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Energy scan for narrow states in e+e- annihilation at C.M. energies between 29.90 and 31.46 GeV

Physics Letters B 88:1-2 (1979) 199-202

Authors:

R Brandelik, W Braunschweig, K Gather, V Kadansky, K Lübelsmeyer, P Mättig, HU Martyn, G Peise, J Rimkus, HG Sander, D Schmitz, A Schultz von Dratzig, D Trines, W Wallraff, H Boerner, HM Fischer, H Hartmann, E Hilger, W Hillen, G Knop, P Leu, B Löhr, R Wedemeyer, N Wermes, M Wollstadt, DG Cassel, D Heyland, H Hultschig, P Joos, W Koch, P Koehler, U Kötz, H Kowalski, A Ladage, D Lüke, HL Lynch, G Mikenberg, D Notz, J Pyrlik, R Riethmüller, M Schliwa, P Söding, BH Wiik, G Wolf, R Fohrmann, M Holder, G Poelz, J Ringel, O Römer, R Rüsch, P Schmüser, DM Binnie, PJ Dornan, NA Downie, DA Garbutt, WG Jones, SL Lloyd, D Pandoulas, J Sedgbeer, S Yanker, C Youngman, RJ Barlow, RJ Cashmore, J Illingworth, M Ogg, B Roe, GL Salmon, KW Bell, W Chinowsky, B Foster, JC Hart, J Proudfoot, DR Quarrie, DH Saxon, PL Woodworth, Y Eisenberg, U Karshon, D Revel, E Ronat, A Shapira, J Freeman, P Lecomte, T Meyer, S Lan Wu, G Zobernig

Abstract:

A fine energy scan has been performed to search for narrow states in e+e- annihilation at c.m. energies between 29.90 and 31.46 GeV. No such state has been observed. The 90% confidence upper limit on the leptonic decay width times the hadronic decay branching ratio is ΓeeBh<1.6 keV. © 1979.
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Backward axial vector meson production at intermediate energy

Nuclear Physics, Section B 157:1 (1979) 153-169

Authors:

AC Irving, P Gavillet, C Dionisi, M Mazzucato, B Foster, MR Pennington

Abstract:

We analyse the recent data on backward axial vector meson production which come predominantly from a large K-p bubble chamber experiment at 4.2 GeV/c. In an attempt to understand the production mechanisms, we study the isospin and SU(3) structure of A1, B, D(1285) and C(1280) production and compare this with the corresponding production of pseudoscalar, vector and tensor mesons in the backward direction. The isospin and SU(3) study shows that octet exchange is dominant but there are indications that other exchanges, lower-lying than the nucleon (Nα) trajectory, must also be important. We show that a consistent description of backward resonance production is possible, but further experiments are required to confirm this. © 1979.
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SU(3) implications of the observation of the A1 and C mesons

Nuclear Physics, Section B 156:3 (1979) 532-547

Authors:

M Mazzucato, MR Pennington, R Armenteros, C Dionisi, P Gavillet, A Gurtu, JC Kluyver, GF Wolters, RT Van De Walle, JSM Vergeest, M Zralek, B Foster, WL Mc Dowell, J Wells

Abstract:

A new determination of the QA-QB mixing angle and of the antisymmetric coupling for the vector-pseudoscalar decay of the axial vector mesons is presented. This uses information from the decay rates of the A1 and C mesons found in the study of baryon exchange processes in K-p interactions at 4.2 GeV/c combined with the decay rate B → ωπ. The consistency between the results obtained from backward produced A1 and C and diffractively produced Q1 and Q2 is discussed. © 1979.
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Properties of hadron final states in e+e- annihilation at 13 GeV and 17 GeV center of mass energies

Physics Letters B 83:2 (1979) 261-266

Authors:

R Brandelik, W Braunschweig, K Gather, B Jaax, V Kadansky, K Lübelsmeyer, HU Martyn, G Peise, J Rimkus, HG Sander, D Schmitz, A Schultz von Dratzig, D Trines, W Wallraff, H Boerner, HM Fischer, H Hartmann, E Hilger, W Hillen, G Knop, W Korbach, B Löhr, F Roth, W Rühmer, R Wedemeyer, N Wermes, M Wollstadt, R Bühring, D Heyland, H Hultschig, P Joos, W Koch, U Kötz, H Kowalski, A Ladage, D Lüke, HL Lynch, G Mikenberg, D Notz, J Pyrlik, R Riethmüller, M Schliwa, P Söding, BH Wiik, G Wolf, R Fohrmann, G Poelz, J Ringel, O Römer, R Rüsch, P Schmüser, DM Binnie, PJ Dornan, NA Downie, DA Garbutt, WG Jones, SL Lloyd, D Pandoulas, C Youngman, RJ Barlow, RJ Cashmore, J Illingworth, M Ogg, GL Salmon, KW Bell, W Chinowsky, B Foster, JC Hart, J Proudfoot, DR Quarrie, DH Saxon, PL Woodworth, Y Eisenberg, U Karshon, E Kogan, D Revel, E Ronat, A Shapira, J Freeman, P Lecomte, T Meyer, SL Wu, G Zobernig

Abstract:

We have observed e+e- hadrons at C.M. energies of 13 GeV and 17 GeV at PETRA using the TASSO detector. We find R(13 GeV) = 5.6 ± 0.7 and R(17 GeV) = 4.0 ± 0.7. The additional systematic uncertainty is 20%. Comparing inclusive charged hadron spectra we observe scaling between 5 GeV and 17 GeV for x = p/pbeam > 0.2; however the 13 GeV cross section is above the 17 GeV cross section for smaller x. This may be due to copious bb̄ production. The events become increasingly jet like at high energies as evidenced by a shrinking sphericity distribution with increasing energy. © 1979.
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The reactions K- + p → pseudoscalar meson + Λ (1520) at 4.2 GeV/c

Nuclear Physics, Section B 149:2 (1979) 220-236

Authors:

SJM Barlag, R Blokzijl, B Jongejans, JC Kluyver, GGG Massaro, M Aguilar-Benitez, RJ Hemingway, SO Holmgren, MJ Losty, WJ Metzger, DJ Schotanus, JJ Timmermans, B Foster, P Grossmann, J Wells

Abstract:

The total and differential cross sections of the reactions K-p → π0Λ (1520), ηΛ(1520) and η′ Λ(1520) have been measured. Prominent forward peaks are onserved in all three reactions. The first reaction shows also a backward peak. The spin density matrix elements of the Λ(1520) in this reaction are determined. For forward production the results show a remarkable alignment of the Λ(1520) corresponding to an M2 transition in the model of Stodolsky-Sakurai for 3 2- baryon production. © 1979.
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