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Comparison of PWA results of K{sup +}K{sup o}{sub s} {pi}{sup {minus}} final states produced in 8 GeV/c K{sup {minus}}p, {pi}{sup {minus}} p and {bar p}p interactions

Description: We have performed partial-wave analyses of the K{sup +}K{sup o}s {pi}{sup {minus}} system produced in the reactions K{sup {minus}}p {yields} K{sup +}K{sup o}s{pi}{sup {minus}}, {Lambda}/{Sigma}, {pi}{sup {minus}}p {yields} K{sup +}K{sup o}s {pi}{sup {minus}}n and {bar p}p {yields} K{sup +}K{sup o}s{pi}{sup {minus}} X at 8 GeV/c in substantially the same apparatus. We present and compare the results of the analysis of the three reactions in the mass range 1.24 GeV/c{sup 2} < M(KK{pi}) <1.56 GeV/c{sup 2}. In all three reactions the J{sup PG} = O{minus_plus}, 1{plus_minus} and 1{sup ++} waves are the most important. A strong f{sub 1}(1285) signal is evident in the {pi} and {bar p} beam data sets but not in the K data. There is evidence of {eta}(l280) production, especially in the n and 0 beam data. We find evidence of two O{sup {minus_plus}} states in the 1400 MeV/c{sup 2} mass region, but no compelling case for a 1{sup ++} resonance in this region. Finally, the 1{sup {plus_minus}} wave in the K beam data is consistent with an h` state below the K*K threshold.
Date: December 31, 1991
Creator: Bar-Yam, Z.; Dowd, J.; Kern, W.; King, E.; Rulon, P.; Blessing, S. K. et al.
Partner: UNT Libraries Government Documents Department

Experimental investigations of strong interaction in the non-perturbative QCD region. Annual progress report, January 16, 1993--January 15, 1994

Description: A critical investigation of non-perturbative QCD require investigating glueballs, search for a Quark Gluon Plasma (OGP), and search for strangelets. In the glueball area the data obtained (E- 881) at 8 GeV/c were analyzed for {pi}{sup {minus}} + p {yields} {phi}{phi}n (OZI forbidden), {phi}K{sup +}K{sup {minus}}n (OZI allowed), K{sup {minus}}p {yields} {phi}{phi}({Lambda}{Sigma}) (OZI allowed), and {bar p}p {yields} {phi}{phi} {yields} {phi}{phi}{pi}{sup 0} (OZI forbidden), {phi}K{sup +}K{sup {minus}}{pi}{sup 0} (OZI allowed). By comparing the OZI forbidden (glueball filter reactions) with the OZI allowed and previous 22 GeV/c {pi}{sup {minus}}p {yields} {phi}{phi}n or {phi}K{sup +}K{sup {minus}}n data a further critical test of the so far unsuccessfully challenged hypothesis that our g{sup T}(2010), g{sub T}{prime}(2300) and g{sub T}{double_prime}(2340) all with I{sup G}J{sup PC} = 0{sup +}2{sup ++} are produced by 1-3 2{sup ++} glueballs will be made. In the QGP search with a large-solid-angle TPC a good {Xi} signal was observed. The ratio of {Xi} to single strange quark particles such as {lambda} is a better indication of strangeness enhancement in QGP formation. The data indicate enhancement by a factor {approx} 2 over cascade model (corrected to observed strangeness) predictions, but it is definitely far from conclusive at this stage since the result is model dependent. Double {lambda} topologies of the type needed to discover light strangelets in the nanosecond lifetime region were found. In addition, research has been accomplished in three main areas: bosonic technicolor and strings, buckministerfullerene C{sub 60} and neutrino oscillations in a dense neutrino gas.
Date: September 1, 1993
Creator: Lindenbaum, S. J. & Samuel, S.
Partner: UNT Libraries Government Documents Department

Evidence for explicit glueballs from the reaction. pi. /sup -/p. -->. phi phi n/sup +/

