Two-dimensional multiplicity fluctuation analysis of target residues in nuclear collisions

Multiplicity fluctuation of the target residues emitted in the interactions in a wide range of projectile energies from 500 A MeV to 60 A GeV is investigated in the framework of two-dimensional scaled factorial moment methodology. The evidence of non-statistical multiplicity fluctuation is found in 160-AgBr collisions at 60 A GeV, but not in 56Fe-AgBr collisions at 500 A MeV, 84Kr-AgBr collisions at 1.7 A GeV, 16O-AgBr collisions at 3.7 A GeV and 197Au-AgBr collisions at 10.7 A GeV.

Forward–backward emission of target evaporated fragments in high energy nucleus–nucleus collisions

The multiplicity distribution, multiplicity moment, scaled variance, entropy and reduced entropy of target evaporated fragments emitted in forward and backward hemispheres in 12 A GeV ^4He, 3.7 A GeV ^16O, 60 A GeV ^16O, 1.7 A GeV ^84Kr and 10.7 A GeV ^197Au -induced emulsion heavy target （AgBr） interactions are investigated. It is found that the multiplicity distribution of target evaporated fragments emitted in both forward and backward hemispheres can be fitted by a Gaussian distribution. The multiplicity moments of target evaporated particles emitted in the forward and backward hemispheres increase with the order of the moment q, and the secondorder multiplicity moment is energy independent over the entire energy range for all the interactions in the forward and backward hemisphere. The scaled variance, a direct measure of multiplicity fluctuations, is close to one for all the interactions, which indicate a correlation among the produced particles. The entropy of target evaporated fragments emitted in both forward and backward hemispheres are the same within experimental errors.

Forward-backward multiplicity correlations of target fragments in nucleus-emulsion collisions at a few hundred MeV/u

The forward-backward multiplicity and correlations of a target evaporated fragment （black track particle） and target recoiled proton （grey track particle） emitted from 150 A MeV 4He, 290 A MeV ^12C, 400 A MeV ^12C, 400 A MeV ^20Ne and 500 A MeV ^56Fe induced different types of nuclear emulsion target interactions are investigated. It is found that the forward and backward averaged multiplicity of a grey, black and heavily ionized track particle increases with the increase of the target size. The averaged multiplicity of a forward black track particle, backward black track particle, and backward grey track particle do not depend on the projectile size and energy, but the averaged multiplicity of a forward grey track particle increases with an increase of projectile size and energy. The backward grey track particle multiplicity distribution follows an exponential decay law and the decay constant decreases with an increase of target size. The backward-forward multiplicity correlations follow linear law which is independent of the projectile size and energy, and the saturation effect is observed in some heavy target data sets.

Multiplicity fluctuation analysis of target residues in nucleusemulsion collisions at a few hundred MeV/nucleon

Multiplicity fluctuation of the target evaporated fragments emitted in 290 MeV/u 12C-AgBr, 400 MeV/u 12C-AgBr, 400 MeV/u 20Ne-AgBr and 500 MeV/u 56Fe-AgBr interactions is investigated using the scaled factorial moment method in two-dimensional normal phase space and cumulative variable space, respectively. It is found that in normal phase space the scaled factorial moment （ln（Fq）） increases linearly with the increase of the divided number of phase space （lnM） for lower q-value and increases linearly with the increase of lnM, and then becomes saturated or decreased for a higher q-value. In cumulative variable space ln（Fq） decreases linearly with increase of lnM. This indicates that no evidence of non-statistical multiplicity fluctuation is observed in our data sets. So, any fluctuation indicated in the results of normal variable space analysis is totally caused by the non-uniformity of the single-particle density distribution.

Preliminary Study on Detecting the SARS-CoV Specific Target cDNA Fragments by Multiplex PCR

The multiplex polymerase chain reaction (PCR) technique was applied to detectthe SARS-CoV (severe acute respiratory syndrome-associated coronavirus) specific target cDNAfragments in the present study. The target cDNA fragments of SARS-CoV were synthesized artificiallyaccording to the genome sequence of SARS-CoV in GenBank submitted by The Chinese University of HongKong, and were used as simulated positive samples. Five primers recommended by World HealthOrganization (WHO) were used to amplify the fragments by single PCR and multiplex PCR. Three targetcDNA fragments (121, 182 and 302 bp), as well as the three different combinations of any two ofthese fragments, were amplified by single PCR. The combination of these three fragments wasamplified by multiplex PCR. The results indicated that the multiplex PCR technique could be appliedto detect the SARS-CoV specific target cDNA fragments successfully.

Intermittent type fluctuation of target fragments produced in ^(16)O-AgBr interactions at 4.5 AGeV/c

A study of intermittency of target associated fragments produced in the interactions of ^16O- AgBr at 4.5 AGeV/c with nuclear emulsion using the method of factorial moments, F4, has been performed. The dependence of the moments on the number of bins M is found to follow a power law behavior for the experimental data in terms of new scaled variable Х（Z） suggested by Bialas and Gazdzicki. The anomalous dimensions, dq, increase linearly with the order of moments, q. This observation indicates the association of multifractility with production mechanism of target associated fragments.

Evidence of self-affine multiplicity fluctuation of target residues in ^(84)Kr-AgBr interactions at 1.7 AGeV

Self-affine multiplicity scaling is investigated in the framework of a two-dimensional factorial moment methodology using the concept of the Hurst exponent （H）. Analyzing the experimental data of target evaporated fragments emitted in ^84Kr-AgBr interactions at 1.7 AGeV revealed that the best power law behavior is exhibited for H = 0.3 indicating a self-arlene multiplicity fluctuation pattern. A signal of multifractality is also observed from knowledge of the anomalous fractal dimension dq extracted from the intermittency exponent aq of the anisotropic phase space scenario.