The Two-Component Non-Perturbative Pomeron and the G-Universality

In this communication we present a generalization of the Donnachie-Landshoff model inspired by the recent discovery of a 2-component Pomeron in LLA-QCD by Bartels, Lipatov and Vacca. In particular, we explore a new property, not present in the usual Regge theory - the G-Universality - which signifies the independence of one of the Pomeron components on the nature of the initial and final hadrons. The best description of all the forward hadron-hadron, gamma- gamma and gamma-proton data is obtained when G-universailty is imposed. Moreover, the maximal (ln)**2 behaviour of the hadron amplitude, first established by Heisenberg, is clearly favoured by the data.Comment: 5 pages, 2 tables, talk at the International Workshop on Diffraction in High-Energy Physics "Diffraction 2000", Cetraro, Italy, September 2-7, 200

Phenomenological analysis of the double pion production in nucleon-nucleon collisions up to 2.2 GeV

With an effective Lagrangian approach, we analyze several NN \to NN\pi\pi channels by including various resonances with mass up to 1.72 GeV. For the channels with the pion pair of isospin zero, we confirm the dominance of N*(1440)\to N\sigma in the near threshold region. At higher energies and for channels with the final pion pair of isospin one, we find large contributions from N*(1440)\to \Delta\pi, double-Delta, \Delta(1600) \to N*(1440)\pi, \Delta(1600) \to \Delta\pi and \Delta(1620) \to \Delta\pi. There are also sizeable contributions from \Delta \to \Delta\pi, \Delta \to N\pi, N \to \Delta\pi and nucleon pole at energies close to the threshold. We well reproduce the total cross sections up to beam energies of 2.2 GeV except for the pp\to pp\pi^0\pi^0 channel at energies around 1.1 GeV and our results agree with the existing data of differential cross sections of pp \to pp\pi^+\pi^-, pp \to nn\pi^+\pi^+ and pp \to pp\pi^0\pi^0 which are measured at CELSIUS and COSY.Comment: 36 pages, 18 figure

Hadron Diffractive Processes: the Structure of Soft Pomeron and Colour Screening

On the basis of the experimental data on diffractive processes in $\pi p$, $pp$ and $p \bar p$ collisions at intermediate, moderately high and high energies, we restore the scattering amplitude related to the $t$-channel exchange by vacuum quantum numbers by taking account of the diffractive $s$-channel rescatterings. At intermediate and moderately high energies, the $t$-channel exchange amplitude turns, with a good accuracy, into an effective pomeron which renders the results of the additive quark model. At superhigh energies the scattering amplitude provides a Froissart-type behaviour, with an asymptotic universality of cross sections such as $\sigma^{tot}_{\pi p}/\sigma^{tot}_{pp} \to 1$ at $s \to \infty$. The quark structure of hadrons being taken into account at the level of constituent quarks, the cross sections of pion and proton (antiproton) in the impact parameter space of quarks, $\sigma_{\pi}(\vec {r}_{1\perp},\vec {r}_{2\perp};s)$ and $\sigma_p(\vec {r}_{1\perp},\vec {r}_{2\perp},\vec {r}_{3\perp};s)$, are found as functions of $s$. These cross sections implicate the phenomenon of colour screening: they tend to zero at $|\vec r_{i\perp}-\vec r_{k\perp}| \to 0$. The effective colour screening radius for pion (proton) is found for different $s$. The predictions for the diffractive cross sections at superhigh energies are presented.Comment: LaTeX, epsfig.st

Державна територія та територіальна цілісність: структурно-функціональний аналіз морфології понять

