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2. Strange meson production ine+e− annihilation

Author

Braunschweig, W., Gerhards, R., Kirschfink, F. J., Martyn, H. -U., Fischer, H. M., Hartmann, H., Hartmann, J., Hilger, E., Jocksch, A., Wedemeyer, R., Foster, B., Martin, A. J., Barreiro, F., Bernardi, E., Chwastowski, J., Eskreys, A., Gather, K., Genser, K., Hultschig, H., Joos, P., Kowalski, H., Ladage, A., Löhr, B., Lüke, D., Mättig, P., Notz, D., Pawlak, J. M., Pösnecker, K. -U., Ros, E., Trines, D., Walczak, R., Wolf, G., Kolanoski, H., Kracht, T., Krüger, J., Lohrmann, E., Poelz, G., Zeuner, W., Hassard, J., Shulman, J., Su, D., Tomalin, I., Watson, A., Cases, G., Hervas, L., Leites, A., del Peso, J., de Trocóniz, J. Fdez, Bowler, M. G., Burrows, P. N., Cashmore, R., Veitch, M. E., Hart, J. C., Saxon, D. H., Brandt, S., Holder, M., Labarga, L., Eisenberg, Y., Karshon, U., Mikenberg, G., Montag, A., Revel, D., Ronat, E., Shapira, A., Wainer, N., Yekutieli, G., Caldwell, A., Muller, D., Ritz, S., Strom, D., Takashima, M., Wu, Sau Lan, and Zobernig, G.

Abstract

The full TASSO data have been used to study the inclusive production of strange mesons ine+e- annihilations. Differential and total cross sections have been measured in the centre of mass energy range 14 to 44 GeV forK0, " and 34.5 to 44 GeV forK*± (892). We have investigated the strange meson production properties in jets by studying the rapidity andpt2 distributions as well as the evolution of the multiplicities as a function of the event sphericity. We find no evidence that the strange meson yields increase with increasing sphericity faster than the total charged multiplicity.

Published
1990
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3. Experimental study of the orientation of three-jet events ine+e− annihilation at PETRA

Author

Braunschweig, W., Gerhards, R., Kirschfink, F. J., Martyn, H. -U., Fischer, H. M., Hartmann, H., Hartmann, J., Hilger, E., Jocksch, A., Wedemeyer, R., Foster, B., Martin, A. J., Barreiro, F., Bernardi, E., Chwastowski, J., Eskreys, A., Gather, K., Genser, K., Hultschig, H., Joos, P., Körner, J., Kowalski, H., Ladage, A., Löhr, B., Lüke, D., Mättig, P., Notz, D., Pawlak, J. M., Pösnecker, K. -U., Ros, E., Trines, D., Walczak, R., Wolf, G., Kolanoski, H., Kracht, T., Krüger, J., Lohrmann, E., Poelz, G., Zeuner, W., Hassard, J., Shulman, J., Su, D., Tomalin, I., Watson, A., Cases, G., Hervas, L., Leites, A., del Peso, J., Bowler, M. G., Burrows, P. N., Cashmore, R., Veitch, M. E., Hart, J. C., Saxon, D. H., Brandt, S., Holder, M., Labarga, L., Eisenberg, Y., Karshon, U., Mikenberg, G., Montag, A., Revel, D., Ronat, E., Shapira, A., Wainer, N., Yekutieli, G., Caldwell, A., Muller, D., Ritz, S., Strom, D., Takashima, M., Wu, Sau Lan, and Zobernig, G.

Abstract

The full TASSO data have been used to study the orientation of three-jet events ine+e- annihilation. The polar angle distributions of the normal to the three-jet plane as well as the polar angle distribution of the most energetic jet have been measured as a function of the thrust cut-off used to select the three-jet sample. The data corrected for radiation and detector effects are compared to QCD predictions and fair agreement is found. As a consistency check we also present measurements of the azimuthal correlations between the lepton and hadron planes. A significant azimuthal dependence is found, consistent again with the QCD predictions.

Published
1990
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4. Production and decay of charmed mesions ine+e− annihilation at <img src="/fulltext-image.asp?format=htmlnonpaginated&src=U564651613106L43_html\10052_2005_Article_BF01415550_TeX2GIFIE1.gif" border="0" alt=" $$\sqrt s > 28$$ " />

Author

Braunschweig, W., Gerhards, R., Kirschfink, F., Martyn, H., Fischer, H., Hartmann, H., Hartmann, J., Hilger, E., Jocksch, A., Wedemeyer, R., Foster, B., Martin, A., Bernardi, E., Chwastowski, J., Eskreys, A., Gather, K., Genser, K., Hultschig, H., Joos, P., Kowalski, H., Ladage, A., Löhr, B., Lüke, D., Mättig, P., Notz, D., Pawlak, J., Pösnecker, K., Ros, E., Trines, D., Walczak, R., Wolf, G., Kolanoski, H., Kracht, T., Krüger, J., Lohrmann, E., Poelz, G., Zeuner, W., Galik, R., Hassard, J., Shulman, J., Su, D., Tomalin, I., Watson, A., Barreiro, F., Leites, A., Peso, J., Bowler, M., Burrows, P., Veitch, M., Forden, G., Hart, J., Saxon, D., Brandt, S., Holder, M., Eisenberg, Y., Karshon, U., Mikenberg, G., Montag, A., Revel, D., Ronat, E., Shapira, A., Wainer, N., Yekutieli, G., Caldwell, A., Muller, D., Ritz, S., Strom, D., Takashima, M., Wu, Sau, and Zobernig, G.

Abstract

We report on a study of inclusive production ofD*± mesons ine+e− annihilation at c.m. energies between 28 and 46.8 GeV using the TASSO detector at the PETRA storage ring. A hardD*± energy spectrum is measured with a maximum nearED*±≃0.6Ebeam. The measured cross section ratio " indicates thatD* production accounts for a large fraction of the observed charm production. Two complementary methods have been used to determine the forward-backward asymmetry of charm pair production due to electroweak interference. Combining both measurements the product of the axial vector couplings of the electron and the charm quark to the weak neutral current was determined to begAegAc=−(0.276±0.073), in agreement with the standard model prediction of −0.25. Using a sample of reconstructedD*± mesons, the relative strength of the strong interaction coupling of thec quark compared to that of an average of all flavours is measured as αs(c)/αs(all)=0.91±0.38±0.15, consistent with the coupling constant being flavour independent. An update of ourD0 lifetime measurement is presented, based on a considerable increase in statistics, the final result being ".

Published
1989
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5. Pion, kaon and proton cross sections ine+e− annihilation at 34 GeV and 44 GeV c.m. energy

Author

Braunschweig, W., Gerhards, R., Kirschfink, F. J., Martyn, H. -U., Bock, B., Fischer, H. M., Hartmann, H., Hartmann, J., Hilger, E., Jocksch, A., Wedemeyer, R., Foster, B., Martin, A. J., Sephton, A. J., Barreiro, F., Bernardi, E., Chwastowski, J., Eskreys, A., Gather, K., Genser, K., Hultschig, H., Joos, P., Kowalski, H., Ladage, A., Lohr, B., Lüke, D., Mattig, P., Notz, D., Pawlak, J. M., Pösnecker, K. -U., Ros, E., Trines, D., Walczak, R., Wolf, G., Kolanoski, H., Gerhardt, W., Kracht, T., Krasemann, H. L., Krüger, J., Lohrmann, E., Poelz, G., Rehders, P., Tysarczyk, G., Winand, C., Zeuner, W., Binnie, D. M., Hassard, J., Shulman, J., Su, D., Leites, A., del Peso, J., Balkwill, C., Bowler, M. G., Burrows, P. N., Cashmore, R., Heath, G. P., Ratoff, P. N., Silvester, I. M., Tomalin, I. R., Veitch, M. E., Forden, G. E., Hart, J. C., Saxon, D. H., Brandt, S., Holder, M., Labarga, L., Eisenberg, Y., Karshon, U., Mikenberg, G., Montag, A., Revel, D., Ronat, E., Shapira, A., Wainer, N., Yekutieli, G., Caldwell, A., Muller, D., Ritz, S., Strom, D., Takashima, M., Wicklund, E., Lan Wu, Sau, and Zobernig, G.

Abstract

The inclusive production of p± andK± mesons and of protons and antiprotons ine+e- annihilations has been measured at 34 GeV and 44 GeV center of mass energy; in addition p± mesons have been measured at 44 GeV c.m. energy. Differential cross sections and particle yields are given. At 34 GeV average multiplicities are: $$\begin{gathered} \left\langle {n\left( {\pi ^ \pm } \right)} \right\rangle = 10.9 \pm 0.5,\left\langle {n\left( {K^ \pm } \right)} \right\rangle = 1.76 \pm 0.20, \hfill \\ \left\langle {n\left( {p + \bar p} \right)} \right\rangle = 0.67 \pm 0.06 \hfill \\ \end{gathered} $$ and at 44 GeV: $$\left\langle {n\left( {\pi ^ \pm } \right)} \right\rangle = 11.1 \pm 0.5,\left\langle {n\left( {\pi ^0 } \right)} \right\rangle = 5.4 \pm 1.0.$$

Published
1989
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6. A study of jets fromb quarks produced ine+e− annihilations at <img src="/fulltext-image.asp?format=htmlnonpaginated&src=M158034825661433_html\10052_2005_Article_BF01565125_TeX2GIFIE1.gif" border="0" alt=" $$

Author

Braunschweig, W., Gerhards, R., Kirschfink, F. J., Martyn, H. -U., Bock, B., Fischer, H. M., Hartmann, H., Hartmann, J., Hilger, E., Jocksch, A., Wedemeyer, R., Foster, B., Martin, A. J., Sephton, A. J., Bernardi, E., Chwastowski, J., Eskreys, A., Gather, K., Genser, K., Hultschig, H., Joos, P., Kowalski, H., Ladage, A., Löhr, B., Lüke, D., Mattig, P., Notz, D., Pawlak, J., Pösnecker, K. -U., Ros, E., Schütte, W., Trines, D., Walczak, R., Wolf, G., Kolanoski, H., Kracht, T., Krüger, J., Lohrmann, E., Poelz, G., Zeuner, W., Belk, A. T., Binnie, D. M., Hassard, J. F., Shulman, J., Su, D., Barreiro, F., Leites, A., del Peso, J., Balkwill, C., Bowler, M. G., Burrows, P. N., Cashmore, R. J., Heath, G. P., Ratoff, P., Silvester, I. M., Tomalin, I., Veitch, M. E., Yelton, J. M., Lloyd, S. L., Forden, G. E., Hart, J. C., Saxon, D. H., Brandt, S., Holder, M., Labarga, L., Eisenberg, Y., Karshon, U., Mikenberg, G., Montag, A., Revel, D., Ronat, E., Shapira, A., Wainer, N., Yekutieli, G., Muller, D., Ritz, S., Strom, D., Takashima, M., Wu, Sau Lan, and Zobernig, G.

Abstract

Ab enrichment technique using the longB lifetime has been developed, by which ∼600 hadronic events with >65%b purity are obtained. The properties of the associated jets are studied, with comparisons made between them and those in hadronic data in whichb quarks make up only 10% of the total, and jets in Monte Carlo events. The distributions in rapidity and multiplicity yield two new determinations of the fragmentation variablez forb hadrons and confirm that theb fragmentation function is hard. We also present the first measurement of the relative strength of the strong interaction coupling of theb quark compared with the average of all flavours.

