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Assessing the cross platform performance of marine mammal indicators between two collocated acoustic recorders
Equipment and deployment strategies for remote passive acoustic sensing of marine environments must balance
memory capacity, power requirements, sampling rate, duty-cycle, deployment duration, instrument size, and environmental
concerns. The impact of different parameters on the data and applicability of the data to the specific
questions being asked should be considered before deployment. Here we explore the effect of recording and detection
parameters on marine mammal acoustic data across two platforms. Daily classifications of marine mammal
vocalizations from two passive acoustic monitors with different subsampling parameters, an AURAL and a
Passive Aquatic Listener (PAL), collocated in the Bering Sea were compared. The AURAL subsampled on a preset
schedule, whereas the PAL sampled via an adaptive protocol. Detected signals of interest were manually classified
in each dataset independently. The daily classification rates of vocalizations were similar. Detections from
the higher duty-cycle but lower sample rate AURAL were limited to species and vocalizations with energy below
4 kHz precluding detection of echolocation signals. Temporal coverage from the PAL audio files was limited by
the adaptive sub-sampling protocol. A method for classifying ribbon (Histriophoca fasciata) and bearded seal
(Erignathus barbatus) vocalizations from the sparse spectral time histories of the PAL was developed. Although
application of the acoustic entropy as a rapid assessment of biodiversity was not reflective of the number of species
detected, acoustic entropy was robust to changes in sample rate and window length.Keywords: Acoustic diversity, Marine mammal classification, Spectral detection, Acoustic entropy, Ocean acousticsKeywords: Acoustic diversity, Marine mammal classification, Spectral detection, Acoustic entropy, Ocean acousticsKeywords: Acoustic diversity, Marine mammal classification, Spectral detection, Acoustic entropy, Ocean acoustic
Study of Spin and Decay-Plane Correlations of W Bosons in the e+e- -> W+W- Process at LEP
Data collected at LEP at centre-of-mass energies \sqrt(s) = 189 - 209 GeV are
used to study correlations of the spin of W bosons using e+e- -> W+W- -> lnqq~
events. Spin correlations are favoured by data, and found to agree with the
Standard Model predictions. In addition, correlations between the W-boson decay
planes are studied in e+e- -> W+W- -> lnqq~ and e+e- -> W+W- -> qq~qq~ events.
Decay-plane correlations, consistent with zero and with the Standard Model
predictions, are measured
Ultrarelativistic sources in nonlinear electrodynamics
The fields of rapidly moving sources are studied within nonlinear
electrodynamics by boosting the fields of sources at rest. As a consequence of
the ultrarelativistic limit the delta-like electromagnetic shock waves are
found. The character of the field within the shock depends on the theory of
nonlinear electrodynamics considered. In particular, we obtain the field of an
ultrarelativistic charge in the Born-Infeld theory.Comment: 10 pages, 3 figure
Measurement of the Cross Section for Open-Beauty Production in Photon-Photon Collisions at LEP
The cross section for open-beauty production in photon-photon collisions is
measured using the whole high-energy and high-luminosity data sample collected
by the L3 detector at LEP. This corresponds to 627/pb of integrated luminosity
for electron-positron centre-of-mass energies from 189GeV to 209GeV. Events
containing b quarks are identified through their semi-leptonic decay into
electrons or muons. The e+e- -> e+e-b b~X cross section is measured within our
fiducial volume and then extrapolated to the full phase space. These results
are found to be in significant excess with respect to Monte Carlo predictions
and next-to-leading order QCD calculations
Search for Branons at LEP
We search, in the context of extra-dimension scenarios, for the possible
existence of brane fluctuations, called branons. Events with a single photon or
a single Z-boson and missing energy and momentum collected with the L3 detector
in e^+ e^- collisions at centre-of-mass energies sqrt{s}=189-209$ GeV are
analysed. No excess over the Standard Model expectations is found and a lower
limit at 95% confidence level of 103 GeV is derived for the mass of branons,
for a scenario with small brane tensions. Alternatively, under the assumption
of a light branon, brane tensions below 180 GeV are excluded
Search for Charginos with a Small Mass Difference with the Lightest Supersymmetric Particle at \sqrt{s} = 189 GeV
A search for charginos nearly mass-degenerate with the lightest
supersymmetric particle is performed using the 176 pb^-1 of data collected at
189 GeV in 1998 with the L3 detector. Mass differences between the chargino and
the lightest supersymmetric particle below 4 GeV are considered. The presence
of a high transverse momentum photon is required to single out the signal from
the photon-photon interaction background. No evidence for charginos is found
and upper limits on the cross section for chargino pair production are set. For
the first time, in the case of heavy scalar leptons, chargino mass limits are
obtained for any \tilde{\chi}^{+-}_1 - \tilde{\chi}^0_1 mass difference
Measurement of W Polarisation at LEP
The three different helicity states of W bosons produced in the reaction e+
e- -> W+ W- -> l nu q q~ at LEP are studied using leptonic and hadronic W
decays. Data at centre-of-mass energies \sqrt s = 183-209 GeV are used to
measure the polarisation of W bosons, and its dependence on the W boson
production angle. The fraction of longitudinally polarised W bosons is measured
to be 0.218 \pm 0.027 \pm 0.016 where the first uncertainty is statistical and
the second systematic, in agreement with the Standard Model expectation
Production of Single W Bosons at \sqrt{s}=189 GeV and Measurement of WWgamma Gauge Couplings
Single W boson production in electron-positron collisions is studied with the
L3 detector at LEP. The data sample collected at a centre-of-mass energy of
\sqrt{s} = 188.7GeV corresponds to an integrated luminosity of 176.4pb^-1.
Events with a single energetic lepton or two acoplanar hadronic jets are
selected. Within phase-space cuts, the total cross-section is measured to be
0.53 +/- 0.12 +/- 0.03 pb, consistent with the Standard Model expectation.
Including our single W boson results obtained at lower \sqrt{s}, the WWgamma
gauge couplings kappa_gamma and lambda_gamma are determined to be kappa_gamma =
0.93 +/- 0.16 +/- 0.09 and lambda_gamma = -0.31 +0.68 -0.19 +/- 0.13
Search for Anomalous Couplings in the Higgs Sector at LEP
Anomalous couplings of the Higgs boson are searched for through the processes
e^+ e^- -> H gamma, e^+ e^- -> e^+ e^- H and e^+ e^- -> HZ. The mass range 70
GeV < m_H < 190 GeV is explored using 602 pb^-1 of integrated luminosity
collected with the L3 detector at LEP at centre-of-mass energies
sqrt(s)=189-209 GeV. The Higgs decay channels H -> ffbar, H -> gamma gamma, H
-> Z\gamma and H -> WW^(*) are considered and no evidence is found for
anomalous Higgs production or decay. Limits on the anomalous couplings d, db,
Delta(g1z), Delta(kappa_gamma) and xi^2 are derived as well as limits on the H
-> gamma gamma and H -> Z gamma decay rates
Measurement of W Polarisation at LEP
The three different helicity states of W bosons produced in the reaction e+
e- -> W+ W- -> l nu q q~ at LEP are studied using leptonic and hadronic W
decays. Data at centre-of-mass energies \sqrt s = 183-209 GeV are used to
measure the polarisation of W bosons, and its dependence on the W boson
production angle. The fraction of longitudinally polarised W bosons is measured
to be 0.218 \pm 0.027 \pm 0.016 where the first uncertainty is statistical and
the second systematic, in agreement with the Standard Model expectation
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