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1.
Nernst R Antreasyan D Aschman D Besset D Bienlein JK Bloom ED Brock I Cabenda R Cartacci A Cavalli-Sforza M Clare R Conforto G Cooper S Cowan R Coyne D de Judicibus D Edwards C Engler A Folger G Fridman A Gaiser J Gelphman D Godfrey G Heimlich FH Hofstadter R Irion J Jakubowski Z Keh S Kilian H Kirkbride I Kloiber T Koch W König AC Königsmann K Kraemer RW Lee R Leffler S Lekebusch R Lezoch P Litke AM Lockman W Lowe S Lurz B Marlow D Maschmann W Matsui T Messing F Metzger WJ Monteleoni B 《Physical review letters》1985,54(20):2195-2198
2.
B. Niczyporuk Z. Jakubowski T. Zełudziewicz G. Folger B. Lurz H. Vogel U. Volland H. Wegener J. K. Bienlein R. Graumann H. -J. Trost M. Schmitz F. H. Heimlich R. Nernst A. Schwarz U. Strohbusch P. Zschorsch K. W. Chen A. C. König D. J. Schotanus M. Coles A. Engler R. W. Kraemer D. Marlow F. Messing C. Rippich S. Youssef A. Fridman G. Alexander A. Av-Shalom G. Bella J. Grunhaus W. Langguth M. Scheer LENA Collaboration 《Zeitschrift fur Physik C Particles and Fields》1983,17(3):197-202
A search for the decays γ→ρπ, γ→J/ψX and γ→γa (whereX is undetermined and a is an axion) has been completed using the LENA detector at the DORIS storage ring. No evidence for any of these processes was found. For these decay modes we set branching fraction upper limits (90% C.L.) of 2.1×10?3, 2.0×10?2 and 9.1×10?4, respectively. 相似文献
3.
4.
P. Bock G. Heinzelmann B. Pietrzyk G. Blanar W. Blum H. Dietl E. Lorenz R. Richter J. K. Bienlein M. Leissner B. Niczyporuk C. Rippich M. Schmitz H. Vogel F. H. Heimlich P. Lezoch U. Strohbusch 《Zeitschrift fur Physik C Particles and Fields》1980,6(2):125-129
The total cross section fore + e ? annihilation into hadrons for center of mass energies from 9.4 to 9.5 GeV has been measured with the nonmagnetic DESY-Heidelberg detector at DORIS. A value ofR=σhad/σµµ=3.8±0.7 for the continuum region around the Υ (9.46) resonance has been determined. The ratioΓ ee Γ had/Γ tot of electronic, hadronic and total widths has been reevaluated to be (1.00±0.23) keV for the Υ resonance and (0.37±0.16) keV for the Υ′. In addition, a search for directly produced pohotons from Υ decays of the type Υ→γ+gluon+gluon has been performed. The Υ decay into muon pairs has also been searched for. 相似文献
5.
K. Karch D. Antreasyan H. W. Bartels D. Besset Ch. Bieler J. K. Bienlein A. Bizzeti E. D. Bloom I. Brock K. Brockmüller et al. 《Zeitschrift fur Physik C Particles and Fields》1992,54(1):33-44
The reactione
+
e
- e
+
e
- 00e
+
e
- 6 has been analysed using the full data sample taken with the Crystal Ball detector at the DORIS II storage ring at DESY. The 00 invariant mass spectrum is dominated by the ', for which we determine the radiative width (') to be (4.5±0.3±0.5)keV. Near 1.9 GeV/c2 we observe a second enhancement in the 00 mass distribution. Assuming that these events are created by the production and subsequent decay of a wide resonanceX(1900), we have investigated the decay modes, the invariant mass distributions of the 0 and 00 subsystems and the angular distributions of the final state mesons. We find that the data is best described byJ
PC=2. For thisJ
P assignment the resonance parameters are (X) BR(X)=(0.95±0.27±0.20) keV tot (X)=(221±92±44)MeV, andM(X)=(1881±32±40) MeV/c2.Deceased 相似文献
6.