Published
1989
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7. Bose-Einstein correlations observed ine+e− annihilation at a centre of mass energy of 34 GeV

Author

Althoff, M., Braunschweig, W., Kirschfink, F. J., Martyn, H. -U., Rosskamp, P., Wallraff, W., Eisenmann, J., Fischer, H. M., Hartmann, H., Jocksch, A., Knop, G., Kolanoski, H., Kück, H., Mertens, V., Wedemeyer, R., Foster, B., Wood, A., Bernardi, E., Eskreys, A., Fohrmann, R., Gather, K., Hultschig, H., Joos, P., Karshon, U., Klima, B., Kötz, U., Kowalski, H., Ladage, A., Löhr, B., Lüke, D., Mättig, P., Notz, D., Revel, D., Shapira, A., Trines, D., Tymieniecka, T., Wolf, G., Zeuner, W., Hilger, E., Kracht, T., Krasemann, H. L., Lohrmann, E., Poelz, G., Pösnecker, K. -U., Binnie, D. M., Dornan, P. J., Garbutt, D. A., Jenkins, C., Jones, W. G., Sedgbeer, J. K., Su, D., Thomas, J., Wan Abdullah, W. A. T., Barreiro, F., Labarga, L., Ros, E., Bowler, M. G., Bull, P., Cashmore, R. J., Dauncey, P., Devenish, R., Hawkes, C. M., Heath, G., Mellor, D. J., Ratoff, P., Lloyd, S. L., Forden, G. E., Hart, J. C., Hasell, D. K., Saxon, D. H., Brandt, S., Dittmar, M., Holder, M., Kreutz, G., Neumann, B., Eisenberg, Y., Montag, A., Mikenberg, G., Mir, R., Ronat, E., Yekutieli, G., Baranko, G., Caldwell, A., Cherney, M., Hildebrandt, M., Izen, J. M., Mermikides, M., Ritz, S., Strom, D., Takashima, M., Venkataramania, H., Wicklund, E., Wu, Sau Lan, and Zobernig, G.

Abstract

Bose-Einstein correlations between pairs of charged particles produced ine+e- annihilation into hadronic final states have been studied as a function ofQ2, the relative momentum squared of the two particles in their centre of mass, and as functions of various pairs of kinematic variables. The observed Bose-Einstein enhancement reveals correlation between the position and time of particle emission, and the space-time structure of the source is shown to differ from that of a pion fireball. While most features of the data are well accounted for in terms of the space-time structure of a simple string model, the correlations are better described by the simple function 1+ae-ßQ2. The implications of this result are discussed. The principal features of three particle correlations are explained in terms of the structure of the source inferred from the observed two particle correlations.

Published
1986
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8. Particle correlation observed ine+e− annihilations into hadrons at c.m. Energies between 29 and 37 GeV

Author

Althoff, M., Braunschweig, W., Kirschfink, F. J., Martyn, H. U., Rosskamp, R., Siebke, H., Wallraff, W., Eisenmann, J., Fischer, H. M., Hartmann, H., Jocksch, A., Knop, G., Kolanoski, H., Kück, H., Mertens, V., Wedemeyer, R., Foster, B., Wood, A., Bernardi, E., Eisenberg, Y., Eskreys, A., Fohrmann, R., Gather, K., Hultschig, H., Joos, P., Klima, B., Kötz, U., Kowalski, H., Lagage, A., Löhr, B., Lüke, D., Mättig, P., Mikenberg, G., Notz, D., Revel, D., Trines, D., Tymieniecka, T., Wolf, G., Zeuner, W., Hilger, E., Kracht, T., Krasemann, H. L., Lohrmann, E., Poelz, G., Pösnecker, K. U., Binnie, D. M., Dornan, P. J., Garbutt, D. A., Jenkins, C., Jones, W. G., Sedgbeer, J. K., Su, D., Thomas, J., Wan Abdullah, W. A. T., Barreiro, F., Labarga, L., Ros, E., Bowler, M. G., Bull, P., Cashmore, R. J., Dauncey, P., Devenish, R., Hawkes, C. M., Heath, G., Mellor, D. J., Ratoff, P., Lloyd, S. L., Bell, K. W., Forden, G. E., Hart, J. C., Hasell, D. K., Saxon, D. H., Brandt, S., Dittmar, M., Holder, M., Kreutz, G., Neumann, B., Duchovni, E., Karshon, U., Montag, A., Mir, R., Ronat, E., Yekutieli, G., Shapira, A., Baranka, G., Caldwell, A., Cherney, M., Hildebrandt, M., Izen, J. M., Mermikides, M., Ritz, S., Strom, D., Takashima, M., Venkataramania, H., Wicklund, E., Wu, S. L., and Zobernig, G.

Abstract

We have studied the correlations between charged particles produced ine+e- annihilations into hadrons at c.m. energies between 29 and 37 GeV. We have analysed the correlations between the charged multiplicities of the jets and the two particle rapidity and charge correlations. No evidence for correlations between the multiplicities of the two jets is found. Two particle short range rapidity and charge correlations are observed, indicating that particles cluster in rapidity and that their charges compensate locally. An extensive study of these correlation effects by QCD Monte Carlo calculations was performed. Evidence for charge correlations due to Bose-Einstein statistics is also observed.

Published
1985
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9. A detailed study of strange particle production ine+e− annihilation at high energy

Author

Althoff, M., Braunschweig, W., Kirschfink, F. J., Lübelsmeyer, K., Martyn, H. -U., Rosskamp, P., Schmitz, D., Siebke, H., Wallraff, W., Eisenmann, J., Fischer, H. M., Hartmann, H., Joksch, A., Knop, G., Kolanoski, H., Kuck, H., Mertens, V., Wedemeyer, R., Foster, B., Eskreys, A., Gather, K., Hildebrandt, M., Hultschig, H., Joos, P., Kötz, U., Kowalski, H., Ladage, A., Löhr, B., Lüke, D., Mättig, P., Notz, D., Nowak, R. J., Pyrlik, J., Ronat, E., Rushton, M., Schütte, W., Trines, D., Tymieniecka, T., Wolf, G., Yekutieli, G., Xiao, Ch., Fohrmann, R., Hilger, E., Kracht, T., Krasemann, H. L., Leu, P., Lohrmann, E., Pandoulas, D., Poelz, G., Pösnecker, K. U., Wiik, B. H., Beuselinck, R., Binnie, D. M., Campbell, A. J., Dornan, P. J., Garbutt, D. A., Jenkins, C., Jones, T. D., Jones, W. G., McCardle, J., Sedgbeer, J. K., Thomas, J., Abdullah, W. A. T. Wan, Bell, K. W., Bowler, M. G., Bull, P., Cashmore, R. J., Clarke, P. E. L., Dauncey, P., Devenish, R., Grossmann, P., Hawkes, C. M., Lloyd, S. L., Mellor, D., Youngman, C., Forden, G. E., Hart, J. C., Harvey, J., Hasell, D. K., Saxon, D. H., Woodworth, P. L., Barreiro, F., Brandt, S., Dittmar, M., Holder, M., Kreutz, G., Neumann, B., Duchovni, E., Eisenberg, Y., Karshon, U., Mikenberg, G., Mir, R., Revel, D., Shapira, A., Baranko, G., Caldwell, A., Cherney, M., Izen, J. M., Mermikides, M., Ritz, S., Rudolph, G., Strom, D., Takashima, M., Venkataramania, H., Wicklund, E., Wu, Sau Lan, and Zobernig, G.

Abstract

Results onK0 and ? production ine+e- annihilation at c.m. energies of 14, 22 and 34 GeV are presented. The shape of theK0 and ? differential cross sections are very similar to each other and to those of p±,K± and ". Scaling violations are observed forK0 production. We obtain a value for the probability to produce strange quark-antiquark pairs relative to that to produce up or down quark-antiquark pairs of 0.35±0.02±0.05. The value ofRh=s(e+e-?hX)/sµµ is shown to rise steadily with c.m. energy for all particle species. At 34 GeV we find 1.48±0.05K0 and 0.31±0.03 ? per event. We have searched for possible ? polarization. The production ofK0's and ?'s in jets is examined as a function ofpT2 and rapidity and compared to that of all charged particles; the yields in two and three jets are also investigated. Results are presented from events with two baryons " observed.

Published
1985
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10. Jet production and fragmentation ine+e− annihilation at 12–43 GeV

Author

Althoff, M., Braunschweig, W., Kirschfink, F. J., Lübelsmeyer, K., Martyn, H. -U., Peise, G., Rimkus, J., Rosskamp, P., Sander, H. G., Schmitz, D., Siebke, H., Wallraff, W., Fischer, H. M., Hartmann, H., Hillen, W., Joksch, A., Knop, G., Köpke, L., Kolanoski, H., Kück, H., Mertens, V., Wedemeyer, R., Wermes, N., Wollstadt, M., Eisenberg, Y., Gather, K., Hultschig, H., Joos, P., Koch, W., Kötz, U., Kowalski, H., Ladage, A., Löhr, B., Lüke, D., Mattig, P., Notz, D., Nowak, R. J., Pyrlik, J., Quarrie, D. R., Rushton, M., Schütte, W., Trines, D., Wolf, G., Xiao, Ch., Fohrmann, R., Hilger, E., Kracht, T., Krasemann, H. L., Leu, P., Lohrmann, E., Pandoulas, D., Poelz, G., Pösnecker, K. U., Wiik, B. H., Beuselinck, R., Binnie, D. M., Campbell, A. J., Dornan, P. J., Foster, B., Garbutt, D. A., Jenkins, C., Jones, T. D., Jones, W. G., McCardle, J., Sedgbeer, J. K., Thomas, J., Abdullah, W. A. T. Wan, Bell, K. W., Bowler, M. G., Bull, P., Cashmore, R. J., Clarke, P. E. L., Devenish, R., Grossmann, P., Hawkes, C. M., Lloyd, S. L., Salmon, G. L., Wyatt, T. R., Youngman, C., Forden, G. E., Hart, J. C., Harvey, J., Hasell, D. K., Proudfoot, J., Saxon, D. H., Woodworth, P. L., Barreiro, F., Dittmar, M., Holder, M., Neumann, B., Duchovni, E., Karshon, U., Mikenberg, G., Mir, R., Revel, D., Ronat, E., Shapira, A., Yekutieli, G., Baranko, G., Barklow, T., Caldwell, A., Cherney, M., Izen, J. M., Mermikides, M., Rudolph, G., Strom, D., Venkataramania, H., Wicklund, E., Wu, Sau Lan, and Zobernig, G.

