Chandra monitoring observations of the ultraluminous X-ray source NGC 5204 X-1

Abstract

We report the results of a 2-month campaign conducted with the Chandra X-ray observatory to monitor the ultraluminous X-ray source (ULX) NGC 5204 X-1. This was composed of a 50-ks observation, followed by ten 5-ks follow-ups spaced initially at ~ 3, then at ~ 10 day intervals. The ULX flux is seen to vary by factors ~ 5 on timescales of a few days, but no strong variability is seen on timescales shorter than an hour. There is no evidence for a periodic signal in the X-ray data. An examination of the X-ray colour variations over the period of the campaign shows the ULX emission consistently becomes spectrally harder as its flux increases. The X-ray spectrum from the 50-ks observation can be fitted by a number of disparate spectral models, all of which describe a smooth continuum with, unusually for a ULX, a broad emission feature evident at 0.96 keV. The spectral variations, both within the 50-ks observation and over the course of the whole campaign, can then be explained solely by variations in the continuum component. In the context of an optically-thick corona model (as found in other recent results for ULXs) the spectral variations can be explained by the heating of the corona as the luminosity of the ULX increases, consistent with the behaviour of at least one Galactic black hole system in the strongly-Comptonised very high state. We find no new evidence supporting the presence of an intermediate-mass black hole in this ULX.

arXiv commentAccepted for publication in MNRAS. 15 pages, 8 figures

References in corpus (73)

