747 research outputs found
The Weak Tie Between Natural Gas and Oil Prices
Several recent studies establish that crude oil and natural gas prices are cointegrated, so that changes in the price of oil appear to translate into changes in the price of natural gas. Yet at times in the past, and very powerfully in the last two years, many voices have noted that the two prices series appear to have "decoupled". We explore the apparent contradiction between these two views. Although we also find that the two series are cointegrated, recognition of the statistical fact of cointegration needs to be tempered with two additional points that we think have been insufficiently emphasized in the past literature. First, there is an enormous amount of unexplained volatility in natural gas prices at short horizons. Hence, any simple formulaic relationship between the price of oil and the price of natural gas will leave a large portion of the price of natural gas unexplained. Second, the cointegrating relationship does not appear to be stable through time. Natural gas prices may be tied to oil prices, but the relationship can shift dramatically over time. Therefore, although the two price series are cointegrated, the confidence intervals for both short and long time horizons are large.Massachusetts Institute of Technology. Center for Energy and Environmental Policy Researc
Kaon decay interferometry as meson dynamics probes
We discuss the time dependent interferences between and in the
decays in and , to be studied at interferometry machines
such as the -factory and LEAR. We emphasize the possibilities and the
advantages of using interferences, in comparison with width measurements, to
obtain information both on conserving and violating amplitudes.
Comparison with present data and suggestions for future experiments are made.Comment: 15 pages, in RevTex, Report INFNNA-IV-93-31, UTS-DFT-93-2
Final State Interactions and CP Violation in
Using chiral perturbation theory we calculate the imaginary parts of the form factors that arise from and
rescattering. We discuss their influence on CP violating variables in .Comment: ; 12 pages, 2 figures, TeX format; uses epsf.tex, tables.tex, and
phyzzx.te
SELEX RICH Performance and Physics Results
SELEX took data in the 1996/7 Fixed Target Run at Fermilab. The excellent
performance parameters of the SELEX RICH Detector had direct influence on the
quality of the obtained physics results.Comment: Contributed talk at the Fourth Workshop on RICH Detectors, June 5-10,
2002, Pylos, Greece. Accepted for publication in NIM
The Chicagoland Observatory Underground for Particle Physics cosmic ray veto system
A photomultiplier (PMT) readout system has been designed for use by the cosmic ray veto systems of two warm liquid bubble chambers built at Fermilab by the Chicagoland Observatory Underground for Particle Physics (COUPP) collaboration. The systems are designed to minimize the infrastructure necessary for installation. Up to five PMTs can be daisy-chained on a single data link using standard Category 5 network cable. The cables is also serve distribute to low voltage power. High voltage is generated locally on each PMT base. Analog and digital signal processing is also performed locally. The PMT base and system controller design and performance measurements are presented
Measurements of the Decay
The E799-II (KTeV) experiment at Fermilab has collected 83262 events above a background of 79 events. We measure a decay width,
normalized to the (\pi^0 \to \gamma\gamma, \pi^0 to
\gamma\gamma, \pi^0_D \to e^+e^-\gamma) decay width, of K_L \to
e^+e^-\gamma. We also measure parameters of two form factor models. In the Bergstrom, Masso, and Singer
(BMS) parametrization, we find \caks = -0.517 \pm 0.030_{stat} \pm
0.022_{syst}. We separately fit for the first parameter of the D'Ambrosio,
Isidori, and Portoles (DIP) model and find \adip = -1.729 \pm 0.043_{stat} \pm
0.028_{syst}.Comment: 5 pages, 3 figures, submitted to PR
Improved KL->pi e nu Form Factor and Phase Space Integral with Reduced Model Uncertainty
Using the published KTeV sample of 2 million KL-> pi e nu decays and a new
form factor expansion with a rigorous bound on higher order terms, we present a
new determination of the KL->pi e nu form factor and phase space integral.
Compared to the previous KTeV result, the uncertainty in the new form factor
expansion is negligible and results in an overall uncertainty in the phase
space integral (IKe) that is a factor of two smaller: IKe = 0.15392 +- 0.00048
\.Comment: 3 pages, 2 figures, submitted to PRD Rapid Communicatio
Quartz Cherenkov Counters for Fast Timing: QUARTIC
We have developed particle detectors based on fused silica (quartz) Cherenkov
radiators read out with micro-channel plate photomultipliers (MCP-PMTs) or
silicon photomultipliers (SiPMs) for high precision timing (Sigma(t) about
10-15 ps). One application is to measure the times of small angle protons from
exclusive reactions, e.g. p + p - p + H + p, at the Large Hadron Collider, LHC.
They may also be used to measure directional particle fluxes close to external
or stored beams. The detectors have small areas (square cm), but need to be
active very close (a few mm) to the intense LHC beam, and so must be radiation
hard and nearly edgeless. We present results of tests of detectors with quartz
bars inclined at the Cherenkov angle, and with bars in the form of an "L" (with
a 90 degree corner). We also describe a possible design for a fast timing
hodoscope with elements of a few square mm.Comment: 24 pages, 14 figure
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