1,545 research outputs found
Inclusive gluon production in the dipole approach: AGK cutting rules
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
The article is devoted to the reaction of the American press to such an important historical event as the founding of the Peopleâs 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 â the Communist Party of China (CCP) and the nationalist party Kuomintang â 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 â the âloss of Chinaâ 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 âlossâ, to level the image damage caused to the population by Washingtonâs 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
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
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 mesons produced
in nuclear reactions.Comment: 3 journal-style page
Odderon and seven Pomerons: QCD Reggeon field theory from JIMWLK evolution
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 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 - channel gluons. The eigenstates have
a natural interpretation in terms of the - channel exchanges. Studying the
single - channel gluon sector we find the eigenstates which include the
reggeized gluon and five other colored Reggeons. In the two ( - 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
limit are where is the intercept of the BFKL
Pomeron, but their coupling in perturbation theory is suppressed by at least
relative to the double BFKL Pomeron exchange. For the Pomeron
we find . 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
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
Inverse Eigenvalue Problems for Perturbed Spherical Schroedinger Operators
We investigate the eigenvalues of perturbed spherical Schr\"odinger operators
under the assumption that the perturbation satisfies . 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 near . Furthermore, we provide sets of spectral data
which uniquely determine .Comment: 14 page
Speed Meter As a Quantum Nondemolition Measuring Device for Force
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
Oscillation of linear ordinary differential equations: on a theorem by A. Grigoriev
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
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