18633734
alphaPDE: A New multivariate technique for parameter estimation
Abstract We present α → PDE, a new multivariate analysis technique for parameter estimation. The method is based on a direct construction of joint probability densities of known variables and the parameters to be estimated. We show how posterior densities and best-value estimates are then obtained for the parameters of interest by a straightforward manipulation of these densities. The method is essentially non-parametric and allows for an intuitive graphical interpretation. We illustrate the method by outlining how it can be used to estimate the mass of the top quark, and we explain how the method is applied to an ensemble of events containing background.
119722876
Measurement of the dijet cross section in 400-GeV pp collisions
The invariant cross section for production of jet pairs in 400-GeV/c pp interactions has been measured as a function of p{tau} in the p{tau} range 4 to 9 GeV/c. The results are in good agreement with predictions of perturbative QCD models. 20 refs., 3 figs., 1 tab.
198138883
Experimental information on the pion gluon distribution function
An experiment performed at Fermilab used double-arm calorimeter triggers to study di-jet production by 400 GeV protons and 200 GeVπ− mesons incident on liquid hydrogen. The observed ratio of positive to negative leading particles in the jets was compared forpp andπp production using a tree level parton scattering model. The results are moderately sensitive to the form of the pion gluon distribution function and yieldx g(x)⋍(1−x)2.75±0.40±0.75.
120544624
Triggering on high-transverse-momentum jets
We compare the characteristics of events selected by ''global'' and ''two-high'' triggers in large-transverse-energy hadron-hadron collisions. Using a QCD-based Monte Carlo model of Fox and collaborators, we find that the former is effectively a high-multiplicity trigger, the latter a high-planarity trigger favoring unusually clean jet events. Predictions of the model for both triggers are in good qualitative agreement with recent data.
120365910
Modular TPCs for relativistic heavy-ion experiments☆
Abstract A description is given of a TPC system that operates in a relativistic heavy-ion beam and yields good track reconstruction efficiency in very-high-multiplicity events. The mechanical construction of the chamber is discussed. A set of custom hybrid circuits are used to build a very compact, cost-effective electronics system mounted directly on the chamber. Results from running in test beams and from preliminary experimental runs are given.
125525593
HADRON JETS IN 400-GeV p p COLLISIONS
120502863
Hadronic Production with a Drell-Yan Trigger
The ratio of cross sections for producing fast ${\ensuremath{\pi}}^{+}'\mathrm{s}$ and ${\ensuremath{\pi}}^{\ensuremath{-}}'\mathrm{s}$ in association with a massive dilepton should be a strongly varying function of the mass of the pair, reducing at small mass to its value in the absence of a pair. For $\frac{{{M}_{\ensuremath{\mu}\ensuremath{\mu}}}^{2}}{s}g0.1$, the $\frac{{\ensuremath{\pi}}^{+}}{{\ensuremath{\pi}}^{\ensuremath{-}}}$ ratio should fall by a factor of 1.7 in the reactions $p+\overline{p}\ensuremath{\rightarrow}\ensuremath{\pi}+({\ensuremath{\mu}}^{+}{\ensuremath{\mu}}^{\ensuremath{-}})+X$ and $p+{\ensuremath{\pi}}^{\ensuremath{-}}\ensuremath{\rightarrow}\ensuremath{\pi}+({\ensuremath{\mu}}^{+}{\ensuremath{\mu}}^{\ensuremath{-}})+X$, rise by a factor of 2.6 in $p+{\ensuremath{\pi}}^{+}\ensuremath{\rightarrow}\ensuremath{\pi}+({\ensuremath{\mu}}^{+}{\ensuremath{\mu}}^{\ensuremath{-}})+X$, and fall by about 25% in $p+p\ensuremath{\rightarrow}\ensuremath{\pi}+({\ensuremath{\mu}}^{+}{\ensuremath{\mu}}^{\ensuremath{-}})+X$.
116894731
Overlap Analysis of Two-Body Scattering Amplitudes
121815942
Evidence that hadronic interiors have a denser matter than charge distribution
Abstract An analysis of high-energy elastic and inelastic diffraction scattering provides strong evidence that the charge and matter densities of hadrons are different. When hadrons are treated as composite objects, then a correct Glauber analysis leads to an optical model with important corrections due to the hadronic wave function: One expects inelastic diffraction due to the fluctuations in the matter density of hadrons. Conversely, the experimental existence of dissociation processes gives phenomenological information about the hadronic wave function. We find the distribution of matter in nucleons to be denser than the observed charge distribution. This result has a natural interpretation from a constituent description of hadrons made from spin 1 2 quarks and colored vector gluons, which is a generalization of the Chou-Yang picture of diffraction scattering.
121339748
MOMENTUM TRANSFER DEPENDENCE IN DIFFRACTION DISSOCIATION.
Abstract The mechanism of kinematic coupling between momentum transfers in producing a low mass two particle system with double-peripheral dynamics is studied theoretically and model calculations. A method of data analysis which eliminates the effects of this kinematic reflection is presented. The data of the reaction pp → pnπ + at 19 GeV/ c have been analyzed using this method. It is seen that the high production slope of the low mass ηπ + system observed in this process is not a cosequences of double-peripheral dynamics plus kinematics but must be explicitly present in the invariant matrix element.
121154418
Dual properties of strangeness annihilation processes
Abstract The dual properties of strangeness annihilation processes are studied. Experimental evidence is presented for such processes building up a low-lying Regge singularity. Quark-diagram arguments suggest that this singularity is the exchange degenerate f'- ϕ trajectory. The possibility of studying the factorization properties of strangeness annihilation processes using hyperon beams is pointed out.