A multi-wavelength view of distinct accretion regimes in the pulsating ultraluminous X-ray source NGC 1313 X-2
| العنوان: | A multi-wavelength view of distinct accretion regimes in the pulsating ultraluminous X-ray source NGC 1313 X-2 |
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| المؤلفون: | R Sathyaprakash, T P Roberts, F Grisé, P Kaaret, E Ambrosi, C Done, J C Gladstone, J J E Kajava, R Soria, L Zampieri |
| المساهمون: | Agenzia Spaziale Italiana, Istituto Nazionale di Astrofisica, National Aeronautics and Space Administration (US) |
| المصدر: | Digital.CSIC. Repositorio Institucional del CSIC instname Monthly Notices of the Royal Astronomical Society, 2022, Vol.511(4), pp.5346-5362 [Peer Reviewed Journal] |
| بيانات النشر: | Oxford University Press (OUP), 2022. |
| سنة النشر: | 2022 |
| مصطلحات موضوعية: | High Energy Astrophysical Phenomena (astro-ph.HE), Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, neutron [Stars], Astronomy and Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Stars: neutron, X-rays: binaries, Space and Planetary Science, Astrophysics::Solar and Stellar Astrophysics, binaries [X-rays], Astrophysics::Earth and Planetary Astrophysics, Astrophysics - High Energy Astrophysical Phenomena, Accretion discs, Astrophysics::Galaxy Astrophysics |
| الوصف: | NGC 1313 X-2 is one of the few known pulsating ultraluminous X-ray sources (PULXs), and so is thought to contain a neutron star that accretes at highly super-Eddington rates. However, the physics of this accretion remains to be determined. Here, we report the results of two simultaneous XMM-Newton and HST observations of this PULX taken to observe two distinct X-ray behaviours as defined from its Swift light curve. We find that the X-ray spectrum of the PULX is best described by the hard ultraluminous regime during the observation taken in the lower flux, lower variability amplitude behaviour; its spectrum changes to a broadened disc during the higher flux, higher variability amplitude epoch. However, we see no accompanying changes in the optical/UV fluxes, with the only difference being a reduction in flux in the near-infrared (NIR) as the X-ray flux increased. We attempt to fit irradiation models to explain the UV/optical/IR fluxes but they fail to provide meaningful constraints. Instead, a physical model for the system leads us to conclude that the optical light is dominated by a companion O/B star, albeit with an IR excess that may be indicative of a jet. We discuss how these results may be consistent with the precession of the inner regions of the accretion disc leading to changes in the observed X-ray properties, but not the optical, and whether we should expect to observe reprocessed emission from ULXs. RS gratefully acknowledges the receipt of a studentship grant from the STFC ST/N50404X/1. TPR was funded as part of the STFC consolidated grant ST/K000861/1. RS is extremely grateful for the guidance provided by Andrew Dolphin on HST data analysis. [...] EA acknowledges funding from the Italian Space Agency, contract ASI/INAF n. I/004/11/4. LZ acknowledges financial support from the Italian Space Agency (ASI) and National Institute for Astrophysics (INAF) under agreements ASI-INAF I/037/12/0 and ASI-INAF n.2017-14-H.0 and from INAF ’Sostegno alla ricerca scientifica main streams dell’INAF’ Presidential Decree 43/2018. RS acknowledges grant number 12073029 from the National Science Foundation of China. |
| وصف الملف: | application/pdf |
| تدمد: | 1365-2966 0035-8711 |
| URL الوصول: | https://explore.openaire.eu/search/publication?articleId=doi_dedup___::a35144fddb584baad8a8fc0e606f4c51 https://doi.org/10.1093/mnras/stac402 |
| حقوق: | OPEN |
| رقم الأكسشن: | edsair.doi.dedup.....a35144fddb584baad8a8fc0e606f4c51 |
| قاعدة البيانات: | OpenAIRE |
| تدمد: | 13652966 00358711 |
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