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131.
The ZEUS Collaboration S. Chekanov et al. 《The European Physical Journal C - Particles and Fields》2002,25(2):169-187
Diffractive dissociation of virtual photons, , has been studied in ep interactions with the ZEUS detector at HERA. The data cover photon virtualities 0.17 < Q
2
< 0.70 GeV2 and 3 < Q
2
< 80 GeV2 with 3 < MX < 38 GeV, where MX is the mass of the hadronic final state. Diffractive events were selected by two methods: the first required the detection
of the scattered proton in the ZEUS leading proton spectrometer (LPS); the second was based on the distribution of MX. The integrated luminosities of the low- and high-Q2 samples used in the LPS-based analysis are 0.9 pb-1 and 3.3 pb-1, respectively. The sample used for the MX-based analysis corresponds to an integrated luminosity of 6.2 pb-1. The dependence of the diffractive cross section on W, the virtual photon-proton centre-of-mass energy, and on Q2 is studied. In the low-Q2 range, the energy dependence is compatible with Regge theory and is used to determine the intercept of the Pomeron trajectory.
The W dependence of the diffractive cross section exhibits no significant change from the low-Q2 to the high-Q2 region. In the low-Q2 range, little Q2 dependence is found, a significantly different behaviour from the rapidly falling cross section measured for Q
2
> 3 GeV2. The ratio of the diffractive to the virtual photon-proton total cross section is studied as a function of W and Q2. Comparisons are made with a model based on perturbative QCD.
Received: 27 March 2002 / Published online: 9 August 2002 相似文献
132.
The qq+q Collaboration F. Farchioni et al. 《The European Physical Journal C - Particles and Fields》2002,26(2):237-251
Two degenerate flavors of quarks are simulated with small masses down to about one fifth of the strange quark mass by using
the two-step multi-boson (TSMB) algorithm. The lattice size is with lattice spacing about which is not far from the N
t
=4 thermodynamical cross-over line. Autocorrelations of different physical quantities are estimated as a function of the quark
mass. The eigenvalue spectra of the Wilson-Dirac operator are investigated.
Received: 20 June 2002 / Revised version: 30 August 2002 / Published online: 25 October 2002 相似文献
133.
掺杂石英系单模光纤对BSBS频移的影响 总被引:1,自引:0,他引:1
报道了对几种掺杂SiO2石英系单模光纤的背向受激布里渊散射(BSBS)谱的实验结果,结果表明其布里渊散射斯托克斯频移主要取决于纤芯的掺杂材料和浓度,进一步分析证明了光纤掺杂后将主要通过调制杨氏模量的变化,从而导致BSBS频移量减小. 相似文献
134.
THE ADSORPTION BEHAVIORS OF TOLUENE ON HYPERCROSSLINKED RESINS 总被引:1,自引:0,他引:1
WANG Jingping FEI Zhenghao TANG Shuhe Jiangsu Provincial Key Laboratory of Coastal Wetland Bioresources Environmental Protection Yancheng Teachers College The Institute of Application Chemistry Environmental Engineering Yancheng City Jiangsu Province P. R. China 《Chinese Journal of Reactive Polymers》2005,(Z1)
1. INTRODUCTION Toluene has been widely used for many industrial purposes. Owing to their toxicity and recalcitrance, the presence of toluene in the natural environment, especially in the groundwater, has been a great concern. The removal of toluene is of… 相似文献
135.
试制成功了热平衡时间短的解偏振光强度测定装置,用该装置测定了尼龙66,尼龙6和PET的结晶动力学数据,得到了满意的结果, 相似文献
136.
The Publishers W.H. Abd. Majid 《The European Physical Journal B - Condensed Matter and Complex Systems》2006,52(4):575
In spite of the precautions taken to check the originality of the articles,
it happens, unfortunately that our scientific colleagues' vigilance is sometimes caught up unprepared.
Today, it has come to our attention that
the following article results from a plagiarism.
We apologize to the authors who suffered from it.
You will
find hereafter a note written by Dr Majid which summarizes the situation. 相似文献
137.
The DELPHI Collaboration J. Abdallah et al. 《The European Physical Journal C - Particles and Fields》2003,26(4):505-525
In some supersymmetric models, the gluino () is predicted to be light and stable. In that case, it would hadronize to form R-hadrons. In these models, the missing energy
signature of the lightest supersymmetric particle is no longer valid, even if R-parity is conserved. Therefore, such a gluino
is not constrained by hadron collider results, which looked for the decay . Data collected by the DELPHI detector in 1994 at 91.2 GeV have been analysed to search for events. No deviation from Standard Model predictions is observed and a gluino mass between 2 and 18 GeV/c2 is excluded at the 95% confidence level in these models. Then, R-hadrons produced in the squark decays were searched for
in the data collected by DELPHI at the centre-of-mass energies of 189 to 208 GeV, corresponding to an overall integrated luminosity
of 609 Pb-1. The observed number of events is in agreement with the Standard Model predictions. Limits at 95% confidence level are derived
on the squark masses from the excluded regions in the plane ()
GeV/c2, and GeV/c2 for purely left squarks.
GeV/c2, and GeV/c2 independent of the mixing angle.
Received: 6 November 2002 / Published online: 15 January 2003 相似文献
138.
纳米混合分子聚集体材料中弗兰克尔激子迁移的相位弛豫 总被引:1,自引:0,他引:1
在有机染料PIC-1中引入其衍生物azaPIC-I形成能量势垒,改变在混合分子聚集体中PIC-I的J-聚集体的实体长度。用双调制外差检测的累积光子回波技术研究了相干弗兰克尔激子失相过程。观测到激子失相时间T2随azaPIC-1克分子数的增大从60ps变为224ps。 相似文献
139.
硒的原子吸收分析进展 总被引:16,自引:1,他引:15
米瑞华 《光谱学与光谱分析》1993,13(4):103-110
本文对1985年以来硒的原子吸收分析,从石墨炉法、氢化物法、氢化物-石墨炉法和火焰法四个方面的分析进展进行综合评述。 相似文献
140.
本文介绍了降秩因子(RAFA)方法,它是从一个多组分混合物中直接定量计算其中某一组分,而不必知道其他组分的物种及含量的一种定量分析的数学方法。它适用于双线性的数据。本实验首先将荧光分光光度计与外接计算机相连,以获得样品的激发-发射矩阵(EEM),再用RAFA方法对蒽,萘,菲,芘,芴,Qu六种标样的一至五组分的混合物进行定量分析,获得满意的结果。 相似文献