An ultrafast outflow in the black hole candidate MAXI J1810−222?
| Autor: | M Del Santo, C Pinto, A Marino, A D’Aì, P-O Petrucci, J Malzac, J Ferreira, F Pintore, S E Motta, T D Russell, A Segreto, A Sanna |
|---|---|
| Rok vydání: | 2023 |
| Předmět: | |
| Zdroj: | Monthly Notices of the Royal Astronomical Society: Letters. 523:L15-L20 |
| ISSN: | 1745-3933 1745-3925 |
| Popis: | The transient X-ray source MAXI J1810-222 was discovered in 2018 and has been active ever since. A long combined radio and X-ray monitoring campaign was performed with ATCA and Swift respectively. It has been proposed that MAXI J1810-222 is a relatively distant black hole X-ray binary, albeit showing a very peculiar outburst behaviour. Here, we report on the spectral study of this source making use of a large sample of NICER observations performed between 2019 February and 2020 September. We detected a strong spectral absorption feature at $\sim$1 keV, which we have characterised with a physical photoionisation model. Via a deep scan of the parameters space, we obtained evidence for a spectral-state dependent outflow, with mildly relativistic speeds. In particular, the soft and intermediate states point to a hot plasma outflowing at 0.05-0.15 $c$. This speeds rule-out thermal winds and, hence, they suggest that such outflows could be radiation pressure or (most likely) magnetically-driven winds. Our results are crucial to test current theoretical models of wind formation in X-ray binaries. 6 pages, 10 figures, accepted for publication in MNRAS Letter |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|