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Some recent results on meson spectroscopy

Description: A comparative survey of established meson states with the predictions of a q anti q (quarkonium) model by Godfrey and Isgur shows that most meson states are well described, from pion to UPSILON(6S). However, a number of states in the light- quark isoscalar sector are not predicted at all in their model, pointing to a need for glueballs, hybrids and multi-quark states to fully account for recently reported meson states. 48 refs.
Date: June 1, 1987
Creator: Chung, S.U.
Partner: UNT Libraries Government Documents Department

The q q meson states with J sup PC = 2 sup ++ and 0 sup ++

Description: The lowest mesons made up of a light quark and a strange quark produced from a K beam show a good agreement with expectations of the quark model. This good agreement leads to the prediction of the light isoscalar and isovector states and the isoscalar s{bar s} states. Except for one mystery The X(1590) the 2{sup ++} states seems to be well described by the expected ideally mixed q{bar q} states up to 2. 0 GeV. Above 2.0 GeV a new degree of freedom seems to be excited with respect to the breakdown of the OZI rule in production of 2{sup ++} resonances that decay into {phi}{phi}. This is to be contrasted with the situation for the O{sup ++} isoscalar states which seems to show a new degree of freedom for its mesons in its ground state. One might conclude that since the O{sup ++} glueball is predicted by lattice calculations to be degenerate with the s{bar s} O{sup ++} meson, that the very unusual assortment of isoscalar O{sup ++} mesons are due to glueball mixing.
Date: September 26, 1991
Creator: Longacre, R.S.
Partner: UNT Libraries Government Documents Department

Beauty physics at Fermilab fixed target energies

Description: The very high luminosities (>>10/sup 32/cm/sup /minus/2/sec/sup /minus/1/) available in the Fermilab fixed target experimental areas offer immediate opportunities for producing large samples (>10/sup 8/ of B hadrons in individual experiments. The possibilities of accumulating large samples of B decays are limited by experimental techniques and trigger strategies and not by available luminosity. At the present time one experiment, E771, is approved to begin B physics experimentation and several other experimental possibilities are being discussed. Some of the problems and the potential of B experiments at fixed target energies as B factories are discussed.
Date: April 1, 1988
Creator: Cox, B.
Partner: UNT Libraries Government Documents Department

Nucleon-nucleon theory and phenomenology. Progress report and renewal proposal

Description: Progress is outlined on five inter-related subprojects: (1) derivation of the intermediate range nucleon-nucleon interaction with the new dramatically altered ..pi pi.. s-wave interaction and using a new method that utilizes much shorter and simpler analytic continuation through the unphysical region that lies between the ..pi..N and ..pi pi.. physical regions of the N anti N ..-->.. ..pi pi.. amplitude (with significantly improved accuracy for the nucleon-nucleon interaction); (2) construction of a short range phenomenological potential that, with the theoretical part mentioned above, gives a precise fit to the nucleon-nucleon data and is parameterized for easy use in nucleon calculations; (3) phase shift analyses of the world data below 400 MeV, especially the large amount of very precise data below 20 MeV and the new data near 55 MeV that have never been analyzed properly, and determining which phases are given by theory at which energies; (4) the introduction of our K-matrix formulation of the Optimal Polynomial Expansion in order to accelerate convergence of the partial wave series at LAMPF energies; and (5) setting up of a cooperatively evaluated and verified permanent nucleon-nucleon data bank in the 0 to 1200 MeV range that can be used by all nucleon-nucleon researchers (or anyone else) via Telenet dial-in and by means of a published compendium. (WHK)
Date: January 1, 1981
Creator: Signell, P.
Partner: UNT Libraries Government Documents Department

Trends in exotic-atom research

Description: An attempt was made to analyze the trends in the development of exotic-atom research on the basis of a recently compiled bibliography. The analysis of nearly 4000 publications demonstrated that: (1) exotic atoms are nuclear probes used in every field of physics, from the test of quantum electrodynamics (QED) to chemical physics, to materials sciences; (2) the role of nuclear and atomic physics in exotic atom research is decreasing (although it is still significant), while that of materials sciences and chemial physics is exponentially increasing; and (3) prior to 1980 most investigators were mainly interested in atoms with negative muons, while during the last few years the positive muon (..mu..SR) studies have dominated exotic atom research.
Date: January 1, 1983
Creator: Lambrecht, R.M. & Horvath, D.
Partner: UNT Libraries Government Documents Department

Recent measurements of the average lifetime of hadrons containing B-quarks from PEP experiments at SLAC (Stanford Linear Accelerator Center)

Description: Recent precise results from several experiments have confirmed the early evidence that the lifetime of hadrons containing B-quarks is rather long, implying that the third generation of quarks is more decoupled from the first two than the second is from the first. The average of the measurements performed by the experiments at PEP is 1.08 +- 0.13 ps.
Date: May 1, 1987
Creator: Camporesi, T.
Partner: UNT Libraries Government Documents Department

