4,297 research outputs found
Next-to-leading gluonic reggeons in the high-energy effective action
We study the next-to-leading gluon exchange in the high-energy scattering
that contributes to the amplitude to order up to logarithmic corrections.
Similar to the leading gluon exchange these contribution can be described in
terms of reggeon exchanges. There are several gluonic reggeons at the
next-to-leading level. Some of them transfer parity or gauge group
representation different from the leading gluonic reggeon. Unlike the leading
one they are sensitive to the helicity and transverse momenta of the scattering
partons. We extend the high-energy effective action and derive from the action
of gluodynamics the terms describing the next-to-leading reggeons and their
interaction in the multi-Regge approximation.Comment: 31 pages in LATEX, 4 eps figures, references adde
Geophysical data base
A general data-management system that provides a random-access capability for large amounts of data is described. The system operates on a CDC 6400 computer using a combination of magnetic tape and disk storage. A FORTRAN subroutine package is provided to simplify the maintenance and use of the data
Diffractive meson production from virtual photons with odd charge-parity exchange
We calculate the cross section of diffractive charge-parity C=+1 neutral
meson production in virtual photon proton collision at high energies. Due to
the opposite C-parities of photon and meson M (M = eta_C, pi^0, a_2) this
process probes the t-channel C=-1 odderon exchange which is described here as
noninteracting three-gluon exchange. Estimates for the cross section of the
inelastic diffractive process gamma^* p -> eta_C X_p are presented. The total
cross section of diffractive \eta_C meson photoproduction is found to be 47 pb.
The cross sections for the diffractive production of light mesons (pi^0, a_2)
in \gamma^* p collisions are of the same order if the photon virtuality Q^2 is
m^2_C.Comment: LaTeX, 19 pages, 8 ps-figs, epsfi
Symmetries of BFKL Equation
We discuss the algebraic structure of the spin chains related to high energy
scattering in QCD. We study the sl(2) Yangian symmetry and possible
generalizations to nonzero spin and anisotropy parameter.Comment: 16 pages, Late
Bioanalytical Development Of Charged Cyclodextrin Capillary Electrokinetic Chromatography And Microperfusion Sampling To Study Endogenous D-Serine And L-Glutamate Efflux In Brain
Thesis (Ph.D.) University of Alaska Fairbanks, 2009A multitude of studies have revealed specific biological mechanisms that contribute to D-amino acid action and regulation in the mammalian central nervous system. The remarkable increase in our understanding of D-amino acid function and distribution in mammals is in many ways a result of the development of sensitive enantioselective separation strategies that allow for quantification in real biological samples. In capillary electrokinetic chromatography (cEKC) the most powerful chiral resolving agents are anionic cyclodextrins (CDs), yet these have not previously been investigated for chiral bioanalysis of amino acids. The focus of this dissertation research was to investigate for the first time the feasibility of and application of anionic cyclodextrins as resolving agents in bioanalytical chiral separations of amino acids. This dissertation encompasses (1) the development of a new bioanalytical separation utilizing capillary electrophoresis laser induced fluorescence (CE-LIF) with sulfated-beta-cyclodextrin for analysis of D-serine (D-ser) and L-glutamate (L-glu) in mammalian brain, (2) the first synthesis and characterization of 6 members of a new family of single isomer sulfoalkyl cyclodextrins, (3) initial studies on chiral analysis of amino acids using single isomer sulfoalkyl CDs, and (4) development and application of a novel microperfusion sampling approach for acute brain slices and coupling of this method to the developed chiral CE-LIF for studying magnitude and timing of D-ser and L-glu efflux from acute hippocampus in response to modeled cerebral ischemia. The results of these studies demonstrate that (1) anionic CDs are powerful chiral selectors for amino acids and can be applied for sensitive bioanalysis of D-amino acids including D-ser, D-glu, and D-asp in brain samples; (2) single isomer sulfoalkyl CDs can be synthesized by regioselective reaction chemistry; (3) single isomer sulfoalkyl CDs are excellent resolving agents for amino acid analysis and may be valuable for bioanalytical chiral applications; and (4) microperfusion sampling coupled to CE-LIF can be used to analyze dynamic changes in the magnitude and timing of neurochemical efflux from single acute hippocampus slices exposed to modeled ischemia. Results of these latter studies suggest that D-ser and L-glu efflux occurs simultaneously in acute hippocampus with similar timing but differing magnitudes
A rocket ozonesonde for geophysical research and satellite intercomparison
The in-situ rocketsonde for ozone profile measurements developed and flown for geophysical research and satellite comparison is reviewed. The measurement principle involves the chemiluminescence caused by ambient ozone striking a detector and passive pumping as a means of sampling the atmosphere as the sonde descends through the atmosphere on a parachute. The sonde is flown on a meteorological sounding rocket, and flight data are telemetered via the standard meteorological GMD ground receiving system. The payload operation, sensor performance, and calibration procedures simulating flight conditions are described. An error analysis indicated an absolute accuracy of about 12 percent and a precision of about 8 percent. These are combined to give a measurement error of 14 percent
The gluon field of a fast moving nucleus and the effective langrangian for QCD at high energy
Starting from the effective lagrangian for QCD at high energy we calculate
the lowest perturbative contributions to the potential of a relativistic
nucleus and compare our results to those derived by Kovchegov (see Y.V.
Kovchegov, Phys. Rev. {\bf D55}, 5445 (1997)). The results differ already at
order g^3 which can be traced to the fact that the meaning of the underlying
gluon fields is different. (The effective gluon field we use is a gauge
invariant object.) Both approaches should therefore be seen as alternatives,
the relative merits of which have to be judged by their phenomenological
success.Comment: 13 pages, 4 figures. v2: eq. 18 corrected, modified discussion of the
relation between the standard and the effective lagrangian approac
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