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41.
The current status of the search for localized domains of disoriented chiral condensates (DCC) in Pb+Pb collisions at 158A GeV/c are presented. A new method based on the discrete wavelet transformation (DWT) technique along with an analysis of correlation between charged and neutral particles has been used for the search of localized DCC domains. We show that both the methods indicate the presence of non-statistical fluctuations in data. 相似文献
42.
A CO(2) laser extraction system is described for in situ delta(13)C analysis of organic and inorganic materials. Carbonaceous compounds volatilized by the laser are quantitatively converted to CO(2) gas by a combustion furnace mounted after the sample chamber. Gases produced by the laser and combustion processes are swept by helium carrier gas and separated by a packed gas chromatography column prior to their introduction to an isotope ratio monitoring mass spectrometer. A sample of lentil bean was analyzed at a spatial resolution of 200 μm and yielded delta(13)C values with precision of +/- 0.3 per thousand. The accuracy of delta(13)C measurements was better than +/- 0.5 per thousand from NBS 22 (mineral oil), USGS 24 (graphite), and IAEA CO-1 (calcium carbonate). Copyright 1999 John Wiley & Sons, Ltd. 相似文献
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44.
Wenzhe Fan Yu Zhang Peter W. Carr Sarah C. Rutan Melanie Dumarey Adam P. Schellinger Wayne Pritts 《Journal of chromatography. A》2009,1216(38):6587-6599
Fourteen judiciously selected reversed phase columns were tested with 18 cationic drug solutes under the isocratic elution conditions advised in the Snyder–Dolan (S–D) hydrophobic subtraction method of column classification. The standard errors (S.E.) of the least squares regressions of log k′ vs. log k′REF were obtained for a given column against a reference column and used to compare and classify columns based on their selectivity. The results are consistent with those obtained with a study of the 16 test solutes recommended by Snyder and Dolan. To the extent these drugs are representative, these results show that the S–D classification scheme is also generally applicable to pharmaceuticals under isocratic conditions. That is, those columns judged to be similar based on the 16 S–D solutes were similar based on the 18 drugs; furthermore those columns judged to have significantly different selectivities based on the 16 S–D probes appeared to be quite different for the drugs as well. Given that the S–D method has been used to classify more than 400 different types of reversed phases the extension to cationic drugs is a significant finding. 相似文献
45.
P. Marage M. Aderholz P. Allport N. Armenise J. P. Baton M. Berggren D. Bertrand V. Brisson F. W. Bullock W. Burkot M. Calicchio E. F. Clayton T. Coghen A. M. Cooper-Sarkar O. Erriquez P. J. Fitch J. Guy F. Hamisi P. O. Hulth G. T. Jones P. Kasper U. F. Katz H. Klein E. Matsinos R. P. Middleton D. B. Miller M. M. Mobayyen D. R. O. Morrison M. Neveu S. W. O'Neale M. A. Parker P. Petiau J. Sacton R. A. Sansum N. Schmitz E. Simopoulou C. Vallée K. Varvell A. Vayaki W. Venus H. Wachsmuth J. Wells W. Wittek BEBC WA Collaboration 《Zeitschrift fur Physik C Particles and Fields》1987,35(3):275-282
Coherent production ofρ ? mesons in charged current antineutrino interactions on neon nuclei is studied in the BEBC bubble chamber exposed to the CERN SPS wide band beam. The cross section is measured to be (95±25)·10?40 cm2 per neon nucleus, averaged over the beam energy spectrum. The distributions of kinematical variables and the absolute value of the cross section are in agreement with theoretical predictions based on the CVC hypothesis and the vector meson dominance model. 相似文献
46.
P. J. Fitch P. Kasper A. M. Cooper-Sarkar M. Aderholz N. Armenise T. Azemoon D. Bertrand M. Berggren F. W. Bullock M. Calicchio E. F. Clayton T. Coghen O. Erriquez G. Gerbier J. Guy P. O. Hulth G. Iaselli G. T. Jones M. Lagraa P. Marage R. P. Middleton D. Miller M. M. Mobayyen M. Neveu S. W. O'Neale M. A. Parker R. A. Sansum E. Simopoulou K. Varvell C. Vallée A. Vayaki W. Venus H. Wachsmuth W. Wittek J. Wells E. Zevgolatakos BEBC WA Collaboration 《Zeitschrift fur Physik C Particles and Fields》1986,31(1):51-58
Evidence for a significant higher twist contribution to highz π? production in antineutrino scattering is presented. In events withW>3 GeV andQ 2>1 GeV2 in our data, it accounts for (51 ±8)% of all π? withz above 0.5. It is consistent with thez?Q 2 correlations of Berger's higher twist prediction. The data are inconclusive concerning the predictedy?z correlation andp T dependence. Thez ?Q 2 correlation is not adequately described by the Lund Monte-Carlo. 相似文献
47.