Charm lifetime measurements from TASSO

Description: Recent measurements by TASSO of the lifetimes of charmed mesons is reviewed. The lifetime reported for the D/sub s/ meson utilizes the entire data sample collected. The lifetime of the neutral charmed meson, D/sup o/, is from a subsample of the total data set. Special emphases is given to the experimental procedures used.
Date: October 9, 1987
Creator: Forden, G.E.
Partner: UNT Libraries Government Documents Department

Nucleon decay experiments: status and prospects

Description: We survey the current status and future prospects of experiments to search for nucleon decay. Results from current experiments are summarized, and the background rejection capabilities of various techniques are described. We discuss the prospects for improved sensitivity in the new experiments that are now coming into operation, and the opportunities for the next generation of detectors. 33 refs., 2 figs., 4 tabs.
Date: January 1, 1986
Creator: Ayres, D.S.; Beier, E.W.; D'Ettorre Piazzoli, B.; Ernwein, J.; Gaisser, T.K.; Seidel, S. et al.
Partner: UNT Libraries Government Documents Department

The meson spectrum between 1 and 2 GeV: Gluonic states and other exotica

Description: Present understanding of the meson spectrum is reviewed, with special attention on the search for gluonic states. Experimental progress has resulted in several paradoxes indicating states outside the {bar q}q spectrum of the nonrelativistic quark model. 59 refs., 1 fig., 2 tabs.
Date: July 20, 1990
Creator: Chanowitz, M.S.
Partner: UNT Libraries Government Documents Department

Asymmetry measurements in PP elastic scattering during polarized beam acceleration up to 4. 4 GeV/c

Description: This is a brief report on the first measurement of the continuous momentum dependence of the analyzing power in proton-proton elastic scattering during polarized beam acceleration from 1.1 to 4.4 GeV/c. The measurement was done in the KEK-PS tunnel using an internal polyethylene thread target. The momentum bin size ranges from 5 to 18 MeV/c. Statistical uncertainty of the analyzing power is typically 0.5% per momentum bin. A small narrow structure has been observed at the incident proton momentum of 1.23 GeV/c. 2 refs., 4 figs.
Date: January 1, 1989
Creator: Shimizu, H.; Yoshida, H.; Ohnuma, H.; Kobayashi, Y.; Kobayashi, K.; Nakagawa, T. et al.
Partner: UNT Libraries Government Documents Department

Backgrounds to the detection of two-body hadronic B decays

Description: We consider backgrounds to the detection of the two-body hadronic decay modes of neutral B mesons and baryons. The largest background is due to the correlated production of pairs of high-p/sub T/ hadrons in the target, but this can be adequately rejected provided the experimental apparatus has sufficient resolution in mass and decay vertex. Another possible source of background arises from the production and decay of charmed and strange particles. Since these particles can travel considerable distances before decaying, they can give rise to backgrounds which may not be rejectable by means of vertex cut. We have simulated several backgrounds from charm, and we find them to be small compared to the expected level of signal. 8 refs., 1 fig., 2 tabs
Date: January 8, 1988
Creator: Kaplan, D.M.; Peng, Jen-Chieh; Abrams, G.S. & Stockdale, I.E.
Partner: UNT Libraries Government Documents Department

Search for stable quarks produced by the Tevatron

Description: An experiment has been run at the Tevatron to search for stable fractionally charged particles (i.e., quarks) produced by the 800 GeV/c proton beam. The experiment was performed in two phases. In the first run, 1.0 x 10/sup 15/ protons passed through a series of four mercury targets which were distributed among several lead degraders. The lead degraders were arranged so that fractionally charged particles over a wide range of production angles, masses, and energies would stop in the mercury targets. A small amount of this mercury has been analyzed for fractional charge in an automated Millikan apparatus. A second run, which had an integrated proton intensity of 4.1 x 10/sup 13/, used liquid nitrogen tanks to stop any fractionally charged particles produced when the proton beam interacted in an upstream lead target. In the four tanks, electrically charged gold-plated glass fibers attracted and then trapped any fractional charges which were stopped in the liquid nitrogen. After the exposure, the wires were moved through small beads of mercury in which the gold was dissolved. One of these small beads of mercury also has been analyzed in the same Millikan apparatus. The results from the first run show that the upper limit for quark production is less than 1 x 10/sup -6/ quarks per proton interaction at 90% confidence limit, the results from the second run show that the upper limit is 9.3 x 10/sup -10/. The analysis of the mercury is continuing.
Date: June 1, 1986
Creator: Matis, H.S.; Bland, R.W.; Hahn, A.A.; Hodges, C.L.; Lindgren, M.A.; Pugh, H.G. et al.
Partner: UNT Libraries Government Documents Department

