333,113 research outputs found
Semileptonic decays of the Higgs boson at the Tevatron
We examine the prospects for extending the Tevatron reach for a Standard
Model Higgs boson by including the semileptonic Higgs boson decays h --> WW -->
l nu jj for M_h >~ 2 M_W, and h --> W jj --> l nu jj for M_h <~ 2 M_W, where j
is a hadronic jet. We employ a realistic simulation of the signal and
backgrounds using the Sherpa Monte Carlo event generator. We find kinematic
selections that enhance the signal over the dominant W+jets background. The
resulting sensitivity could be an important addition to ongoing searches,
especially in the mass range 120 <~ M_h <~ 150 GeV. The techniques described
can be extended to Higgs boson searches at the Large Hadron Collider.Comment: 68 pages, 19 figure
EPR-B correlations: a physically tenable local-real model
We propose a classical, i.e., local-real physical model of processes
underlying EPR experiments. The model leads to the prediction, that the
visibility of the output signal will exhibit increasing variation as the
coincidence window is increased, thus providing a testable criteria for its
validity. If it can be sustained, this model undermines the claim that Nature
has a fundamentally nonlocal feature or that irreal entities are required by
quantum theory.Comment: 10 pages; latex w/ 2 figure
Towards the timely detection of toxicants
We address the problem of enhancing the sensitivity of biosensors to the
influence of toxicants, with an entropy method of analysis, denoted as
CASSANDRA, recently invented for the specific purpose of studying
non-stationary time series. We study the specific case where the toxicant is
tetrodotoxin. This is a very poisonous substance that yields an abrupt drop of
the rate of spike production at t approximatively 170 minutes when the
concentration of toxicant is 4 nanomoles. The CASSANDRA algorithm reveals the
influence of toxicants thirty minutes prior to the drop in rate at a
concentration of toxicant equal to 2 nanomoles. We argue that the success of
this method of analysis rests on the adoption of a new perspective of
complexity, interpreted as a condition intermediate between the dynamic and the
thermodynamic state.Comment: 6 pages and 3 figures. Accepted for publication in the special issue
of Chaos Solitons and Fractal dedicated to the conference "Non-stationary
Time Series: A Theoretical, Computational and Practical Challenge", Center
for Nonlinear Science at University of North Texas, from October 13 to
October 19, 2002, Denton, TX (USA
Melt homogenization and self-organization of chalcogenides glasses: evidence of sharp rigidity, stress and nanoscale phase separation transitions in the GexSe100-x binary
A Raman profiling method is used to monitor growth of GexSe100-x melts and
reveals a two step process of homogenization. Resulting homogeneous glasses
show the non-reversing enthalpy at Tg, {\Delta}Hnr(x), to show a square-well
like variation with x, with a rigidity transition near xc(1) = 19.5(5)% and
stress transition near xc(2) = 26.0(5)%) representing the boundaries of the
rigid but stress-free Intermediate Phase (IP). The square-well like variation
of {\Delta}Hnr(x) develops sloping walls, a triangular shape and eventually
disappears in glasses having an increasing heterogeneity. The {\Delta}Hnr term
ages over weeks outside the IP but not inside the IP. An optical analogue of
the reversibility window is observed with Raman spectra of as-quenched melts
and Tg cycled glasses being the same for glass compositions in the IP but
different for compositions outside the IP. Variations of Molar volumes, display
three regimes of behavior with a global minimum in the IP and a pronounced
increase outside that phase. The intrinsic physical behavior of dry and
homogeneous chalcogenides glasses can vary sharply with composition near
elastic and chemical phase transitions, showing that the physics of network
glasses requires homogeneous samples, and may be far more interesting than
hitherto recognized
An integrated packet/flow model for TCP performance analysis
Processor sharing (PS) models for TCP behavior nicely capture the bandwidth sharing and statistical multiplexing effect of TCP flows on the flow level. However, these âroughâ models do not provide insight into the impact of packet-level parameters (such as round trip time and buffer size) on, e.g., throughput and flow transfer times. This paper proposes an integrated packet/flow-level model: it exploits the advantages of PS approach on the flow level and, at the same time, it incorporates the most significant packet-level effects
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