massive black hole
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2021 ◽  
Author(s):  
Sangwha Yi

In the general relativity theory, we find the representation of the gravity field equation and solutions. We treat the representation of Schwarzschild solution, Reissner-Nodstrom solution, Kerr-Newman solution, Robertson -Walker solution. We found new general relativity theory (we call it Data General Relativity Theory; DGRT). We treat the data of Hawking radiation by Data general relativity theory. This theory has to apply black hole (specially, Primordial Massive Black Hole; PMBH) because black hole(PMBH) is an idealistic structure.


By quantizing space-time in such a way that I can calculate all of the constants of physics and derive and explain every equation therein. The magnetic field appears when the electric field seems to travel faster than c. The same way an “anti-gravity” perpendicular field appears, totally depended on relative velocities, since the electric and gravitational forces are made of the micro field lines and are different aspects of the same force [1]. The “gravitational” perpendicular force can be repellant, when masses travel in the same direction, (massive distant galaxies repel enlarging the universe, new current mass just being released) and it can be attractive (opposite spiral arms moving in opposite directions, combined with a super-massive black hole). The recent detection of gravity waves, is clear evidence for all of this since these waves need a perpendicular field, like electro-magnetic waves. The magnetic style of the perpendicular field, at extremely high can cause matter and dark to interact


2021 ◽  
Vol 923 (2) ◽  
pp. 139
Author(s):  
Fupeng Zhang ◽  
Xian Chen ◽  
Lijing Shao ◽  
Kohei Inayoshi

Abstract We study the stellar binary black holes (BBHs) inspiraling/merging in galactic nuclei based on our numerical method GNC. We find that 3%–40% of all newborn BBHs will finally merge due to various dynamical effects. In a five-year mission, up to 104, 105, and ∼100 of BBHs inspiraling/merging in galactic nuclei can be detected with signal-to-noise ration >8 in Advanced LIGO (aLIGO), Einstein/DECIGO, and TianQin/LISA/TaiJi, respectively. Roughly tens are detectable in both LISA/TaiJi/TianQin and aLIGO. These BBHs have two unique characteristics. (1) Significant eccentricities: 1%–3%, 2%–7%, or 30%–90% of them have e i > 0.1 when they enter into aLIGO, Einstein, or space observatories, respectively. Such high eccentricities provide a possible explanation for that of GW190521. Most highly eccentric BBHs are not detectable in LISA/Tianqin/TaiJi before entering into aLIGO/Einstein, as their strain becomes significant only at f GW ≳ 0.1 Hz. DECIGO becomes an ideal observatory to detect those events, as it can fully cover the rising phase. (2) Up to 2% of BBHs can inspiral/merge at distances ≲103 r SW from the massive black hole, with significant accelerations, such that the Doppler phase drift of ∼10–105 of them can be detected with signal-to-noise ratio >8 in space observatories. The energy density of the gravitational-wave backgrounds (GWBs) contributed by these BBHs deviates from the power-law slope of 2/3 at f GW ≲ 1 mHz. The high eccentricity, significant accelerations, and the different profile of the GWB of these sources make them distinguishable, and thus interesting for future gravitational-wave detections and tests of relativities.


2021 ◽  
Vol 923 (2) ◽  
pp. 146
Author(s):  
Alister W. Graham ◽  
Roberto Soria ◽  
Bogdan C. Ciambur ◽  
Benjamin L. Davis ◽  
Douglas A. Swartz

Abstract Galaxies can grow through their mutual gravitational attraction and subsequent union. While orbiting a regular high-surface-brightness galaxy, the body of a low-mass galaxy can be stripped away. However, the stellar heart of the infalling galaxy, if represented by a tightly bound nuclear star cluster, is more resilient. From archival Hubble Space Telescope images, we have discovered a red, tidally stretched star cluster positioned ∼5″ (∼400 pc in projection) from, and pointing toward the center of, the post-merger spiral galaxy NGC 4424. The star cluster, which we refer to as “Nikhuli,” has a near-infrared luminosity of (6.88 ± 1.85) × 106 L ⊙,F160W and likely represents the nucleus of a captured/wedded galaxy. Moreover, from our Chandra X-ray Observatory image, Nikhuli is seen to contain a high-energy X-ray point source, with L 0.5 − 8 keV = 6.31 − 3.77 + 7.50 × 10 38 erg s−1 (90% confidence). We argue that this is more likely to be an active massive black hole than an X-ray binary. Lacking an outward-pointing comet-like appearance, the stellar structure of Nikhuli favors infall rather than the ejection from a gravitational-wave recoil event. A minor merger with a low-mass early-type galaxy may have sown a massive black hole, aided an X-shaped pseudobulge, and be sewing a small bulge. The stellar mass and the velocity dispersion of NGC 4424 predict a central black hole of (0.6–1.0) × 105 M ⊙, similar to the expected intermediate-mass black hole in Nikhuli, and suggestive of a black hole supply mechanism for bulgeless late-type galaxies. We may potentially be witnessing black hole seeding by capture and sinking, with a nuclear star cluster the delivery vehicle.


Author(s):  
K. T. Voggel ◽  
A. C. Seth ◽  
H. Baumgardt ◽  
B. Husemann ◽  
N. Neumayer ◽  
...  

