startrack predictions of the stochastic gravitational-wave background from compact binary mergers

We review current understanding of kilonova/macronova emission from compact binary mergers (mergers of two neutron stars or a neutron star and a black hole). Kilonova/macronova is emission powered by radioactive decays ofr-process nuclei and it is one of the most promising electromagnetic counterparts of gravitational wave sources. Emission from the dynamical ejecta of ~0.01M⊙is likely to have a luminosity of ~1040–1041 erg s−1with a characteristic timescale of about 1 week. The spectral peak is located in red optical or near-infrared wavelengths. A subsequent accretion disk wind may provide an additional luminosity or an earlier/bluer emission if it is not absorbed by the precedent dynamical ejecta. The detection of near-infrared excess in short GRB 130603B and possible optical excess in GRB 060614 supports the concept of the kilonova/macronova scenario. At 200 Mpc distance, a typical peak brightness of kilonova/macronova with0.01M⊙ejecta is about 22 mag and the emission rapidly fades to >24 mag within ~10 days. Kilonova/macronova candidates can be distinguished from supernovae by (1) the faster time evolution, (2) fainter absolute magnitudes, and (3) redder colors. Since the high expansion velocity (v~0.1–0.2c) is a robust outcome of compact binary mergers, the detection of smooth spectra will be the smoking gun to conclusively identify the gravitational wave source.

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GW170817: Implications for the Stochastic Gravitational-Wave Background from Compact Binary Coalescences

Physical Review Letters ◽

10.1103/physrevlett.120.091101 ◽

2018 ◽

Vol 120 (9) ◽

Cited By ~ 84

Author(s):

B. P. Abbott ◽

R. Abbott ◽

T. D. Abbott ◽

F. Acernese ◽

K. Ackley ◽

...

Keyword(s):

Gravitational Wave ◽

Compact Binary ◽

Gravitational Wave Background

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Low-Γ jets from Compact Binary Mergers as Candidate Electromagnetic Counterparts to Gravitational Wave Sources

Proceedings of the International Astronomical Union ◽

10.1017/s174392131601228x ◽

2016 ◽

Vol 12 (S324) ◽

pp. 66-69

Author(s):

Gavin P. Lamb ◽

Shiho Kobayashi

Keyword(s):

Gravitational Wave ◽

Gamma Ray ◽

Ambient Medium ◽

Radioactive Decay ◽

Prompt Gamma ◽

Late Time ◽

Astrophysical Jets ◽

Power Law Distribution ◽

Compact Binary ◽

Binary Mergers

AbstractCompact binary mergers, with neutron stars or neutron star and black-hole components, are thought to produce various electromagnetic counterparts: short gamma-ray bursts (GRBs) from ultra-relativistic jets followed by broadband afterglow; semi-isotropic kilonova from radioactive decay of r-process elements; and late time radio flares; etc. If the jets from such mergers follow a similar power-law distribution of Lorentz factors as other astrophysical jets then the population of merger jets will be dominated by low-Γ values. The prompt gamma-rays associated with short GRBs would be suppressed for a low-Γ jet and the jet energy will be released as X-ray/optical/radio transients when a shock forms in the ambient medium. Using Monte Carlo simulations, we study the properties of such transients as candidate electromagnetic counterparts to gravitational wave sources detectable by LIGO/Virgo. Approximately 78% of merger-jets result in failed GRB with optical peaks 14-22 magnitude and an all-sky rate of 2-3 per year.

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Quantum expander for gravitational-wave observatories

Light Science & Applications ◽

10.1038/s41377-019-0230-2 ◽

2019 ◽

Vol 8 (1) ◽

Cited By ~ 3

Author(s):

Mikhail Korobko ◽

Yiqiu Ma ◽

Yanbei Chen ◽

Roman Schnabel

Keyword(s):