Description: Given QCD as an Ansatz and OZI (with appropriate restrictions) as a second Ansatz, I conclude we have discovered either two glueballs or two states very rich in resonating glue formed from one primary glueball mixing with a nearby quark state of the same quantum numbers, thus forming two states.
Date: January 1, 1982
Creator: Lindenbaum, S.J.
Partner: UNT Libraries Government Documents Department

Search for narrow states produced in the reaction. pi. /sup -/p. --&gt;. n +. gamma. &#x27;s at 13 GeV/c

Description: A double arm lead-glass lead-scintillator calorimeter system was used to search for narrow states, such as the eta/sub c/, produced in the exclusive reactions ..pi../sup -/p ..--&gt;.. ..gamma gamma..n, ..pi../sup -/p ..--&gt;.. ..pi../sup 0/..gamma..n, and ..pi../sup -/p ..--&gt;.. ..pi../sup 0/..pi../sup 0/n at 13 GeV/c. A 90% c.l. upper limit sigma.BR &lt; 260 pb was found for ..gamma gamma.. states with masses from 2.6 to 3.1 GeV/c/sup 2/. Corresponding limits on narrow ..pi../sup 0/..gamma.. and ..pi../sup 0/..pi../sup 0/ states are also given.
Date: July 7, 1980
Creator: Chiang, I-H; Johnson, R A & Kwan, B
Partner: UNT Libraries Government Documents Department

Search for narrow anti pp states in the reaction. pi. /sup -/p. --&gt;. p. pi. /sup -/ anti pp at 16 GeV/c

Description: A sensitive (greater than or equal to 5 events/nb) search for narrow anti pp states was carried out at the BNL Multiparticle Spectrometer. No evidence of narrow anti pp states was found at 2020 and 2200 MeV in the reaction ..pi../sup -/p ..--&gt;.. p..pi../sup -/ anti pp at 16 GeV/c. 2 sigma upper limits of less than or equal to 3 nb are quoted for these states in the data. Based on the cross sections of the CERN ..cap omega.. experiment at 12 GeV/c and assuming baryon-exchange processes for the production, greater than or equal to 5 sigma signals should have been seen at 2020 and 2200 MeV.
Date: January 1, 1980
Creator: Chung, S U; Etkin, A & Fernow, R
Partner: UNT Libraries Government Documents Department

Hadronic production of J/sup PC/ = 2/sup + +/ glueballs

Description: An OZI suppressed channel with variable mass, namely the reaction ..pi../sup -/p ..-->.. phi phi n, has been used as a filter which allows resonating gluons or glueballs to pass, while strongly rejecting conventional quark-built hadronic states. The breakdown of the OZI suppression signals a glueball. Glueball mass and particle width estimates are discussed. Reasons why g/sub T/'s have not been seen in other channels, particularly the decay of J/psi, are considered. 34 refs., 9 figs. (LEW)
Date: March 17, 1986
Creator: Lindenbaum, S.J.
Partner: UNT Libraries Government Documents Department

QCD, OZI, and evidence for glueballs

Description: The characteristics expected from low Q-QCD for the behavior of glueballs and the OZI rule is discussed. The reaction ..pi../sup -/p ..-->.. phi phi n represents on OZI forbidden (hairpin) diagram. It has been observed at the Brookhaven National Laboratory multiparticle spectrometer by the Brookhaven National Laboratory/City College of New York group. The author has shown that the expected OZI suppression is essentially entirely absent and in fact the Isobar Model which does not contain OZI suppression quantitatively explains the observed results. A general evaluation of the special characteristics of the data compared to other related reactions plus the foregoing facts leads the author to conclude that the intervention of glueball resonances is the likely explanation in the context of QCD. Other explanations are shown to be improbable. In particular the hypothesis that decay of a radial excitation of the eta' is responsible for lack of OZI suppression is ruled out. Planned experiments with the purpose of explicity discovering glueballs will be discussed. The OZI rule peculiarities such as violation of crossing symmetry and unitarity are attributed to color confinement.
Date: January 1, 1981
Creator: Lindenbaum, S.J.
Partner: UNT Libraries Government Documents Department

