Collective and fractal properties of pion jets in the four-velocity space at intermediate energies

Experimental results are presented for study of collective and fractal properties of soft pion jets in the space of relative four-dimensional velocities. Significant decreasing is obtained for mean square of second particle distances from jet axis for pion-proton interactions at initial energies $\sim 3$ GeV in comparison with hadron-nuclear collisions at close energies. The decreasing results in power dependence of distance variable on collision energy for range $\sim 2 - 4$ GeV. The observation allows us to estimate the low boundary of manifestation of color degree of freedom in pion jet production. Cluster dimension values were deduced for pion jets in various reactions. Fractional values of this dimension indicate on the manifestation of fractal-like properties by pion jets. Changing of mean kinetic energy of jet particles and fractal dimension with initial energy increasing is consistent with suggestion for presence of color degrees of freedom in pion jet production at intermediate energies.Comment: The conference "Physics of fundamental interactions". ITEP, Moscow, Russia. November 23 - 27, 200

On QCD Q2Q^2-evolution of Deuteron Structure Function F2D(xD,Q2)F_2^D(x_D,Q^2) for xD>1x_D>1

The deep-inelastic deuteron structure function (SF) $F_2^D(x_D,Q^2)$ in the covariant approach in light-cone variables is considered. The $x_D$ and $Q^2$-dependences of SF are calculated. The QCD analysis of generated data both for non-cumulative $x_D1$ ranges was performed. It was shown that $Q^2$-evolution of SF is valid for ranges $0.275<x_D<0.85$ and $1.1<x_D<1.4$ for the same value of QCD scale parameter ${\Lambda}$. It was found the $x_D$-dependence of SF for the ranges is essentially different.Comment: LaTeX, 10 pages, 2 Postscript figure

Enabling comparison of UrQMD with Geant4 hadronic models

Geant4 has an abundant set of physics models that handle the diverse interaction of particles with matter across a wide energy range. However, there are also many well established reaction codes currently used in the same fields where Geant4 is applied. One such code is the Ultra-relativistic Quantum Molecular Dynamics (UrQMD) model. In order to take advantage of the UrQMD code, we create a tool to enable comparisons among UrQMD and Geant4 hadronic models. This tool allows a user to process the output file of UrQMD through Geant4 toolkit, while at the same time, can choose among different Geant4 hadronic model generators. As an example, the UrQMD model is compared with the HARP-CDP experimental data and with the Binary and FRITIOF generators, in the framework of Geant4. It is shown that the UrQMD model can better reproduce charged pion production for p+Cu and Pb interactions at 3, 8 and 15 GeV/c, and is a good candidate for Geant4 hadronic models.Comment: 17 pages, 5 Figure

Energy Storage in a Hamiltonian System in Partial Contact with a Heat Bath

To understand the mechanism allowing for the long-term storage of excess energy in proteins, we study a Hamiltonian system consisting of several coupled pendula in partial contact with a heat bath. It is found that energy storage is possible when the motion of each pendulum switches between oscillatory (vibrational) and rotational (phase-slip) modes. The storage time increases almost exponentially to the square root of the injected energy. The relevance of our mechanism to protein motors is discussed.Comment: 8 pages, 4 figures, to appear in J.Phys.Soc.Jp

Jet Energy Density in Hadron-Hadron Collisions at High Energies

The average particle multiplicity density dN/deta is the dynamical quantity which reflects some regularities of particle production in low-pT range. The quantity is an important ingredient of z-scaling. Experimental results on charged particle density are available for pp, pA and AA collisions while experimental properties of the jet density are still an open question. The goal of this work is to find the variable which will reflect the main features of the jet production in low transverse energy range and play the role of the scale factor for the scaling function psi(z) and variable z in data z-presentation. The appropriate candidate is the variable we called "scaled jet energy density". Scaled jet energy density is the probability to have a jet with defined ET in defined xT and pseudorapidity regions. The PYTHIA6.2 Monte Carlo generator is used for calculation of scaled jet energy density in proton-proton collisions over a high energy range (sqrt s = 200-14000 GeV) and at eta = 0. The properties of the new variable are discussed and sensitivity to "physical scenarios" applied in the standard Monte Carlo generator is noted. The results of scaled jet energy density at LHC energies are presented and compared with predictions based on z-scaling.Comment: 11 pages, LaTeX, 8 figures, Presented at the XVII International Baldin Seminar on High Energy Physics Problems "Relativistic Nuclear Physics & Quantum Chromodynamics", Dubna, Russia, September 27 - October 2, 200

