Shadow of quadrupole-deformed compact objects in a local dark matter shell

Abstract

This work investigates observational properties, namely the shadow and photon ring structure, of emission profiles originating near compact objects. In particular, we consider a distorted and deformed compact object characterised by two quadrupole parameters and surrounded by an optically thin and geometrically thin accretion disk with different emission profiles modelled by Johnson's Standard-Unbound (SU) distribution in the reference frame of the emitter. Under these assumptions, we produce the observed intensity profiles and shadow images for a face-on observer. Our results indicate that, due to the fact that modifications of the quadrupole parameters affect the radius of the innermost stable circular orbit (ISCO) and the unstable photon orbits on the equatorial plane, the observed shadow images and their properties are significantly influenced by the quadrupole parameters and emission profiles. Furthermore, we analyse the impact of the presence of a dark matter halo in the observational imprints considered and verify that both the increase in the matter contained in the halo or the decrease in the length-scale of the halo lead to an increase in the size of the observed shadow. Our results indicate potential degeneracies between the observational features of distorted and deformed compact objects with those of spherically symmetric blackholes, which could be assessed by a comparison with the current and future generation of optical experiments in gravitational physics.

References in corpus (32)

• First M87 Event Horizon Telescope Results. I. The Shadow of the Supermassive Black Hole
• First Sagittarius A* Event Horizon Telescope Results. I. The Shadow of the Supermassive Black Hole in the Center of the Milky Way
• First M87 Event Horizon Telescope Results. VI. The Shadow and Mass of the Central Black Hole
• First M87 Event Horizon Telescope Results. IV. Imaging the Central Supermassive Black Hole
• First M87 Event Horizon Telescope Results. V. Physical Origin of the Asymmetric Ring
• First M87 Event Horizon Telescope Results. II. Array and Instrumentation
• First M87 Event Horizon Telescope Results. III. Data Processing and Calibration
• First M87 Event Horizon Telescope Results. VIII. Magnetic Field Structure near The Event Horizon
• Black Hole Shadows, Photon Rings, and Lensing Rings
• First Sagittarius A* Event Horizon Telescope Results. V. Testing Astrophysical Models of the Galactic Center Black Hole
• First M87 Event Horizon Telescope Results. VII. Polarization of the Ring
• First Sagittarius A* Event Horizon Telescope Results. III: Imaging of the Galactic Center Supermassive Black Hole
• First Sagittarius A* Event Horizon Telescope Results. II. EHT and Multi-wavelength Observations, Data Processing, and Calibration
• First Sagittarius A* Event Horizon Telescope Results. IV. Variability, Morphology, and Black Hole Mass
• Shadow of a black hole surrounded by dark matter
• The Shadow of a Spherically Accreting Black Hole
• The Shape of the Black Hole Photon Ring: A Precise Test of Strong-Field General Relativity
• Shadows of boson and Proca stars with thin accretion disks
• Imaging compact boson stars with hot-spots and thin accretion disks
• Shadows and photon rings of regular black holes and geonic horizonless compact objects
• Images and photon ring signatures of thick disks around black holes
• Photon rings of spherically symmetric black holes and robust tests of non-Kerr metrics
• Observational properties of relativistic fluid spheres with thin accretion disks
• New light rings from multiple critical curves as observational signatures of black hole mimickers
• Optical appearance of black holes surrounded by a dark matter halo
• Observational imprints of gravastars from accretion disks and hot-spots
• Spherically symmetric vacuum solutions in 1-Parameter New General Relativity and their phenomenology
• Probing Quadratic Gravity with the Event Horizon Telescope
• Black Hole Shadow with Soft Hair
• Magnetized tori in the background of a deformed compact object
• Circular geodesics in a New Generalization of q-metric
• Dynamics of charged particles and quasi-periodic oscillations in the vicinity of a distorted, deformed compact object embedded in a uniform magnetic field