作者机构：
[Kittel, W] Univ Nijmegen, NIKHEF, High Energy Phys Inst, NL-6525 ED Nijmegen, Netherlands.;Inst Phys, AM-375036 Yerevan, Armenia.;Hua Zhong Normal Univ, Inst Particle Phys, Wuhan 430070, Peoples R China.;Univ Antwerp, Dept Phys, B-2610 Antwerp, Belgium.;Ctr Brasileiro Pesquisas Fis, BR-22290 Rio De Janeiro, Brazil.
通讯机构：
[Kittel, W] U;Univ Nijmegen, NIKHEF, High Energy Phys Inst, NL-6525 ED Nijmegen, Netherlands.
摘要：
The erraticity behavior of multiparticle production is analyzed in pi(+)p and K(+)p collisions at 250 GeV/c. It is demonstrated that, for these low-multiplicity final states, the erraticity measure based on event-to-event fluctuation of factorial moments is dominated by statistical fluctuations. (C) 2003 Elsevier Science B.V. All rights reserved.
期刊：
INTERNATIONAL JOURNAL OF MODERN PHYSICS A,2002年17(31):4669-4673 ISSN：0217-751X
通讯作者：
Liao, HB
作者机构：
[Wu, YF; Liao, HB] Huazhong Normal Univ, Inst Particle Phys, Wuhan 430079, Peoples R China.
通讯机构：
[Liao, HB] H;Huazhong Normal Univ, Inst Particle Phys, Wuhan 430079, Peoples R China.
关键词：
Rapidity gap;stability
摘要：
It is argued that the newly introduced moments of rapidity gaps for the event-by-event fluctuations depends on the number of events and multiplicity. The interesting ones are unstable under ISR energies of h-h collisions. The instability is well improved when multiplicity increases.
作者机构：
[Atayan, MR] Inst Phys, AM-375036 Yerevan, Armenia.;Hua Zhong Normal Univ, Inst Particle Phys, Wuhan 430070, Peoples R China.;Univ Instelling Antwerpen, Dept Phys, B-2610 Antwerp, Belgium.;Ctr Brasileiro Pesquisas Fis, BR-22290 Rio De Janeiro, Brazil.;Univ Nijmegen, NIKHEF, High Energy Phys Inst HEFIN, NL-6525 ED Nijmegen, Netherlands.
摘要：
We report results on event-by-event fluctuations of transverse momentum, Φpt, in π+p and K+p collisions at 250 GeV/c. For the first time, their dependence on rapidity region, transverse momentum acceptance, multiplicity, mean transverse momentum per event, and on the correlation between transverse momentum and multiplicity are systematically presented. The results are compared with those from the PYTHIA Monte Carlo generator. The fluctuations under the same acceptance cuts as used in current heavy-ion experiments are also presented.
作者机构：
[Wu, YF; Liu, LS] Huazhong Normal Univ, Inst Particle Phys, Wuhan 430079, Peoples R China.
通讯机构：
[Wu, YF] H;Huazhong Normal Univ, Inst Particle Phys, Wuhan 430079, Peoples R China.
关键词：
重离子碰撞;最大熵原理;源函数
摘要：
We study the reconstruction of the source function in space-time directly from the measured Hanbury-Brown/Twiss (HBT) correlation function using the maximum entropy principle. We find that the problem is ill-defined without at least one additional theoretical constraint as input. Using the requirement of a finite source lifetime for the problem we find a new Gausslan parametrization of the source function directly in terms of the measured HBT radius parameters and its lifetime, where the latter is a free parameter which is not directly measurable by HBT. We discuss the implications of our results for the remaining freedom in building source models consistent with a given set of measured HBT radius parameters.
期刊：
Modern Physics Letters A,2001年16(9):583-588 ISSN：0217-7323
通讯作者：
Li, ZM
作者机构：
[Wu, YF; Li, ZM; Wang, Q] Huazhong Normal Univ, Inst Particle Phys, Wuhan 430079, Peoples R China.
通讯机构：
[Li, ZM] H;Huazhong Normal Univ, Inst Particle Phys, Wuhan 430079, Peoples R China.
摘要：
The role of wavelet transformation in the study of random processes is investigated. It is shown that wavelet transformation does not change the scaling index of random multiplicative cascade process. On the other hand, for pure random process, wavelet transformation is able to suppress the trivial fluctuations, coming from probability conservation, which will show an apparent increase in moments with the diminishing of bin size.
摘要：
Using Monte Carlo simulation it is shown that in low multiplicity events the single-event factorial moments are saturated by the statistical fluctuations. The diversification of the event-space momentsC
p, q of single-event moments with the diminishing of phase space scale, called “erraticity”, observed in experiment can readily be reproduced by a flat probability distribution with only statistical fluctuations and therefore it has nothing to do with chaos as suggested. The possibility of studying chaos in high multiplicity events using erraticity analysis is discussed.
摘要：
It is demonstrated that in a low-multiplicity sample, the increase of the fluctuation of event factorial moments with decreasing phase-space scale, called “erraticity”, is dominated by the statistical fluctuations. The erraticity behavior observed in the NA27 experiment can be readily reproduced by purely statistical fluctuations. Applying the erraticity analysis to a high-multiplicity sample is, however, recommended and the method is improved for the very-high-multiplicity case.
