X-ray spectral evolution in the ultraluminous X-ray source M33 X-8
نویسندگان
چکیده
منابع مشابه
The X - ray spectral evolution of the ultraluminous X - ray source Holmberg IX X - 1
We present a new analysis of X-ray spectra of the archetypal ultraluminous X-ray source (ULX) Holmberg IX X-1 obtained by the Swift, XMM-Newton and NuSTAR observatories. This ULX is a persistent source, with a typical luminosity of ∼10 erg s, that varied by a factor of 4 – 5 over eight years. We find that its spectra tend to evolve from relatively flat or two-component spectra in the medium ene...
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NGC 1313 X-2 is one of the brightest ultraluminous X-ray sources in the sky, at both X-ray and optical wavelengths; therefore, quite a few studies of available ESO VLT and HST data have appeared in the literature. Here, we present our analysis of VLT/FORS1 and HST/ACS photometric data, confirming the identification of the B ∼ 23 mag blue optical counterpart. We show that the system is part of a...
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We examined spectral evolution in ultraluminous X-ray sources (ULXs) with apparent luminosities of about 10 ergs s. Based on new results in this paper and those reported in the literature, two common spectral behaviors were found. Some ULXs in starburst galaxies have varying luminosity (L) but remain in the hard state with power-law spectra and a constant, hard photon index (Γ). Other ULXs, suc...
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ژورنال
عنوان ژورنال: Monthly Notices of the Royal Astronomical Society
سال: 2011
ISSN: 0035-8711
DOI: 10.1111/j.1365-2966.2011.19285.x