Holmberg IX: The Nearest Young Galaxy
نویسندگان
چکیده
منابع مشابه
The Broadband Spectral Variability of Holmberg IX X-1
We present results from four new broadband X-ray observations of the extreme ultraluminous X-ray source Holmberg IX X-1 ( > L 10 X 40 erg s ), performed by Suzaku and NuSTAR in coordination. Combined with the archival data, we now have broadband observations of this remarkable source from six separate epochs. Two of these new observations probe lower fluxes than seen previously, allowing us to ...
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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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We report the discovery of a 200 mHz quasi-periodic oscillation (QPO) in the X-ray emission from a bright ultra-luminous X-ray source (ULX) Holmberg IX X-1 using a long XMM-Newton observation. The QPO has a centroid at νQPO = 202.5 +4.9 −3.8 mHz, a coherence Q ≡ νQPO/∆νFWHM ≈ 9.3 and an amplitude (rms) of 6% in the 0.2 − 10 keV band. This is only the second detection of a QPO from an ULX, after...
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ژورنال
عنوان ژورنال: The Astrophysical Journal
سال: 2008
ISSN: 0004-637X,1538-4357
DOI: 10.1086/587548