We have measured the polarization of ∧ and Ξ? hyperons produced inclusively by a Σ? beam of 340 GeV/c momentum in nuclear targets, using samples of 9.5 million ∧ decays and 880000 Ξ? decays. The large statistics allowed a two-dimensional analysis as functions ofx F andp t . The polarization w.r.t. the production normal is mainly positive for ∧ and negative for Ξ?. The positive sign of the ∧ polarization is opposite to predictions. Atp t >1 Gev/c, the ∧ polarization decreases to zero or even negative values, in sharp contrast to the plateau abovep t <1 GeV/c observed in inclusive ∧ production by protons. No such effect is observed for the Ξ? polarization, and its sign is as expected. 相似文献
48.
R. Albrecht T. C. Awes C. Baktash P. Beckmann F. Berger R. Bock G. Claesson G. Clewing L. Dragon A. Eklund R. L. Ferguson A. Franz S. Garpman R. Glasow H. ?. Gustafsson H. H. Gutbrod J. Idh P. Jacobs K. H. Kampert B. W. Kolb P. Kristiansson I. Y. Lee H. L?hner I. Lund F. E. Obenshain A. Oskarsson I. Otterlund T. Peitzmann S. Persson F. Plasil A. M. Poskanzer M. Purschke H. G. Ritter S. Saini R. Santo H. R. Schmidt T. Siemiarczuk S. P. Sorenseh E. Stenlund M. Tincknell G. R. Young WA -Collaboration 《Zeitschrift fur Physik C Particles and Fields》1990,45(4):529-537
Charged pion yields and transverse energies of baryons are measured for the reaction16O+Cu, Ag, Au at 60 and 200A GeV bombarding energy in the target fragmentation region employing the Plastic Ball detector. Only little dependence of the measured quantities on the bombarding energy is found. The data are compared with the multi-chain fragmentation model of Ranft. As a result it turns out that a leading order formation zone cascade is not sufficient to explain the baryon yield and the transverse energies of baryons in the target fragmentation region. 相似文献
49.
M. Bonesini E. Bonvin P. S. L. Boóth D. Bortoletto L. J. Carroll A. J. Cass D. Cavalli G. Costa M. Donnat P. A. Dorsaz D. N. Edwards J. R. Fischer L. Fluri D. Frame F. Gianotti S. Jack J. N. Jackson M. Kelly M. N. Kienzle-Focacci R. Lucock J. G. Lynch L. Mandelli M. Martin L. Mathys A. Maxwell M. Mazzanti J. J. Myerscough P. J. Negus S. Pensotti-Rancoita L. Perini D. Perrin G. Polesello W. H. Range L. Rosselet S. W. Snow M. Tamborini A. S. Thompson R. M. Turnbull J. Wells M. Werlen WA -Collaboration 《Zeitschrift fur Physik C Particles and Fields》1988,37(4):535-544
The inclusive cross sections for prompt photon production by π? and π+ on protons have been measured with a beam momentum of 280 GeV/c using a fine grained electromagnetic calorimeter and the CERN Omega spectrometer. The transverse momentum and Feynmanx F ranges covered are 4.0<p T <7.0GeV/c and ?0.45<x F <0.55 respectively. A quantitative comparison of the prompt photon cross section with next-to-leading order QCD predictions using Duke and Owens structure functions is performed. 相似文献
50.
R. Albrecht T. C. Awes C. Baktash P. Beckmann F. Berger R. Bock G. Claesson L. Dragon R. L. Ferguson A. Franz S. Garpmann R. Glasow H. A. Gustafsson H. H. Gutbrod K. H. Kampert B. W. Kolb P. Kristiansson I. Y. Lee H. Lohner I. Lund F. E. Obenshain A. Oskarsson I. Otterlund T. Peitzmann S. Persson F. Plasil A. M. Poskanzer M. Purschke H. G. Ritter R. Santo H. R. Schmidt T. Siemiarczuk S. P. Sorensen E. Stenlund G. R. Young WA Collaboration 《Zeitschrift fur Physik C Particles and Fields》1988,38(1):3-14
Results based on calorimetric measurements are presented from reactions of 60A GeV and 200A GeV16O projectiles with C, Cu, Ag, and Au nuclei. Minimum-bias cross sections are discussed. Energy spectra measured at zero degrees and transverse-energy distributions for the pseudorapidity range 2.4≦η≤5.5 are shown. An analysis of the average transverse energy in terms of the number of participating nucleons and the number of binary nucleon-nucleon collisions is presented. Estimates of nuclear stopping and of attained energy densities are made. 相似文献