Abstract

We present the general properties of jets produced bye+e- annihilation. Their production and fragmentation characteristics have been studied with charged particles for c.m. energies between 12 and 43 GeV. In this energy rangee+e- annihilation into hadrons is dominated by pair production of the five quarksu, d, s, c andb. In addition, hard gluon bremsstrahlung effects which are invisible at low energies become prominent at the high energies. The observed multiplicity distributions deviate from a Poisson distribution. The multiplicity distributions for the overall event as well as for each event hemisphere satisfy KNO scaling to within ~20%. The distributions ofxp=2p/W are presented; scale breaking is observed at the level of 25%. The quantityxpdd/dxp is compared with multigluon emission calculations which predict a Gaussian distribution in terms of ln(1/x). The observed energy dependence of the maximum of the distributions is in qualitative agreement with the calculations. Particle production is analysed with respect to the jet axis and longitudinal and transverse momentum spectra are presented. The angular distribution of the jet axis strongly supports the idea of predominant spin 1/2 quark pair production. The particle distributions with respect to the event plane show clearly the growing importance of planar events with increasing c.m. energies. They also exclude the presence of heavy quark production,e+e-?Q " for quark masses up to 5Q<20.3 GeV (|eQ|=2/3) and 7Q<19 GeV (|eQ|=1/3). The comparison of 1/stotdd/dpT measured at 14, 22 and 34 GeV suggests that hard gluon bremsstrahlung contributes mainly to transverse momenta larger than 0.5 GeV/c. The rapidity distribution forW?22 GeV shows an enhancement away fromy=0 which corresponds to an increase in yield of 10–15% compared to the centre region (y=0). The enhancement probably results from heavy quark production and gluon bremsstrahlung. The particle flux around the jet axis shows with increasing c.m. energy a rapidly growing number of particles collimated around the jet axis, while at large angles to the jet axis almost noW dependence is observed. For fixed longitudinal momentump? approximate “fan invariance” is seen: The shape of the angular distribution around the jet axis is almost independent ofW. The collimation depends strongly onp?. For smallp?,p?<0.2 GeV/c, isotropy is observed. With increasingp? the particles tend to be emitted closer and closer to the jet axis.

Published
1984
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11. Production and muonic decay of heavy quarks ine+e− annihilation at 34.5 GeV

Author

Althoff, M., Braunschweig, W., Kirschfink, F. J., Lübelsmeyer, K., Martyn, H. -U., Peise, G., Rimkus, J., Rosskamp, P., Sander, H. G., Schmitz, D., Siebke, H., Wallraff, W., Fischer, H. M., Hartmann, H., Hillen, W., Jocksch, W., Knop, G., Köpke, L., Kolanoski, H., Kück, H., Wedemeyer, R., Wermes, N., Wollstadt, M., Eisenberg, Y., Gather, K., Hultschig, H., Joos, P., Koch, W., Kötz, U., Kowalski, H., Ladage, A., Löhr, B., Lüke, D., Mättig, P., Notz, D., Nowak, R. J., Pyrlik, J., Quarrie, D. R., Rushton, M., Schütte, W., Trines, D., Wolf, G., Xiao, Ch., Fohrmann, R., Hilger, E., Kracht, T., Krasemann, H. L., Leu, P., Lohrmann, E., Pandoulas, D., Poelz, G., Wiik, B. H., Beuselinck, R., Binnie, D. M., Campbell, A. L., Dornan, P. J., Foster, B., Garbutt, D. A., Jenkins, C., Jones, T. D., Jones, W. G., McCardle, J., Sedgbeer, J. K., Abdullah, W. A. T. Wan, Bell, K. W., Bowler, M. G., Bull, P., Cashmore, R. J., Clarke, P. E. L., Devenish, R., Grossmann, P., Hawkes, C. M., Lloyd, S. L., Salmon, G. L., Thomas, J., Wyatt, T. R., Youngman, C., Forden, G. E., Hart, J. C., Harvey, J., Hasell, D. K., Proudfoot, J., Saxon, D. H., Woodworth, P. L., Barreiro, F., Dittmar, M., Holder, M., Neumann, B., Duchovni, E., Karshon, U., Mikenberg, G., Mir, R., Revel, D., Ronat, D., Shapira, A., Yekutieli, G., Barklow, T., Caldwell, A., Cherney, M., Izen, J. M., Mermikides, M., Rudolph, G., Strom, D., Venkataramania, H., Wicklund, E., Wu, Sau Lan, and Zobernig, G.

Abstract

The production of prompt muons ine+e- annihilation has been studied at centre of mass energies near 34.5 GeV. The measured semi-muonic branching ratios ofb andc quarks areB(b»Xµv) =0.117±0.028±0.01 andB(c?Xµv)=0.082 ±0.012a-0.01+0.02. The fragmentation functions of heavy quarks are hard, b>=0.85a-0.12–0.07+0.10+0.02 and c> =0.77a-0.07–0.11+0.05+0.03. Limits have been set on flavour changing neutral current decays:B(b?Xµ+µ-) <0.02 andB(b?Xµ+µ- (95% confidence level).

Published
1984
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12. An improved measurement of electroweak couplings frome+e−→e+e− ande+e−→μ+μ−

Author

Althoff, M., Braunschweig, W., Kirschfink, F. J., Lübelsmeyer, K., Martyn, H. -U., Peise, G., Rimkus, J., Rosskamp, P., Sander, H. G., Schmitz, D., Siebke, H., Wallraff, W., Fischer, H. M., Hartmann, H., Hillen, W., Jocksch, A., Knop, G., Köpke, L., Kolanoski, H., Kück, H., Wedemeyer, R., Wermes, N., Wollstadt, M., Burkhardt, H., Eisenberg, Y., Gather, K., Hultschig, H., Joos, P., Koch, W., Kötz, U., Kowalski, H., Ladage, A., Lohr, B., Lüke, D., Mättig, P., Notz, D., Pyrlik, J., Quarrie, D. R., Rushton, M., Schütte, W., Trines, D., Wolf, G., Xiao, Ch., Fohrmann, R., Hilger, E., Kracht, T., Krasemann, H. L., Leu, P., Lohrmann, E., Pandoulas, D., Poelz, G., Wiik, B. H., Beuselinck, R., Binnie, D. M., Campbell, A. J., Dornan, P. J., Foster, B., Garbutt, D. A., Jenkins, C., Jones, T. D., Jones, W. G., McCardle, J., Sedgbeer, J. K., Wan Abdullah, W. A. T., Bell, K. W., Bowler, M. G., Brock, I. C., Cashmore, R. J., Clarke, P. E. L., Devenish, R., Grossmann, P., Llyod, S. L., Salmon, G. L., Thomas, J., Wyatt, T. R., Youngman, C., Hart, J. C., Harvey, J., Hasell, D. K., Proudfoot, J., Saxon, D. H., Woodworth, P. L., Barreiro, F., Dittmar, M., Holder, M., Neumann, B., Duchovni, E., Karshon, U., Mikenberg, G., Mir, R., Revel, D., Ronat, E., Shapira, A., Yekutieli, G., Barklow, T., Caldwell, A., Cherney, M., Izen, J. M., Mermikides, M., Rudolph, G., Strom, D., Venkataramania, H., Wicklund, E., Wu, Sau Lan, and Zobernig, G.

Abstract

We present an analysis of electroweak leptonic couplings from high statistics experiments on Bhabha scattering and μ pair production at an energy of 34.5 GeV. The forward-backward charge asymmetry of the μ pairs was measured to be −0.098±0.023±0.005. The data were found to agree well with the standard theory of electroweak interaction giving sin2θW=0.27±0.07. The leptonic weak couplings were determined to begv=0.000±0.170 andgA=−0.481±0.055. The data were also used to investigate a class of composite models for leptons.

Published
1984
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13. Production of charmed mesons in γγ interactions

Author

Braunschweig, W., Gerhards, R., Kirschfink, F. J., Martyn, H. -U., Bock, B., Fischer, H. M., Hartmann, H., Hartmann, J., Hilger, E., Jocksch, A., Wedemeyer, R., Foster, B., Martin, A. J., Bernardi, E., Chwastowski, J., Eskreys, A., Genser, K., Hultschig, H., Joos, P., Kowalski, H., Ladage, A., Löhl, B., Lüke, D., Notz, D., Pawlak, J. M., Pösnecker, K. -U., Ros, E., Trines, D., Walczak, R., Wolf, G., Kolanoski, H., Kracht, T., Krüger, J., Lohrmann, E., Poelz, G., Zeuner, W., Hassard, J., Shulman, J., Su, D., Tomalin, I. R., Barreiro, F., Leites, A., del Peso, J., Hart, J. C., Saxon, D. H., Brandt, S., Holder, M., Duchovni, E., Eisenberg, Y., Hochman, D., Karshon, U., Lyons, L., Montag, A., Revel, D., Ronat, E. E., Wainer, N., Muller, D., Ritz, S., Strom, D., Takashima, M., Wu, Sau Lan, and Zobernig, G.

Abstract

Production of charmed mesons in ??-interactions at PETRA energies has been observed in the TASSO detector. Cross sections for inclusiveD*± and " production have been measured. Neutral and charged meson pairs are estimated to be produced with comparable cross sections, and their sum seems to account for a sizeable fraction of stot(???hadrons) near the " threshold.

Published
1990
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14. A search for particles with magnetic charge produced ine+e− annihilations at 543-1543-1543-1GeV

Author

Braunschweig, W., Gerhards, R., Kirschfink, F. J., Martyn, H. U., Rosskamp, P., Bock, B., Eisenmann, J., Fischer, H. M., Hartmann, H., Hilger, E., Jocksch, A., Mertens, V., Wedemeyer, R., Foster, B., Martin, A. J., Sephton, A. J., Bernardi, E., Chwastowski, J., Eisenberg, Y., Eskreys, A., Gather, K., Hultschig, H., Genser, K., Joos, P., Kowalski, H., Ladage, A., Löhr, B., Lüke, D., Mättig, P., Montag, A., Notz, D., Pawlak, J. M., Ronat, E., Trines, D., Tymieniecka, T., Walczak, R., Wolf, G., Zeuner, W., Kolanoski, H., Kracht, T., Krüger, J., Lohrmann, E., Poelz, G., Pösnecker, K. U., Binnie, D. M., Hassard, J., Sedgbeer, J. K., Shulman, J., Su, D., Watson, A. T., Barreiro, F., Leites, A., del Peso, J., Ros, E., Balkwill, C., Bowler, M. G., Burrows, P. N., Cashmore, R. J., Dauncey, P., Heath, G. P., Mellor, D. J., Ratoff, P., Tomalin, I., Yelton, J. M., Lloyd, S. L., Forden, G. E., Hart, J. C., Saxon, D. H., Brandt, S., Holder, M., Labarga, L., Karshon, U., Mikenberg, G., Revel, D., Shapira, A., Wainer, N., Yekutieli, G., Baranko, G., Caldwell, A., Cherney, M., Izen, J. M., Muller, D., Ritz, S., Strom, S., Takashima, M., Wicklund, E., Wu, Sau Lan, and Zobernig, G.

