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91.
S. Abd El-Samad R. Bilger K. -Th. Brinkmann H. Clement M. Dietrich E. Doroshkevich S. Dshemuchadse K. Ehrhardt A. Erhardt W. Eyrich A. Filippi H. Freiesleben M. Fritsch R. Geyer A. Gillitzer J. Hauffe D. Hesselbarth R. Jaekel B. Jakob L. Karsch K. Kilian J. Kress E. Kuhlmann S. Marcello S. Marwinski R. Meier K. M?ller H. P. Morsch L. Naumann J. Ritman E. Roderburg P. Sch?nmeier M. Schulte-Wissermann W. Schroeder F. Stinzing G. Y. Sun J. W?chter G. J. Wagner M. Wagner U. Weidlich A. Wilms S. Wirth G. Zhang P. Zupranski 《The European Physical Journal A - Hadrons and Nuclei》2009,39(3):281-289
The single-pion production reactions pp
d
, pp
np
and pp
pp
were measured at a beam momentum of 0.95GeV/c ( T
p
400 MeV) using the short version of the COSY-TOF spectrometer. The central calorimeter provided particle identification,
energy determination and neutron detection in addition to time-of-flight and angle measurements from other detector parts.
Thus all pion production channels were recorded with 1-4 overconstraints. The main emphasis is put on the presentation and
discussion of the np
channel, since the results on the other channels have already been published previously. The total and differential cross-sections
obtained are compared to theoretical calculations. In contrast to the pp
channel we observe in the np
channel a strong influence of the excitation. In particular, the pion angular distribution exhibits a (3 cos2
+ 1) -dependence, typical for a pure s -channel excitation and identical to that observed in the d
channel. Since the latter is understood by a s -channel resonance in the 1
D
2
pn partial wave, we discuss an analogous scenario for the pn
channel. 相似文献
92.
S. Abd El-Samad R. Bilger K. -Th. Brinkmann H. Clement M. Dietrich E. Doroshkevich S. Dshemuchadse A. Erhardt W. Eyrich A. Filippi H. Freiesleben M. Fritsch R. Geyer A. Gillitzer J. Hauffe D. Hesselbarth R. Jaekel B. Jakob L. Karsch K. Kilian H. Koch J. Kress E. Kuhlmann S. Marcello S. Marwinski R. Meier K. Möller H. P. Morsch L. Naumann E. Roderburg P. Schönmeier M. Schulte-Wissermann W. Schroeder M. Steinke F. Stinzing G. Y. Sun J. Wächter G. J. Wagner M. Wagner U. Weidlich A. Wilms S. Wirth G. Zhang P. Zupranski 《The European Physical Journal A - Hadrons and Nuclei》2006,30(2):443-453
The single-pion production reactions pp → dπ+, pp → npπ+ and pp → ppπ0 were measured at a beam momentum of 0.95GeV/c ( T
p ≈ 400MeV) using the short version of the COSY-TOF spectrometer. The implementation of a central calorimeter provided particle
identification, energy determination and neutron detection in addition to time-of-flight and angle measurements. Thus, all
pion production channels were recorded with 1-4 overconstraints. The total and differential cross-sections obtained are compared
to previous data and theoretical calculations. Main emphasis is put on the discussion of the ppπ0 channel, where we obtain angular distributions different from previous experimental results, however, partly in good agreement
with recent phenomenological and theoretical predictions. In particular, we observe very large anisotropies for the π0 angular distributions in the kinematical region of small relative proton momenta revealing there a dominance of proton spinflip
transitions associated with π0
s and d partial waves and emphasizing the important role of π0
d-waves. 相似文献
93.
The strong Chebyshev distribution and the Chebyshev orthogonal Laurent polynomials are examined in detail. Explicit formulas are derived for the orthogonal Laurent polynomials, uniform convergence of the associated continued fraction is established, and the zeros of the Chebyshev L-polynomials are given. This provides another well-developed example of a sequence of orthogonal L-polynomials 相似文献
94.
Frequency-resolved optical gating is used to characterize the propagation of intense femtosecond pulses in a nonlinear, dispersive medium. The combined effects of diffraction, normal dispersion, and cubic nonlinearity lead to pulse splitting. The role of the phase of the input pulse is studied. The results are compared with the predictions of a three-dimensional nonlinear Schr?dinger equation. 相似文献
95.
96.
97.
98.
99.
Annabelle Scarpaci Clement Cabanetos Errol Blart Véronique Montembault Laurent Fontaine Vincent Rodriguez Fabrice Odobel 《Journal of polymer science. Part A, Polymer chemistry》2009,47(21):5652-5660
A one‐pot synthetic route based on copper‐catalyzed Huisgen reaction has been developed to functionalize a methacrylate propargylic polymer with azido‐substituted moieties. This procedure was used for the preparation of electro‐optic materials containing well‐known Disperse Red One (DR1) chromophores along with bulky adamantyl moieties (Adam). The postfunctionalization of the propargylic polymer was successfully achieved using different molar ratios of DR1/Adam. These novel polymers exhibit high glass transition temperature owing to the rigid structure of adamantyl units. Moreover, the second harmonic generation measurements demonstrated the effectiveness of adamantyl groups to act as insulating shield limiting thus the electrostatic interactions between chromophores. Indeed, higher optimal chromophore concentration (50 mol %) than in conventional DR1‐containing polymers (30 mol %) allowed us to increase the d33 coefficient up to 92 pm/V. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 5652–5660, 2009 相似文献
100.
M. Abdel-Bary S. Abdel-Samad R. Bilger K.-Th. Brinkmann H. Clement S. Dshemuchadse E. Dorochkevitch H. Dutz W. Eyrich A. Erhardt D. Filges A. Filippi H. Freiesleben M. Fritsch R. Geyer A. Gillitzer D. Hesselbarth B. Jakob L. Karsch K. Kilian H. Koch J. Kreß E. Kuhlmann S. Marcello S. Marwinski S. Mauro W. Meyer P. Michel K. Möller H. P. Morsch L. Naumann N. Paul M. Richter E. Roderburg M. Rogge A. Schamlott M. Schmitz P. Schönmeier M. Schulte-Wissermann W. Schroeder T. Sefzick F. Stinzing G.Y. Sun G.J. Wagner M. Wagner A. Wilms P. Wintz S. Wirth P. Zupranski 《The European Physical Journal A - Hadrons and Nuclei》2003,16(1):127-137
The reaction pp → ppη was measured at excess energies of 15 and 41 MeV at an external target of the Jülich Cooler Synchrotron COSY with the time-of-flight
spectrometer. About 25000 events were measured for the excess energy of 15 MeV and about 8000 for 41 MeV. Both protons of
the process ppη were detected with an acceptance of nearly 100% and the η was reconstructed by the missing-mass technique. For both excess
energies the angular distributions are found to be nearly isotropic. In the invariant-mass distributions strong deviations
from the pure phase space distributions are seen.
Received: 24 May 2002 / Accepted: 20 September 2002 / Published online: 17 January 2003
RID="a"
ID="a"e-mail: e.roderburg@fz-juelich.de
Communicated by M. Gar?on 相似文献