1,671 research outputs found
Techniques for QCD calculations by numerical integration
Calculations of observables in quantum chromodynamics are typically performed
using a method that combines numerical integrations over the momenta of final
state particles with analytical integrations over the momenta of virtual
particles. I describe the most important steps of a method for performing all
of the integrations numerically.Comment: 36 pages with 16 postscript figure
Partons and Jets at the LHC
I review some issues related to short distance QCD and its relation to the
experimental program of the Large Hadron Collider (LHC) now under construction
in Geneva.Comment: Talk at the conference QCD2002 at IIT Kanpur, India, November 2002.
Ten pages with 12 figure
Identifying Relevant Socio-Theoretic Foundations for Supporting Multi-Issue IT Cloudsourcing Negotiations
Service level agreement (SLA) negotiations involving cloud-based information technology (IT) service providers and customers are now commonplace. Although historical research on negotiation has often relied on economic foundations, the important nature of IT service levels to organizationsâĂĂŽ operational effectiveness suggests that negotiation complexities in the context of cloud-based outsourcing (or cloudsourcing) cannot be well understood by relying on economic perspectives alone. To that end, this paper reports on experiments designed to determine the relevance of competing sociotheoretic frameworks as they pertain to IT cloudsourcing negotiations. Contributions include a rigorous examination of hypotheses derived from social exchange theory, equity theory, learning theory, and the winâĂĂŹwin theories of negotiation. Additional contributions include the development of methodological constructs (using the Euclidean geometry) that reflect the complex nature of IT cloudsourcing SLAs, i.e., that they are composed of numerous service category contract clauses where negotiation tradeoffs within a service category as well as across service categories are possible. We find strong support for the relevance of the social exchange theory to IT cloudsourcing negotiations, as well as moderate support for the win-win theories of negotiation. Our conclusions provide clear directions for extending our work into the realm of negotiation support systems, and we rely on our findings to conjecture that IT cloudsourcing negotiation is a unique context for sociotheoretic negotiation research due to the inherent importance of information technologies to organizationsâĂĂŽ operational effectiveness
Liquid-liquid coexistence in the phase diagram of a fluid confined in fractal porous materials
Multicanonical ensemble sampling simulations have been performed to calculate
the phase diagram of a Lennard-Jones fluid embedded in a fractal random matrix
generated through diffusion limited cluster aggregation. The study of the
system at increasing size and constant porosity shows that the results are
independent from the matrix realization but not from the size effects. A
gas-liquid transition shifted with respect to bulk is found. On growing the
size of the system on the high density side of the gas-liquid coexistence curve
it appears a second coexistence region between two liquid phases. These two
phases are characterized by a different behaviour of the local density inside
the interconnected porous structure at the same temperature and chemical
potential.Comment: 5 pages, 4 figures. To be published in Europhys. Letter
Heavy Quark Production and PDF's Subgroup Report
We present a status report of a variety of projects related to heavy quark
production and parton distributions for the Tevatron Run II.Comment: Latex. 8 pages, 7 eps figures. Contribution to the Physics at Run II
Workshops: QCD and Weak Boson Physic
Variational formulation of ideal fluid flows according to gauge principle
On the basis of the gauge principle of field theory, a new variational
formulation is presented for flows of an ideal fluid. The fluid is defined
thermodynamically by mass density and entropy density, and its flow fields are
characterized by symmetries of translation and rotation. The rotational
transformations are regarded as gauge transformations as well as the
translational ones. In addition to the Lagrangians representing the translation
symmetry, a structure of rotation symmetry is equipped with a Lagrangian
including the vorticity and a vector potential bilinearly. Euler's
equation of motion is derived from variations according to the action
principle. In addition, the equations of continuity and entropy are derived
from the variations. Equations of conserved currents are deduced as the Noether
theorem in the space of Lagrangian coordinate \ba. Without , the
action principle results in the Clebsch solution with vanishing helicity. The
Lagrangian yields non-vanishing vorticity and provides a source
term of non-vanishing helicity. The vorticity equation is derived as an
equation of the gauge field, and the characterizes topology of the
field. The present formulation is comprehensive and provides a consistent basis
for a unique transformation between the Lagrangian \ba space and the Eulerian
\bx space. In contrast, with translation symmetry alone, there is an
arbitrariness in the ransformation between these spaces.Comment: 34 pages, Fluid Dynamics Research (2008), accepted on 1st Dec. 200
Successive Combination Jet Algorithm For Hadron Collisions
Jet finding algorithms, as they are used in and hadron collisions,
are reviewed and compared. It is suggested that a successive combination style
algorithm, similar to that used in physics, might be useful also in
hadron collisions, where cone style algorithms have been used previously.Comment: 18 pages plus four uuencoded postscript figures, REVTEX 3.0,
CERN-TH.6860/9
Diffractive jet production in a simple model with applications to HERA
In diffractive jet production, two high energy hadrons A and B collide and
produce high transverse momentum jets, while hadron A is diffractively
scattered. Ingelman and Schlein predicted this phenomenon. In their model, part
of the longitudinal momentum transferred from hadron A is delivered to the jet
system, part is lost. Lossless diffractive jet production, in which all of this
longitudinal momentum is delivered to the jet system, has been discussed by
Collins, Frankfurt, and Strikman. We study the structure of lossless
diffractive jet production in a simple model. The model suggests that the
phenomenon can be probed experimentally at HERA, with A being a proton and B
being a bremsstrahlung photon with virtuality . Lossless events should be
present for small , but not for larger than , where
is a characteristic size of the pomeron.Comment: 23 pages, REVTeX 3.0 with 8 postscript figures compressed with
uufiles, OITS 536 and AZPH-TH/94-0
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