Related papers: Gravitational Waves from Coalescing Black Hole MAC…
We study black hole MACHO binary formation through three-body interactions in the early universe at $t\sim 10^{-5}$s. The probability distribution functions of the eccentricity and the semimajor axis of binaries as well as of the…
Nakamura, Sasaki, Tanaka, and Thorne have recently estimated the initial distribution of binary MACHOs in the galactic halo assuming that the MACHOs are primordial half solar mass black holes, and considered their coalescence as a possible…
We use data from the second science run of the LIGO gravitational-wave detectors to search for the gravitational waves from primordial black hole (PBH) binary coalescence with component masses in the range 0.2--$1.0 M_\odot$. The analysis…
We present the first search for gravitational waves from the coalescence of stellar mass and sub-solar mass black holes with masses between $20 - 100~\mathrm{M}_{\odot}$ and $0.01 - 1~\mathrm{M}_{\odot}~($10 - 10^3$~\mathrm{M}_{J})$,…
We present the first search for gravitational waves from sub-solar mass compact-binary mergers which allows for non-negligible orbital eccentricity. Sub-solar mass black holes are a signature of primordial origin black holes, which may be a…
We report the observation of a gravitational-wave signal produced by the coalescence of two stellar-mass black holes. The signal, GW151226, was observed by the twin detectors of the Laser Interferometer Gravitational-Wave Observatory (LIGO)…
The intensity of low frequency gravitational waves from black hole MACHO binaries is studied. First we estimate the gravitational wave background produced by black hole MACHO binaries in the Milky Way halo as well as the cosmological…
In a recent paper we have shown that a minimally coupled, self-interacting scalar field of mass $m$ can form black holes of mass $M=\sqrt{3}/(4m)$ (in Planck units). If dark matter is composed by axions, they can form miniclusters that for…
The Laser Interferometer Gravitational Wave Observatory (LIGO) is one of a new generation of detectors of gravitational radiation. The existence of gravitational radiation was first predicted by Einstein in 1916, however gravitational waves…
We present a search for gravitational waves from the coalescence of sub-solar mass black hole binaries using data from the first half of Advanced LIGO and Virgo's third observing run. The observation of a sub-solar mass black hole merger…
The first LIGO-Virgo detections have confirmed the existence of massive black holes (BHs), with mass $30-40$ M$_\odot$. Such BHs might originate from massive metal-poor stars ($Z<0.3$ Z$_\odot$) or from gravitational instabilities in the…
The coalescence of massive black hole binaries (with masses $10^4 - 10^7 M_{\odot}$) leads to gravitational wave emission that is detectable out to high redshifts ($z \sim 20$) with the forthcoming LISA observatory. We combine the…
The MACHO project is searching for dark matter in the form of massive compact halo objects (Machos), by monitoring the brightness of millions of stars in the Magellanic Clouds to search for gravitational microlensing events. Analysis of our…
The failure to find evidence for elementary particles that could serve as the constituents of dark matter brings to mind suggestions that dark matter might consist of massive compact objects (MACHOs). In particular, it has recently been…
The high sensitivity of upcoming space-based gravitational wave detectors suggests the possibility that if halo dark matter were composed of primordial black holes (PBHs) with mass between $10^{16}$ g and 10$^{20}$ g, the gravitational…
The comoving mass density of massive black hole (MBH) remnants from pre-galactic star formation could have been similar in magnitude to the mass-density of supermassive black holes (SMBHs) in the present-day universe. We show that the…
On August 14, 2017 at 10:30:43 UTC, the Advanced Virgo detector and the two Advanced LIGO detectors coherently observed a transient gravitational-wave signal produced by the coalescence of two stellar mass black holes, with a…
Gravitational wave echos from the coalescence of black hole binaries are often viewed as signals beyond general relativity or standard model. In this work, we show that these echos are inevitable in the black holes coalescence described by…
Black hole-like objects with mass greater than $10 M_{\odot}$, as discovered by gravitational antennas, can produce long time-scale (several years) gravitational microlensing effects. Considered separately, previous microlensing surveys…
Under the assumption that the Milky Way's dark halo consists of primordial black hole MACHOs (PBHMACHOs), the mass density of the halo can be measured by the low frequency gravitational waves ($10^{-3} Hz \siml \nu_{gw} \siml 10^{-1}$ Hz)…