Gravitational Wave ◽

Laser Light ◽

Low Frequency ◽

Optical Resonators ◽

High Signal ◽

Quantum Uncertainty ◽

Frequency Sensitivity ◽

The Past ◽

Compact Binary ◽

Binary Mergers

AbstractThe quantum uncertainty of laser light limits the sensitivity of gravitational-wave observatories. Over the past 30 years, techniques for squeezing the quantum uncertainty, as well as for enhancing gravitational-wave signals with optical resonators have been invented. Resonators, however, have finite linewidths, and the high signal frequencies that are produced during the highly scientifically interesting ring-down of astrophysical compact-binary mergers still cannot be resolved. Here, we propose a purely optical approach for expanding the detection bandwidth. It uses quantum uncertainty squeezing inside one of the optical resonators, compensating for the finite resonators’ linewidths while keeping the low-frequency sensitivity unchanged. This quantum expander is intended to enhance the sensitivity of future gravitational-wave detectors, and we suggest the use of this new tool in other cavity-enhanced metrological experiments.

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Unmodelled clustering methods for gravitational wave populations of compact binary mergers

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stz1938 ◽

2019 ◽

Vol 488 (3) ◽

pp. 3810-3817 ◽

Cited By ~ 5

Author(s):

Jade Powell ◽

Simon Stevenson ◽

Ilya Mandel ◽

Peter Tiňo

Keyword(s):

Gravitational Wave ◽

Gaussian Mixture ◽

Difficult Case ◽

Clustering Methods ◽

Compact Binaries ◽

Mass Distributions ◽

Compact Binary ◽

Binary Mergers ◽

Spin Distributions ◽

Mixture Model Clustering

ABSTRACT The mass and spin distributions of compact binary gravitational-wave sources are currently uncertain due to complicated astrophysics involved in their formation. Multiple sub-populations of compact binaries representing different evolutionary scenarios may be present amongst sources detected by Advanced LIGO and Advanced Virgo. In addition to hierarchical modelling, unmodelled methods can aid in determining the number of sub-populations and their properties. In this paper, we apply Gaussian mixture model clustering to 1000 simulated gravitational-wave compact binary sources from a mixture of five sub-populations. Using both mass and spin as input parameters, we determine how many binary detections are needed to accurately determine the number of sub-populations and their mass and spin distributions. In the most difficult case that we consider, where two sub-populations have identical mass distributions but differ in their spin, which is poorly constrained by gravitational-wave detections, we find that ∼400 detections are needed before we can identify the correct number of sub-populations.

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On the gravitational wave background from compact binary coalescences in the band of ground-based interferometers

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stt207 ◽

2013 ◽

Vol 431 (1) ◽

pp. 882-899 ◽

Cited By ~ 50

Author(s):

X.-J. Zhu ◽

E. J. Howell ◽

D. G. Blair ◽

Z.-H. Zhu

Keyword(s):

Gravitational Wave ◽

Compact Binary ◽

Gravitational Wave Background

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Time-dependence of the astrophysical stochastic gravitational wave background

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stz3226 ◽

2019 ◽

Cited By ~ 4

Author(s):

Suvodip Mukherjee ◽

Joseph Silk

Keyword(s):

Gravitational Wave ◽

Temporal Variations ◽

Observation Time ◽

Time Translation ◽

Translation Symmetry ◽

Binary Mergers ◽

Statistical Time ◽

Event Rates ◽

Observation Times ◽

Gravitational Wave Background

Abstract The astrophysical stochastic gravitational wave background (SGWB) is mostly produced from unresolved stellar binary mergers, and the number of events at any moment of time is expected to be Poisson-distributed. The event rate is governed by several astrophysical processes. The Poisson nature leads to variation in the number of sources and this causes temporal variations in the SGWB. The intrinsic temporal fluctuations of the SGWB are a rich source of astrophysical information that can be explored via ongoing and future gravitational wave experiments to classify the sources of the SGWB signal. Along with several other methods to estimate the GW event rates from individual sources, the study of the temporal variations of the SGWB signal provides an independent method for estimating the event rates of the GW sources that contribute to the SGWB. Along with direct estimates of event rates, this approach can also distinguish between different sources contributing to the SGWB signal and will be a useful probe of its evolution over a vast cosmic volume. On averaging over observation times, the SGWB will be statistically invariant under time translation. Statistical time translation symmetry of the SGWB is expected due to the negligible evolution of the relevant cosmological and astrophysical phenomena over the observation time-scales over which the data is collected.

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