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We present the first general measurements (invariant-mass, transverse-energy, and angular distributions) of the process, (p) over bar p-->gamma+2 jets + X, using data collected by the CDF at Fermilab. We compare the data with predictions from a tree-level QCD calculation and the PYTHIA shower Monte Carlo program. Our data sample is particularly sensitive to contributions from initial-and final-state radiation of photons and jets. Using the PYTHIA Monte Carlo program, we contrast the kinematical distributions for direct photon production with those for initial-and final-state photon radiation (bremsstrahlung). Based on the angular distributions, we find that our data favor a mixture of bremsstrahlung and direct photon production, as predicted, over either process alone

We report the first direct measurement of bb rapidity correlations in pp collisions at ͱsϭ1.8 TeV. We select events with a high transverse momentum muon accompanied by a jet, and a second jet associated with a decay vertex displaced from the pp interaction vertex. Two independent samples are obtained corresponding to events with a forward (2.0Ͻ͉͉Ͻ2.6) or central (͉͉Ͻ0.6) muon. We measure the ratio of forward to central bb production to be 0.361Ϯ0.033(stat) Ϫ0.031 ϩ0.015 (syst), in good agreement with the next-to-leading order QCD prediction 0.338 Ϫ0.097 ϩ0.014 .

Abstract. It is of importance to perform hydrological forecast using a finite hydrological time series. Most time series analysis approaches presume a data series to be ergodic without justifying this assumption. This paper presents a practical approach to analyze the mean ergodic property of hydrological processes by means of autocorrelation function evaluation and Augmented Dickey Fuller test, a radial basis function neural network, and the definition of mean ergodicity. The mean ergodicity of precipitation processes at the Lanzhou Rain Gauge Station in the Yellow River basin, the Ankang Rain Gauge Station in Han River, both in China, and at Newberry, MI, USA are analyzed using the proposed approach. The results indicate that the precipitations of March, July, and August in Lanzhou, and of May, June, and August in Ankang have mean ergodicity, whereas, the precipitation of any other calendar month in these two rain gauge stations do not have mean ergodicity. The precipitation of February, May, July, and December in Newberry show ergodic property, although the precipitation of each month shows a clear increasing or decreasing trend.