Search for associated Higgs boson production using like charge dilepton events in p(p)over-bar collisions at root s=1.96 TeV

We present a search for associated Higgs boson production in the process p (p) over bar -> W/ZH -> l(+/-)l'(+/-) + X in ee, e mu, and mu mu final states. The search is based on data collected by the D0 experiment at the Fermilab Tevatron Collider at root s = 1.96 TeV corresponding to 5.3 fb(-1) of integrated luminosity. We require two isolated leptons (electrons or muons) with the same electric charge and additional kinematic requirements. No significant excess above background is observed, and we set 95% C. L. observed (expected) upper limits on ratio of the production cross section to the standard model prediction of 6.4 (7.3) for a Higgs boson mass of 165 GeV and 13.5 (19.8) for a mass of 115 GeV

Feeding behavior of \u3ci\u3eAphis glycines\u3c/i\u3e (Hemiptera: Aphididae) on soybeans exhibiting antibiosis, antixenosis, and tolerance resistance

Aphis glycines Matsumura (Hemiptera: Aphididae) is a serious pest of soybean in North America. Plant resistance is a valuable tool for the management of this pest, and a better understanding of the interactions between aphid and soybeans expressing varying levels and different categories of resistance can assist in the development of aphid resistant or tolerant genotypes. The electrical penetration graph (EPG) technique was used to evaluate the feeding behavior of A. glycines (biotype 1) on 4 soybean genotypes: (1) ‘Dowling’ (contains Rag1 gene and exhibits antibiosis); (2) PI 200538 (contains Rag2 gene and exhibits antixenosis); (3) KS4202 (exhibits tolerance); and (4) ‘SD76RR’ (susceptible to aphid). Aphids spent shorter periods in the sieve element phase on ‘Dowling’ and exhibited a greater number of pathway phases, non-probing events, and a longer time in nonprobing events in PI 200538 and ‘Dowling.’ For ‘SD76RR’ and KS4202, aphids demonstrated more sustained phloem ingestion, spent shorter time in non-probing events, and exhibited fewer pathway phases and potential drops. These results indicate that resistance factors are present in the phloem of ‘Dowling.’ For PI 200538, it is suggested that antixenotic factors are involved in resistance to A. glycines. Because KS4202 is tolerant to biotype 1 of A. glycines, the suitability of this genotype was expected already. This study provides important data that contribute to the understanding of how soybean aphids (biotype 1) feed on soybean genotypes with various aphid resistant genes and categories. In addition to assisting in the distinction between resistance categories, these results are useful in soybean breeding programs focusing on developing genotypes with greater resistance to insects. Aphis glycines Matsumura (Hemiptera: Aphididae) é uma das principais pragas da cultura da soja na América do Norte. Dentre as técnicas de manejo da praga, a resistência de plantas a insetos se destaca como uma ferramenta valiosa. Assim, uma melhor compreensão sobre as interações entre o afídeo e plantas de soja que expressam variáveis níveis e diferentes categorias de resistência, pode auxiliar no desenvolvimento de genótipos resistentes ao inseto. A técnica de EPG foi utilizada para avaliar o comportamento alimentar de A. glycines (biótipo 1) em 4 genótipos de soja: (1) ‘Dowling’ (contém gene Rag1 e expressa antibiose); (2) PI 200538 (contém gene Rag2 e expressa antixenose); (3) KS4202 (expressa tolerância); e (4) ‘SD76RR’ (suscetível ao afídeo). Os afídeos demonstraram curtos períodos de alimentação na fase de seiva em ‘Dowling’ e exibiram uma grande quantidade de fases de caminhamento estiletar, número de períodos de não-prova e longos período de não-prova em PI 200538 e ‘Dowling.’ Para ‘SD76RR’ e KS4202, os afídeos mostraram um maior período de alimentação em vasos do floema, apresentaram curtos períodos de não-prova e exibiram poucas fases de caminhamento estiletar, além de menor número de quedas de potencial. Os resultados indicam que fatores de resistência estão presentes nos vasos floemáticos de ‘Dowling.’ Para PI200538, sugere-se que fatores antixenóticos estão envolvidos na resistência a A. glycines. Uma vez que KS4202 expressa tolerância ao biótipo 1 de A. glycines, a adequabilidade deste genótipo como fonte de alimento para o inseto já era esperada. Este estudo fornece importantes dados que contribuem para um melhor entendimento de como o pulgão-da-soja (biótipo 1) se alimentam de plantas de soja portadoras de diferentes genes e categorias de resistência. Além de auxiliar na distinção entre as categorias de resistência, esses resultados podem ser úteis em programas de melhoramento de soja, com intuito de selecionar genótipos mais resistentes a insetos