Abstract

By seeking to identify magnetically charged particles by their trajectories in a magnetic field, we set limits on the production of monopoles and dyons, via the processe+e-??*?M ", of masses up to 17 GeV and of magnetic charges between 10 e and 70 e

Published
1988
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15. Inclusiveπ0 production bye+e− annihilation at 34.6 GeV center of mass energy

Author

Braunschweig, W., Gerhards, R., Kirschfink, F. J., Martyn, H. -U., Rosskamp, P., Vogel, E., Wallraff, W., Bock, B., Eisenmann, J., Fischer, H. M., Hartmann, H., Hilger, E., Jocksch, A., Kolanoski, H., Kück, H., Mertens, V., Wedemeyer, R., Foster, B., Martin, A. J., Bernardi, E., Eisenberg, Y., Eskreys, A., Gather, K., Hultschig, H., Joos, P., Klima, B., Kowalski, H., Ladage, A., Löhr, B., Lüke, D., Mättig, P., Montag, A., Notz, D., Shapira, A., Trines, D., Tymieniecka, T., Tysarczyk, G., Walczak, R., Wolf, G., Yekutieli, G., Zeuner, W., Kracht, T., Krasemann, H. L., Krueger, J., Lohrmann, E., Poelz, G., Poesnecker, K. -U., Binnie, D. M., Dornan, P. J., Garbutt, D. A., Jenkins, C., Jones, W. G., Sedgbeer, J. K., Shulman, J., Su, D., Watson, A. P., Barreiro, F., Ros, E., Balkwill, C., Bowler, M. G., Burrows, P. N., Cashmore, R. J., Dauncey, P., Devenish, R., Heath, G., Mellor, D. J., Ratoff, P., Tomalin, I., Yelton, J. M., Lloyd, S. L., Forden, G. E., Hart, J. C., Hasell, D. K., Saxon, D. H., Brandt, S., Holder, M., Labarga, L., Neumann, B., Karshon, U., Mikenberg, G., Mir, R., Revel, D., Ronat, E., Wainer, N., Baranko, G., Caldwell, A., Cherney, M., Izen, J. M., Ritz, S., Strom, D., Takashima, M., Wicklund, E., Wu, Sau Lan, and Zobernig, G.

Abstract

The cross section for the processe+e-?p0+ anything has been measured at an average center of mass energy of 34.6 GeV for p0 energies between 0.7 and 17 GeV. The angular distribution for p0 energies larger than 2 GeV is of the formds/dO~1+Acos2?, withA=1.2±0.5. The ratio of p0 to p± production in the measured energy range is 2s(p0)/(s(p+)+s(p-))=1.13±0.18

Published
1986
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16. A measurement of theD0 lifetime

Author

Althoff, M., Braunschweig, W., Gerhards, R., Kirschfink, F. J., Martyn, H. -U., Rosskamp, P., Wallraff, W., Bock, B., Eisenmann, J., Fischer, H. M., Hartmann, H., Jocksch, A., Kolanoski, H., Mertens, V., Wedemeyer, R., Foster, B., Bernardi, E., Eisenberg, Y., Eskreys, A., Gather, K., Hultschig, H., Joos, P., Klima, B., Kowalski, H., Ladage, A., Löhr, B., Lüke, D., Mättig, P., Notz, D., Revel, D., Ronat, E., Schütte, W., Trines, D., Tymieniecka, T., Walczak, R., Wolf, G., Zeuner, W., Hilger, E., Kracht, T., Krasemann, H. L., Krüger, J., Lohrmann, E., Poelz, G., Pösnecker, K. -U., Binnie, D. M., Dornan, P. J., Garbutt, D. A., Jenkins, C., Jones, W. G., Sedgbeer, J. K., Su, D., Thomas, J., Wan Abdullah, W. A. T., Barreiro, F., Ros, E., Bowler, M. G., Bull, P., Cashmore, R. J., Dauncey, P., Devenish, R., Heath, G., Mellor, D. J., Ratoff, P., Yelton, J. M., Lloyd, S. L., Forden, G. E., Hart, J. C., Hasell, D. K., Saxon, D. H., Brandt, S., Holder, M., Labarga, L., Neumann, B., Karshon, U., Mikenberg, G., Mir, R., Montag, A., Yekutieli, G., Shapira, A., Baranko, G., Caldwell, A., Cherney, M., DeMille, D., Izen, J. M., Messersmith, J., Ritz, S., Strom, D., Takashima, M., Wicklund, E., Wu, Sau Lan, and Zobernig, G.

Abstract

We have determined theD0 lifetime from reconstructed vertices ofD0 mesons produced ine+e- annihilations at an average center of mass energy of 42.2 GeV. From fifteen events theD0 lifetime was determined to be (4.3-1.4+2.0±0.8)×10-13s.

Published
1986
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17. Vector meson production in the final stateK+K−π+π− of photon-photon collisions

Author

Althoff, M., Braunschweig, W., Gerhards, R., Kirschfink, J.F., Martyn, H. -U., Rosskamp, P., Wallraff, W., Bock, B., Eisenmann, J., Fischer, H.M., Hartmann, H., Jocksch, A., Kolanoski, H., Kück, H., Mertens, V., Wedemeyer, R., Foster, B., Bernardi, E., Eisenberg, Y., Eskreys, A., Gather, K., Hultschig, H., Joos, P., Klima, B., Kowalski, H., Ladage, A., Löhr, B., Lüke, D., Mättig, P., Notz, D., Revel, D., Ronat, E., Trines, D., Tymieniecka, T., Walczak, R., Wolf, G., Zeuner, W., Hilger, E., Kracht, T., Krasemann, H. L., Krüger, J., Lohrmann, E., Poelz, G., Pösnecker, K. -U., Binnie, D. M., Dornan, P., Garbutt, D. A., Jenkins, C., Jones, W. G., Sedgbeer, J. K., Su, D., Thomas, J., Wan Abdullah, W. A. T., Barreiro, F., Ros, E., Bowler, M. G., Bull, P., Cashmore, R. J., Dauncey, P., Devenish, R., Heath, G., Mellor, D. J., Ratoff, P., Lloyd, S. L., Bell, K., Forden, G. E., Hart, J. C., Hasell, D. K., Saxon, D. H., Brandt, S., Holder, M., Labarga, L., Neumann, B., Karshon, U., Mikenberg, G., Montag, A., Mir, R., Duchovni, E., Shapira, A., Yekutieli, G., Baranko, G., Caldwell, A., Cherney, M., Izen, J. M., Ritz, S., Strom, D., Takashima, M., Wicklund, E., Lan Wu, Sau, and Zobernig, G.

Abstract

Vector meson production is studied in the reaction ???K+K-p+p-. A clear F(1020) signal is seen in theK+K- mass distribution and aK*0 (890) signal is visible in theK±p± one. Both do not seem to be strongly correlated with quasi two body final states. Cross sections for the processes ???K+K-p+p-, ???Fp+p-, ???K+0K±p± and upper limits for the production of Fp, FF andK*0 " are given as function of the invariant ?? mass.

Published
1986
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18. Measurement of the radiative width of theA2(1320) in two-photon interactions

Author

Althoff, M., Braunschweig, W., Gerhards, R., Kirschfink, F. J., Martyn, H. -U., Rosskamp, P., Wallraff, W., Bock, B., Eisenmann, J., Fischer, H. M., Hartmann, H., Jocksch, A., Kolanoski, H., Kück, H., Mertens, V., Wedemeyer, R., Foster, B., Bernardi, E., Eisenberg, Y., Eskreys, A., Gather, K., Hultschig, H., Joos, P., Klima, B., Kowalski, H., Ladage, A., Löhr, B., Lüke, D., Mättig, P., Notz, D., Revel, D., Ronat, E., Trines, D., Tymieniecka, T., Walczak, R., Wolf, G., Zeuner, W., Hilger, E., Kracht, T., Krasemann, H. L., Krüger, J., Lohrmann, E., Poelz, G., Pösnecker, K. U., Binnie, D. M., Dornan, P. J., Garbutt, D. A., Jenkins, C., Jones, W. G., Sedgbeer, J. K., Su, D., Thomas, J., Wan Abdullah, W. A. T., Barreiro, F., Ros, E., Bowler, M. G., Bull, P., Cashmore, R. J., Dauncey, P., Devenish, R., Heath, G., Mellor, D., Ratoff, P., Lloyd, S. L., Forden, G. E., Hart, J. C., Hasell, D. K., Saxon, D. H., Brandt, S., Holder, M., Labarga, L., Neumann, B., Karshon, U., Mikenberg, G., Mir, R., Montag, A., Shapira, A., Yekutieli, G., Baranko, G., Caldwell, A., Cherney, M., Izen, J. M., Ritz, S., Strom, D., Takashima, M., Wicklund, E., Wu, Sau Lan, and Zonering, G.

Abstract

The reactione+e-?e+e- A2 (1320) has been observed by detecting the decayA2?p+,p-p0. The two-photon width of theA2 has been measured to be ?(A2???)=(0.09±0.27 (stat)±0.16 (syst)) keV. The cross section s(???p+,p-p0 has been determined outside theA2 resonance region.

Published
1986
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19. Measurement of the photon structure functionF2ψ atQ2 from 7 to 70 (GeV/c)2

Author

Althoff, M., Braunschweig, W., Gerhards, R., Kirschfink, F. J., Martyn, H. U., Rosskamp, P., Wallraff, W., Bock, B., Eisenmann, J., Fischer, H. M., Hartmann, H., Hillen, W., Jocksch, A., Kolanoski, H., Kück, H., Mertens, V., Wedemeyer, R., Foster, B., Bernardi, E., Eisenberg, Y., Eskreys, A., Gather, K., Hultschig, H., Joos, P., Klima, B., Kowalski, H., Ladage, A., Löhr, B., Lueke, D., Mättig, P., Notz, D., Revel, D., Ronat, E., Trines, D., Tymieniecka, T., Walczak, R., Wolf, G., Zeuner, W., Hilger, E., Kracht, T., Krasemann, H. L., Krüger, J., Lohrmann, E., Poelz, G., Pösnecker, K. U., Binnie, D. M., Dornan, P. J., Garbutt, D. A., Jenkins, C., Jones, W. G., Sedgbeer, J. K., Su, D., Thomas, J., Abdullah, W. A. T. Wan, Barreiro, F., Ros, E., Bowler, M. G., Bull, P., Cashmore, R. J., Dauncey, P., Devenish, R., Heath, G., Mellor, D. J., Lloyd, S. L., Forden, G. E., Hart, J. C., Hasell, D. K., Saxon, D. H., Brandt, S., Dittmar, M., Holder, M., Labarga, L., Neumann, B., Karshon, U., Mikenberg, G., Montag, A., Mir, R., Shapira, A., Yekutieli, G., Baranko, G., Caldwell, A., Cherney, M., Izen, J. M., Ritz, S., Strom, D., Takashima, M., Venkataramania, H., Wicklund, E., Wu, Sau Lan, and Zobernig, G.

Abstract

We have measured the processe+e−→e+e−+hadrons, where one of the scattered electrons was detected at large angles, withQ2 ranging from 7 to 70 (VeV/c)2. The photon structure functionF2γ(x, Q2) was determined at an averageQ2 of 23 (GeV/c)2. The measurements were compared to theoretical predictions of the Quark Parton Model and Quantum Chromodynamics. In both models a hadronic part was added. Within the errors the data are in agreement with the QPM using quark masses of 300 MeV/c2 for the light quarks. The data also agree with a QCD calculation including higher order corrections. A fit yielded a " value of 140−65+190 MeV, where the errors include statistical and systematic uncertainties.

