Please use this identifier to cite or link to this item:
http://hdl.handle.net/2289/7785| Title: | Super-Eddington accretion on to a stellar mass ultraluminous X-ray source NGC 4190 ULX1 |
| Authors: | Ghosh, Tanuman Rana, Vikram |
| Keywords: | accretion accretion discs X-rays: binaries X-rays: individual (NGC 4190 ULX1) |
| Issue Date: | Jun-2021 |
| Publisher: | Oxford University Press on behalf of the Royal Astronomical Society |
| Citation: | Monthly Notices of the Royal Astronomical Society, 2021, Vol. 504, p974–982 |
| Abstract: | We present the results of high-quality XMM-NEWTON observations of a ultraluminous X-ray source (ULX) in the galaxy NGC 4190. The detection of spectral cutoff in NGC 4190 ULX1 spectra rules out the interpretation of the ULX to be in a standard low/hard canonical accretion state. We report that the high quality EPIC spectra can be better described by broad thermal component, such as a slim disc. In addition we found long-term spectral and flux variability in the source using several XMM-NEWTON and Swift data. A clear anticorrelation between flux and power-law photon index is found which further confirms the unusual spectral state evolution of the ULX. Spectral properties of the ULX suggest that the source is in a broadened disc state with luminosities [≈(3 − 10) × 1039 erg s−1] falling in the ultraluminous regime. The positive luminosity–temperature relation further suggests that the multicolour disc model follows the L ∝ T4 relation that is expected for a blackbody disc emission from a constant area and the slim disc model seems to favour L ∝ T2 relation consistent with an advection-dominated disc emission. From the broadened disc-like spectral feature at such luminosity, we estimated the upper limit of the mass of the central compact object from the inner disc radius and found that the ULX hosts a stellar mass black hole. |
| Description: | Restricted Access. An open-access version is available at arXiv.org (one of the alternative locations) |
| URI: | http://hdl.handle.net/2289/7785 |
| ISSN: | 0035-8711 1365-2966 (Online) |
| Alternative Location: | https://ui.adsabs.harvard.edu/abs/2021MNRAS.504..974G/abstract https://arxiv.org/abs/2103.10265 https://doi.org/10.1093/mnras/stab774 |
| Copyright: | 2021 The Author(s) |
| Appears in Collections: | Research Papers (A&A) |
Files in This Item:
| File | Description | Size | Format | |
|---|---|---|---|---|
| 2021_MNRAS_V504, p974–982.pdf Restricted Access | Restricted Access | 918.16 kB | Adobe PDF | View/Open Request a copy |
Items in RRI Digital Repository are protected by copyright, with all rights reserved, unless otherwise indicated.