Search for the violation of time-reversal invariance in K/sub. mu. 3/ decays

Description: The polarization of the ..mu../sup +/ from the decays K/sup 0//sub L/ ..-->.. ..pi../sup -/..mu../sup +/..nu.. and K/sup +/ ..-->.. ..pi../sup 0/..mu../sup +/..nu.. was measured. The transverse polarization forbidden by time reversal invariance is (1.85 +- 3.60) x 10/sup -3/ based on the final data sample of thirty-four million events. This null result places constraints on certain models of CP-violation through the exchange of Higgs bosons.
Date: August 1, 1981
Creator: Morse, W.M.; Leipuner, L.B.; Larsen, R.C.; Blatt, S.R.; Campbell, M.K.; Adair, R.K. et al.
Partner: UNT Libraries Government Documents Department

Gluonium candidates from hadronic and e/sup +/e/sup -/ interactions

Description: The experimental approaches exploited in the search for gluonia that are deemed most promising are briefly described, both in hadron-hadron collisions and heavy quarkonium decay. The presently available evidence is summarized for those states that have been claimed as possible gluonia. Proceeding in the order of lowest-mass expectation, categorization is done only in terms of definitive (or putative) J/sup PC/ assignments. 51 refs., 16 figs., 3 tabs. (LEW)
Date: December 1, 1985
Creator: Heusch, C.A.
Partner: UNT Libraries Government Documents Department

Implications for supersymmetry of the CERN monojets

Description: Results of a comprehensive study of supersymmetric processes which could give monojet events similar to those observed at the CERN Sp anti pS are presented. If supersymmetry is to be the explanation of the monojets, strict bounds are obtained on possible supersymmetric masses. 15 references.
Date: January 1, 1985
Creator: Haber, H.E.
Partner: UNT Libraries Government Documents Department

High neutral transverse energy events at the CERN ISR

Description: The CERN-Oxford-Rockefeller (COR) collaboration has obtained neutral transverse energy, E/sub T//sup 0/, spectra in pp collisions at ..sqrt..s = 30.5, 45.0, and 62.3 GeV. Evidence is presented for the increasing dominance of 2-jet events as E/sub T//sup 0/ increases.
Date: January 1, 1983
Creator: Cox, P. T.
Partner: UNT Libraries Government Documents Department

Direct photon experiment at POLEX

Description: Significant contribution of the gluons to the proton spin has been suggested by several authors to explain the recent EMC results on the spin dependent structure function of proton. Direct photon measurements at large transverse momentum in pp reactions with pure initial helicity states is proposed in this paper in order to study spin dependent gluon structure function. 8 refs., 3 figs., 1 tab.
Date: January 1, 1989
Creator: Ohashi, Y.
Partner: UNT Libraries Government Documents Department

Preparing the database for future CP violation measurements with B-mesons at e/sup +/e/sup -/ machines

Description: We consider the contribution of e/sup /plus//e/sup /minus// machines to the measurement of CP violation in the B systems. Energy regions from the GAMMA(4S) to the Z/degree/ are considered, problems and prospects at each energy are reviewed.
Date: April 7, 1988
Creator: Byers, N.; Foley, K.; Goldberg, M.; Mistry, N & Shipsey, I.
Partner: UNT Libraries Government Documents Department

The search for the H dibaryon with the BNL 2. 0 GeV/c kaon beam

Description: The status is given for two experiments being carried out to search for evidence of the H dibaryon. BNL experiments E813 and E836 will use the new 2 GeV/c kaon beam line. The former has recently begun data taking. They cover complementary regions of mass-sensitivity and promise to provide sensitive tests of the existence of the H. 12 refs.
Date: January 1, 1991
Creator: Quinn, B.P.
Partner: UNT Libraries Government Documents Department

Triple-jet structures in proton-proton interactions

Description: In this experiment, which uses a superconducting solenoid at the CERN ISR, a large sample of two-jet events produced in proton-proton collisions at 62 GeV centre-of-mass energy has been examined for evidence of three-jet structures; that is, for the presence of events in which three particle jets can be separately identified at large transverse momenta relative to the initial proton directions, there also being spectator jets following these directions, making five jets in all. Such three-jet events are expected to be produced by gluon bremsstrahlung, as has been observed in the e/sup +/e/sup -/ case, but several additional mechanisms are expected in the case of hadronic collisions. The three-jet events are identified by cluster analysis, the particles of each event being sorted into the best three-cluster and two-cluster combinations. Results are briefly described. (WHK)
Date: July 1, 1981
Creator: Angelis, A. L.S.; Besch, H. J. & Blumenfeld, B. J.
Partner: UNT Libraries Government Documents Department