Published
1986
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20. Study ofη production in two-photon collisions

Author

Braunschweig, W., Gerhards, R., Kirschfink, F. J., Martyn, H. -U., Bock, B., Fischer, H. M., Hartmann, H., Hartmann, J., Hilger, E., Jocksch, A., Mertens, V., Wedemeyer, R., Foster, B., Martin, A. J., Sephton, A. J., Bernardi, E., Chwastowski, J., Eskreys, A., Gather, K., Genser, K., Hultschig, H., Joos, P., Kowalski, H., Ladage, A., Löhr, B., Lüke, D., Märtig, P., Notz, D., Pawlak, J. M., Posnecker, K. -U., Ros, E., Trines, D., Walczak, R., Wolf, G., Kolanoski, H., Kracht, T., Krüger, J., Lohrmann, E., Poelz, G., Zeuner, W., Hassard, J., Shulman, J., Su, D., Barreiro, F., Leites, A., del Peso, J., Balkwill, C., Bowler, M. G., Burrows, P. N., Heath, G. P., Ratoff, P., Silvester, I., Tomalin, I., Veitch, E., Forden, G. E., Hart, J. C., Saxon, D. H., Brandt, S., Holder, M., Labarga, L., Duchovni, E., Eisenberg, Y., Hochman, D., Karshon, U., Lyons, L., Mikenberg, G., Montag, A., Revel, D., Ronat, E., Shapira, A., Wainer, N., Yekutieli, G., Caldwell, A., Muller, D., Ritz, S., Strom, D., Takashima, M., Wicklund, E., Wu, Sau Lan, and Zobernig, G.

Abstract

Production of theηc meson ine+e− quasireal two photon collisions has been looked for in three channels. The data were obtained from an integrated luminosity of 189 pb−1. Anηc signal is observed in two decay modes (Ks0K±π∓,π+π-π+π-) with a combined statistical significance of 3.5 standard deviations. Using the knownηc branching ratios to these channels and toK+K-π+π- the combined partialηc width to γγ isΓγγ(ηc). The first error is statistical, and the second one includes the systematic and branching ratio errors. Calculated as an upper limit we obtainΓγγ(ηc) (95% C.L., including the systematic error).

Published
1989
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21. A measurement of muon pair production ine+e− annihilation at centre of mass energies 35.0≤ <img src="/fulltext-image.asp?format=htmlnonpaginated&src=M4221N1LN3801R3W_html\10052_2005_Article_BF01555879_TeX2GIFIE1.gi

Author

Braunschweig, W., Gerhards, R., Kirschfink, F. J., Martyn, H. -U., Bock, B., Fischer, H. M., Hartmann, H., Hartmann, J., Hilger, E., Jocksch, A., Wedemeyer, R., Foster, B., Martin, A. J., Sephton, A. J., Bernardi, E., Chwastowski, J., Eskreys, A., Gather, K., Genser, K., Hultschig, H., Joos, P., Kowalski, H., Ladage, A., Löhr, B., Lüke, D., Mättig, P., Notz, D., Pawlak, J. M., Pösnecker, K. -U., Ros, E., Trines, D., Walczak, R., Wolf, G., Kolanoski, H., Kracht, T., Krüger, J., Lohrmann, E., Poelz, G., Zeuner, W., Hassard, J., Shulman, J., Su, D., Barreiro, F., Hervas, L., Leites, A., del Peso, J., Traseira, M., Balkwill, C., Bowler, M. G., Burrows, P. N., Cashmore, R. J., Hawkes, C. M., Heath, G. P., Ratoff, P. N., Silvester, I. M., Tomalin, I. R., Veitch, M. E., Forden, G. E., Hart, J. C., Saxon, D. H., Brandt, S., Holder, M., Labarga, L., Duchovni, E., Eisenberg, Y., Karshon, U., Mikenberg, G., Montag, A., Revel, D., Ronat, E., Wainer, A. N., Yekutieli, G., Muller, D., Ritz, S., Strom, D., Takashima, M., Wu, Sau Lan, and Zobernig, G.

Abstract

The reactione+e−→µ+µ− has been studied at centre of mass energies between 35.0 and 46.8 GeV using the TASSO detector at PETRA. We present measurements of the forward-backward charge asymmetry (Aμμ) and cross section σμμ for this reaction at three energies. At 35.0 GeV we obtain a cross section relative to the QED prediction ofRμμ=σμμ/σo=0.932±0.018±0.044 andAμμ=(−10.6−2.3+2.2±0.5)%. At 38.3 GeV we findRμμ=0.951±0.072−0.057+0.063 andAμμ=(+1.7−8.6+8.5±0.5)%. At 43.6 GeV we measureRμμ=0.921±0.037±0.055 andAμμ=(−17.6−4.3+4.4±0.5)%. Our results are in good agreement with the predictions of the standard model. Including previous TASSO data we present improved determinations of muonic electroweak parameters. We also report on lower limits of possible contributions from contact interactions.

Published
1988
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22. A study of Bhabha scattering at PETRA energies

Author

Braunschweig, W., Gerhards, R., Kirschfink, F. J., Martyn, H. -U., Rosskamp, P., Bock, B., Fischer, H. M., Hartmann, H., Hartmann, J., Hilger, E., Jocksch, A., Mertens, V., Wedemeyer, R., Foster, B., Martin, A. J., Sephton, A. J., Barreiro, F., Bernardi, E., Chwastowski, J., Eisenberg, Y., Eskreys, A., Gather, K., Genser, K., Hultschig, H., Joos, P., Kowalski, H., Ladage, A., Löhr, B., Lüke, D., Mättig, P., Montag, A., Notz, D., Pawlak, J., Ronat, E., Ros, E., Trines, D., Tymieniecka, T., Walczak, R., Wolf, G., Zeuner, W., Kolanoski, H., Kracht, T., Krüger, J., Lohrmann, E., Poelz, G., Pösnecker, K. -U., Binnie, D. M., Sedgbeer, J. K., Shulman, J., Su, D., Watson, A. T., Cerezo, J. P., Garcia, M. A., Leites, A., del Peso, J., de Troconiz, J. F., Balkwill, C., Bowler, M. G., Burrows, P. N., Cashmore, R. J., Dauncey, P., Heath, G. P., Mellor, D. J., Ratoff, P., Tomalin, I., Yelton, J. M., Lloyd, S. L., Forden, G. E., Hart, J. C., Saxon, D. H., Brandt, S., Holder, M., Labarga, L., Karshon, U., Mikenberg, G., Revel, D., Shapira, A., Wainer, N., Yekutieli, G., Baranko, G., Caldwell, A., Izen, J. M., Muller, D., Ritz, S., Strom, D., Takashima, M., Wicklund, E., Wu, Sau Lan, and Zobernig, G.

Abstract

We report on high statistics Bhabha scattering data taken with the TASSO experiment at PETRA at center of mass energies from 12 GeV to 46.8 GeV. We present an analysis in terms of electroweak parameters of the standard model, give limits on QED cut-off parameters and look for possible signs of compositeness.

Published
1988
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23. Measurement of the average lifetime ofB hadrons

Author

Braunschweig, W., Gerhards, R., Kirschfink, F. J., Martyn, H. -U., Bock, B., Fischer, H. M., Hartmann, H., Hartmann, J., Hilger, E., Jocksch, A., Wedemeyer, R., Foster, B., Martin, A. J., Sephton, A. J., Barreiro, F., Bernardi, E., Chwastowski, J., Eskreys, A., Gather, K., Genser, K., Hultschig, H., Joos, P., Kowalski, H., Ladage, A., Löhr, B., Lüke, D., Mättig, P., Notz, D., Pawlak, J. M., Pösnecker, K. -U., Ros, E., Trines, D., Walczak, R., Wolf, G., Kolanoski, H., Kracht, T., Krüger, J., Lohrmann, E., Poelz, G., Zeuner, W., Belk, A., Binnie, D. M., Hassard, J., Shulman, J., Su, D., Leites, A., del Peso, J., Balkwill, C., Bowler, M. G., Burrows, P. N., Cashmore, R. J., Heath, G. P., Ratoff, P. N., Silvester, I. M., Tomalin, I. R., Veitch, M. E., Forden, G. E., Hart, J. C., Saxon, D. H., Brandt, S., Holder, M., Labarga, L., Eisenberg, Y., Karshon, U., Mikenberg, G., Montag, A., Revel, D., Ronat, E., Shapira, A., Wainer, N., Yekutieli, G., Caldwell, A., Muller, D., Ritz, S., Strom, D., Takashima, M., Wu, Sau Lan, and Zobernig, G.

Abstract

The average lifetime ofB hadrons has been measured by the TASSO collaboration using 110 pb-1 of data collected in 1986 at a center of mass energy of 35 GeV. Measurements by three different methods are presented and a method ofB-enrichment is discussed. The result of the impact parameter method is tB=1.36±0.13±0.28 ps, that of the vertex method is tB=1.30±0.10±0.28 ps and that of the dipole method is tB=1.47±0.14±0.30 ps. These are combined to give the result tB=1.35±0.10±0.24 ps.

Published
1989
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24. A study of energy-energy correlations between 12 and 46.8 GeV c.m. energies

Author

Braunschweig, W., Gerhards, R., Kirschfink, F. J., Martyn, H. -U., Rosskamp, P., Bock, B., Eisenmann, J., Fischer, H. M., Hartmann, H., Hilger, E., Jocksch, A., Mertens, V., Wedemeyer, R., Foster, B., Martin, A. J., Sephton, A. J., Barreiro, F., Bernardi, E., Chwastowski, J., Eisenberg, Y., Eskreys, A., Gather, K., Hultschig, H., Genser, K., Joos, P., Kowalski, H., Ladage, A., Löhr, B., Lüke, D., Mättig, P., Montag, A., Notz, D., Pawlak, J., Ronat, E., Trines, D., Tymieniecka, T., Walczak, R., Wolf, G., Zeuner, W., Kolanoski, H., Kracht, T., Krüger, J., Lohrmann, E., Poelz, G., Pösnecker, K. -U., Binnie, D. M., Sedgbeer, J. K., Shulman, J., Su, D., Watson, A. T., Leites, A., del Peso, J., Ros, E., Balkwill, C., Bowler, M. G., Burrows, P. N., Cashmore, R. J., Dauncey, P., Heath, G. P., Mellor, D. J., Ratoff, P., Tomalin, I., Yelton, J. M., Lloyd, S. L., Forden, G. E., Hart, J. C., Saxon, D. H., Brandt, S., Holder, M., Labarga, L., Karshon, U., Mikenberg, G., Revel, D., Shapira, A., Wainer, N., Yekutieli, G., Baranko, G., Caldwell, A., Cherney, M., Izen, J. M., Muller, D., Ritz, S., Strom, D., Takashima, M., Wicklund, E., Wu, Sau Lan, and Zobernig, G.

Abstract

We present data on energy-energy correlations (EEC) and their related asymmetry (AEEC) ine+e- annihilation in the centre of mass energy range 12s2 QCD plus a fragmentation term proportional to ". BareO(a)s2 QCD reproduces our data for the large angle region of the AEEC. Nonperturbative effects for the latter are estimated with the help of fragmentation models. From various analyses using different approximations, we find that values for " in the range 0.1–0.3 GeV give a good description of the data. We also compare analytical calculations in QCD for the EEC in the back-to-back region to our data. The theoretical predictions describe well both the angular and energy dependence of the data in the back-to-back region.

