1,565 research outputs found

    Inclusive gluon production in the dipole approach: AGK cutting rules

    Full text link
    We consider single gluon production in the dipole model and reproduce the result of Kovchegov and Tuchin for the adjoint (gluonic) dipole structure of the inclusive cross section. We show the validity of the adjoint dipole structure to any order of evolution deriving and solving the non-linear evolution for the non-diagonal cross section of a dipole scattering off the target. The form of the solution to this equation restores the dipole interpretation for non-diagonal cross sections, that appear in gluon production. Using this formalism, we analyse the single inclusive production cross section in terms of the contributions of different multiplicities, and we derive the Abramovskii-Gribov-Kancheli(AGK) cutting rules for two Pomeron exchange. The cutting rules, which were found in this formalism, fully reproduce the original AGK rules for the total cross section. However, for the case of gluon production, the AGK rules are violated already for one gluon emission from the vertex.Comment: 32 pages, 16 figure

    Proclamation of the PRC: Reaction of the American Press

    Get PDF
    The article is devoted to the reaction of the American press to such an important historical event as the founding of the People’s Republic of China. The emergence of a new communist state in the East was a great shock and blow to the foreign policy ambitions of the United States, which developed in the logic of a global confrontation with the Soviet Union. China, rich in resources since the end of the 19th century, has been the scene of a constant clash of interests of various states, as a result, on the eve and, especially, after World War II, the two main political forces operating in this territory — the Communist Party of China (CCP) and the nationalist party Kuomintang — found themselves powerful patrons in the form of the USSR and the USA. The topic of the reaction of the American press to the actual failure or, as he later said, was dubbed by numerous experts and publicists who wrote about China — the “loss of China” is an interesting marker of how socio-political thought developed in the American media. American journalists are trying to predict the political consequences of the “loss”, to level the image damage caused to the population by Washington’s foreign policy, to convey the facts and at the same time assess the situation in the region. The study of US press articles will make it possible to better understand the development of American ideas about China and its place in the new paradigm of international relations, to better explore the level of media awareness of this region and the impact that ideas and assessments broadcast by journalists had on society, as well as generally to better understand the initial reaction of American society to the founding of the PRC. Many of the ideas formed at that time remain today an important component of the discursive practices of US public and political life, especially taking into account the complex relations between modern China and the United States

    Formation of "Lightnings" in a Neutron Star Magnetosphere and the Nature of RRATs

    Full text link
    The connection between the radio emission from "lightnings" produced by the absorption of high-energy photons from the cosmic gamma-ray background in a neutron star magnetosphere and radio bursts from rotating radio transients (RRATs) is investigated. The lightning length reaches 1000 km; the lightning radius is 100 m and is comparable to the polar cap radius. If a closed magnetosphere is filled with a dense plasma, then lightnings are efficiently formed only in the region of open magnetic field lines. For the radio emission from a separate lightning to be observed, the polar cap of the neutron star must be directed toward the observer and, at the same time, the lightning must be formed. The maximum burst rate is related to the time of the plasma outflow from the polar cap region. The typical interval between two consecutive bursts is ~100 s. The width of a single radio burst can be determined both by the width of the emission cone formed by the lightning emitting regions at some height above the neutron star surface and by a finite lightning lifetime. The width of the phase distribution for radio bursts from RRATs, along with the integrated pulse width, is determined by the width of the bundle of open magnetic field lines at the formation height of the radio emission. The results obtained are consistent with the currently available data and are indicative of a close connection between RRATs, intermittent pulsars, and extreme nullers.Comment: 24 pages, no figures, references update

    Color mixing in high-energy hadron collisions

    Get PDF
    The color mixing of mesons propagating in a nucleus is studied with the help of a color-octet Pomeron partner present in the two-gluon model of the Pomeron. For a simple model with four meson-nucleon channels, color mixings are found to be absent for pointlike mesons and very small for small mesons. These results seem to validate the absorption model with two independent color components used in recent analyses of the nuclear absorption of J/ψJ/\psi mesons produced in nuclear reactions.Comment: 3 journal-style page

    Odderon and seven Pomerons: QCD Reggeon field theory from JIMWLK evolution

    Full text link
    We reinterpret the JIMWLK/KLWMIJ evolution equation as the QCD Reggeon field theory (RFT). The basic "quantum Reggeon field" in this theory is the unitary matrix RR which represents the single gluon scattering matrix. We discuss the peculiarities of the Hilbert space on which the RFT Hamiltonian acts. We develop a perturbative expansion in the RFT framework, and find several eigenstates of the zeroth order Hamiltonian. The zeroth order of this perturbation preserves the number of ss - channel gluons. The eigenstates have a natural interpretation in terms of the tt - channel exchanges. Studying the single ss - channel gluon sector we find the eigenstates which include the reggeized gluon and five other colored Reggeons. In the two (ss - channel) gluon sector we study only singlet color exchanges. We find five charge conjugation even states. The bound state of two reggeized gluons is the standard BFKL Pomeron. The intercepts of the other Pomerons in the large NN limit are 1+ωP=1+2ω1+\omega_P=1+2\omega where 1+ω1+\omega is the intercept of the BFKL Pomeron, but their coupling in perturbation theory is suppressed by at least 1/N21/N^2 relative to the double BFKL Pomeron exchange. For the [27,27][27,27] Pomeron we find ω[27,27]=2ω+O(1/N)>2ω\omega_{[27,27]}=2\omega+O(1/N)>2\omega. We also find three charge conjugation odd exchanges, one of which is the unit intercept Bartels-Lipatov-Vacca Odderon, while another one has an interecept greater than unity. We explain in what sense our calculation goes beyond the standard BFKL/BKP calculation. We make additional comments and discuss open questions in our approach.Comment: 58 pages, 4 figures, Extended version. To appear in JHE

    High energy scattering in 2+1 QCD

    Full text link
    High energy scattering in 2+1 QCD is studied using the recent approach of Verlinde and Verlinde. We calculate the color singlet part of the quark-quark scattering exactly within this approach, and discuss some physical implication of this result. We also demonstrate, by two independent methods, that reggeization fails for the color singlet channel. We briefly comment on the problem in 3+1 QCD.Comment: 20 pages, references adde

    Speed Meter As a Quantum Nondemolition Measuring Device for Force

    Get PDF
    Quantum noise is an important issue for advanced LIGO. Although it is in principle possible to beat the Standard Quantum Limit (SQL), no practical recipe has been found yet. This paper dicusses quantum noise in the context of speedmeter-a devise monitoring the speed of the testmass. The scheme proposed to overcome SQL in this case might be more practical than the methods based on monitoring position of the testmass.Comment: 7 pages of RevTex, 1 postscript figur

    Inverse Eigenvalue Problems for Perturbed Spherical Schroedinger Operators

    Full text link
    We investigate the eigenvalues of perturbed spherical Schr\"odinger operators under the assumption that the perturbation q(x)q(x) satisfies xq(x)∈L1(0,1)x q(x) \in L^1(0,1). We show that the square roots of eigenvalues are given by the square roots of the unperturbed eigenvalues up to an decaying error depending on the behavior of q(x)q(x) near x=0x=0. Furthermore, we provide sets of spectral data which uniquely determine q(x)q(x).Comment: 14 page

    Oscillation of linear ordinary differential equations: on a theorem by A. Grigoriev

    Full text link
    We give a simplified proof and an improvement of a recent theorem by A. Grigoriev, placing an upper bound for the number of roots of linear combinations of solutions to systems of linear equations with polynomial or rational coefficients.Comment: 16 page
    • 

    corecore