DECIGO PATHFINDER

DECIGO Pathfinder (DPF) is a small (~350 kg) satellite orbiting the Earth. DPF was originally proposed as the first milestone mission for a future space gravitational-wave (GW) antenna, DECi-hertz Interferometer Gravitational wave Observatory (DECIGO). In addition to the purpose of space demonstrations for DECIGO, DPF has scientific objectives: observation of GWs from black-hole mergers and monitor of Earth's gravity, as well as establishment of space technologies for high-precision measurements. In this paper, we review the conceptual design, scientific outcomes and the current status of DPF.

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Coalescence of black hole–neutron star binaries

Living Reviews in Relativity ◽

10.1007/s41114-021-00033-4 ◽

2021 ◽

Vol 24 (1) ◽

Author(s):

Koutarou Kyutoku ◽

Masaru Shibata ◽

Keisuke Taniguchi

Keyword(s):

Black Hole ◽

Neutron Star ◽

Gravitational Wave ◽

High Precision ◽

Numerical Relativity ◽

Current Status ◽

Wave Spectra ◽

Tidal Disruption ◽

Merger Process ◽

General Relativistic

AbstractWe review the current status of general relativistic studies for coalescences of black hole–neutron star binaries. First, high-precision computations of black hole–neutron star binaries in quasiequilibrium circular orbits are summarized, focusing on the quasiequilibrium sequences and the mass-shedding limit. Next, the current status of numerical-relativity simulations for the merger of black hole–neutron star binaries is described. We summarize our understanding for the merger process, tidal disruption and its criterion, properties of the merger remnant and ejected material, gravitational waveforms, and gravitational-wave spectra. We also discuss expected electromagnetic counterparts to black hole–neutron star coalescences.

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The development of ground based gravitational wave astronomy and opportunities for Australia–China collaboration

International Journal of Modern Physics A ◽

10.1142/s0217751x15450190 ◽

2015 ◽

Vol 30 (28n29) ◽

pp. 1545019

Author(s):

David Blair ◽

Li Ju ◽

Chunnong Zhao ◽

Linqing Wen ◽

Qi Chu ◽

...

Keyword(s):

Black Hole ◽

Neutron Star ◽

Gravitational Wave ◽

Gravitational Waves ◽

Southern Hemisphere ◽

Event Rate ◽

Wave Spectrum ◽

Current Status ◽

Dramatic Improvement ◽

The Universe

This paper begins by reviewing the development of gravitational wave astronomy from the first predictions of gravitational waves to development of technologies across the entire gravitational wave spectrum, and then focuses on the current status of ground based gravitational wave detectors. With substantial improvements already demonstrated in early commissioning it is emphasised that Advanced detectors are on track for first detection of gravitational waves. The importance of a worldwide array of detectors is emphasised, and recent results are shown that demonstrate the continued advantage of a southern hemisphere detector. Finally it is shown that a north–south pair of 8 km arm length detectors would give rise to a dramatic improvement in event rate, enabling a pair of detectors to encompass a 64-times larger volume of the universe, to conduct a census on all stellar mass black hole mergers to [Formula: see text] and to observe neutron star mergers to a distance of [Formula: see text][Formula: see text]800 Mpc.

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Update on the European Pulsar Timing Array

Proceedings of the International Astronomical Union ◽

10.1017/s1743921312023575 ◽

2012 ◽

Vol 8 (S291) ◽

pp. 180-180 ◽

Cited By ~ 1

Author(s):

Kuo Liu

Keyword(s):

Gravitational Wave ◽

High Precision ◽

Single Site ◽

Current Status ◽

Radio Telescopes ◽

Millisecond Pulsars ◽

Pulsar Timing ◽

Pulsar Timing Array

AbstractThe European Pulsar Timing Array (EPTA) is one the of three global Pulsar Timing Array communities, aiming to use the clock nature of pulsars to detect gravitational wave. In this talk, I will provide an introduction to the current status of EPTA pulsar observations and present an overview of the recent results. I will also give an update on the progress of the Large European Array for Pulsar (LEAP) project, which attempts to coherently combine the data from the five biggest single site radio telescopes in Europe and make an equivalently 200-metre diameter dish. The LEAP project is an ideal effort in performing high precision pulsar timing and studying characteristics of single pulses from millisecond pulsars.