Observation and phenomenology of glueballs

Description: The experimental evidence and the relevant phenomenology of glueballs are reviewed. The opinion is expressed that the glueball resonance explanation is the only viable one for the data on g/sub T/, g/sub T/sup 1//, and g/sub T/sup 11//. It is shown that alternative explanations are either incorrect, or do not fit the data, or both, leading to the conclusion that these states are probably produced by glueballs. The OZI rule is explained. Glueball masses and width are considered. Some conclusions are drawn regarding an OZI suppressed reaction ..pi../sup -/p ..-->.. phi phi n. Glueball candidates from the J/psi radiative decay are discussed. 44 refs., 16 figs. (LEW)
Date: January 1, 1985
Creator: Lindenbaum, S.J.
Partner: UNT Libraries Government Documents Department

Measurement of high-p/sub T/ correlations in 340-GeV/c pp and 280-GeV/c. pi. /sup -/p reactions

Description: We have measured correlations between single high-p/sub T/ (1.5 < p/sub T/ < 3.5 GeV/c) trigger particles on one side of the beam line and groups of particles entering a calorimeter on the opposite side of the beam line. The mean transverse momentum measured in the calorimeter is found to increase with the trigger-particle transverse momentum. The coplanarity of the events increases with trigger-particle transferse momentum. We have compared our data to the predictions of a phenomenological four-jet model. To fit our data we find that we must give large (0.9 GeV/c) mean transverse momenta to the constituents of the initial hadrons.
Date: March 1, 1983
Creator: Oliver, W.P.; Limon, P. & Mantsch, P.
Partner: UNT Libraries Government Documents Department

Fluctuations in large-angle. pi. /sup + -/p elastic scattering. [2 to 9. 7 GeV/c, differential cross sections]

Description: An experiment was performed to search systematically for fluctuations in ..pi../sup +/p elastic scattering from 2 to 6.3 GeV/c and ..pi../sup -/p from 2 to 9.7 GeV/c. Differential cross sections are plotted. Three references. (JFP)
Date: January 1, 1978
Creator: Jenkins, K.A.; Price, L.E.; Klem, R.; Miller, R.J.; Schreiner, P.; Courant, H. et al.
Partner: UNT Libraries Government Documents Department

Search for a J/sup PC/ exotic hybid meson

Description: This paper describes an experiment that will search for J/sup PC/ hybrid mesons at the Brookhaven MPS-II facility. Such explicitly exotic states are allowed in QCD, and are predicted to be in an accessible mass region by several models. The experiment will investigate the production of exotics in the reaction ..pi../sup /minus//p ..-->.. ..pi../sup /minus//f/sub 1/p. Expected rates and experimental sensitivity to possible hybrid states are discussed. 3 refs. 3 figs.
Date: December 1, 1988
Creator: Chung, S.U.; Fernow, R.; Kirk, H.; Protopopescu, S.D.; Willutzki, H.; Crittenden, R. et al.
Partner: UNT Libraries Government Documents Department

Search for narrow B anti B(. pi. ) states in 16 GeV/c. pi. /sup -/p and 5 GeV/c anti pp interactions

Description: The searches for narrow baryon-antibaryon (B anti B) bound states from two recent experiments carried out at the BNL Multiparticle Spectrometer are reported. First, the results of a search for narrow states in the anti pp, ..lambda..p..pi../sup + -/ and anti pp..pi../sup +/ systems from ..pi../sup -/p interactions at 16 GeV/c are presented. The data come from an experiment carried out by physicists from BNL, Brandeis, CCNY, Southeastern Massachusetts, University of Massachusetts. Next, results are shown of a search for narrow anti pp states from anti pp interactions at 5 GeV/c, an experiment with collaborators from BNL, Brandeis, University of Cincinnati, Florida State University, and Southeastern Massachusetts University.
Date: January 1, 1980
Creator: Chung, S U
Partner: UNT Libraries Government Documents Department