作者机构：
[Hwa, RC] Univ Oregon, Inst Theoret Sci, Eugene, OR 97403 USA.;Univ Oregon, Dept Phys, Eugene, OR 97403 USA.;Hua Zhong Normal Univ, Inst Particle Phys, Wuhan 430070, Peoples R China.
通讯机构：
[Hwa, RC] U;Univ Oregon, Inst Theoret Sci, Eugene, OR 97403 USA.
摘要：
The critical behaviors of the quark-hadron phase transition are explored by use of the Ising model adapted for hadron production. Various measures involving the fluctuations of the produced hadrons in bins of various sizes are examined with the aim of quantifying the clustering properties that are universal features of all critical phenomena. Some of the measures involve wavelet analysis. Two of the measures are found to exhibit the canonical power-law behavior near the critical temperature. The effect of final-state randomization is studied by requiring the produced particles to take random walks in the transverse plane. It is demonstrated that for the measures considered the dependence on the randomization process is weak. Since temperature is not a directly measurable variable, the average hadronic density of a portion of each event is used as the control variable that is measurable. The event-to-event fluctuations are taken into account in the study of the dependence of the chosen measures on that control variable. Phenomenologically verifiable critical behaviors are found and are proposed for use as a signature of quark-hadron phase transition in relativistic heavy-ion collisions.
作者机构：
[Hwa, RC] Univ Oregon, Inst Theoret Sci, Eugene, OR 97403 USA.;Univ Oregon, Dept Phys, Eugene, OR 97403 USA.;Hua Zhong Normal Univ, Inst Particle Phys, Wuhan 430070, Peoples R China.
通讯机构：
[Hwa, RC] U;Univ Oregon, Inst Theoret Sci, Eugene, OR 97403 USA.
摘要：
The soft production problem in hadronic collisions as described in the eikonal color mutation branching model is improved in the way that the initial parton distribution is treated. Furry branching of the partons is considered as a means of describing the nonperturbative process of parton reproduction in the soft interaction. The values of all the moments, 〈n〉 and Cq, for q=2,…,5, as well as their energy dependences, can be correctly determined by the use of only two parameters.
摘要：
A factorial-moment analysis with real (integer and non-integer) phase space partition is applied to pi(+)p and K(+)p collisions at 250 GeV/c. Clear evidence is shown for self-affine rather than self-similar power-law scaling in multiparticle production. The three-dimensional self-affine second-order scaling exponent is determined to be 0.061 +/- 0.010. (C) 1998 Elsevier Science B.V. All rights reserved.
摘要：
The information on dynamical fluctuations that can be extracted from the anomalous scaling observed recently in hadron-hadron collision experiments is discussed in some detail. A parameter "effective fluctuation strength" is proposed to estimate the strength of dynamical fluctuations. The method for extracting its value from the experimentally observed quantities is given. Some examples for the application of this method to real experimental data are presented. (C) 1998 Elsevier Science B.V. All rights reserved.
作者机构：
[Wiedemann, U.A.] Inst. für Theoretische Physik, Universität Regensburg, D-93040 Regensburg, Germany;Faculty of Mathematics and Physics, Comenius University, Mlynská Dolina, SK-84215 Bratislava, Slovakia;CERN, Theory Division, CH-1211 Geneve, Switzerland;Institute of Particle Physics, Hua-Zhong Normal University, Wuhan, China;[Heinz, U.] Inst. für Theoretische Physik, Universität Regensburg, D-93040 Regensburg, Germany, CERN, Theory Division, CH-1211 Geneve, Switzerland
通讯机构：
[Tomášik, B.] I;Inst. für Theoretische Physik, Universität Regensburg, Germany
摘要：
We present the Yano-Koonin-Podgoretskiǐ parametrisation of the correlation function. Compared to the conventionally used Cartesian parametrisation, this one provides more straightforward measurement of the duration of the emission process in the fireball and a clearer signal of the longitudinal expansion, which is expected in ulrarelativistic heavy ion collisions.
期刊：
PROCEEDINGS OF THE XXVI INTERNATIONAL SYMPOSIUM ON MULTIPARTICLE DYNAMICS,1997年:343-350
通讯作者：
Liu, LS
作者机构：
[Wu, YF; Liu, LS] Huazhong Normal Univ, Inst Particle Phys, Wuhan, Peoples R China.
通讯机构：
[Liu, LS] H;Huazhong Normal Univ, Inst Particle Phys, Wuhan, Peoples R China.
摘要：
It is argued that the scaling property of higher dimensional normalized factorial moments depends essentially on the different ways of phase space division. The later can be characterized by the log ratio of partition number in different directions of phase space. Two examples are given. Firstly, a self-affine analysis of factorial moments was carried out on the NA22 data for pi(+)p and K(+)p collisions at 250 GeV/c. It turns out that the Hurst exponent is only one half when the longitudinal direction is compared to the transverse ones, providing a first experimental evidence on the anisotropy of dynamical fluctuation in multiparticle production. A discussion on the similar analysis for heavy ion collision data is presented as a second example. The experimentally observed strong upward-bending of the logarithm of factorial moments versus that of the phase space partition number in higher-dimensional phase space of nucleus-nucleus collisions is shown to be due to the superposition of elementary collision processes in these collisions. A trigger condition for the search of QGP is proposed basing on this phenomenon.
