559 research outputs found
Tau Electroweak Couplings
We review world-average measurements of the tau lepton electroweak couplings,
in both decay (including Michel parameters) and in production ( and W^-\to\tau^-\nubar_\tau). We review the searches for
anomalous weak and EM dipole couplings. Finally, we present the status of
several other tau lepton studies: searches for lepton flavor violating decays,
neutrino oscillations, and tau neutrino mass limits.Comment: 12 pages, 16 figures; talk presented at Heavy Flavours 8,
Southampton, UK, 199
Experimental Limits on Weak Annihilation Contributions to b → ulv Decays
We present the first experimental limits on high-q^2 contributions to charmless semileptonic B decays of the form expected from the weak annihilation (WA) decay mechanism. Such contributions could bias determinations of |V_(ub)| from inclusive measurements of B→X_ulν. Using a wide range of models based on available theoretical input we set a limit of Γ_(WA)/Γ_(b→u) <7.4% (90% confidence level) on the WA fraction, and assess the impact on previous inclusive determinations of |V_(ub)|
Probing gravitational wave polarizations with signals from compact binary coalescences
In this technical note, we study the possibility of using networks of
ground-based detectors to directly measure gravitational-wave polarizations
using signals from compact binary coalescences. We present a simple data
analysis method to partially achieve this, assuming presence of a strong signal
well-captured by a GR template.Comment: Technical not
Detecting Beyond-Einstein Polarizations of Continuous Gravitational Waves
The direct detection of gravitational waves with the next generation
detectors, like Advanced LIGO, provides the opportunity to measure deviations
from the predictions of General Relativity. One such departure would be the
existence of alternative polarizations. To measure these, we study a single
detector measurement of a continuous gravitational wave from a triaxial pulsar
source. We develop methods to detect signals of any polarization content and
distinguish between them in a model independent way. We present LIGO S5
sensitivity estimates for 115 pulsars.Comment: submitted to PR
Observation of B_s Production at the Y(5S) Resonance
Using the CLEO detector at the Cornell Electron Storage Ring, we have observed the B_s meson in e^+e^- annihilation at the Υ(5S) resonance. We find 14 candidates consistent with B_s decays into final states with a J/ψ or a D_s^((*)-). The probability that we have observed a background fluctuation is less than 8×10^(-10). We have established that at the energy of the Υ(5S) resonance B_s production proceeds predominantly through the creation of B_s^*B̅ _s^* pairs. We find σ(e^+e^-→B^s^*B̅ ^*)=[0.11_(-0.03)^(+0.04)(stat)±0.02(syst)] nb, and set the following limits: σ(e^+e^-→B_sB̅ _s)/σ(e^+e^-→B_s^*B̅ _s^*)<0.16 and [σ(e^+e^-→B_sB̅ _s^*)+σ(e^+e^-→B_s*B̅ _s)]/σ(e^+e^-→B_s*B̅ _s^*)<0.16 (90% C.L.). The mass of the B_s^* meson is measured to be M_(B_s^*=[5.414±0.001(stat)±0.003(syst)] GeV/c^2
Two-photon width of the charmonium state X_(c2)
The two-photon width of X_(c2)^3P_2 state of charmonium has been measured using 14.4 fb^(-1) of e^+e^-data taken at √s
=9.46–11.30 GeV with the CLEO III detector. The yy-fusion reaction studied is e^+e^- → e^+e^-yy, → yy X_(c2) → yJ/Ψ → ye^+e^-(µ^+µ^-). We measure Г_(yy) (X_(c2))B(X_(c2)) → y
J/Ψ)B(J/Ψ → e^+e^- + µ^+µ^-)= 13.2 ± 1.4(stat)± 1.1(syst) eV, and obtain Г yy(Xc2)= 559 ± 57(stat) ± 48(syst) ± 36(br) eV. This result is in excellent agreement with the result of -fusion measurement by Belle and is consistent with that of the pp → X_(c2) → yy measurement, when they are both reevaluated using the recent CLEO result for the radiative decay X_(c2) → J/Ψ
Frequency response of space-based interferometric gravitational-wave detectors
Gravitational waves are perturbations of the metric of space-time. Six
polarizations are possible, although general relativity predicts that only two
such polarizations, tensor plus and tensor cross are present for gravitational
waves. We give the analytical formulas for the antenna response functions for
the six polarizations which are valid for any equal-arm interferometric
gravitational-wave detectors without optical cavities in the arms.The response
function averaged over the source direction and polarization angle decreases at
high frequencies which deteriorates the signal-to-noise ratio registered in the
detector. At high frequencies, the averaged response functions for the tensor
and breathing modes fall of as , the averaged response function for the
longitudinal mode falls off as and the averaged response function for the
vector mode falls off as .Comment: V3: minor corrections. PRD in pres
Calculus Unlimited
Purpose: This book is intended to supplement our text, Calculus (Benjamin/Cummings, 1980), or virtually any other calculus text (see page vii, How To Use This Book With Your Calculus Text). As the title Calculus Unlimited implies, this text presents an alternative treatment of calculus using the method of exhaustion for the derivative and integral in place of limits. With the aid of this method, a definition of the derivative may be introduced in the first lecture of a calculus course for students who are familiar with functions and graphs.
Approach: Assuming an intuitive understanding of real numbers, we begin in Chapter 1 with the definition of the derivative. The axioms for real numbers are presented only when needed, in the discussion of continuity. Apart from this, the development is rigorous and contains complete proofs.
As you will note, this text has a more geometric flavor than the usual analytic treatment of calculus. For example, our definition of completeness is in terms of convexity rather than least upper bounds, and Dedekind cuts are replaced by the notion of a transition point.
Who Should Use This Book: This book is for calculus instructors and students interested in trying an alternative to limits. The prerequisites are a knowledge of functions, graphs, high school algebra and trigonometry.
How To Use This Book: Because the "learning-by-doing" technique introduced in Calculus has proved to be successful, we have adapted the same format for this book. The solutions to "Solved Exercises" are provided at the back of the book; however readers are encouraged to try solving each example before looking up the solution.
The Origin Of The Definition of The Derivative: Several years ago while reading Geometry and the Imagination, by Hilbert and Cohn-Vossen (Chelsea, 1952, p. 176), we noticed a definition of the circle of curvature for a plane curve C. No calculus, as such, was used in this definition. This suggested that the same concept could be used to define the tangent line and thus serve as a limit-free foundation for the differential calculus. We introduced this new definition of the derivative into our class notes and developed it in our calculus classes for several years. As far as we know, the definition has not appeared elsewhere. If our presumption of originality is ill-founded, we welcome your comments.
Jerrold Marsden
Alan Weinstein
Berkeley, C
Calculus I
Preface: The goal of this text is to help students learn to use calculus intelligently for solving a wide variety of mathematical and physical problems.
This book is an outgrowth of our teaching of calculus at Berkeley, and the present edition incorporates many improvements based on our use of the first edition...
A comparison theorem for Hamiltonian vector fields
The question of completeness of Hamiltonian systems is investigated for a class of potentials not necessarily bounded below. The result generalizes previous work of W. Gordon and D. Ebin
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