Problem setting. In most states, the territorial issues were accompanied by the establishment of a sovereign power, the inviolability of borders, the preservation of the independence of the state, the search for a new model of national identity. As a result, territorial integrity has gained the appropriate level of institutionalization and legitimization at the international and national levels, thus becoming one of the most pressing problems for modern humanities.The basis for understanding the territorial integrity of the state is the study of Hajd, Ch. (2005). The territorial integrity of the state scientist understood as its unity and indivisibility, while inviolability – as the preservation of the integrity of the territory, protection from encroachments by other states or other political forces. In this respect, the territorial integrity and inviolability of the territory are considered by the author as a whole and partial, on the basis of which the inviolability acts as a structural component and a necessary condition for the territorial integrity of the state.The purpose of the paper is to conduct a conceptual analysis of the concept of state territory and territorial integrity in the context of modern political science. The objectives of the paper are to find out the essence of the state territory, to specify the main theories of its research, to systematize the main research approaches to the identification of the content of territorial integrity and the tools for its protection within the framework of domestic and Western political science.The paper main body. The concept of Cassese, A. (2007) is of significant methodological value within the research. The territorial integrity of the state he understood as “an element of state unity characterizing the immutability of state borders, territorial integrity and inviolability of the territory of the state historically formed and people living in a certain territory”. On this basis, territorial integrity is the basis of strengthening the constitutional system, which in no case may contradict the principle of the right of people to self-determination. Within this research logic, an important role in implementing the mechanism of ensuring the territorial integrity of the state is given to judicial instruments for resolving territorial disputes within a single constitutional space.The scientific approach by Fukujama, F. (2004) is analyzed. The scientist makes a methodological attempt to carry out a detailed analysis of the notions of “state unity” and “territorial integrity”.Within the bounds of political analysis, the concept of Eide, A. (2015) is of great conceptual value. He defines the notions of “territorial integrity”, “state integrity” and “territorial inviolability”. The concept of Jacobson, J. (2014) in this context is also of great importance. The author reveals the essence of territorial integrity in the context of the implementation of the principle of inviolability of borders, which is an important condition for the solution of issues of protection of state borders, which are essential for the provision of international security throughout the world.Conclusions of the research. Thus, our analysis made it possible to find out the essence of the notions of “state border”, “territorial integrity”, “territorial integrity” by systematizing the main research approaches that were formed in the context of world and national scientific thought. On this basis, the structural and functional content of the state territory is clarified, including the determination of its composition, history of formation, morphology, location and characteristics of the boundaries. The economic and political peculiarities of the development of the state territory are presented. The relationship between the structure of the state territory and the territorial structure of the economy, the content of territorial disputes and claims between the states, as well as the nature of the corresponding territorial-ethnic conflicts, which leads to a violation of its integrity, are disclosed.The notions of territorial integrity, which refers to unity and indivisibility, and territorial inviolability, which characterizes the preservation of the integrity of the territory, protection from encroachments by other states or other political forces, are delimited.Territorial integrity and territorial inviolability are considered as integral and partial, on the basis of which the inviolability acts as a structural component and a necessary condition for the territorial integrity of the state. It is this aspect that is least developed within the framework of modern political science, which thus forms the methodological prospects for further study of this problem.Раскрыта сущность государственной территории, конкретизированы основные теории ее исследования, в частности концепции А. Кейсеса, Ф. Фукуямы, А. Эйде, Ж. Якобсона, А. Эртеля. Систематизированы основные исследовательские подходы к идентификации содержания территориальной целостности и инструментов ее защиты; которые были сформированы в пределах мировой научной мысли. Уточняется структурное и функциональное содержание территории государства, определяется ее структурный состав, освещаются исторические аспекты ее образования, морфология, место нахождения и характеристика границ. Освещены экономические и политические особенности развития государственной территории. Установлена взаимосвязь между структурой государственной территории и территориальной структурой экономики, содержанием территориальных споров и претензий между государствами, а также характером соответствующих территориально-этнических конфликтов, что приводит к их целостности. Установлена сущность понятий «государственная граница», «территориальная целостность», раскрыто их структурно-функциональное содержание, состав. История формирования, морфология, место размещения и характеристика границ; представлены экономические и политические особенности их развития.Разграничены понятия территориальной целостности, под которой понимается единство и неделимость, и территориальной неприкосновенности, что характеризует сохранение целостности территории, защиту от посягательств со стороны других государств или политических сил. Территориальная целостность и неприкосновенность территории рассматриваются как целое и частное, на основании чего неприкосновенность выступает структурной составляющей и необходимым условием территориальной целостности государства.Проанализирована взаимосвязь между структурой государственной территории и территориальной структурой хозяйствования, определено содержание территориальных споров и претензий между государствами, а также проведена характеристика природы соответствующих территориально-этнических конфликтов, которые приводят к нарушению ее целостности.З’ясовується сутність державної території, конкретизовано основні теорії її дослідження, зокрема, концепції А. Кейсеса, Ф. Фукуями, А. Ейде, Ж. Якобсона, А. Ертеля. Систематизовано основні дослідницькі підходи до ідентифікації змісту територіальної цілісності та інструментів її захисту, які були сформовані в межах світової наукової думки. Уточнюється структурний і функціональний зміст території держави, визначається її структурний склад, висвітлюються історичні аспекти її утворення, морфологія, місце знаходження і характеристики кордонів. Висвітлено економічні і політичні особливості розвитку державної території. Встановлено взаємозв’язок між структурою державної території і територіальною структурою економіки, змістом територіальних суперечок і претензій між державами, а також характером відповідних територіально-етнічних конфліктів, що призводить до порушення її цілісності. З’ясовано сутність понять «державний кордон», «територіальна цілісність», розкрито їх структурно-функціональний зміст, склад, історію формування, морфологію, місце розташування та характеристики кордонів; наведено економічні й політичні особливості її розвитку.Розмежовано поняття територіальної цілісності, під якою розуміється єдність та неподільність, та територіальної недоторканості, що характеризує збереження цілісності території, захист від посягань з боку інших держав або інших політичних сил. Територіальна цілісність та недоторканість території розглядаються як ціле та часткове, на підставі чого недоторканість виступає структурною складовою та необхідною умовою територіальної цілісності держави. Проаналізовано взаємозв’язок між структурою державної території та територіальною структурою господарювання, визначено зміст територіальних суперечок і претензій між державами, а також охарактеризовано природу відповідних територіально-етнічних конфліктів, які призводять до порушення її цілісності

