psi..--> gamma..rho/sup 0/rho/sup 0/ decay with masses less than 2.0 GeV/c/sup 2/ is measured to be (1.25 +- 0.35 +- 0.40) x 10/sup -3/.The prompt photon decay (3095)+-+- has been studied with the Mark II detector at SPEAR. This channel is found to contain a 00 component with 00 masses concentrated between 1.4 and 2.0 GeV/c2. The branching fraction for the 00 decay with masses less than 2.0 GeV/c2 is measured to be (1.25±0.35±0.40)×10-3.

Recent results from NESTOR

We present a measurement of jet shapes in [ital [bar p]p] collisions at [radical][ital s] =1.8 TeV at the Fermilab Tevatron using the Collider Detector at Fermilab (CDF). Qualitative agreement is seen with the predictions of recent next-to-leading [[ital O]([alpha][sub [ital s]][sup 3])] calculations and with leading logarithm QCD based Monte Carlo simulations. The dependence of the jet shape on transverse energy is studied.

Observation of the Decay 00

Abstract Inclusive momentum and energy spectra of neutral and charged D-mesons produced in e+e− annihilation at energies near 7 GeV are presented. The slope of the energy spectrum is similar to the charged pion spectrum at the same energy. The inclusive cross section σ(e+e−→ D or D + anything) at 7 GeV is 4.8±1.3 nb.

Measurement of jet shapes in p-barp collisions at sqrt s =1.8 TeV.

We present new results from the Antarctic Muon And Neutrino Detector Array (AMANDA), located at the South Pole in Antarctica. AMANDA-II, commissioned in 2000, is a multipurpose high energy neutrino telescope with a broad physics and astrophysics scope. We summarize the results from searches for a variety of sources of ultra-high energy neutrinos: TeV-PeV diffuse sources by measuring either muon tracks or cascades, neutrinos in excess of PeV by searching for muons traveling in the down-going direction, point sources, neutrinos originating from GRBs, and dark matter in the center of the Earth or Sun.

Inclusive production of D-mesons in e+e− annihilation at 7 GeV☆

An analysis of {ital W}- and {ital Z}-boson production using data from the Collider Detector at Fermilab at {radical}{ital s} =1.8 TeV yields {sigma}({ital W}{r arrow}{ital ev})/{sigma}({ital Z}{r arrow}{ital ee})=10.2{plus minus}0.8(stat){plus minus}0.4(syst). The width of the {ital W} boson, {Gamma}({ital W}), and a limit on the top-quark mass independent of decay mode are extracted from this measurement.

The AMANDA neutrino telescope

We present the dijet invariant-mass distribution in the region between 60 and 500 GeV, measured in 1.8-TeV {ital {bar p}p} collisions in the Collider Detector at Fermilab. Jets are restricted to the pseudorapidity interval {vert bar}{eta}{vert bar}{lt}0.7. Data are compared with QCD calculations; axigluons are excluded with 95% confidence in the region 120{lt}{ital M}{sub {ital A}}{lt}210 GeV for axigluon width {Gamma}{sub {ital A}}={ital N}{alpha}{sub s}{ital M}{sub {ital A}}/6, with {ital N}=5.

Measurement of the ratio sigma (W-->e nu )/ sigma (Z-->ee) in p-barp collisions at sqrt s =1.8 TeV.

The production rate of charged {ital D}{sup *} mesons in jets has been measured in 1.8-TeV {ital {bar p}p} collisions at the Fermilab Tevatron with the Collider Detector at Fermilab. In a sample of approximately 32 300 jets with a mean transverse energy of 47 GeV obtained from an exposure of 21.1 nb{sup {minus}1}, a signal corresponding to 25.0{plus minus}7.5(stat){plus minus}2.0(syst) {ital D}{sup *{plus minus}}{r arrow}K{sup {minus plus}}{pi}{sup {plus minus}}{pi}{sup {plus minus}} events is seen above background. This corresponds to a ratio {ital N}({ital D}{sup *+}+D{sup *{minus}})/N(jet) =0.10{plus minus}0.03{plus minus}0.03 for {ital D}{sup *} mesons with fractional momentum {ital z} greater than 0.1.