相关论文: Electromagnetic Signatures of Dark Photon Superrad…

If even a relatively small number of black holes were created in the early universe, they will constitute an increasingly large fraction of the total energy density as space expands. It is thus well-motivated to consider scenarios in which…

The possibility of mining the rotational energy from black holes has far--reaching implications. Such energy extraction could occur even for isolated black holes, if hypothetical ultralight bosonic particles exist in Nature, leading to a…

We present fully relativistic predictions for the electromagnetic emission produced by accretion disks surrounding spinning and nonspinning supermassive binary black holes on the verge of merging. We use the code Bothros to post-process…

Ultralight bosons are a class of hypothetical particles that could potentially solve critical problems in fields ranging from cosmology to astrophysics and fundamental physics. If ultralight bosons exist, they form clouds around spinning…

We present general relativistic radiation MHD simulations of super-Eddington accretion on a $10M_\odot$ black hole. We consider a range of mass accretion rates, black hole spins, and magnetic field configurations. We compute the spectra and…

Ultra-light hidden-photon dark matter produces an oscillating electric field in the early Universe plasma, which in turn induces an electric current in its ionized component whose dissipation results in heat transfer from the dark matter to…

Rotating black holes are well known to amplify the perturbing bosonic fields in certain parameter spaces. This phenomenon is popularly known as superradiance. In addition to rotation in the spacetime, charge plays a crucial role in the…

Some black holes in X-ray binaries accrete at rates far above the Eddington limit. In this supercritical regime, photons are trapped in a radiation-dominated, geometrically thick disk. The innermost regions form a complex environment of…

The EDGES Collaboration has recently reported the detection of a stronger-than-expected absorption feature in the global 21-cm spectrum, centered at a frequency corresponding to a redshift of z ~ 17. This observation has been interpreted as…

We consider photon emission from a supercritical accretion disk in which photons in the inner regions are trapped and advected in towards the center. Such disks are believed to be present in failed supernovae and gamma-ray bursts, and…

The images of supermassive black holes captured by the Event Horizon Telescope (EHT) collaboration have allowed us to have access to the physical processes that occur in the vicinity of the event horizons of these objects. This has enabled…

One of the most pressing questions in cosmology is how the black holes (BHs) powering quasars at high redshift grow to supermassive scales within a billion years of the Big Bang. Here we show that sustained super-Eddington accretion can be…

Hidden sectors with light extra U(1) gauge bosons, so-called hidden photons, have recently attracted some attention because they are a common feature of physics beyond the Standard Model like string theory and supersymmetry and additionally…

Advancements of very long baseline interferometry (VLBI) have facilitated unprecedented probing of superradiant phenomena in the vicinities of supermassive black holes (SMBHs), establishing an ideal laboratory to detect ultralight bosons…

Aims: We investigate photon quenching in compact non-thermal sources. This involves photon-photon annihilation and lepton synchrotron radiation in a network that can become non-linear. As a result the gamma-ray luminosity of a source cannot…

Magnetic fields surrounding spinning black holes can confine radiation and trigger superradiant instabilities. To investigate this effect, we perform the first fully-consistent linear analysis of the Ernst spacetime, an exact solution of…

Gravitational wave observation has provided numerous insights into the merger of astrophysical black holes. In contrast to other violent events (e.g. supernovae), they are, however, not expected to lead to significant emissions of photons…

The supermassive black holes (SMBHs) observed at the centers of all massive galaxies are believed to have grown via luminous accretion during quasar phases in the distant past. The fraction of inflowing rest mass energy emitted as light,…

Photons propagating in a plasma acquire an effective mass $\mu$, which is given by the plasma frequency and which scales with the square root of the plasma density. As noted previously by Conlon and Herdeiro, for electron number densities…

In this paper, we investigate the overlapping of photon rings - higher-order images of a black hole's luminous environment, concentrated near the shadow boundary and expected to be resolved in future observations. We consider a broad class…