4,535 research outputs found
Texture of fermion mass matrices in partially unified theories
We investigate the texture of fermion mass matrices in theories with partial
unification (for example ) at a scale
GeV. Starting with the low energy values of the masses and the
mixing angles, we find only two viable textures with atmost four texture zeros.
One of these corresponds to a somewhat modified Fritzsch textures. A
theoretical derivataion of these textures leads to new interesting relations
among the masses and the mixing angles.Comment: 10 pages(Latex
First Astronomical Use of Multiplexed Transition Edge Bolometers
We present performance results based on the first astronomical use of multiplexed superconducting bolometers. The Fabry-Perot Interferometer Bolometer Research Experiment
(FIBRE) is a broadband submillimeter spectrometer that achieved first light in June 2001 at the Caltech Submillimeter Observatory (CSO). FIBRE'S detectors are superconducting transition edge sensor (TES) bolometers read out by a SQUID multiplexer. The Fabry-Perot uses a low
resolution grating to order sort the incoming light. A linear bolometer array consisting of 16 elements detects this dispersed light, capturing 5 orders simultaneously from one position on the sky. With tuning of the Fabry-Perot over one free spectral range, a spectrum covering Δλ/λ= 1/7 at a resolution of δλ/λ ≈ 1/1200 can be acquired. This spectral resolution is sufficient to resolve
Doppler-broadened line emission from external galaxies. FIBRE operates in the 350 µm and 450 µm bands. These bands cover line emission from the important star formation tracers neutral
carbon [Cl] and carbon monoxide (CO). We have verified that the multiplexed bolometers are
photon noise limited even with the low power present in moderate resolution spectrometry
Conformal Rule-Based Multi-label Classification
We advocate the use of conformal prediction (CP) to enhance rule-based
multi-label classification (MLC). In particular, we highlight the mutual
benefit of CP and rule learning: Rules have the ability to provide natural
(non-)conformity scores, which are required by CP, while CP suggests a way to
calibrate the assessment of candidate rules, thereby supporting better
predictions and more elaborate decision making. We illustrate the potential
usefulness of calibrated conformity scores in a case study on lazy multi-label
rule learning
Plausibility functions and exact frequentist inference
In the frequentist program, inferential methods with exact control on error
rates are a primary focus. The standard approach, however, is to rely on
asymptotic approximations, which may not be suitable. This paper presents a
general framework for the construction of exact frequentist procedures based on
plausibility functions. It is shown that the plausibility function-based tests
and confidence regions have the desired frequentist properties in finite
samples---no large-sample justification needed. An extension of the proposed
method is also given for problems involving nuisance parameters. Examples
demonstrate that the plausibility function-based method is both exact and
efficient in a wide variety of problems.Comment: 21 pages, 5 figures, 3 table
Coherent Control of Isotope Separation in HD+ Photodissociation by Strong Fields
The photodissociation of the HD+ molecular ion in intense short- pulsed
linearly polarized laser fields is studied using a time- dependent wave-packet
approach where molecular rotation is fully included. We show that applying a
coherent superposition of the fundamental radiation with its second harmonic
can lead to asymmetries in the fragment angular distributions, with significant
differences between the hydrogen and deuterium distributions in the long
wavelength domain where the permanent dipole is most efficient. This effect is
used to induce an appreciable isotope separation.Comment: Physical Review Letters, 1995 (in press). 4 pages in revtex format, 3
uuencoded figures. Full postcript version available at:
http://chemphys.weizmann.ac.il/~charron/prl.ps or
ftp://scipion.ppm.u-psud.fr/coherent.control/prl.p
The COBE Diffuse Infrared Background Experiment Search for the Cosmic Infrared Background: I. Limits and Detections
The DIRBE on the COBE spacecraft was designed primarily to conduct systematic
search for an isotropic CIB in ten photometric bands from 1.25 to 240 microns.
The results of that search are presented here. Conservative limits on the CIB
are obtained from the minimum observed brightness in all-sky maps at each
wavelength, with the faintest limits in the DIRBE spectral range being at 3.5
microns (\nu I_\nu < 64 nW/m^2/sr, 95% CL) and at 240 microns (\nu I_\nu < 28
nW/m^2/sr, 95% CL). The bright foregrounds from interplanetary dust scattering
and emission, stars, and interstellar dust emission are the principal
impediments to the DIRBE measurements of the CIB. These foregrounds have been
modeled and removed from the sky maps. Assessment of the random and systematic
uncertainties in the residuals and tests for isotropy show that only the 140
and 240 microns data provide candidate detections of the CIB. The residuals and
their uncertainties provide CIB upper limits more restrictive than the dark sky
limits at wavelengths from 1.25 to 100 microns. No plausible solar system or
Galactic source of the observed 140 and 240 microns residuals can be
identified, leading to the conclusion that the CIB has been detected at levels
of \nu I_\nu = 25+-7 and 14+-3 nW/m^2/sr at 140 and 240 microns respectively.
The integrated energy from 140 to 240 microns, 10.3 nW/m^2/sr, is about twice
the integrated optical light from the galaxies in the Hubble Deep Field,
suggesting that star formation might have been heavily enshrouded by dust at
high redshift. The detections and upper limits reported here provide new
constraints on models of the history of energy-releasing processes and dust
production since the decoupling of the cosmic microwave background from matter.Comment: 26 pages and 5 figures, accepted for publication in the Astrophyical
Journa
Intermediate scale as a source of lepton flavor violation in SUSY SO(10)
In supersymmetric SO(10) grand unified models, we examine the lepton flavor
violation process from having the SU(2)U(1) gauge symmetry broken at an intermediate scale below the
SO(10) grand unification scale . Even in the case that supersymmetry is
broken by universal soft terms introduced at the scale , we find
significant rates for with GeV or
less. These rates are further enhanced if the universal soft terms appear at a
scale greater than .Comment: 12 pages (Latex), 3 PS Figures (uuencoded, epsf.tex), small addition
to discussion in the text, as to appear in Phys. Rev. D Rapid Communication
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Floyd County, Texas : records of wells and springs, drillers' logs, and water analyses, and map showing location of wells and springs (1938)
Map of Floyd County, Texas, showing locations of water wells listed. "Prepared in cooperation with the Geological Survey, United States Department of the Interior, the Bureau of Industrial Chemistry of The University of Texas, the Resettlement Administration, and the Works Progress Administration ground-water survey project number 5072."UT Librarie
Alternative formulations of the theory of evidence based on basic plausibility and commonality assignments
In this paper we introduce indeed two alternative formulations of the theory of evidence by proving that both plausibility and commonality functions share the same combinatorial structure of sum function of belief functions, and computing their Moebius inverses called basic plausibility and commonality assignments. The equivalence of the associated formulations of the ToE is mirrored by the geometric congruence of the related simplices. Applications to the probabilistic approximation problem are briefly presented
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