[en] We present a measurement of the inclusive jet cross section in bar pp collisions at √s =1.8 TeV at the Fermilab Tevatron using the Collider Detector at Fermilab. Good agreement is seen with the predictions of recent next-to-leading-order [O(α_s³)] QCD predictions. The dependence of the cross section on clustering cone size is reported for the first time. An improved limit on Λ_c, a term characterizing possible quark substructure, is set at 1.4 TeV (95% C.L.)

[en] The CLEO II detector at the e⁺e^- storage ring CESR has been used to search for two-photon production of the f_J(2220) decaying into π⁺π^- . No evidence for a signal is found in 4.77 fb^-1 of data and a 95% C.L. upper limit on [Γ_γγB_π⁺π^-]_fJ(2220) of 2.5eV is set. If this result is combined with the BES Collaboration close-quote s measurement of f_J(2220)→π⁺π^- in radiative J/ψ decay and the recent CLEO result for [Γ_γγB_K⁰SK⁰S]_fJ(2220) , a 95% C.L. lower limit on the stickiness of 102 is obtained. This result for the stickiness provides further support for a substantial neutral parton content in the f_J(2220) . copyright 1998 The American Physical Society

[en] We report the first observation of two narrow charmed strange baryons decaying to Ξ⁺_cγ and Ξ⁰_cγ , respectively, using data from the CLEO II detector at the Cornell Electron Storage Ring. We interpret the observed signals as the Ξ^+'_c( c{su}) and Ξ^0'_ct( c{sd}) , the symmetric partners of the well-established antisymmetric Ξ⁺_ct(c[ su]) and Ξ⁰_c(c[ sd]) . The mass differences M(Ξ^+'_c)-M( Ξ⁺_c) and M(Ξ^0'_c)-M( Ξ⁰_c) have been measured to be 107.8±1.7±2.5 and 107.0±1.4±2.5 MeV /c² , respectively. copyright 1999 The American Physical Society

[en] We report new measurements of the differential and total branching ratios for inclusive B decay to D⁰, D⁺, and D^*+ and the first measurement of the same quantities for inclusive B decay to D^*0. Here B is the mixture of B_d and B_u from Υ(4S) decay. Furthermore, since more than one charm particle (or antiparticle) of the same kind can be produced in B decay, here open-quotes inclusive B branching ratioclose quotes is used to mean the average number of charm particles and their antiparticles of a certain species produced in B decay. We obtain the following results (the first error is statistical, the second systematic of this analysis, the third propagated from other measurements): B(B→D⁰X)=(0.636±0.014±0.019±0.0 8), B(B→D⁺X)=(0.235±0.009±0.009±0.024), B(B→D^*0X) =(0.247±0.012±0.018±0.018), B(B→D^*+X)=(0.239±0.011±0.014±0. 09). The following ratio of branching ratios is not affected by most of the systematic errors: B(B→D^*0X)/ B(B→D^*+X)=(1.03±0.07±0.09±0.08). We also report the first measurement of the momentum-dependent D^*0 polarization and a new measurement of the D^*+ polarization in inclusive B decay. Using these measurements and other CLEO results and making some additional assumptions, we calculate the average number of c and bar c quarks produced in B decay to be left-angle n_c right-angle=1.10±0.05. copyright 1997 The American Physical Society

[en] Using data recorded by the CLEO-II detector at CESR, we report new measurements of the branching fractions for the decays of the charmed baryon Λ_c⁺ into pK^-π⁺π⁰, p bar K⁰, p bar K⁰π⁺π^-, and p bar K⁰π⁰, all measured relative to pK^-π⁺. The relative branching fractions are 0.67±0.04±0.11,0.46±0.02±0.04,0.52 ±0.04±0.05, and 0.66±0.05±0.07, respectively. copyright 1998 The American Physical Society

[en] Using data collected in the region of the Υ(4S) resonance with the CLEO-II detector, we report on the first observation of exclusive decays of the B meson to final states with a charmed baryon. We have measured the branching fractions B(B^-→Λ⁺_cpπ^-)=( 0.62^+0.23_-0.20±0.11±0.10) x10^-3 and B(B⁰→Λ⁺_cpπ⁺π^-)=(1.33^+0.46_-0.42±0.31±0.21)x1

[en] We report a measurement of the proton-antiproton total cross section σ_T at c.m.s. energies √s =546 and 1800 GeV. Using the luminosity-independent method, we find σ_T=61.26±0.93 mb at √s =546 GeV and 80.03±2.24 mb at √s =1800 GeV. In this energy range, the ratio σ_el/σ_T increases from 0.210±0.002 to 0.246±0.004

[en] The production and event topology of three-jet events produced in p bar p collisions at √s =1.8 TeV have been studied with the Collider Detector at Fermilab at the Tevatron Collider. The distributions of the three-jet angular variables (ψ^* and cosθ^*) and of the variables describing the energy sharing between jets (x₃ and x₄) are found to agree well with tree-level QCD calculations. These distributions are predicted to have different shapes for different initial-state subprocesses (quark-antiquark, quark-gluon, and gluon-gluon). The data are consistent with the small expected contribution from quark-antiquark initial states, in agreement with theoretical expectations

[en] During the 1988/1989 run at the Fermilab Tevatron, the CDF detector collected ≅ 4.1 pb^-1 of p bar p data at √s = 1.8 TeV. The main goals of this run being physics at high p_t, the CDF trigger was tuned for maximizing signals from Z⁰s, Ws, t-quarks, and etc. As such, compared to the high pt physics, the b-physics program was of secondary importance other than that which would be used for background calculations. Also, CDF had no vertex chamber capability for seeing displaced vertices. However, significant b-quark physics results are evident in two data samples: (1) inclusive electrons; (2) inclusive J/ψ where J/ψ → μ⁺μ^-. In this paper, the author will try to specify the goals for b-physics using the inclusive electrons and J/ψ signals for the 1988/89 data set. He will then provide a brief look at the data, and will finish with some highly speculative guesses as to whether or not experiments at the Tevatron which look for CP violation in the b sector are possible

[en] We have searched for the effective flavor changing neutral-current decays b→sl⁺l^- using an inclusive method. We set upper limits on the branching ratios B(b→se⁺e^-)< 5.7x10^-5 , B(b→sμ⁺μ^- )<5.8x10^-5 , and B(b→se^±μ^minus-plus )<2.2x10^-5 [at 90% confidence level (C.L.)]. Combing the dielectron and dimuon decay modes we find B(b→sl⁺l^-)< 4.2x10^-5 (at 90% C.L.). copyright 1998 The American Physical Society