Determining parameters of Kerr black holes at finite distance by shadow observation
Fuente:
arXiv
Guardado en:
| Autores principales: | , |
|---|---|
| Formato: | Preprint |
| Publicado: |
2023
|
| Materias: | |
| Acceso en línea: | |
| Etiquetas: |
Agregar Etiqueta
Sin Etiquetas, Sea el primero en etiquetar este registro!
|
| _version_ | 1866916129278001152 |
|---|---|
| author | Hioki, Kenta Miyamoto, Umpei |
| author_facet | Hioki, Kenta Miyamoto, Umpei |
| contents | We propose a new method to determine the physical parameters of Kerr black holes (namely, specific angular momentum $a$, inclination angle $i$, and distance $D$ from an observer) only from the shadow's information such as the size and shape. Key points in our method are (i) to treat the distance as a free parameter, (ii) to expand the shadow's outline as a Fourier series, and (iii) to construct principal components from the Fourier coefficients. These points enable us to obtain a one-to-one mapping between three principal components, being observables characterizing the size and deviation of shadow's shape from a circular disk, and the values of three parameters ($D/M, a/M, i$), where $M$ is the mass of black hole. Our method is applicable to various type of black holes and even to ones with accretion disks. |
| format | Preprint |
| id |
arxiv_https___arxiv_org_abs_2311_16802 |
| institution | arXiv |
| publishDate | 2023 |
| record_format | arxiv |
| spellingShingle | Determining parameters of Kerr black holes at finite distance by shadow observation Hioki, Kenta Miyamoto, Umpei General Relativity and Quantum Cosmology High Energy Astrophysical Phenomena We propose a new method to determine the physical parameters of Kerr black holes (namely, specific angular momentum $a$, inclination angle $i$, and distance $D$ from an observer) only from the shadow's information such as the size and shape. Key points in our method are (i) to treat the distance as a free parameter, (ii) to expand the shadow's outline as a Fourier series, and (iii) to construct principal components from the Fourier coefficients. These points enable us to obtain a one-to-one mapping between three principal components, being observables characterizing the size and deviation of shadow's shape from a circular disk, and the values of three parameters ($D/M, a/M, i$), where $M$ is the mass of black hole. Our method is applicable to various type of black holes and even to ones with accretion disks. |
| title | Determining parameters of Kerr black holes at finite distance by shadow observation |
| topic | General Relativity and Quantum Cosmology High Energy Astrophysical Phenomena |
| url | https://arxiv.org/abs/2311.16802 |