Mass dependent fits of the partial wave analysis of the K/sup +//bar K//sup 0/. pi. /sup /minus// system

Description: We have performed a partial wave analysis of the K/sup +/K/sub S//sup 0/..pi../sup /minus// system produced in the reaction ..pi../sup /minus//p ..-->.. K/sup +//bar K//sup 0/..pi../sup /minus//n at 8 GeV/c. We present the mass dependent fits to the PWA results for the waves J/sup PG/(isobar) = 0/sup /minus/+/(a/sub 0/), 0/sup /minus/+/(K*), 1/sup + +/(a/sub 0/) and 1/sup + +/(K*). 4 refs., 5 figs., 1 tab.
Date: January 1, 1988
Creator: Blessing, S.; Crittenden, R.; Dzierba, A.; Marshall, T.; Teige, S.; Zieminska, D. et al.
Partner: UNT Libraries Government Documents Department

Comparison of PWA results of K[sup +]K[sup o][sub s] [pi][sup [minus]] final states produced in 8 GeV/c K[sup [minus]]p, [pi][sup [minus]] p and [bar p]p interactions

Description: We have performed partial-wave analyses of the K[sup +]K[sup o]s [pi][sup [minus]] system produced in the reactions K[sup [minus]]p [yields] K[sup +]K[sup o]s[pi][sup [minus]], [Lambda]/[Sigma], [pi][sup [minus]]p [yields] K[sup +]K[sup o]s [pi][sup [minus]]n and [bar p]p [yields] K[sup +]K[sup o]s[pi][sup [minus]] X at 8 GeV/c in substantially the same apparatus. We present and compare the results of the analysis of the three reactions in the mass range 1.24 GeV/c[sup 2] < M(KK[pi]) <1.56 GeV/c[sup 2]. In all three reactions the J[sup PG] = O[minus plus], 1[plus minus] and 1[sup ++] waves are the most important. A strong f[sub 1](1285) signal is evident in the [pi] and [bar p] beam data sets but not in the K data. There is evidence of [eta](l280) production, especially in the n and 0 beam data. We find evidence of two O[sup [minus plus]] states in the 1400 MeV/c[sup 2] mass region, but no compelling case for a 1[sup ++] resonance in this region. Finally, the 1[sup [plus minus]] wave in the K beam data is consistent with an h' state below the K*K threshold.
Date: January 1, 1991
Creator: Bar-Yam, Z.; Dowd, J.; Kern, W.; King, E.; Rulon, P. (Massachusetts Univ., North Dartmouth, MA (United States)); Blessing, S. K. et al.
Partner: UNT Libraries Government Documents Department

New higher-statistics study of. pi. /sup -/p. -->. phi phi n and evidence for glueballs

Description: We have obtained 1203 events of the reaction ..pi../sup -/ ..-->.. phi phi n at 22 GeV/c over a small background (approx. 10%). As in our prior experiment the OZI suppression was essentially entirely absent. A partial wave analysis allowing waves up to J = 4 and L = 3 demonstrated that a good fit was obtained with 2 waves, each well described by a Breit-Wigner resonance. The addition of another wave one at a time in turn, resulted in no statistical significance for the wave. Because of the complete breakdown of the OZI suppression, and other characteristics of the data, these two resonances are strong glueball candidates. All the quantum numbers were determined and are given together with the masses and widths. The glueball candidates given provide strong evidence for one or more primary glueballs in this mass region.
Date: January 1, 1982
Creator: Lindenbaum, S.J.; Chan, C. & Etkin, A.
Partner: UNT Libraries Government Documents Department