Published
1987
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25. Measurement of the two-photon reactionγγ →π+π−π+π− at large values ofQ2

Author

Braunschweig, W., Gerhards, R., Kirschfink, F. J., Martyn, H. -U., Bock, B., Fischer, H. M., Hartmann, H., Hartmann, J., Hilger, E., Jocksch, A., Wedemeyer, R., Foster, B., Martin, A. J., Sephton, A. J., Barreiro, F., Bernardi, E., Chwastowski, J., Eskreys, A., Gather, K., Genser, K., Hultschig, H., Joos, P., Kowalski, H., Ladage, A., Löhr, B., Lüke, D., Mättig, P., Notz, D., Pawlak, J. M., Pösnecker, K. -U., Ros, E., Trines, D., Walczak, R., Wolf, G., Kolanoski, H., Kracht, T., Krüger, J., Lohrmann, E., Poelz, G., Zeuner, W., Binnie, D. M., Hassard, J., Shulman, J., Su, D., Leites, A., del Peso, J., Balkwill, C., Bowler, M. G., Burrows, P. N., Heath, G. P., Ratoff, P. N., Silvester, I. M., Tomalin, I. R., Veitch, M. E., Forden, G. E., Hart, J. C., Saxon, D. H., Brandt, S., Holder, M., Labarga, L., Eisenberg, Y., Karshon, U., Mikenberg, G., Montag, A., Revel, D., Ronat, E., Shapira, A., Wainer, N., Yekutieli, G., Caldwell, A., Muller, D., Ritz, S., Strom, D., Takashima, M., Wicklund, E., Wu, Sau Lan, and Zobernig, G.

Abstract

The process γγ→π+π−π+π− has been investigated in reactions of the typee+e−→e+e−π+π−π+π− in the single tag mode. The range of the four momentum squared of one of the virtual photons was 0.28 GeV2/c2≦Q2≦3.6 GeV2/c2, the average being 〈Q2〉=0.92 GeV2/c2; the other photon was quasi real. The reaction is mainly described by the channels γγ→ρ0ρ0 and γγ→4π (phase space), occuring with about equal probability. TheQ2-dependence of the cross section is in agreement with the ρ form factor.

Published
1988
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26. Jet fragmentation and QCD models ine+e− annihilation at c.m. energies between 12.0 and 41.5 GeV

Author

Braunschweig, W., Gerhards, R., Kirschfink, F. J., Martyn, H. -U., Bock, B., Fischer, H. M., Hartmann, H., Hartmann, J., Hilger, E., Jocksch, A., Wedemeyer, R., Foster, B., Martin, A. J., Sephton, A. J., Bernardi, E., Chwastowski, J., Eskreys, A., Gather, K., Genser, K., Hultschig, H., Joos, P., Kowalski, H., Ladage, A., Löhr, B., Lüke, D., Mättig, P., Notz, D., Pawlak, J. M., Pösnecker, K. -U., Ros, E., Trines, D., Walczak, R., Wolf, G., Kolanoski, H., Kracht, T., Krüger, J., Lohrmann, E., Poelz, G., Zeuner, W., Hassard, J., Shulman, J., Su, D., Barreiro, F., Leites, A., del Peso, J., Balkwill, C., Bowler, M. G., Burrows, P. N., Cashmore, R. J., Heath, G. P., Ratoff, P. N., Silvester, I. M., Tomalin, I. R., Veitch, M. E., Forden, G. E., Hart, J. C., Saxon, D. H., Brandt, S., Holder, M., Labarga, L., Eisenberg, Y., Karshon, U., Mikenberg, G., Montag, A., Revel, D., Ronat, E., Shapira, A., Wainer, N., Yekutieli, G., Muller, D., Ritz, S., Strom, D., Takashima, M., Wu, Sau Lan, and Zobernig, G.

Abstract

The large amount of data accumulated by the TASSO detector at 35 GeV c.m. energy has been compared with the predictions of the latest generation of perturbative QCD+fragmentation models. By adjustment of the arbitrary parameters of these models, a very good description of the global properties of hadronic events was obtained. No one model gave the best description of all features of the data, each model being better than the others for some observables and worse in other quantities. We interpret these results in terms of the underlying QCD and hadronisation schemes. The trends of the data across the energy range 12.0?W?41.5 GeV are generally well reproduced by the models with the parameters optimised at 35 GeV.

Published
1988
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27. Evidence for direct photons from quarks in electron-positron annihilation

Author

Braunschweig, W., Gerhards, R., Kirschfink, F. J., Martyn, H. -U., Bock, B., Fischer, H. M., Hartmann, H., Hartmann, J., Hilger, E., Jocksch, A., Wedemeyer, R., Foster, B., Martin, A. J., Sephton, A. J., Barreiro, F., Bernardi, E., Chwastowski, J., Eskreys, A., Gather, K., Genser, K., Hultschig, H., Joos, P., Kowalski, H., Ladage, A., Löhr, B., Lüke, D., Mättig, P., Notz, D., Pawlak, J. M., Pösnecker, K. -U., Ros, E., Trines, D., Tymieniecka, T., Walczak, R., Wolf, G., Kolanoski, H., Gerhardt, W., Kracht, T., Krüger, J., Lohrmann, E., Poelz, G., Rehders, P., Tysarczyk, G., Zeuner, W., Hassard, J., Shulman, J., Su, D., Leites, A., del Peso, J., Balkwill, C., Bowler, M. G., Burrows, P. N., Heath, G. P., Ratoff, P., Silvester, I., Tomalin, I. R., Veitch, M. E., Forden, G. E., Hart, J. C., Saxon, D. H., Brandt, S., Holder, M., Labarga, L., Eisenberg, Y., Karshon, U., Mikenberg, G., Montag, A., Revel, D., Ronat, E., Shapira, A., Wainer, N., Yekutieli, G., Muller, D., Ritz, S., Strom, D., Takashima, M., Wu, Sau Lan, and Zobernig, G.

Abstract

Hadronic events frome+e--annihilations with a high energy isolated photon have been investigated at C.M. energies between 14 GeV and 44 GeV. A forward-backward asymmetryA? of the positively charged jet with respect to the incident positron direction has been found:A??=-0.32±0.07, providing evidence for photon bremsstrahlung from quarks. The forward-backward asymmetry of all hadronic events at C.M. energies between 30 GeV and 36 GeV has been measured. The value, corrected for the limited polar angle acceptance of the detector, is:A=+0.021±0.005.

Published
1988
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28. Comparison of inclusive fractional momentum distributions of quark and gluon jets produced ine+e− annihilation

Author

Braunschweig, W., Gerhards, R., Kirschfink, F. J., Martyn, H. -U., Bock, B., Fischer, H. M., Hartmann, H., Hartmann, J., Hilger, E., Jocksch, A., Wedemeyer, R., Foster, B., Martin, A. J., Bernardi, E., Chwastowski, J., Eskreys, A., Gather, K., Genser, K., Hulschig, H., Joos, P., Kowalski, H., Ladage, A., Löhr, B., Lüke, D., Mättig, P., Notz, D., Pawlak, J. M., Pösnecker, K. -U., Ros, E., Trines, D., Walczak, R., Wolf, G., Kolanoski, H., Kracht, T., Krüger, J., Lohrmann, E., Poelz, G., Zeuner, W., Hassard, J., Shulman, J., Su, D., Tomalin, I. R., Barreiro, F., Leites, A., del Peso, J., Bowler, M. G., Burrows, P. N., Cashmore, R. J., Heath, G. P., Veitch, M. E., Hart, J. C., Saxon, D. H., Brandt, S., Holder, M., Eisenberg, Y., Karshon, U., Mikenberg, G., Montag, A., Revel, D., Ronat, E., Shapira, A., Wainer, N., Yekutieli, G., Muller, D., Ritz, S., Strom, D., Takashima, M., Wu, Sau Lan, and Zobernig, G.

Abstract

Inclusive charged particle production ine+e- annihilation into hadrons is studied in terms of the particle fractional momentumxp. Thexp distribution for gluon jets is extracted by comparing two data samples measured in the TASSO detector: nearly symmetric three jet events at centre-of-mass energyW~35 GeV and two jet events atW~22 GeV, yielding quark and gluon jets of similar energies (~11.5 GeV). No significant difference is observed between quark and gluon jets. Monte Carlo models based on parton showers describe the trend and energy variation of the data better than a model with second order matrix element in as.

Published
1989
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29. Experimental study of jet masses ine+e− annihilation at c.m. energies between 12 and 43.5 GeV

Author

Braunschweig, W., Gerhards, R., Kirschfink, F. J., Martyn, H. -U., Fischer, H. M., Hartmann, H., Hartmann, J., Hilger, E., Jocksch, A., Wedemeyer, R., Foster, B., Martin, A. J., Barreiro, F., Bernardi, E., Chwastowski, J., Genser, K., Kowalski, H., Löhr, B., Lüke, D., Notz, D., Pawlak, J. M., Pösnecker, K. -U., Ros, E., Walczak, R., Wolf, G., Kolanoski, H., Kracht, T., Krüger, J., Lohrmann, E., Poelz, G., Zeuner, W., Hassard, A., Shulman, J., Su, D., Tomalin, I., Leites, A., del Peso, J., Hervas, L., Traseira, M., Bowler, M. G., Burrows, P. N., Cashmore, R. J., Heath, G. P., Veitch, M. E., Hart, J. C., Saxon, D. H., Brandt, S., Holder, M., Labarga, L., Eisenberg, Y., Karshon, U., Mikenberg, G., Montag, A., Revel, D., Ronat, E., Wainer, A. N., Yekutieli, G., Muller, D., Ritz, S., Takashima, M., Wu, Sau Lan, Zobernig, G., and Caldwell, A.

Abstract

Data on jet masses, resulting from the decomposition ofe+e- hadronic final states into two hemispheres, are presented at centre of mass energies between 12 and 43.5 GeV. Comparisons are made with bareO(as2) QCD predictions as well as with QCD based fragmentation models. Values for as and " are determined, both with and without hadronization effects included. Upper and lower limits for " independent of fragmentation models have been determined to be 0.480±0.025 GeV and 0.047±0.007 GeV respectively.

Published
1989
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30. Strange baryon production ine+e− annihilation

Author

Braunschweig, W., Gerhards, R., Kirschfink, F., Martyn, H., Bock, B., Fischer, H., Hartmann, H., Hartmann, J., Hilger, E., Jocksch, A., Wedemeyer, R., Foster, B., Martin, A., Sephton, A., Bernardi, E., Chwastowski, J., Eskreys, A., Gather, K., Genser, K., Hultschig, H., Joos, P., Kowalski, H., Ladage, A., Löhr, B., Lüke, D., Mattig, P., Notz, D., Pawlak, J., Posnecker, K., Ros, E., Schütte, W., Trines, D., Walczak, R., Wolf, G., Kolanoski, H., Kracht, T., Krüger, J., Lohrmann, E., Poelz, G., Zeuner, W., Binnie, D., Hassard, J., Shulman, J., Su, D., Barreiro, F., Leites, A., Hervas, L., del Peso, J., Traseira, M., Balkwill, C., Bowler, M., Burrows, P., Cashmore, R., Heath, G., Ratoff, P., Silvester, I., Tomalin, I., Veitch, M., Yelton, J., Lloyd, S., Forden, G., Hart, J., Saxon, D., Brandt, S., Holder, M., Labarga, L., Eisenberg, Y., Karshon, U., Mikenberg, G., Montag, A., Revel, D., Ronat, E., Shapira, A., Wainer, N., Yekutieli, G., Muller, D., Ritz, S., Strom, D., Takashima, M., Wu, Sau, and Zobernig, G.

