https://doi.org/10.1140/epjc/s10052-017-5014-3
Regular Article - Theoretical Physics
Observational properties of rigidly rotating dust configurations
1
Department of Physics, Nazarbayev University, 53 Kabanbay Batyr avenue, 010000, Astana, Kazakhstan
2
Center for Field Theory and Particle Physics and Department of Physics, Fudan University, 220 Handan Road, 200433, Shanghai, China
3
Theoretical Astrophysics, Eberhard-Karls Universität Tübingen, Auf der Morgenstelle 10, 72076, Tübingen, Germany
* e-mail: daniele.malafarina@nu.edu.kz
Received:
23
January
2017
Accepted:
23
June
2017
Published online:
11
July
2017
We study the observational properties of a class of exact solutions of Einstein’s field equations describing stationary, axially symmetric, rigidly rotating dust (i.e. non-interacting particles). We ask the question whether such solutions can describe astrophysical rotating dark matter clouds near the center of galaxies and we probe the possibility that they may constitute an alternative to supermassive black holes at the center of galaxies. We show that light emission from accretion disks made of ordinary baryonic matter in this space-time has several differences with respect to the emission of light from similar accretion disks around black holes. The shape of the iron K
line in the reflection spectrum of accretion disks can potentially distinguish this class of solutions from the Kerr metric, but this may not be possible with current X-ray missions.
© The Author(s), 2017