Diffractive hadronic production of D mesons

Description: A search for charmed D mesons was made with a 217 GeV ..pi../sup -/ beam on a liquid hydrogen target. The Chicago Cyclotron Spectrometer at Fermilab was used to analyze the hadronic decay of a D meson in coincidence with a prompt muon and a recoil proton. A total of 50 +- 12 D/sup + -/ events were observed with equal numbers in the two channels K/sup + -/..pi../sup - +/..pi../sup - +/. Some of the cuts selected diffractive events. When these cuts were removed the signal remained the same, although the background was greatly increased. The Feynman X and angular distributions were consistent with diffractive production. A diffractive model yielded a cross section of (6 to 10) +- 4 ..mu..b.
Date: January 1, 1980
Creator: Koester, L.J.; Alverson, G. & Ascoli, G.
Partner: UNT Libraries Government Documents Department

Hard quark-quark scattering with exclusive reactions

Description: We have begun a program designed to study hard quark-quark scattering with exclusive reactions, focusing on quasi-elastic two-body reactions with all possible quark flavor exchanges. Examples are ..pi../sup -/p ..-->.. ..pi../sup -/p, rho/sup -/p, ..pi../sup +/..delta../sup -/, K/sup +/..sigma../sup -/, or K..lambda... Of the two-body exclusives, only elastic scattering had been measured at such large t previous to our experiment. By comparing the relative importance of different final states, the energy dependence of the production ratios of these states, the prominence of resonances such as rho/sup -/ over background in this region, and measuring polarizations where accessible, we have collected a large body of data on hard scattering in a completely new domain. Previously, essential all short distance QCD tests have been for inclusive processes. We have taken data with both negative and positive incident beam at 10 GeV/c on a hydrogen target and will present the first results, for ..pi../sup -/p ..-->.. ..pi../sup -/p and rho/sup -/p at THETA/sub cm/ = 90/sup 0/, -t = 9 GeV/sup 2//c/sup 2/. The apparatus consists of a magnetic spectrometer, with Cerenkov particle identification, which selects stable charged particles (protons in this case) at high momentum near 90/sup 0/ in the center-of-mass. A large aperture array of PWCs observes the recoil particle or charged decay products. Cross sections are extremely low, approximately a 1 nb/(GeV/c)/sup 2/ for elastic scattering. We will report on a sample of more than 1000 ..pi../sup -/p elastic events, and on rho/sup -/p, where the rho/sup -/ decay distribution was observed. We find a surprisingly large rho/sup -/p cross section in this large momentum transfer region, with rho/sup -/p about half the elastic cross section, and a striking spin alignment of the rho/sup -/.
Date: July 19, 1984
Creator: Barton, D.S.; Bunce, G.M.; Carroll, A.S.; Makdisi, Y.I.; Baller, B.; Blazey, G.C. et al.
Partner: UNT Libraries Government Documents Department

pi. /sup -/p. -->. K/sub s//sup 0/K/sub s//sup 0/n at 22 Gev/c and a systematic study of the 2/sup + +/ and 0/sup + +/ meson spectrum

Description: A coupled channel analysis has been carried out using amplitudes of the K/sub s//sup 0/K/sub s//sup 0/ system produced in the reaction ..pi../sup -/p ..-->.. K/sub s//sup 0/K/sub s//sup 0/n at 22 Gev/c, which contained about 40,000 events in the low-t region (absolute value of t-tmin < 0.1 Gev/sup 2/). The I/sup G/ = 0/sup +/, J/sup PC/ = 0/sup + +/, 2/sup + +/, 4/sup + +/ amplitudes from this analysis is considered, together with available data from other experiments in channels with the same quantum numbers in order to determine which 0/sup + +/ and 2/sup + +/ isoscalar mesons have significant pseudoscalar-pseudoscalar couplings. It is found that we need one pole for the 4/sup + +/ amplitudes while the 2/sup + +/ needs five poles and the 0/sup + +/ needs 7 poles.
Date: June 23, 1987
Creator: Longacre, R.S.; Etkin, A.; Foley, K.J.; Love, W.A.; Morris, T.W.; Platner, E.D. et al.
Partner: UNT Libraries Government Documents Department

Anomalous low mass e/sup +/e/sup -/ pair production in 17 GeV/c. pi. /sup -/p collisions

