A set of inclusive cross sections at zero rapidity is presented for p-pbar interactions at center of mass energy sqrt(s)=1.8 TeV. Six particle cross sections are corrected for secondary contributions from decays of higher mass resonances in order to produce a set of primary cross sections. The primary cross sections per spin state are well described by d(sigma^p)/dy|_(y=0)= 0.721*(pi*lambdabar_(pi)^2)*exp(-m/T), where m is the particle rest mass, T=hbar*c/r_h, and r_h=0.97 fm. The deuterium production cross section is also described if r_h is replaced by r_A=r_h*A^(1/3). The same exponential in m and T describes primary charm fractions in e+e- collisions at least up to the J/Psi mass. There is no significant evidence for strangeness or charm suppression if only primary production of light hadrons is considered. There is evidence that the primary cross section for each particle may have the same value for pp and pbar-p collisions and that it may have nearly constant values between sqrt(s)=63 GeV and sqrt(s)=1800 GeV. Fits to the final state transverse momenta of the particles using a gas model favor a temperature T=132 MeV, a chemical potential mu=129 MeV, and a transverse flow of the gas with beta_f=0.27.

A set of inclusive cross sections at zero rapidity is presented for p-pbar interactions at center of mass energy sqrt(s)=1.8 TeV. Six particle cross sections are corrected for secondary contributions from decays of higher mass resonances in order to produce a set of primary cross sections. The primary cross sections per spin state are well described by d(sigma^p)/dy|_(y=0)= 0.721*(pi*lambdabar_(pi)^2)*exp(-m/T), where m is the particle rest mass, T=hbar*c/r_h, and r_h=0.97 fm. The deuterium production cross section is also described if r_h is replaced by r_A=r_h*A^(1/3). The same exponential in m and T describes primary charm fractions in e+e- collisions at least up to the J/Psi mass. There is no significant evidence for strangeness or charm suppression if only primary production of light hadrons is considered. There is evidence that the primary cross section for each particle may have the same value for pp and pbar-p collisions and that it may have nearly constant values between sqrt(s)=63 GeV and sqrt(s)=1800 GeV. Fits to the final state transverse momenta of the particles using a gas model favor a temperature T=132 MeV, a chemical potential mu=129 MeV, and a transverse flow of the gas with beta_f=0.27.

We have studied the charged multiplicity distributions arising from p-p and p-(p) over bar collisions over the range of center of mass energies from 30 to 1800 GeV. We find that a portion of each distribution does obey Koba-Nielsen-Olesen (KNO) scaling. Those parts of the distributions that do not scale are the result of collisions which are initiated by multiparton collisions. Results from experiment E735 show not only collisions initiated by double but also good evidence for triple parton-parton collisions. These multi-parton collisions seem to account for essentially all the increase in the nonsingle diffractive inelastic cross section in this energy domain. The threshold for multiparton collisions seems to be associated with the advent of sea quarks in the structure function of the proton. We have developed a means of extrapolating these results to higher energies. The results indicate that small Feynman x partons seem to become more dominant as the energy is increased. It seems very likely that the sea quarks are important at larger impact parameters than the valence quarks. This means that the gluons and sea quarks are increasingly important in describing the collisions as the energy grows. The threshold for multiparton collisions seems to be associated with the advent of the sea quarks in the reactions.

We have measured deconfined hadronic volumes, 4.4 < V < 13.0 fm(3), produced by a one-dimensional (ID) expansion. These volumes are directly proportional to the charged particle pseudorapidity densities 6.75 < dN(c)/d(eta) < 20.2. The hadronization temperature is T = 179.5 +/- 5(syst) MeV. Using Bjorken's 1 D model, the hadronization energy density is epsilon(F) = 1.10 +/- 0.26(stat) GeV/fm(3) corresponding to an excitation of 24.8 +/- 6.2(stat) quark-gluon degrees of freedom. (C) 2002 Elsevier Science B.V. All rights reserved.

We have ecamined the charged multiplicity distributions arising from p-p and [Formula: see text] at energies ranging from 30 GeV to 1800 GeV. We find that a portion of each distribution does indeed KNO scale. Those parts of the distributions that do not KNO scale are the result of multiparton collisions. Results from E735 at Fermilab seem to show evidence for both double and triple parton-parton collisions. These multiparton collisions seem to account for the increase in the non-single diffractive cross section in this energy domain.

We present the results of a search for the production of light elements in p¯p collisions at the Fermilab Tevatron collider. Momentum, time of flight, and dE/dx measurements are used to distinguish nuclei from elementary particles. A production ratio for deuterium to hydrogen is calculated and compared to the primordial value of the big bang model. Some evidence for tritium is found and none for helium isotopes.Received 10 February 2000DOI:https://doi.org/10.1103/PhysRevD.62.072004©2000 American Physical Society

We discuss the multiplicity distribution for the highest accessible energies of pp- and p̄p-interactions from the point of view of multiparton collisions. The inelastic cross sections for single, σ1, and multiple (double and, presumably, triple), σ2 parton collisions are calculated from the analysis of experimental data on the multiplicity distribution up to Tevatron energies. It is found that σ1 becomes energy independent while σ2 increases with s for s≥200 GeV. The observed growth of 〈p⊥〉 with multiplicity is attributed to the increasing role of multiparton collisions for the high-energy p̄p(pp)-inelastic interactions. σ2+3 reproduces quite well the cross-section for the mini-jet production.