Abstract

Abstract: The production of strange baryons ine + e – annihilation has been studied at centre of mass energies of 34.8 GeV and 42.1 GeV, using the TASSO detector at DESY. Inclusive cross-sections have been obtained for$$\begin{gathered} \hfill \\ 0.218_{ - 0.011}^{ + 0.011} \pm 0.021 \hfill \\ \end{gathered} $$ and $$0.256_{ - 0.029}^{ + 0.030} \pm 0.025$$ at $$\sqrt s = 34.8$$ and 42.1 GeV respectively. The $$0.014_{ - 0.003}^{ + 0.003} \pm 0.004$$ at $$\sqrt s = 34.8 GeV$$ . An investigation has been made of the extent to whichLambda0 are produced in pairs. TheLambda0 cross-section has been studied as a function of event sphericity.

Published
1989
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31. Charged multiplicity distributions and correlations ine+e− annihilation at PETRA energies

Author

Braunschweig, W., Gerhards, R., Kirschfink, F., Martyn, H., Fischer, H., Hartmann, H., Hartmann, J., Hilger, E., Jocksch, A., Wedemeyer, R., Foster, B., Martin, A., Bernardi, E., Chwastowski, J., Eskreys, A., Gather, K., Genser, K., Hultschig, H., Joos, P., Kowalski, H., Ladage, A., Löhr, B., Lüke, D., Mättig, P., Notz, D., Pawlak, J., Pösnecker, K., Ros, E., Trines, D., Walczak, R., Wolf, G., Kolanoski, H., Kracht, T., Krüger, J., Lohrmann, E., Poelz, G., Zeuner, W., Hassard, J., Shulman, J., Su, D., Barreiro, F., Leites, A., del Peso, J., Bowler, M., Burrows, P., Veitch, M., Forden, G., Hart, J., Saxon, D., Brandt, S., Holder, M., Eisenberg, Y., Karshon, U., Mikenberg, G., Montag, A., Revel, D., Ronat, E., Shapira, A., Wainer, N., Yekutieli, G., Caldwell, A., Muller, D., Ritz, S., Strom, D., Takashima, M., Wu, Sau, and Zobernig, G.

Abstract

Abstract: We report on an analysis of the multiplicity distributions of charged particles produced ine + e – annihilation into hadrons at c.m. energies between 14 and 46.8 GeV. The charged multiplicity distributions of the whole event and single hemisphere deviate significantly from the Poisson distribution but follow approximate KNO scaling. We have also studied the multiplicity distributions in various rapidity intervals and found that they can be well described by the negative binomial distribution only for small central intervals. We have also analysed forward-backward multiplicity correlations for different energies and selections of particle charge and shown that they can be understood in terms of the fragmentation properties of the different quark flavours and by the production and decay of resonances. These correlations are well reproduced by the Lund string model.

Published
1989
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32. The production and decay of Tau leptons ine+e− annihilation at PETRA energies

Author

Althoff, M., Braunschweig, W., Kirschfink, F. J., Lübelsmeyer, K., Martyn, H. -U., Rosskamp, P., Schmitz, D., Siebke, H., Wallraff, W., Eisenmann, J., Fischer, H. M., Hartmann, H., Jocksch, A., Knop, G., Kolanoski, H., Kück, H., Mertens, V., Wedemeyer, R., Foster, B., Eskreys, A., Gather, K., Hildebrandt, M., Hultschig, H., Joos, P., Kötz, U., Kowalski, H., Ladage, A., Löhr, B., Lüke, D., Mättig, P., Notz, D., Nowak, R. J., Pyrlik, J., Ronat, E., Rushton, M., Schütte, W., Trines, D., Tymieniecka, T., Wolf, G., Yekutieli, G., Xiao, Ch., Fohrmann, R., Hilger, E., Kracht, T., Krasemann, H. L., Leu, P., Lohrmann, E., Pandoulas, D., Poelz, G., Pösnecker, K. U., Wiik, B. H., Beuselinck, R., Binnie, D. M., Campbell, A. J., Dornan, P. J., Garbutt, D. A., Jenkins, C., Jones, T. D., Jones, W. G., McCardle, J., Sedgbeer, J. K., Thomas, J., Wan Abdullah, W. A. T., Bell, K. W., Bowler, M. G., Bull, P., Cashmore, R. J., Clarke, P. E. L., Dauncey, P., Devenish, R., Grossmann, P., Hawkes, C. M., Lloyd, S. L., Mellor, D. J., Youngman, C., Forden, G. E., Hart, J. C., Harvey, J., Hasell, D. K., Saxon, D. H., Woodworth, P. L., Barreiro, F., Brandt, S., Dittmar, M., Holder, M., Kreutz, G., Neumann, B., Duchovni, E., Eisenberg, Y., Karshon, U., Mikenberg, G., Mir, R., Revel, D., Shapira, A., Baranko, G., Caldwell, A., Cherney, M., Izen, J. M., Mermikides, M., Ritz, S., Rudolph, G., Strom, D., Takashima, M., Venkataramania, H., Wicklund, E., Wu, Sau Lan, and Zobernig, G.

Abstract

We have observed t pair production at average CM energies of 13.9, 22.3, 34.5 and 43.1 GeV. The cross-sections are consistent with QED, the cut off parameters being?+>161 GeV and?-169 GeV (95% CL). The topological branching fraction of the t to 1 charged particle,B1, is 0.847±0.011 (stat)-0.013+0.016(syst) and no decays to 5 charged particles were observed resulting inB5<0.007 (95% CL). Within the 3 charged track final stateB(t-?p-p+p-v)/(B(t-?p-p+p-v)+B(t-?p-p+p-p0v))=0.37-0.20+0.35

Published
1985
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33. Photon pair production bye+e− annihilation and search for supersymmetric photinos at energies greater than 40 GeV

Author

Althoff, M., Braunschweig, W., Kirschfink, F. J., Lübelsmeyer, K., Martyn, H. -U., Rosskamp, R., Schmitz, D., Siebke, H., Wallraff, W., Eisenmann, J., Fischer, H. M., Hartmann, H., Jocksch, A., Knop, G., Kolanoski, H., Kück, H., Mertens, V., Wedemeyer, R., Foster, B., Eskreys, A., Gather, K., Hultschig, H., Joos, P., Kötz, U., Kowalski, H., Ladage, A., Löhr, B., Lüke, D., Mättig, P., Notz, D., Nowak, R. J., Pyrlik, J., Rushton, M., Schütte, W., Trines, D., Tymieniecka, T., Wolf, G., Yekutieli, G., Xiao, Ch., Fohrmann, R., Hilger, E., Kracht, T., Krasemann, H. L., Leu, P., Lohrmann, E., Pandoulas, D., Poelz, G., Pösnecker, K. U., Wiik, B. H., Beuselinck, R., Binnie, D. M., Dornan, P. J., Garbutt, D. A., Jenkins, C., Jones, T. D., Jones, W. G., McCardle, J., Sedgbeer, J. K., Thomas, J., Wan Abdullah, W. A. T., Bell, K. W., Bowler, M. G., Bull, P., Cashmore, R. J., Clarke, P. E. L., Dauncey, P., Devenish, R., Grossmann, P., Hawkes, C. M., Lloyd, S. L., Mellor, D. J., Youngman, C., Forden, G. E., Hart, J. C., Harvey, J., Hasell, D. K., Saxon, D. H., Barreiro, F., Brandt, S., Dittmar, M., Holder, M., Kreutz, G., Neumann, B., Duchovni, E., Eisenberg, Y., Karshon, U., Mikenberg, G., Mir, R., Revel, D., Ronat, E., Shapira, A., Winik, M., Baranko, G., Caldwell, A., Cherney, M., Izen, J. M., Mermikides, M., Ritz, S., Rudolph, G., Strom, D., Takashima, M., Venkataramania, H., Wicklund, E., Wu, Sau Lan, and Zobernig, G.

Abstract

The cross section for the processe+e-??? has been measured for c.m. energies 39.5+>61 GeV and ?+> GeV (95% confidence level) have been determined. A search for two photon final states with missing energy provided lower limits on the masses of the photino and selectron.

Published
1984
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34. A measurement of theDs lifetime

Author

Braunschweig, W., Gerhards, R., Kirschfink, F. J., Martyn, H. -U., Rosskamp, P., Bock, B., Eisenmann, J., Fischer, H. M., Hartmann, H., Hilger, E., Jocksch, A., Mertens, V., Wedemeyer, R., Foster, B., Martin, A. J., Sephton, A. J., Bernardi, E., Eisenberg, Y., Eskreys, A., Gather, K., Hultschig, H., Genser, K., Joos, P., Karshon, U., Klima, B., Kowalski, H., Ladage, A., Löhr, B., Lüke, D., Mättig, P., Montag, A., Notz, D., Pawlak, J., Trines, D., Tymieniecka, T., Walczak, R., Wolf, G., Zeuner, W., Kolanoski, A., Kracht, T., Krüger, J., Lohrmann, E., Poelz, G., Poesnecker, K. -U., Binnie, D. M., Sedgbeer, J. K., Shulman, J., Su, D., Watson, A. T., Barreiro, F., Leites, A., del Peso, J., Ros, E., Balkwill, C., Bowler, M. G., Burrows, P. N., Cashmore, R. J., Dauncey, P., Heath, G. P., Mellor, D. J., Ratoff, P., Tomalin, I., Yelton, J. M., Lloyd, S. L., Forden, G. E., Hart, J. C., Hasell, D. K., Saxon, D. H., Brandt, S., Holder, M., Labarga, L., Neumann, B., Mikenberg, G., Mir, R., Revel, D., Ronat, E., Shapira, A., Wainer, N., Yekutieli, G., Baranko, G., Caldwell, A., Cherney, M., Izen, J. M., Muller, D., Ritz, S., Strom, D., Takashima, M., Wicklund, E., Wu, Sau Lan, and Zobernig, G.

Abstract

The lifetime of theDs meson has been measured using the TASSO detector at PETRA and found to be (5.7-2.6+3.6±0.9)×10-13 s. The method used was to reconstruct fully the decay vertex of the channelDs??p±, ??K+K-.

Published
1987
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35. A study of 3-jet events ine+e− annihilation into hadrons at 34.6 GeV c.m. energy

Author

Althoff, M., Braunschweig, W., Kirschfink, F. J., Martyn, H. U., Rosskamp, R., Schmitz, D., siebke, H., Wallraff, W., Eisenmann, J., Fischer, H. M., Hartmann, H., Jocksch, J., Knop, G., Kolanoski, H., Kück, H., Mertens, V., Wedemeyer, R., Foster, B., Wood, A., Bernardi, E., Eisenberg, Y., Eskreys, A., Fohrmann, R., Gather, K., Hultschig, H., Joos, P., Karshon, U., Klima, B., Kötz, U., Kowalski, H., Ladage, A., Löhr, B., Lüke, D., Mättig, P., Mikenberg, G., Notz, D., Pyrlik, J., Schütte, W., Trines, D., Tymieniecka, T., Wolf, G., Zeuner, W., Hilger, E., Kracht, T., Krasemann, H. L., Lohrmann, E., Pandoulas, D., Poelz, G., Pösnecker, K. U., Binnie, D. M., Dornan, P. J., Garbutt, D. A., Jenkins, C., Jones, W. G., Sedgbeer, J. K., Su, D., Thomas, J., Wan Abdullan, W. A. T., Barreiro, F., Labarga, L., Ros, E., Bowler, M. G., Bull, P., Cashmore, R. J., Dauncey, P., Devenish, R., Hawkes, C. M., Heath, G., Mellor, D. J., Lloyd, S. L., Bell, K. W., Forden, G. E., Hart, J. C., Hasell, D. K., Saxon, D. H., Brandt, S., Dittmar, M., Holder, M., Kreutz, G., Neumann, B., Duchovni, E., Montag, A., Mir, R., Revel, D., Ronat, E., Yekutieli, G., Shapira, A., Baranko, G., Caldwell, A., Cherney, M., Hildebrandt, M., Izen, J. M., Mermikides, M., Ritz, S., Rudolph, G., Strom, D., Takashima, M., Venkataramania, H., Wicklund, E., Wu, S. L., and Zobernig, G.