Marsiske H Antreasyan D Bartels HW Besset D Bieler C Bienlein JK Bizzeti A Bloom ED Brock I Brockmüller K Cabenda R Cartacci A Cavalli-Sforza M Clare R Compagnucci A Conforto G Cooper S Cowan R Coyne D Engler A Fairfield K Folger G Fridman A Gaiser D Gelphman D Glaser G Godfrey G Graaf K Heimlich FH Heinsius FH Hofstadter R Irion J Jakubowski Z Janssen H Karch K Keh S Kiel T Kilian H Kirkbride I Kloiber T Kobel M Koch W König AC Königsmann K Kraemer RW Krüger S Landi G Lee R Leffler S 《Physical review D: Particles and fields》1990,41(11):3324-3335
7.
B. Niczyporuk Z. Jakubowski G. Nowak G. Folger B. Lurz U. Volland H. Wegener J. K. Bienlein R. Graumann H. -J. Trost M. Schmitz F. H. Heimlich R. Nernst A. Schwarz U. Strohbusch P. Zschorsch K. W. Chen A. C. König D. J. Schotanus M. Coles A. Engler R. W. Kraemer D. Marlow F. Messing C. Rippich S. Youssef A. Fridman G. Alexander A. Av-Shalom G. Bella J. Grunhaus M. Scheer LENA Collaboration 《Zeitschrift fur Physik C Particles and Fields》1982,15(4):299-309
The rationR=σ(e + e ?→hadrons)/σ(e + e ?→ µ+ µ?) was measured with the LENA detector at DORIS in a scan between 7.40 and 7.48 GeV and between 8.67 and 9.43 GeV center of mass energies. Corrected for QED radiative effects,R is found to be constant with an average value ofR=3.37 ±0.06stat±0.23syst. No narrow resonances withΓ ee (Γ had/Γ tot)?0.30 keV (95% C.L.) and no steps have been observed. Based on this value ofR, revised values for υ(1S) resonance parameters are presented. 相似文献
8.
P.L. Woodwarth D. Treille A.S. Thompson R. Strub P. Sonderegger C. Palazzi-Cerrina W.A. Mitaroff R. Kumar I.R. Kenyon G. Irwin J.R. Hubbard M. Houlden B.R. French L. Fluri G. De Rosny M. Cribier J.K. Bienlein 《Physics letters. [Part B]》1976,65(1):89-91
We have observed φ production in π?p interactions at 19 GeV/c with (44±10) events in the final state φπ+π?π?p and (45±9) events in φK+K?π?p. The production ratios φπ+π?π?p/ωπ+π?π?p ≈ 0.005 and φK+K?π?p/?°K+K?π?p ≈ 0.45 agree with Zweig-rule expectations. 相似文献
9.
P. Bonamy P. Borgeaud M. Crozon J.P. Guillaud O. Guisan P. Le Du P. Sonderegger J.K. Bienlein S. Mango L. Paul H. Dinter 《Nuclear Physics B》1973,52(2):392-402
Measurements of the polarization parameter of the reactions π?p → π0n and π?p → ηn at 4.90 and 7.85 GeV/c and for a squared four-momentum transfer ?t ranging from 0.1 to 2.0 (GeV/c)2 have been achieved by using a butanol polarized proton target and detecting only the two γ's from the neutral meson decay. The background due to events involving bound protons has been separately measured and subtracted out. A large positive polarization has been found for the reaction π?p → π0n. It is consistent with other pion-nucleon scattering data connected by isospin conservation. The polarization for the reaction π?p → ηn is not significantly different from zero within the large experimental errors. 相似文献
10.
Skwarnicki T Antreasyan D Besset D Bienlein JK Bloom ED Brock I Cabenda R Cartacci A Cavalli-Sforza M Clare R Conforto G Cooper S Cowan R Coyne D Edwards C Engler A Folger G Fridman A Gaiser J Gelphman D Godfrey G Heimlich FH Hofstadter R Irion J Jakubowski Z Keh S Kilian H Kirkbride I Kloiber T Koch W König AC Königsmann K Kraemer RW Lee R Leffler S Lekebusch R Litke AM Lockman W Lowe S Lurz B Marlow D Maschmann W Matsui T Messing F Metzger WJ Monteleoni B Nernst R Niczyporuk B Nowak G Peck C 《Physical review letters》1987,58(10):972-975