3,462 research outputs found
TRADE AND POLICY IMPLICATIONS OF THE WHEAT DISEASE KARNAL BUNT
Agricultural and Food Policy, International Relations/Trade,
SETTING INTERNATIONAL STANDARDS FOR FOOD AND AGRICULTURAL TRADE
International Relations/Trade,
Impact of Numerical Relativity information on effective-one-body waveform models
We present a comprehensive comparison of the spin-aligned effective-one-body
(EOB) waveform model of Nagar et al. [Phys. Rev. D93, 044046 (2016)], informed
using 40 numerical-relativity (NR) datasets, against a set of 149, ,
NR waveforms freely available through the Simulation Extreme Spacetime (SXS)
catalog. We find that, without further calibration, these EOBNR waveforms have
unfaithfulness (at design Advanced-LIGO sensitivity and evaluated with total
mass varying as ) always below
against all NR waveforms except for three outliers, that still never exceed the
level; with a minimal retuning of the (effective)
next-to-next-to-next-to-leading-order spin-orbit coupling parameter for the
non-equal-mass and non-equal-spin sector, that only needs three more NR
waveforms, one is left with another two (though different) outliers, with
maximal unfaithfulness of up to only for a total mass of . We
show this is the effect of slight inaccuracies in the phenomenological
description of the postmerger waveform of Del Pozzo and Nagar
[arXiv:1606.03952] that was constructed by interpolating over only 40NR
simulations. We argue that this is easily fixed by using either an alternative
ringdown description (e.g., the superposition of quasi-normal-modes) or an
improved version of the phenomenological representation. By analyzing a NR
waveform with mass ratio and dimensionless spins obtained with the
BAM code, we conclude that the model would benefit from NR simulations
specifically targeted at improving the postmerger-ringdown phenomenological
fits for mass ratios and spins .Comment: 24 pages, 20 figures, submitted to Phys. Rev.
A Multipolar Effective One Body Model for Non-Spinning Black Hole Binaries
We introduce \TEOBiResumSM{}, a nonspinning inspiral-merger-ringdown waveform
model built within the effective one body (EOB) framework that includes
gravitational waveform modes beyond the dominant quadrupole . The model incorporates: (i) an improved Pad\'e resummation of the
factorized waveform amplitudes entering the
EOB-resummed waveform where the 3PN, mass-ratio dependent, terms are hybridized
with test-mass limit terms up to 6PN relative order for most of the multipoles
up to included; (ii) an improved determination of the effective 5PN
function entering the EOB interaction potential done using the
most recent, error-controlled, nonspinning numerical relativity (NR) waveforms
from the Simulating eXtreme Spacetimes (SXS) collaboration; and (iii) a
NR-informed phenomenological description of the multipolar ringdown. Such
representation stems from 19 NR waveforms with mass ratios up to
as well as test-mass waveform data, although it does not incorporate
mode-mixing effects. The NR-completed higher modes through merger and ringdown
considered here are: . For simplicity, the other subdominant modes,
up to , are approximated by the corresponding, purely analytical,
factorized and resummed EOB waveform. To attempt an estimate of (some of) the
underlying analytic uncertainties of the model, we also contrast the effect of
the 6PN-hybrid Pad\'e-resummed 's with the standard PN,
Taylor-expanded, ones used in previous EOB works. The maximum unfaithfulness
against the SXS waveforms including all NR-completed modes up to
is always for binaries with total mass as .Comment: 24 pages, 18 figures. Improved figures and presentation. Submitted to
Phys. Rev.
Box spline prewavelets of small support
The purpose of this paper is the construction of bi- and trivariate prewavelets from box-spline spaces, \ie\ piecewise polynomials of fixed degree on a uniform mesh. They have especially small support and form Riesz bases of the wavelet spaces, so they are stable. In particular, the supports achieved are smaller than those of the prewavelets due to Riemenschneider and Shen in a recent, similar constructio
Why Not a China Pattern
Her luncheon was a great success. How could it be otherwise? Her table appointments were faultless and the service perfect in every respect
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