38,940 research outputs found
Coherent Network Analysis of Gravitational Waves from Three-Dimensional Core-Collapse Supernova Models
Using predictions from three-dimensional (3D) hydrodynamics simulations of
core-collapse supernovae (CCSNe), we present a coherent network analysis to
detection, reconstruction, and the source localization of the
gravitational-wave (GW) signals. We use the {\tt RIDGE} pipeline for the
analysis, in which the network of LIGO Hanford, LIGO Livingston, VIRGO, and
KAGRA is considered. By combining with a GW spectrogram analysis, we show that
several important hydrodynamics features in the original waveforms persist in
the waveforms of the reconstructed signals. The characteristic excess in the
spectrograms originates not only from rotating core-collapse, bounce and the
subsequent ring down of the proto-neutron star (PNS) as previously identified,
but also from the formation of magnetohydrodynamics jets and non-axisymmetric
instabilities in the vicinity of the PNS. Regarding the GW signals emitted near
at the rotating core bounce, the horizon distance extends up to 18 kpc
for the most rapidly rotating 3D model in this work. Following the rotating
core bounce, the dominant source of the GW emission shifts to the
non-axisymmetric instabilities. The horizon distances extend maximally up to
40 kpc seen from the spin axis. With an increasing number of 3D models
trending towards explosion recently, our results suggest that in addition to
the best studied GW signals due to rotating core-collapse and bounce, the time
is ripe to consider how we can do science from GWs of CCSNe much more seriously
than before. Particularly the quasi-periodic signals due to the
non-axisymmetric instabilities and the detectability should deserve further
investigation to elucidate the inner-working of the rapidly rotating CCSNe.Comment: PRD in pres
Probing Rotation of Core-collapse Supernova with Concurrent Analysis of Gravitational Waves and Neutrinos
The next time a core-collapse supernova (SN) explodes in our galaxy, vari-
ous detectors will be ready and waiting to detect its emissions of
gravitational waves (GWs) and neutrinos. Current numerical simulations have
successfully introduced multi-dimensional effects to produce exploding SN
models, but thus far the explosion mechanism is not well understood. In this
paper, we focus on an investigation of progenitor core rotation via comparison
of the start time of GW emission and that of the neutronization burst. The GW
and neutrino de- tectors are assumed to be, respectively, the KAGRA detector
and a co-located gadolinium-loaded water Cherenkov detector, either EGADS or
GADZOOKS!. Our detection simulation studies show that for a nearby supernova
(0.2 kpc) we can confirm the lack of core rotation close to 100% of the time,
and the presence of core rotation about 90% of the time. Using this approach
there is also po- tential to confirm rotation for considerably more distant
Milky Way supernova explosions.Comment: 31pages, 15figures, submit to Ap
Benefits of Artificially Generated Gravity Gradients for Interferometric Gravitational-Wave Detectors
We present an approach to experimentally evaluate gravity gradient noise, a
potentially limiting noise source in advanced interferometric gravitational
wave (GW) detectors. In addition, the method can be used to provide sub-percent
calibration in phase and amplitude of modern interferometric GW detectors.
Knowledge of calibration to such certainties shall enhance the scientific
output of the instruments in case of an eventual detection of GWs. The method
relies on a rotating symmetrical two-body mass, a Dynamic gravity Field
Generator (DFG). The placement of the DFG in the proximity of one of the
interferometer's suspended test masses generates a change in the local
gravitational field detectable with current interferometric GW detectors.Comment: 16 pages, 4 figure
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