排序方式: 共有27条查询结果,搜索用时 12 毫秒
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N. P. Hessey E. C. Booth W. J. Fickinger K. P. Gall M. D. Hasinoff D. Horváth J. Lowe E. K. McIntyre D. F. Measday J. P. Miller A. J. Noble B. L. Roberts D. K. Robinson M. Sakitt M. Salomon D. A. Whitehouse 《Zeitschrift fur Physik C Particles and Fields》1989,42(2):175-183
We have measured the weak radiative decay branching ratio (∑ + →pγ)/(∑ + →pπ0). The experiment was carried out at Brookhaven National Laboratory using a low-energy separatedK ? beam stopping in liquid hydrogen. The∑ + was tagged by observing the pion fromK ? K + p→∑ +π? in a range telescope, and the gamma was detected in a segmented NaI detector. The result is (2.81±0.39 ?0.43 +0.21 )×10?3, which is consistent with previous measurements. This corresponds to a branching ratio for (∑ + →pγ)/(∑ + → all) of (1.45±0.20 ?0.22 +0.11 )×10?3, where the quoted errors are statistical and systematic, respectively. A total of 408 signal events were observed, doubling the previous world total. 相似文献
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L. Adiels G. Alberis G. Backenstoss P. Blüm I. Bergström K. Fransson R. Guigas M. Hasinoff H. Koch A. Kerek M. Meyer P. Pavlopoulos H. Poth U. Raich B. Richter J. Repond M. Suffert L. Tauscher D. Tröster K. Zioutas 《Zeitschrift fur Physik C Particles and Fields》1984,21(4):315-319
The low-energy part of theπ 0 spectrum associated with \(p\bar p\) annihilation at rest was measured in order to search for bound baryonium-like states. The upper limit for reaching such states via the emission of monochromaticπ 0's was found to be 8% per annihilation in the mass region of 1650 MeV. The low-energy part of the η spectrum from \(p\bar p\) annihilations at rest was also observed. 相似文献
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Jonkmans G Ahmad S Armstrong DS Azuelos G Bertl W Blecher M Chen CQ Depommier P Doyle BC von Egidy T Gorringe TP Gumplinger P Hasinoff MD Healey D Larabee AJ Macdonald JA McDonald SC Munro M Poutissou J Poutissou R Robertson BC Sample DG Saettler E Sigler CM Taylor GN Wright DH Zhang NS 《Physical review letters》1996,77(22):4512-4515
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Smith SI Guziec LJ Guziec FS Hasinoff BB Brodbelt JS 《Journal of mass spectrometry : JMS》2007,42(5):681-688
Binding interactions of a new series of anthrapyrazoles (APs) with DNA were evaluated by electrospray ionization mass spectrometry (ESI-MS). Relative binding affinities were estimated from the ESI-MS data based on the fraction of bound DNA for DNA/anthrapyrazole mixtures, and they show a correlation to the shift in melting point of the DNA measured from a previous study. Minimal sequence specificity was observed for the series of anthrapyrazoles. Upon collisionally activated dissociation of the duplex/anthrapyrazole complexes, typically ejection of the ligand was the dominant pathway for most of the complexes. However, for complexes containing AP2 or mitoxantrone, strand separation with the ligand remaining on one of the single strands was observed, indicative of a different binding mode or stronger binding. 相似文献
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Bayes R Bueno JF Hillairet A Davydov YI Depommier P Faszer W Gagliardi CA Gaponenko A Gill DR Grossheim A Gumplinger P Hasinoff MD Henderson RS Hu J Koetke DD MacDonald RP Marshall GM Mathie EL Mischke RE Olchanski K Olin A Openshaw R Poutissou JM Poutissou R Selivanov V Sheffer G Shin B Stanislaus TD Tacik R Tribble RE;TWIST Collaboration 《Physical review letters》2011,106(4):041804
The TWIST Collaboration has completed a new measurement of the energy-angle spectrum of positrons from the decay of highly polarized muons. A simultaneous measurement of the muon decay parameters ρ, δ, and P(μ)(π)ξ tests the standard model in a purely leptonic process and provides improved limits for relevant extensions to the standard model. Specifically, for the generalized left-right symmetric model |(g(R)/g(L))ζ|<0.020 and (g(L)/g(R))m(2)>578 GeV/c(2), both 90% C.L. 相似文献