We have examined charged multiplicities arising from p−p and p−p̄ collisions over the range of center of mass energies, s, from 30 GeV to 1800 GeV. Results from Tevatron experiment E735 support the presence of double parton interactions. These processes can be seen to account for a large fraction of the increase in the non single diffraction inelastic cross section from energies of about 200 GeV to 1800 GeV.

We argue that as the atomic number of the target nucleus A → ∞, the multiplicity of leading particles in hadron-nucleus collisions tends to a finite limit. The limiting multiplicities for various particle production are computed for both proton and pion projectiles. Signatures at finite A are discussed. Data from 100 GeV/c central hadron-nucleus collisions are analyzed and found to be in qualitative agreement with this picture.

In order to analyze data on joint charged-particle/photon distributions from an experimental search (T-864, MiniMax) for disoriented chiral condensate (DCC) at the Fermilab Tevatron collider, we have identified robust observables, ratios of normalized bivariate factorial moments, with many desirable properties. These include insensitivity to many efficiency corrections and the details of the modeling of the primary pion production, and sensitivity to the production of DCC, as opposed to the generic, binomial-distribution partition of pions into charged and neutral species. The relevant formalism is developed and tested in Monte-Carlo simulations of the MiniMax experimental conditions.

A small experiment, «MiniMax», has been set up in the C0 intersection region of the Fermilab Tevatron to seek evidence for disoriented chiral condensates and to study other forward physics phenomena. The experiment consists of a proportional wire chamber telescope accompanied by scintillation (trigger) counters, a lead converter, and followed by an electromagnetic calorimeter. The solid angle accepted is a cone centered at pseudorapidity (η) of 4.1 and of radius (in η-ϕ space) of about 0.6. Over 2.5 million events thus far have demonstrated the successful operation of the apparatus, however to date the analysis has not progressed sufficiently to permit any conclusions concerning disoriented chiral condensates.

We report on the progress of a search for disoriented chiral condensates (DCCs) in the far forward region at sqrt(s)=1.8 TeV. MiniMax is a small collider experiment situated at the C0 interaction region of the Tevatron and has been designed to measure the ratio of charged to neutral pions produced at eta near 4.1. The distribution of this ratio is expected to be very different for the generic binomial and DCC particle production models. We present a method used for the search using the factorial moments of particle generating functions, which can be extracted directly from the data. A preliminary comparison of robust ratios of measured values and those expected from the different models is also presented.

The correlations between charged particle multiplicities produced in forward and backward pseudorapidity regions in p $($) over bar$$ p interactions have been measured with a 240 element scintillator hodoscope. The correlation coefficient and the variance of the difference of multiplicities in the two pseudorapidity regions were determined for root s = 0.3-1.8 TeV. These results have been interpreted in terms of a cluster model of particle production.

Fermilab experiment E735 located at the CO intersection region of the <img src="/fulltext-image.asp?format=htmlnonpaginated&src=X754331UN2103624_html\10052_2005_Article_BF01624584_TeX2GIFIE3.gif" border="0" alt=" $$\sqrt s = 1.8$$ " /> TeV <img src="/fulltext-image.asp?format=htmlnonpaginated&src=X754331UN2103624_html\10052_2005_Article_BF01624584_TeX2GIFIE4.gif" border="0" alt=" $$p\bar p$$ " /> collider analysed over 900 Φ→K+K− events. Measured were the transverse momentum spectrum, the correlation between the average transverse momentum pt> and the charged particle multiphcityNc, as well as the probability of Φ production per charged track,NΦ/Nc, versusNc. We have also made an estinate of the total inclusive cross section for Φ mesons, <img src="/fulltext-image.asp?format=htmlnonpaginated&src=X754331UN2103624_html\10052_2005_Article_BF01624584_TeX2GIFIE5.gif" border="0" alt=" $$\sigma (p\bar p \to \phi X) = 7.3 \pm 2.2 mb$$ " />.

Fermilab experiment E735 located at the CO intersection region of the\(\sqrt s = 1.8\) TeV\(p\bar p\) collider analysed over 900 Φ→K+K− events. Measured were the transverse momentum spectrum, the correlation between the average transverse momentum and the charged particle multiphcityN c , as well as the probability of Φ production per charged track,N Φ /N c , versusN c . We have also made an estinate of the total inclusive cross section for Φ mesons,\(\sigma (p\bar p \to \phi X) = 7.3 \pm 2.2 mb\).

Transverse momentum spectra of charged particles produced within the pseudo-rapidity range of η= − 0.36 to + 1.0 have been measured in pp collisions at √s=0.3, 0.54, 1.0, and 1.8 TeV. The spectra are presented as a function of event charged multiplicity within the range −3.25<η<3.25. We found that the slope in the low pt region is independent of center-of-mass energy and multiplicity while the slope at the high pt region shows a strong energy and multiplicity dependence.