2021 ◽  
Vol 922 (2) ◽  
pp. 155
Author(s):  
Mallory Molina ◽  
Amy E. Reines ◽  
Colin J. Latimer ◽  
Vivienne Baldassare ◽  
Sheyda Salehirad

Abstract The massive black hole (BH) population in dwarf galaxies (M BH ≲ 105 M ⊙) can provide strong constraints on the origin of BH seeds. However, traditional optical searches for active galactic nuclei (AGNs) only reliably detect high-accretion, relatively high-mass BHs in dwarf galaxies with low amounts of star formation, leaving a large portion of the overall BH population in dwarf galaxies relatively unexplored. Here, we present a sample of 81 dwarf galaxies (M ⋆ ≤ 3 × 109 M ⊙) with detectable [Fe x]λ6374 coronal line emission indicative of accretion onto massive BHs, only two of which were previously identified as optical AGNs. We analyze optical spectroscopy from the Sloan Digital Sky Survey and find [Fe x]λ6374 luminosities in the range L [Fe x] ≈ 1036–1039 erg s−1, with a median value of 1.6 × 1038 erg s−1. The [Fe x] λ6374 luminosities are generally much too high to be produced by stellar sources, including luminous Type IIn supernovae (SNe). Moreover, based on known SNe rates, we expect at most eight Type IIn SNe in our sample. That said, the [Fe x]λ6374 luminosities are consistent with accretion onto massive BHs from AGNs or tidal disruption events (TDEs). We find additional indicators of BH accretion in some cases using other emission line diagnostics, optical variability, and X-ray and radio emission (or some combination of these). However, many of the galaxies in our sample only have evidence for a massive BH based on their [Fe x]λ6374 luminosities. This work highlights the power of coronal line emission to find BHs in dwarf galaxies missed by other selection techniques and to probe the BH population in bluer, lower-mass dwarf galaxies.


2021 ◽  
Vol 922 (2) ◽  
pp. L24
Author(s):  
Thomas Connor ◽  
Daniel Stern ◽  
Eduardo Bañados ◽  
Chiara Mazzucchelli

Abstract The z = 6.327 quasar SDSS J010013.02+280225.8 (hereafter J0100+2802) is believed to be powered by a black hole more massive than 1010 M ⊙, making it the most massive black hole known in the first billion years of the universe. However, recent high-resolution ALMA imaging shows four structures at the location of this quasar, potentially implying that it is lensed with a magnification of μ ∼ 450 and thus its black hole is significantly less massive. Furthermore, for the underlying distribution of magnifications of z ≳ 6 quasars to produce such an extreme value, theoretical models predict that a larger number of quasars in this epoch should be lensed, implying further overestimates of early black hole masses. To provide an independent constraint on the possibility that J0100+2802 is lensed, we reanalyzed archival XMM-Newton observations of the quasar and compared the expected ratios of X-ray luminosity to rest-frame UV and IR luminosities. For both cases, J0100+2802's X-ray flux is consistent with the no-lensing scenario; while this could be explained by J0100+2802 being X-ray faint, we find it does not have the X-ray or optical spectral features expected for an X-ray faint quasar. Finally, we compare the overall distribution of X-ray fluxes for known, typical z ≳ 6 quasars. We find a 3σ tension between the observed and predicted X-ray-to-UV flux ratios when adopting the magnification probability distribution required to produce a μ = 450 quasar.


2021 ◽  
Vol 922 (1) ◽  
pp. 74
Author(s):  
Jaroslav Haas ◽  
Ladislav Šubr

Abstract Stellar motions in the innermost parts of galactic nuclei, where the gravity of a supermassive black hole dominates, follow Keplerian ellipses to the first order of approximation. These orbits may be subject to periodic (Kozai–Lidov) oscillations of their orbital elements if some nonspherically distributed matter (e.g., a secondary massive black hole, coherent stellar subsystem, or large-scale gaseous structure) perturbs the gravity of the central supermassive black hole. These oscillations are, however, affected by the overall potential of the host nuclear star cluster. In this paper, we show that its influence strongly depends on the properties of the particular system, as well as the considered timescale. We demonstrate that for systems with astrophysically relevant parameters, the Kozai–Lidov oscillations of eccentricity can be enhanced by the extended potential of the cluster in terms of reaching significantly higher maximal values. In a more general statistical sense, the oscillations of eccentricity are typically damped. The efficiency of the damping, however, may be small to negligible for the suitable parameters of the system. This applies, in particular, in the case when the perturbing body is on an eccentric orbit.


2021 ◽  
Vol 2021 (11) ◽  
Author(s):  
John Joseph M. Carrasco ◽  
Ingrid A. Vazquez-Holm

Abstract The naive double-copy of (multi) loop amplitudes involving massive matter coupled to gauge theories will generically produce amplitudes in a gravitational theory that contains additional contributions from propagating antisymmetric tensor and dilaton states even at tree-level. We present a graph-based approach that combines the method of maximal cuts with double-copy construction to offer a systematic framework to isolate the pure Einstein-Hilbert gravitational contributions through loop level. Indeed this allows for a bootstrap of pure-gravitational results from the double-copy of massive scalar-QCD. We apply this to construct the novel result of the D-dimensional one-loop five-point QFT integrand relevant in the classical limit to generating observables associated with the radiative effects of massive black-hole scattering via pure Einstein-Hilbert gravity.


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