Proton-nucleus scattering and cross section fluctuations at RHIC and LHC

We consider high-energy proton-heavy nucleus scattering within the framework of the Glauber-Gribov approximation and taking into account cross section fluctuations. Fixing parameters of the model for cross section fluctuations by the available data, we make predictions for the total, elastic and coherent diffractive dissociation proton-nucleus cross sections for the RHIC and LHC energy range. We predict a strong change of the A-dependence of diffraction dissociation from A^{0.42} at RHIC energies to A^{0.27} at LHC energies. Based on the obtained results, we discuss the approach of the interactions to the black body (unitarity) limit. We estimate the electromagnetic contribution to coherent pA diffraction and find that it dominates the coherent diffractive cross section on heavy nuclear targets in the RHIC and LHC kinematics.Comment: 18 pages, LaTeX, 1 table, 4 figures. This is the final version published in Phys. Lett. B 633 (2006) 245, with recent corrections published as Erratum in Phys. Lett. B 663 (2008) 456. The Erratum concerns Section 5 of the paper: we corrected the Lorentz factor for the calculation of the e.m. contribution and modified Fig.

D^+_s -> pi^+ pi^+ pi^- decay: the 1^3P_0 s anti-s component in scalar-isoscalar mesons

On the basis of data on the decay D^+_s -> pi^+ pi^+ pi^-, which goes dominantly via the transition D_s -> pi^+ s anti-s, we evaluate the 1^3P_0 s anti-s components in the scalar-isoscalar resonances f0(980), f0(1300), f0(1500) and broad state f0(1200-1600)$. The data point to a large s anti-s component in the f0(980): 40% < s anti-s < 70%. Nearly 30% of the 1^3P_0 s anti-s component flows to the mass region 1300-1500 MeV being shared by f0(1300), f0(1500) and broad state f0(1200-1600): the interference of these states results in a peak near 1400 MeV with the width around 200 MeV.Comment: 17 pages, 4 figures, epsfi

Pomeron in diffractive processes γ∗(Q2)p→ρ0p\gamma^*(Q^2)p\to\rho^0 p and γ∗(Q2)p→γ∗(Q2)p\gamma^*(Q^2)p\to\gamma^*(Q^2) p at large Q^2: the onset of pQCD

We study the reactions $\gamma^*(Q^2)p\to\rho^0 p$ and $\gamma^*(Q^2)p\to\gamma^*(Q^2) p$ at large Q^2 and $W^2/Q^2$ and small momentum transfer, $\kappa^2_\perp$, to the nucleon where the pomeron exchange dominates. At large Q^2 the virtual photon selects a hard $q\bar q$ pair, thus selecting the hard pomeron component (the BFKL pomeron). The amplitudes for both transverse and longitudinal polarizations of the initial photon and outgoing $\rho$-meson (photon) are calculated in the framework of the BFKL pomeron exchange. Our calculations show that one cannot expect the early onset of the pure perturbative regime in the discussed diffractive processes: the small interquark distances, $\rho_{q\bar q} <0.2$ fm, start to dominate not earlier than at $Q^2 \simeq 100 GeV^2, W^2/Q^2 \simeq 10^7$ in $\gamma^*(Q^2)p\to\rho^0 p$ and $Q^2 \simeq 50 GeV^2, W^2/Q^2 \simeq 10^6$ in $\gamma^*(Q^2)p\to\gamma^*(Q^2) p$.Comment: 20 pages, LaTeX, epsfig.st

Theoretical study of the N N --> N N pi pi reaction

We have developed a model for the N N --> N N pi pi reaction and evaluated cross sections for the different charged channels. The low energy part of those channels where the pions can be in an isospin zero state is dominated by N* excitation, driven by an isoscalar source recently found experimentally, followed by the decay N* --> N (pi pi, T=0, s-wave). At higher energies, and in channels where the pions are not in T=0, Delta excitation mechanisms become relevant. A rough agreement with the experimental data is obtained in most channels. Repercussions of the present findings for the ABC effect and the p p --> p p pi0 reaction close to threshold are also suggested.Comment: 22 pages, 12 postscripts figures, revised: a more general N* N pi pi Lagrangian is considered, to be published in Nucl. Phys.