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Related papers: Microlensing Black Hole Shadows

200 papers

The black hole in the center of the Galaxy, associated with the compact source Sagittarius A* (Sgr A*), is predicted to cast a shadow upon the emission of the surrounding plasma flow, which encodes the influence of general relativity in the…

The quantum-corrected black hole model demonstrates significant potential in the study of gravitational lensing effects. By incorporating quantum effects, this model addresses the singularity problem in classical black holes. In this paper,…

General Relativity and Quantum Cosmology · Physics 2025-03-12 Lai Zhao , Meirong Tang , Zhaoyi Xu

We study, for the first time, the shadow of the supermassive black hole Sgr A$^{*}$ at the center of the Milky Way in dark matter halos. For the Cold Dark Matter and Scalar Field Dark Matter models considered in this work, the apparent…

General Relativity and Quantum Cosmology · Physics 2018-07-25 Xian Hou , Zhaoyi Xu , Ming Zhou , Jiancheng Wang

Accreting black holes tend to display a characteristic dark central region called the black-hole shadow, which depends only on spacetime/observer geometry and which conveys information about the black hole's mass and spin. Conversely, the…

High Energy Astrophysical Phenomena · Physics 2020-11-10 Thomas Bronzwaer , Jordy Davelaar , Ziri Younsi , Monika Mościbrodzka , Héctor Olivares , Yosuke Mizuno , Jesse Vos , Heino Falcke

Simulated images of a black hole surrounded by optically thin emission typically display two main features: a central brightness depression and a narrow, bright "photon ring" consisting of strongly lensed images superposed on top of the…

High Energy Astrophysical Phenomena · Physics 2021-09-08 Andrew Chael , Michael D. Johnson , Alexandru Lupsasca

The Event Horizon Telescope (EHT) collaboration's image of the compact object at the galactic center is the first direct evidence of the supermassive black hole (BH) Sgr A$^*$. The shadow of Sgr A$^*$ has an angular diameter $d_{sh}= 48.7…

General Relativity and Quantum Cosmology · Physics 2023-02-24 Misba Afrin , Sunny Vagnozzi , Sushant G. Ghosh

We investigate Einstein-\AE ther gravity in light of the recent Event Horizon Telescope (EHT) observations of the M87*. The shape and size of the observed black hole shadow contains information of the geometry in its vicinity, and thus one…

General Relativity and Quantum Cosmology · Physics 2021-05-20 Mohsen Khodadi , Emmanuel N. Saridakis

The study focuses on the impact of microlensing in modern cosmology and introduces a new framework for the static spherically symmetrical wormhole in terms of the radial equation of state. Following a standard procedure, the study…

General Relativity and Quantum Cosmology · Physics 2024-09-18 Ke Gao , Lei-Hua Liu

The measurements of the possible gravitational microlensing events are analysed with a simple yet accurate disc--halo model of the Milky Way Galaxy. This comprises a luminous exponential disc embedded in a flattened dark matter halo with…

Astrophysics · Physics 2016-06-08 N. W. Evans , J. Jijina

Kerr black holes coupled to quantized bosonic fields display a special version of the Hawking effect, governed by the superradiance condition. This leads to rapid growth of boson cloud through spontaneous creation, leading to slowing down…

General Relativity and Quantum Cosmology · Physics 2020-02-27 Rittick Roy , Urjit A. Yajnik

While elementary particles are the favored candidate for the elusive dark matter, primordial black holes (PBHs) have also been considered to fill that role. Gravitational microlensing is a very well-suited tool to detect and measure the…

Cosmology and Nongalactic Astrophysics · Physics 2024-09-10 Sven Heydenreich , Evencio Mediavilla , Jorge Jiménez-Vicente , Héctor Vives-Arias , Jose A. Muñoz

In a recent work on rotating black hole shadows [Phys. Rev. D{\bf 101}, 084029 (2020)], we proposed a new approach for calculating size and shape of the shadows in terms of astrometrical observables with respect to finite-distance…

General Relativity and Quantum Cosmology · Physics 2020-08-11 Zhe Chang , Qing-Hua Zhu

We show how Event Horizon Telescope (EHT) observations of the supermassive object at the center of M87 can constrain deviations from General Relativity (GR) in a relatively model-independent way. We focus on the class of theories whose…

General Relativity and Quantum Cosmology · Physics 2020-08-26 Markus Rummel , C. P. Burgess

We present estimates for the number of supermassive black holes (SMBHs) for which the next-generation Event Horizon Telescope (ngEHT) can identify the black hole ``shadow,'' along with estimates for how many black hole masses and spins the…

The Event Horizon Telescope is a millimeter VLBI array that aims to take the first pictures of the black holes in the center of the Milky Way and of the M87 galaxy, with horizon scale resolution. Measurements of the shape and size of the…

High Energy Astrophysical Phenomena · Physics 2020-01-08 Dimitrios Psaltis

The capability of the Event Horizon Telescope (EHT) to image the nearest supermassive black hole candidates at horizon-scale resolutions offers a novel means to study gravity in its strongest regimes and to test different models for these…

We present the first Event Horizon Telescope (EHT) observations of Sagittarius A* (Sgr A$^*$), the Galactic center source associated with a supermassive black hole. These observations were conducted in 2017 using a global interferometric…

High Energy Astrophysical Phenomena · Physics 2023-11-17 The Event Horizon Telescope Collaboration

The detection of microlensing has opened the way for the development of new methods in galactic astronomy. This series of papers investigates what microlensing can teach us about the structure and shape of the dark halo. In this paper we…

There is an exciting prospect of obtaining the shadow of astrophysical black holes (BHs) in the near future with the Event Horizon Telescope. As a matter of principle, this justifies asking how much one can learn about the BH horizon itself…

General Relativity and Quantum Cosmology · Physics 2018-04-25 Pedro V. P. Cunha , Carlos A. R. Herdeiro , Maria J. Rodriguez

We discuss the potential of the gravitational microlensing method as a unique tool to detect unambiguous signals caused by intermediate-mass black holes in globular clusters. We select clusters near the line of sight to the Galactic Bulge…

Astrophysics of Galaxies · Physics 2016-06-15 N. Kains , D. M. Bramich , K. C. Sahu , A. Calamida