Many gravitational wave (GW) sources in the LISA band are expected to have non-negligible eccentricity. Furthermore, many of them can undergo acceleration because they reside presence a tertiary. Here we develop analytical and numerical methods quantify how compact binary's eccentricity enhances detection its peculiar acceleration. We show that general relativistic precession pattern disentangle acceleration-induced frequency shift from chirp-mass-induced GW template fitting, thus relaxing...

Extreme-mass-ratio inspiral (EMRI) is an important gravitational-wave (GW) source and it normally consists of one stellar-mass black hole (BH) whirling closely around a supermassive (SMBH). In this Letter, we demonstrate that the small body, in fact, could be BH binary (BHB). Previous numerical scatting experiments have shown SMBHs can tidally capture BHBs to bound orbits. Here investigate subsequent long-term evolution. We find those with semi-major axis $a\lesssim5\times10^{-3}$ AU...

Retrieving the mass of a gravitational-wave (GW) source is fundamental but difficult problem because degenerate with redshift. In astronomy, three types redshift exist, namely cosmological, Doppler, and gravitational redshift, latter two are normally too weak to affect observation. this Letter, we show that current astrophysical models allow binary black holes (BBHs) merge within $10$ Schwarzschild radii supermassive hole (SMBH). We find in case both Doppler significant, most extreme...

Many black holes (BHs) detected by the Laser Interferometer Gravitational-wave Observatory (LIGO) and Virgo detectors are multiple times more massive than those in X-ray binaries. One possibility is that some BBHs merge within a few Schwarzschild radii of supermassive hole (SMBH), such gravitational waves (GWs) highly redshifted, causing mass inferred from GW signals to appear higher real mass. The difficulty this scenario lies delivery BBH small distance SMBH. Here we revisit theoretical...

ABSTRACT We report a candidate centi-parsec supermassive black hole binary (SMBHB) in the radio-quiet quasar SDSS J0159+0105 at z = 0.217. With modified Lomb–Scargle code (GLSdeDRW) and auto-correlation analysis, we detect two significant (at P > 99%) periodic signals ∼741 day ∼1500 from 8.1 yr Catalina V -band light curve of this quasar. The period ratio, which is close to 1:2, typical system with mass ratio 0.05 < q 0.8 according recent numerical simulations. has spectroscopic...

Abstract Extreme-mass-ratio inspirals (EMRIs) are important targets for future space-borne gravitational-wave (GW) detectors, such as the Laser Interferometer Space Antenna (LISA). Recent works suggest that EMRIs may reside in a population of newly discovered X-ray transients called “quasiperiodic eruptions” (QPEs). Here, we follow this scenario and investigate whether LISA could detect QPEs. We consider two specific models, which QPEs made either stellar-mass objects moving on circular...

Gravitational lensing of gravitational waves (GWs) is a powerful probe the matter distribution in universe. Here we revisit wave-optics effects induced by dark (DM) halos on GW signals merging massive black hole binaries (MBHBs), and study possibility discerning these using Laser Interferometer Space Antenna (LISA). In particular, include low-mass range $\rm 10^5-10^8\, M_\odot$ since they are most numerous according to cold DM model. We simulate lensed corresponding wide impact parameters,...

The recent increasing interest in detecting gravitational waves (GWs) by lunar seismic measurement urges us to have a clear understanding of the response moon passing GWs. In this paper, we clarify relationship between two seemingly different functions which been derived previously using methods, one taking field-theory approach and other tidal force induced We revisit their derivation prove, both analytical arguments numerical calculations, that are equivalent. Their apparent difference can...

New concepts for observing the gravitational waves (GWs) using a detector on Moon, such as Lunar Gravitational-wave Antenna (LGWA), have gained increasing attention. By utilizing Moon giant antenna, LGWA is expected to detect GWs in frequency range from 1 millihertz (mHz) several hertz, with optimal sensitivity decihertz band. Despite debated formation and evolution channel of intermediate-mass black holes (IMBHs) masses $[10^2, 10^5]\ {\rm M_\odot}$, binary systems containing at least one...

ABSTRACT The kinetic energy of a star in orbit about supermassive black hole is significant fraction its rest mass when periapse comparable to tidal radius. Upon destruction, this extracted and injected into the stellar debris, half which becomes unbound from hole, with fastest material moving at <?CDATA $\sim 0.03c$?> . In paper, we present formalism for determining fate these debris streams (UDSs) as they depart interact surrounding gas. As density velocity varies along length UDS, find...

Abstract Gravitational waves (GWs) can be produced if a stellar compact object, such as black hole (BH) or neutron star, inspirals into an intermediate-massive of <?CDATA $({10}^{3}\sim {10}^{5}){M}_{\odot }$?> . Such system may in the center globular cluster nuclear star and is known intermediate- extreme-mass-ratio inspiral (IMRI EMRI). Motivated by recent suggestions that dark matter minispikes could form around IMBHs, we study effect dynamical friction against DM on merger rate...

The velocity of a gravitational wave (GW) source provides crucial information about its formation and evolution processes. Previous studies considered the Doppler effect on phase GWs as potential signature time-dependent source. However, shift only accounts for time component vector, in principle motion also affects spatial components. latter effect, known ``aberration'' light, is analyzed this paper applied to waveform modeling an accelerating We show that additional aberrational could be...

