Plunging region emission in the X-ray binary MAXI J0637$-$430
Fuente:
arXiv
Saved in:
| Main Authors: | , , |
|---|---|
| Format: | Preprint |
| Published: |
2024
|
| Subjects: | |
| Online Access: | |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1866917700503076864 |
|---|---|
| author | Mummery, Andrew Jiang, Jiachen Fabian, Andrew |
| author_facet | Mummery, Andrew Jiang, Jiachen Fabian, Andrew |
| contents | On the second of November 2019 the black hole X-ray binary MAXI J0637$-$430 went into outburst, at the start of which it was observed in a thermal ``disc-dominated'' state. High photon energy (extending above 10 keV) observations taken by the NuSTAR telescope reveal that this thermal spectrum can not be fit by conventional two-component (disc plus corona) approaches which ignore disc emission sourced from within the plunging region of the black hole's spacetime. Instead, these models require a third ``additional'' thermal component to reproduce the data. Using new disc solutions which extend classical models into the plunging region we show that this ``additional'' thermal emission can be explained self-consistently with photons emitted from the accretion flow at radii within the innermost stable circular orbit of the black hole. This represents the second low mass X-ray binary, after MAXI J1820+070, with a detection of plunging region emission, suggesting that signatures of this highly relativistic region may well be widespread but not previously widely appreciated. To allow for a detection of the plunging region, the black hole in MAXI J0637$-$430 must be at most moderately spinning, and we constrain the spin to be $a_\bullet < 0.86$ at 99.9$\%$ confidence. We finish by discussing the observational requirements for the robust detection of this region. |
| format | Preprint |
| id |
arxiv_https___arxiv_org_abs_2406_14957 |
| institution | arXiv |
| publishDate | 2024 |
| record_format | arxiv |
| spellingShingle | Plunging region emission in the X-ray binary MAXI J0637$-$430 Mummery, Andrew Jiang, Jiachen Fabian, Andrew High Energy Astrophysical Phenomena General Relativity and Quantum Cosmology On the second of November 2019 the black hole X-ray binary MAXI J0637$-$430 went into outburst, at the start of which it was observed in a thermal ``disc-dominated'' state. High photon energy (extending above 10 keV) observations taken by the NuSTAR telescope reveal that this thermal spectrum can not be fit by conventional two-component (disc plus corona) approaches which ignore disc emission sourced from within the plunging region of the black hole's spacetime. Instead, these models require a third ``additional'' thermal component to reproduce the data. Using new disc solutions which extend classical models into the plunging region we show that this ``additional'' thermal emission can be explained self-consistently with photons emitted from the accretion flow at radii within the innermost stable circular orbit of the black hole. This represents the second low mass X-ray binary, after MAXI J1820+070, with a detection of plunging region emission, suggesting that signatures of this highly relativistic region may well be widespread but not previously widely appreciated. To allow for a detection of the plunging region, the black hole in MAXI J0637$-$430 must be at most moderately spinning, and we constrain the spin to be $a_\bullet < 0.86$ at 99.9$\%$ confidence. We finish by discussing the observational requirements for the robust detection of this region. |
| title | Plunging region emission in the X-ray binary MAXI J0637$-$430 |
| topic | High Energy Astrophysical Phenomena General Relativity and Quantum Cosmology |
| url | https://arxiv.org/abs/2406.14957 |