Abstract

Three-jet events produced bye+e- annihilation into hadrons at 34.6 GeV c.m. energy were studied by comparing them with 2nd order QCD and two different models of fragmentation. The distribution of low energy particles in the 3-jet plane is found to be better described by the LUND color string model than by the independent jet model. The opposite is true for more energetic particles flowing between the 3 jets. The average transverse momenta in jets can be described with values of sq between 350 and 500 MeV/c for the gluon jet.

Published
1985
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36. Search for two-photon production of resonances decaying intoK <img src="/fulltext-image.asp?format=htmlnonpaginated&src=T583T72086742VVM_html\10052_2005_Article_BF01550816_TeX2GIFIE1.gif" border="0" alt=" $$\bar K$$ " /> andK <img src="

Author

Althoff, M., Braunschweig, W., Kirschfink, F. J., Martyn, H. -U., Rosskamp, R., Siebke, H., Wallraff, W., Eisenmann, J., Fischer, H. M., Hartmann, H., Jocksch, A., Knop, G., Kolanoski, H., Kück, H., Mertens, V., Wedemeyer, R., Foster, B., Wood, A., Bernardi, E., Eisenberg, Y., Eskreys, A., Gather, K., Hultschig, H., Joos, P., Klima, B., Kowalski, H., Ladage, A., Löhr, B., Lüke, D., Mättig, P., Mikenberg, G., Notz, D., Revel, D., Trines, D., Tymieniecka, T., Walczak, R., Wolf, G., Zeuner, W., Hilger, E., Kracht, T., Krasemann, H. L., Lohrmann, E., Poelz, G., Pösnecker, K. U., Binnie, D. M., Dornan, P. J., Garbutt, D. A., Jenkins, C., Jones, W. G., Sedgbeer, J. K., Su, D., Thomas, J., Wan Abdullah, W. A. T., Barreiro, F., Labarga, L., Ros, E., Bowler, M. G., Bull, P., Cashmore, R. J., Dauncey, P., Devenish, R., Hawkes, C. M., Heath, G., Mellor, D. J., Lloyd, S. L., Bell, K. W., Forden, G. E., Hart, J. C., Hasell, D. K., Saxon, D. H., Brandt, S., Dittmar, M., Holder, M., Kreutz, G., Neumann, B., Duchovni, E., Karshon, U., Montag, A., Mir, R., Ronat, E., Yekutieli, G., Shapira, A., Baranko, G., Caldwell, A., Cherney, M., Hildebrandt, M., Izen, J. M., Mermikides, M., Ritz, S., Strom, D., Takashima, M., Venkataramania, H., Wicklund, E., Wu, S. L., and Zobernig, G.

Abstract

An analysis of the production ofKS0KS0 andK±Ks0π∓ by two quasi-real photons is presented. The cross section forγγ→K0 ", which is given for the γγ invariant mass range fromK " threshold to 2.5 GeV, is dominated by thef′(1525) resonance and an enhancement near theK " threshold. Upper limits on the product of the two-photon width times the branching ratio intoK " pairs are given forΘ(1700),h(2030), and ξ(2220). For exclusive two-photon production ofK±Ks0π∓ no significant signal was observed. Upper limits are given on the cross section ofγγ→K+ "π− orK−K0π+ between 1.4 and 3.2 GeV and on the product of the γγ width times the branching ratio into theK "π final states for theηc(2980) and the ι(1440), yieldingΓ(γγ)→i(1440))·BR(i(1440)→K "π<2.2 keV at 95% C.L.

Published
1985
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37. Determination of αs in first and second order QCD frome+e− annihilation into hadrons

Author

Althoff, M., Braunschweig, W., Kirschfink, F. J., Lübelsmeyer, K., Martyn, H. -U., Rosskamp, P., Sander, H. G., Schmitz, D., Siebke, H., Wallraff, W., Eisenmann, J., Fischer, H. M., Hartmann, H., Jocksch, A., Knop, G., Köpke, L., Kolanoski, H., Kück, H., Mertens, V., Wedemeyer, R., Eskreys, A., Gather, K., Hultschig, H., Joos, P., Kötz, U., Kowalski, H., Ladage, A., Löhr, B., Lüke, D., Mättig, P., Notz, D., Nowak, R. J., Pyrlik, J., Rushton, M., Schütte, W., Trines, D., Tymieniecka, T., Wolf, G., Yekutieli, G., Xiao, Ch., Fohrmann, R., Hilger, E., Kracht, T., Krasemann, H. L., Leu, P., Lohrmann, E., Pandoulas, D., Poelz, G., Pösnecker, K. U., Wiik, B. H., Beuselinck, R., Binnie, D. M., Dornan, P. J., Foster, B., Garbutt, D. A., Jenkins, C., Jones, T. D., Jones, W. G., McCardle, J., Sedgbeer, K. J., Thomas, J., Wan Abdullah, W. A. T., Bell, K. W., Bowler, M. G., Bull, P., Cashmore, R. J., Clarke, P. E. L., Devenish, R., Grossmann, P., Hawkes, C. M., Lloyd, S. L., Youngman, C., Forden, G. E., Hart, J. C., Harvey, J., Hasell, D. K., Saxon, D. H., Barreiro, F., Brandt, S., Dittmar, M., Holder, M., Kreutz, G., Neumann, B., Duchovni, E., Eisenberg, Y., Karshon, U., Mikenberg, G., Mir, R., Revel, D., Ronat, E., Shapira, A., Winik, M., Baranko, G., Barklow, T., Caldwell, A., Cherney, M., Izen, J. M., Mermikides, M., Rudolph, G., Strom, D., Takashima, M., Venkataramania, H., Wicklund, E., Wu, Sau Lan, and Zobernig, G.

Abstract

Multihadron events produced bye+e- annihilation at a c.m. energy of 34.6 GeV have been used to determine as. The predictions of 1 st and 2nd order QCD models with independent jet and string fragmentation have been compared to a large variety of kinematic variables such as event shapes, transverse momentum spectra, jet masses, 3-cluster thrust and the asymmetry of energy-energy correlations. The value of as has been found to depend on the variables used, on the fragmentation model and on the treatment of soft gluons in the 2nd order QCD calculation. Within the models considered as has been found in complete 2nd order QCD to lie between 0.12 and 0.23.

Published
1984
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38. Upper limits on the production rate of the decuplet baryons Δ andΣ* ine+e− annihilation at 34.4 GeV

Author

Althoff, M., Braunschweig, W., Kirschfink, F. J., Lübelsmeyer, K., Martyn, H. -U., Rosskamp, P., Sander, H. G., Schmitz, D., Siebke, H., Wallraff, W., Eisenmann, J., Fischer, H. M., Hartmann, H., Jocksch, A., Knop, G., Köpke, L., Kolanoski, H., Kück, H., Mertens, V., Wedemeyer, R., Eskreys, A., Gather, K., Hultschig, H., Joos, P., Kötz, U., Kowalski, H., Ladage, A., Löhr, B., Lüke, D., Mättig, P., Mess, K. H., Notz, D., Nowak, R. J., Pyrlik, J., Riethmüller, R., Rushton, M., Scütte, W., Trines, D., Tymieniecka, T., Wolf, G., Xiao, Ch., Yekutieli, G., Fohrmann, R., Hilger, E., Kracht, T., Krasemann, H. L., Leu, P., Lohrmann, E., Pandoulas, D., Poelz, G., Pösnecker, K. U., Schmüser, P., Wiik, B. H., Beuselinck, R., Binnie, D. M., Campbell, A. J., Dorman, P. J., Foster, B., Garbutt, D. A., Jenkins, C., Jones, T. D., Jones, W. G., McCardle, J., Sedgbeer, J. K., Thomas, J., Abdullah, W. A. T. Wan, Bell, K. W., Bowler, M. G., Bull, P., Cashmore, R. J., Clarke, P. E. L., Devenish, R., Grossmann, P., Hawkes, C. M., Lloyd, S. L., Youngman, C., Forden, G. E., Hart, J. C., Harvey, J., Hasell, D. K., Saxon, D. H., Woodworth, P. L., Barreiro, F., Brandt, S., Dittmar, M., Holder, M., Kreutz, G., Neumann, B., Duchovni, E., Eisenberg, Y., Karshon, U., Mikenberg, G., Mir, R., Revel, D., Ronat, E., Shapira, A., Winik, M., Baranko, G., Caldwell, A., Cherney, M., Izen, J. M., Mermikides, M., Ritz, S., Rudolph, G., Strom, D., Takashima, M., Venkataramania, H., Wicklund, E., Wu, Sau Lan, and Zobernig, G.

Abstract

Samples of ~1,900 identified protons and ~500 ? have been used to search for decuplet baryon production ine+e- annihilation at a c.m. energy of 34.4 GeV. Thep p+ and ? p± invariant mass spectra contain no ? orS* signals. Upper limits, at 95% confidence level, are that less than 12% of allp and less than 26% of all ? come from the decay of doubly charged ? and singly chargedS* states respectively. These limits correspond to production rates of <0.10?++ and <0.09S*± per event (inclusive of anti-particles). Production of the decuplet states?++ andS*± is suppressed by a factor ?9 relative to octet baryons of the same strangeness.

Published
1984
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39. A measurement of muon pair production ine+e−annihilation at centre of mass energies $$35.0 \leqq \sqrt s \leqq 46.8$$ GeV

Author

Braunschweig, W., Gerhards, R., Kirschfink, F., Martyn, H., Bock, B., Fischer, H., Hartmann, H., Hartmann, J., Hilger, E., Jocksch, A., Wedemeyer, R., Foster, B., Martin, A., Sephton, A., Bernardi, E., Chwastowski, J., Eskreys, A., Gather, K., Genser, K., Hultschig, H., Joos, P., Kowalski, H., Ladage, A., Löhr, B., Lüke, D., Mättig, P., Notz, D., Pawlak, J., Pösnecker, K., Ros, E., Trines, D., Walczak, R., Wolf, G., Kolanoski, H., Kracht, T., Krüger, J., Lohrmann, E., Poelz, G., Zeuner, W., Hassard, J., Shulman, J., Su, D., Barreiro, F., Hervas, L., Leites, A., Peso, J., Traseira, M., Balkwill, C., Bowler, M., Burrows, P., Cashmore, R., Hawkes, C., Heath, G., Ratoff, P., Silvester, I., Tomalin, I., Veitch, M., Forden, G., Hart, J., Saxon, D., Brandt, S., Holder, M., Labarga, L., Duchovni, E., Eisenberg, Y., Karshon, U., Mikenberg, G., Montag, A., Revel, D., Ronat, E., Wainer, A., Yekutieli, G., Muller, D., Ritz, S., Strom, D., Takashima, M., Wu, Sau, and Zobernig, G.

Published
1989
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