Dark sirens, i.e., gravitational-wave (GW) sources without electromagnetic counterparts, are new probes of the expansion universe. The efficacy this method relies on correctly localizing host galaxies. However, recent theoretical studies have shown that astrophysical environments could mislead spatial localization by distorting GW signals. It is unclear whether and to what degree incorrect localizations dark sirens would impair accuracy measurement cosmological parameters. To address issue,...

The existence of "S-stars" within a distance 1'' from Sgr A* contradicts our understanding star formation, due to 's forbiddingly violent environment. A suggested possibility is that they form far away and were brought in by some fast dynamical process, since are young. Nonetheless, all conjectured mechanisms either fail reproduce their eccentricities—without violating young age—or cannot explain the problem "inverse mass segregation": fact lighter stars (the S-stars) closer more massive...

Abstract Recent theoretical studies suggest that stellar-mass binary black holes (BBHs) would merge more efficiently due to the Kozai–Lidov (K–L) mechanism if these binaries form in vicinity of supermassive (SMBHs). Since SMBHs are likely rotating rapidly, we continue our earlier study on generalization K–L formalism include spin SMBH and evolution a nearby BBH. We find eccentricity orbital inclination BBH significantly affected, because (i) forces plane center-of-mass around precess (the...

Abstract Recent astrophysical models predict that stellar-mass binary black holes (BBHs) could form and coalesce within a few gravitational radii of supermassive hole (SMBH). Detecting the waves (GWs) from such systems requires numerical tools can track dynamics binaries while capturing all essential relativistic effects. This work develops upon our earlier study BBH moving along circular orbit in equatorial plane Kerr SMBH. Here we modify method to simulate falling toward SMBH parabolic...

The models currently used in the detection of gravitational waves (GWs) either do not consider a relative motion between center mass source and observer or usually only its effect on frequencies GWs. However, it is known for light that changes but also brightness source, latter which called ``beaming effect.'' We investigate such an GWs find observed amplitude GW signal, unlike behavior light, monotonic function velocity responds differently to two polarizations. attribute difference...

Abstract Liu and collaborators recently proposed an elliptical accretion disk model for tidal disruption events (TDEs). They showed that the disks of optical/UV TDEs are large highly eccentric suggested broad optical emission lines with complex diverse profiles originate in a cool random inclination orientation. In this paper, we calculate radiation efficiency investigate implications observations TDEs. We compile observational data peak bolometric luminosity total energy after brightness 18...

One of the main targets Laser Interferometer Space Antenna (LISA) is detection extreme mass-ratio inspirals (EMRIs) and extremely large (X-MRIs). Their orbits are expected to be highly eccentric relativistic when entering LISA band. Under these circumstances, inspiral time-scale given by Peters' formula loses precision shift last-stable orbit (LSO) caused massive black hole spin could influence event rates estimate. We re-derive EMRIs X-MRIs implementing two different versions a Kerr...

It is known that massive black holes (MBHs) of $10^{5-7}\,M_\odot$ could capture small compact objects to form extreme-mass-ratio inspirals (EMRIs). Such systems emit gravitational waves (GWs) in the band Laser Interferometer Space Antenna (LISA) and are ideal probes space-time geometry MBHs. Recently, we have shown MBHs also stellar-mass binary (about $10\,M_\odot$) binary-EMRIs (b-EMRIs) and, interestingly, a large fraction binaries coalesce due tidal perturbation by Here further show...

After the final stage of merger two black holes, ringdown signal takes an important role on providing information about gravitational dynamics in strong field. We introduce a novel time-domain (TD) approach, predicated $\mathcal{F}$-statistic, for analysis. This method diverges from traditional TD techniques that its parameter space remains constant irrespective number modes incorporated. feature is achieved by reconfiguring likelihood and analytically maximizing over extrinsic parameters...

Most gravitational wave (GW) sources are moving relative to us. This motion is often closely related the environment of source and can thus provide crucial information about formation its host. Recently, LIGO Virgo detected for first time subdominant modes GWs. We show that a center mass affect these modes, where effect proportional velocity source. The on GW in turn affects overall frequency GW, leading phase shift. study impact this LIGO/Virgo detections it detectable with high ratios...

Extreme-mass-ratio inspirals are important sources for space-borne gravitational-wave detectors. Such a source normally consists of stellar-mass black hole (BH) and Kerr supermassive BH (SMBH), but recent astrophysical models predict that the small body could also be binary (BBH). A BBH reaching several gravitational radii SMBH will induce rich observable signatures in waveform, current numerical tools insufficient to simulate such triple system while capturing essential relativistic...

Standard sirens - GW sources with an EM counterpart can be used to measure H_0 directly which should help ease the existing Hubble tension. However, if source has a relative velocity expanding universe on top of its motion due flow, relativistic redshift affects and apparent distance source, thus it needs corrected obtain accurate measurements. We study effect such GWs for in showing that total wave is equal product cosmological redshift. We, further, find changes by factor (1+z_rel)^2...