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On the small-scale clustering of quasars: constraints from the MassiveBlack II simulation

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stz519 ◽

2019 ◽

Vol 485 (2) ◽

pp. 2026-2040 ◽

Cited By ~ 6

Author(s):

Aklant K Bhowmick ◽

Tiziana DiMatteo ◽

Sarah Eftekharzadeh ◽

Adam D Myers

Keyword(s):

Black Hole ◽

Dark Matter ◽

High Precision ◽

Luminosity Function ◽

Core Sample ◽

Precision Measurements ◽

Small Scale ◽

Hydrodynamic Simulation ◽

Black Hole Masses ◽

Simulation Volume

Abstract We examine recent high-precision measurements of small-scale quasar clustering (at z ∼ 0.5–2 on scales of ${\sim }25~\mathrm{kpc}\, h^{-1}$) from the SDSS in the context of the MassiveBlack II (MBII) cosmological hydrodynamic simulation and conditional luminosity function (CLF) modelling. At these high luminosities (g < 20.85 quasars), the MBII simulation volume ($100~\mathrm{cMpc}\, h^{-1}$ comoving boxsize) has only three quasar pairs at distances of 1–4 Mpc. The black hole masses for the pairs range between $M_{\rm bh}\sim 1{\, \rm and\, }3\times 10^{9}~\mathrm{M}_{\odot }\, h^{-1}$ and the quasar hosts are haloes of $M_{\rm h}\sim 1\hbox{--}3\times 10^{14}~\mathrm{M}_{\odot }\, h^{-1}$. Such pairs show signs of recent major mergers in the MBII simulation. By modelling the central and satellite AGN CLFs as lognormal and Schechter distributions, respectively (as seen in MBII AGNs), we arrive at CLF models which fit the simulation predictions and observed luminosity function and the small-scale clustering measured for the SDSS sample. The small-scale clustering of our mock quasars is well-explained by central--satellite quasar pairs that reside in $M_{\rm h}\gt 10^{14}~\mathrm{M}_{\odot }\, h^{-1}$ dark matter haloes. For these pairs, satellite quasar luminosity is similar to that of central quasars. Our CLF models imply a relatively steep increase in the maximum satellite luminosity, $L^*_{\mathrm{sat}}$, in haloes of $M_{\rm h}\gt 10^{14}~\mathrm{M}_{\odot }\, h^{-1}$ with associated larger values of $L^*_{\mathrm{sat}}$ at higher redshift. This leads to increase in the satellite fraction that manifests itself in an enhanced clustering signal at ≲1 Mpc h−1. For the ongoing eBOSS-CORE sample, we predict ∼200–500 quasar pairs at z ∼ 1.5 (with $M_{\rm h} \gtrsim 10^{13}~\mathrm{M}_{\odot }\, h^{-1}$ and $M_{\rm bh} \gtrsim 10^{8}~\mathrm{M}_{\odot }\, h^{-1}$) at ∼25 kpc scales. Such a sample would be ≳ 10 times larger than current pair samples.

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Binary radial velocity measurements with space-based gravitational-wave detectors

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stz2077 ◽

2019 ◽

Vol 488 (4) ◽

pp. 5665-5670 ◽

Cited By ~ 7

Author(s):

Kaze W K Wong ◽

Vishal Baibhav ◽

Emanuele Berti

Keyword(s):

Black Hole ◽

Gravitational Wave ◽

Doppler Shift ◽

Globular Clusters ◽

Compact Object ◽

Massive Black Hole ◽

Massive Black Holes ◽

Doppler Shifts ◽

Future Space ◽

Electromagnetic Measurements

ABSTRACT Unlike traditional electromagnetic measurements, gravitational-wave observations are not affected by crowding and extinction. For this reason, compact object binaries orbiting around a massive black hole can be used as probes of the inner environment of the black hole in regions inaccessible to traditional astronomical measurements. The orbit of the binary’s barycentre around the massive black hole will cause a Doppler shift in the gravitational waveform, which is in principle measurable by future space-based gravitational-wave interferometers, such as the Laser Interferometer Space Antenna (LISA). We investigate the conditions under which these Doppler shifts are observable by LISA. Our results imply that Doppler shift observations can be used to study the central region of globular clusters in the Milky Way, as well the central environment of extragalactic massive black holes.

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