Description: An experiment was performed at the Multiparticle Spectrometer using 17 GeV/c ..pi../sup -/ from the BNL AGS, triggering upon inclusive e/sup +/e/sup -/ production. Electron identification was based on two transition radiator detectors and lead-scintillator shower detectors. Good acceptance for the e/sup +/e/sup -/ pair covered the region x/sub F/ &gt; 0.3 for all p/sub T/ and pair masses. Charged particles and photons associated with the e/sup +/e/sup -/ pair are detected over a large solid angle. e/sup +/e/sup -/ pairs of mass up to 1.2 GeV/c/sup 2/ were produced. A clear peak due to rho, ..omega.. ..--&gt;.. e/sup +/e/sup -/ is observed. For e/sup +/e/sup -/ masses below the rho, ..omega.., an excess of events is found over those expected from known sources such as eta ..--&gt;.. e/sup +/e/sup -/..gamma.. and ..omega.. ..--&gt;.. e/sup +/e/sup -/..pi../sup 0/. This anomalous excess is more strongly produced at small x/sub F/. The structure of events containing anomalous e/sup +/e/sup -/ pairs is reported in an attempt to elucidate their origin. In particular, effective mass distributions of e/sup +/e/sup -/..gamma.., e/sup +/e/sup -/..pi../sup 0/, e/sup +/e/sup -/ charged hadrons are presented.
Date: January 1, 1980
Creator: Abshire, G; Adams, M & Brown, C
Partner: UNT Libraries Government Documents Department

A program of quark-gluon' spectroscopy at BNL

Description: The current status and future prospects are given of the quark-gluon spectroscopy, and a multi-year experimental program at BNL is described, consisting of experiments E771, E818 and E852, which address the question of missing quarkonia in the SU(3) family of mesons and the existence of exotic hadrons with gluonic degrees of freedom. 23 refs., 8 figs., 8 tabs.
Date: December 1, 1989
Creator: Chung, S.U.
Partner: UNT Libraries Government Documents Department

Resonances in the phi phi system and glueballs

Description: The mass spectrum and the final partial wave analysis of the OZI forbidden reaction ..pi../sup -/p ..-->.. phi phi n are shown. A unique good fit solution was found which selected only three I/sup G/J/sup PC/ = 0/sup +/2/sup 2 +/ waves with J/sub z/sup e+a/ = 0/sup -/ in the Gottfried Jackson frame. The partial wave amplitude and phase behavior clearly indicated resonant behavior. A three-pole K-matrix fit corresponded to a good fit whereas a two-pole fit was rejected. It is found that the disconnected Zweig diagram is due to a ..pi../sup +/ annihilating the incident ..pi../sup -/. A partial wave analysis of the background in the region slightly above the phi mass for the K/sup +/K/sup -/ pair is given. The selective breakdown of the OZI suppressiion and the different nature of the OZI-allowed background are explained in the context of QCD by attributing the production of these states to 1-3 primary glueballs. 4 refs., 5 figs. (LEW)
Date: January 1, 1985
Creator: Lindenbaum, S.J.
Partner: UNT Libraries Government Documents Department

Measurement of the analyzing power for pion proton elastic scattering between 471 and 687 MeV/c

Description: The analyzing power, A/sub N/, has been measured for ..pi../sup + -/p..--> pi../sup + -/p at 471, 547, 625, and 687 MeV/c in an angular range corresponding to -0.9 less than or equal to cos theta/sub cm/ less than or equal to 0.8. A polarized proton target with polarization axis normal to the scattering plane was used. The scattered pion and recoil proton were detected in coincidence, using a magnetic spectrometer and a wire chamber/scintillator array, except in cases where one of the particles was kinematically inaccessible. Statistical uncertainties in the data are as low as 0.02; systematic uncertainties are estimated to be less than 3%. The ..pi../sup -/p data are characterized by large values of analyzing power, and rapid variations in the angular distribution with incident momentum. The measurements are compared with the results of existing partial wave analysis.
Date: June 1, 1985
Creator: Mokhtari-Amirmajdi, A.
Partner: UNT Libraries Government Documents Department