Collective behaviour of partons could be a source of energetic hadrons

We discuss the idea that collective behaviour of the quarks/partons, which has been intensely discussed for the last 40 years in relativistic hadron-nuclear and nuclear-nuclear interactions and confirmed by new data coming from the ultrarelativistic heavy ion collisions, can lead to energetic particle production. Created from hadronization of the quark/parton (or quarks/partons), energetic particles could get the energy of grouped partons from coherent interactions. Therefore, we think that in the centre of some massive stars, a medium with high density, close to Quantum Chromodynamic one could be a source of the super high-energy cosmic rays.Comment: 8 pages, 8 figure

Feeding behavior of \u3ci\u3eAphis glycines\u3c/i\u3e (Hemiptera: Aphididae) on soybeans exhibiting antibiosis, antixenosis, and tolerance resistance

Aphis glycines Matsumura (Hemiptera: Aphididae) is a serious pest of soybean in North America. Plant resistance is a valuable tool for the management of this pest, and a better understanding of the interactions between aphid and soybeans expressing varying levels and different categories of resistance can assist in the development of aphid resistant or tolerant genotypes. The electrical penetration graph (EPG) technique was used to evaluate the feeding behavior of A. glycines (biotype 1) on 4 soybean genotypes: (1) ‘Dowling’ (contains Rag1 gene and exhibits antibiosis); (2) PI 200538 (contains Rag2 gene and exhibits antixenosis); (3) KS4202 (exhibits tolerance); and (4) ‘SD76RR’ (susceptible to aphid). Aphids spent shorter periods in the sieve element phase on ‘Dowling’ and exhibited a greater number of pathway phases, non-probing events, and a longer time in nonprobing events in PI 200538 and ‘Dowling.’ For ‘SD76RR’ and KS4202, aphids demonstrated more sustained phloem ingestion, spent shorter time in non-probing events, and exhibited fewer pathway phases and potential drops. These results indicate that resistance factors are present in the phloem of ‘Dowling.’ For PI 200538, it is suggested that antixenotic factors are involved in resistance to A. glycines. Because KS4202 is tolerant to biotype 1 of A. glycines, the suitability of this genotype was expected already. This study provides important data that contribute to the understanding of how soybean aphids (biotype 1) feed on soybean genotypes with various aphid resistant genes and categories. In addition to assisting in the distinction between resistance categories, these results are useful in soybean breeding programs focusing on developing genotypes with greater resistance to insects. Aphis glycines Matsumura (Hemiptera: Aphididae) é uma das principais pragas da cultura da soja na América do Norte. Dentre as técnicas de manejo da praga, a resistência de plantas a insetos se destaca como uma ferramenta valiosa. Assim, uma melhor compreensão sobre as interações entre o afídeo e plantas de soja que expressam variáveis níveis e diferentes categorias de resistência, pode auxiliar no desenvolvimento de genótipos resistentes ao inseto. A técnica de EPG foi utilizada para avaliar o comportamento alimentar de A. glycines (biótipo 1) em 4 genótipos de soja: (1) ‘Dowling’ (contém gene Rag1 e expressa antibiose); (2) PI 200538 (contém gene Rag2 e expressa antixenose); (3) KS4202 (expressa tolerância); e (4) ‘SD76RR’ (suscetível ao afídeo). Os afídeos demonstraram curtos períodos de alimentação na fase de seiva em ‘Dowling’ e exibiram uma grande quantidade de fases de caminhamento estiletar, número de períodos de não-prova e longos período de não-prova em PI 200538 e ‘Dowling.’ Para ‘SD76RR’ e KS4202, os afídeos mostraram um maior período de alimentação em vasos do floema, apresentaram curtos períodos de não-prova e exibiram poucas fases de caminhamento estiletar, além de menor número de quedas de potencial. Os resultados indicam que fatores de resistência estão presentes nos vasos floemáticos de ‘Dowling.’ Para PI200538, sugere-se que fatores antixenóticos estão envolvidos na resistência a A. glycines. Uma vez que KS4202 expressa tolerância ao biótipo 1 de A. glycines, a adequabilidade deste genótipo como fonte de alimento para o inseto já era esperada. Este estudo fornece importantes dados que contribuem para um melhor entendimento de como o pulgão-da-soja (biótipo 1) se alimentam de plantas de soja portadoras de diferentes genes e categorias de resistência. Além de auxiliar na distinção entre as categorias de resistência, esses resultados podem ser úteis em programas de melhoramento de soja, com intuito de selecionar genótipos mais resistentes a insetos