385 research outputs found
Accurate and efficient gravitational waveforms for certain galactic compact binaries
Stellar-mass compact binaries in eccentric orbits are almost guaranteed
sources of gravitational waves for Laser Interferometer Space Antenna. We
present a prescription to compute accurate and efficient gravitational-wave
polarizations associated with bound compact binaries of arbitrary eccentricity
and mass ratio moving in slowly precessing orbits. We compare our approach with
those existing in the literature and present its advantages.Comment: 10 pages, 7 figures, to be published in MNRA
Full-analytic frequency domain gravitational wave forms from eccentric compact binaries to second post-Newtonian accuracy
Full-analytic gravitational wave forms for inspiralling eccentric compact binaries of arbitary mass ratio have been provided in the frequency domain for the case of vanishing spins. Tail terms are not considered. In the given prescription, the semi-analytical property of recent descriptions, which demand inverting the higher order Kepler equation numerically, but keeping all other computations analytic is avoided
Aligned Spins: Orbital Elements, Decaying Orbits, and Last Stable Circular Orbit to high post-Newtonian Orders
In this article the quasi-Keplerian parameterisation for the case that spins
and orbital angular momentum in a compact binary system are aligned or
anti-aligned with the orbital angular momentum vector is extended to 3PN
point-mass, next-to-next-to-leading order spin-orbit, next-to-next-to-leading
order spin(1)-spin(2), and next-to-leading order spin-squared dynamics in the
conservative regime. In a further step, we use the expressions for the
radiative multipole moments with spin to leading order linear and quadratic in
both spins to compute radiation losses of the orbital binding energy and
angular momentum. Orbital averaged expressions for the decay of energy and
eccentricity are provided. An expression for the last stable circular orbit is
given in terms of the angular velocity type variable .Comment: 30 pages, 2 figures, v2: update to match published versio
Local Current Distribution and "Hot Spots" in the Integer Quantum Hall Regime
In a recent experiment, the local current distribution of a two-dimensional
electron gas in the quantum Hall regime was probed by measuring the variation
of the conductance due to local gating. The main experimental finding was the
existence of "hot spots", i.e. regions with high degree of sensitivity to local
gating, whose density increases as one approaches the quantum Hall transition.
However, the direct connection between these "hot spots" and regions of high
current flow is not clear. Here, based on a recent model for the quantum Hall
transition consisting of a mixture of perfect and quantum links, the relation
between the "hot spots" and the current distribution in the sample has been
investigated. The model reproduces the observed dependence of the number and
sizes of "hot spots" on the filling factor. It is further demonstrated that
these "hot spots" are not located in regions where most of the current flows,
but rather, in places where the currents flow both when injected from the left
or from the right. A quantitative measure, the harmonic mean of these currents
is introduced and correlates very well with the "hot spots" positions
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