1,742 research outputs found
The double parton distributions in the hard pomeron model
We study the double parton interaction process in collisions between highly
virtual pairs in the BFKL regime. Explicit expressions for the
double parton distributions are obtained both in the case of direct coupling of
the BFKL pomerons to the pair and in the case of triple pomeron
interaction.Comment: 29 pages, 6 figure
The N - Jet Inclusive Cross-Section in the Hard Pomeron Model
The inclusive production of several jets is studied in the framework of the
hard pomeron model. The average jet momenta are found to be strongly ordered
and growing towards the central c.m. rapidity, as expected. Strong positive
correlations are found for pairs of jets neighbouring in rapidity, both in the
forward-backward and forward-forward directions.Comment: 20 pages, latex, one figure (fig.2), an hard copy of fig.1 can be
obtained on reques
The bootstrap for impact factors and the gluon wave function
Using the results recently obtained for the non-forward quark and gluon
impact factors, it is shown that their form in the gluon colour channel is
consistent with the ``third bootstrap condition'', namely, that they should be
proportional to the gluon wave function. The gluon wave function found from
this assumption is used to write the full bootstrap condition for the gluonic
potential in the next-to-leading order.Comment: Latex, 7 page
Energy loss as the origin of an universal scaling law of the elliptic flow
It is shown that the excellent scaling of the elliptic flow found for all
centralities, species and energies from RHIC to the LHC for less than
the saturation momentum is a consequence of the energy lost by a parton
interacting with the color field produced in a nucleus-nucleus collision. In
particular, the deduced shape of the scaling curve describes correctly all the
data. We discuss the possible extensions to higher , proton-nucleus and
proton-proton collisions as well as higher harmonics.Comment: 10 pages, 2 figure
Evolution of the gluon density in x with a running coupling constant
This is a draft describing the calculation of the evolution of the gluon
density in from an initial value to smaller values, up to
in the hard pomeron formalism with a running coupling introduced on
the basis of the bootstrap equation. The obtained gluon density is used to
calculate the singlet part of the proton structure function. Comparison with
experiment and the results following from the fixed coupling evolution is made.Comment: 10 pages, Latex, 10 postscript figure
Jet production from the perturbative QCD pomeron with a running coupling constant
An analysis of minijet production from the hard pomeron with a running
coupling constant is performed. Two supercritical pomerons found in the
numerical study are taken into account. The calculated inclusive jet production
rate is finite at small and behaves like at high
modulo factors coming from logarithmic terms. The average
is found to be very large () and practically independent of
energy. This is interpreted as an indication that at present energies we are
still far from the asymptotics and that, apart from supercritical pomerons,
other states contribute significantly
The Effectiveness of using Total System Power for Fault Detection in Rooftop Units
Previous research has been presented that suggests using instantaneous system power measurements can be used to perform fault detection for rooftop units. The methodology generates a normal system power model using measurements of system power and outdoor-air temperature, which can be then used to determine if system performance has deviated due to the presence of faults. This work presents data collected from several rooftop units subjected to different faults and ambient conditions using psychrometric chamber test facilities. The results of the testing show that total system power is not very sensitive to many common faults affecting direct-expansion air-conditioning equipment. In fact, only condenser fouling faults increase instantaneous power at significant levels. Other faults, such as improper refrigerant charge level, liquid-line restriction, or compressor valve leakage, may lead to total power reduction and also, in general, have relatively weak impacts on total system power.  Virtual sensor measurements of total cooling capacity or coefficient of performance (COP) are more sensitive fault detection indicators than system power
Lab and Field Evaluation of Fault Detection and Diagnostics for Advanced Roof Top Unit
In this paper, the results of lab and field evaluation of several RTU FDD technologies will be presented and discussed. The focus the study was on RTUs that provide cooling of small and medium commercial buildings. This work was conducted by UTRC in close collaboration Purdue University within Consortium for Building Energy Innovation (CBEI). The goal of the lab activity was to engineer and assess low-cost, embeddable fault detection and diagnostics (FDD) for a new RTU product that exceeds DOE\u27s High Performance RTU performance specification. Primary focus of evaluation was on overall unit performance degradation (COP and capacity) resulted from single and multiple operational faults. High confidence and low false alarm rate of COP degradation were demonstrated. The cost effectiveness of FDD will be discussed. Due to high interest and close engagement of Original Equipment Manufacturer (OEM) and National Account Customer field evaluation of FDD became possible. Several commercial sited with state-of-the-art RTUs were instrumented for continues monitoring of RTU performance and assessment of frequency of typical operational faults. Also some operational faults are intentionally injected in order evaluate FDD effectiveness. Several levels of FDD applicable in the field will be discussed
Finite formation time effects in quasi-elastic scattering on nuclear targets
The problem of the final state interaction in quasi-elastic
scattering at large , is investigated by exploiting the idea that the
ejected nucleon needs a finite amount of time to assume its asymptotic form. It
is shown that when the dependence of the scattering amplitude of the ejected
nucleon on its virtuality is taken into account, the final state interaction is
decreased. The developed approach is simpler to implement than the one based on
the color transparency description of the damping of the final state
interaction, and is essentially equivalent to the latter in the case of the
single rescattering term. The process on the deuteron is numerically
investigated and it is shown that, at , appreciable finite formation time
effects at of the order of 10 (GeV/c) are expected.Comment: 23 pages, 3 figure
- …