• On the Absorption of X-rays in the Interstellar Medium
• Ultraluminous X-Ray Sources in External Galaxies
• The formation of massive black holes through collision runaway in dense young star clusters
• High Mass X-ray Binaries as a Star Formation Rate Indicator in Distant Galaxies
• The Nature of Accreting Black Holes in Nearby Galaxy Nuclei
• The Nature of Ultra-Luminous Compact X-Ray Sources in Nearby Spiral Galaxies
• Measuring the broadband power spectra of active galactic nuclei with RXTE
• Super-Eddington Fluxes from Thin Accretion Disks?
• Intermediate-Mass Black Holes
• GRS 1915+105 and the Disc-Jet Coupling in Accreting Black Hole Systems
• Black Hole Winds
• The Ultra-Luminous X-ray Source Population from the Chandra Archive of Galaxies
• XMM-Newton observations of the brightest Ultraluminous X-ray sources
• Discovery of X-ray QPOs from an Ultra-luminous X-ray Source in M82: Evidence Against Beaming
• A ROSAT HRI survey of bright nearby galaxies
• Population X: Are the super-Eddington X-ray sources beamed jets in microblazars or intermediate mass black holes?
• A Catalog of Candidate Intermediate-luminosity X-ray Objects
• Slim Disk Model for Ultra-Luminous X-Ray Sources
• Ultra-luminous X-ray Sources in nearby galaxies from ROSAT HRI observations I. data analysis
• GRS 1915+105: The brightest Galactic black hole
• Stellar Mass Black Hole Binaries as ULXs
• Discovery of Spectral Transitions from Two Ultra-Luminous Compact X-Ray Sources in Ic342
• An optically thick inner corona geometry for the Very High State Galactic Black Hole XTE J1550-564
• Revealing a Cool Accretion Disk in the Ultraluminous X-ray Source M81 X-9 (Holmberg IX X-1): Evidence for an Intermediate Mass Black Hole
• Black Hole Mass of the Ultraluminous X-ray source M82 X-1
• The optical counterpart of an Ultra-luminous X-Ray Source in NGC 5204
• The star-forming environment of a ULX in NGC 4559: an optical study
• A 62 Day X-Ray Periodicity and an X-Ray Flare from the Ultraluminous X-Ray Source in M82
• Accretion Disk Spectra of the Ultra-luminous X-ray Sources in Nearby Spiral Galaxies and Galactic Superluminal Jet Sources
• XMM-Newton Observations of Ultraluminous X-Ray Sources in Nearby Galaxies
• The importance of discovering a 3:2 twin-peak QPO in a ULX or how to solve the puzzle of intermediate mass black holes
• The Lack of Very Ultraluminous X-ray Sources in Early-type Galaxies
• Probable intermediate mass black holes in NGC4559: XMM-Newton spectral and timing constraints
• Three-Layered Atmospheric Structure in Accretion Disks Around Stellar-Mass Black Holes
• On the weakness of disc models in bright ULXs
• Ultraluminous X-ray Sources and Star Formation
• A variable Quasi-Periodic Ocillation in M82 X-1. Timing and spectral analysis of XMM-Newton and RossiXTE observations
• Chandra observations of five ultraluminous X-ray sources in nearby galaxies
• A transition to a low/soft state in the ultra-luminous compact X-ray source Holmberg II X-1
• Another intermediate mass black hole in a starburst galaxy?: The luminous X-ray source in NGC 3628 reappears
• The Time-Variable Ultra-Luminous X-ray Sources of "The Antennae"
• XMM-Newton EPIC observations of the ultraluminous X-ray source NGC 5204 X-1
• Dynamics and Energetics of Turbulent, Magnetized Disk Accretion around Black Holes: a First-Principles Approach to Disk-Corona-Outflow Coupling
• A deep XMM-Newton observation of the ultraluminous X-ray source HoII X-1 : the case against a 1000 solar mass black hole
• The identification of an optical counterpart to the super-Eddington X-ray source, NGC 5204 X-1
• A Chandra Study of the Circinus Galaxy Point-Source Population
• The Luminous X-ray Source Population in M51 Observed with Chandra
• A Chandra View of The Morphological And Spectral Evolution of Supernova Remnant 1987A
• The Brightest Black Holes
• Is M82 X-1 Really An Intermediate-Mass Black Hole? X-ray Spectral and Timing Evidence
• An Observational Diagnostic for Ultraluminous X-Ray Sources
• The optical counterpart of the ultra-luminous x-ray source NGC 5204 X-1
• X-ray flares from the ultra-luminous X-ray source in NGC 5408
• Another Interpretation of the Power-law type Spectrum of an Ultraluminous Compact X-ray Source in IC 342
• Quasi Periodic Oscillations and Strongly Comptonized X-ray emission from Holmberg IX X-1
• The X-ray Properties of M101 ULX-1 = CXOKM101 J140332.74+542102
• A Radio Monitoring Survey of Ultra-Luminous X-Ray Sources
• An Ultra-luminous X-Ray Object with a 2 hour period in M51
• XMM-Newton view of the ultra-luminous X-ray sources in M51
• XMM-Newton Observations of the Ultraluminous Nuclear X-ray Source in M33
• The Orbital Period of the Ultraluminous X-ray Source in M82
• The XMM-Newton View of GRS1915+105
• M74 X-1 (CXOU J013651.1+154547): An Extremely Variable Ultraluminous X-Ray Source
• An XMM-Newton view of M101: I. The luminous X-ray source population
• On the Nature of the Bright Short-Period X-ray Source in the Circinus Galaxy Field
• The Diffuse Emission and a Variable ULX in the Elliptical Galaxy NGC 3379
• A Two Hour Quasi-Period in an Ultra-luminous X-Ray source in NGC628
• Revealing the Supernova Remnant Population of M33 with Chandra
• Multi-band study of NGC 7424 and its two newly-discovered ULXs
• The Unusual Spectrum of the Ultra Luminous X-ray Source, M82 X-1
• X-ray and Optical Eclipses in ULXs as Possible Indicators of Black Hole Mass
• On the nature of the ultraluminous X-ray transient in Cen~A (NGC 5128)
• The recurrent ultra-luminous X-ray transient NGC 253 ULX1

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• Long-Term Spectral Variations of Ultraluminous X-ray Sources in the Interacting Galaxy Systems M51 and NGC4490/85
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• Black Holes and Neutron Stars in Nearby Galaxies: Insights from NuSTAR
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• X-ray properties of two transient ULX candidates in galaxy NGC 7090
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• Deep $Chandra$ observations of the NGC 4472 globular cluster black hole XMMU 122939.7+075333: Short term variability from the first globular cluster black hole binary
• Detection of X-ray elongated emission from a ultraluminous X-ray source in the interacting pair of galaxies NGC 5953/5954
• The supercritical accretion disk in SS433 and ultraluminous X-ray sources
• Ultraluminous X-ray sources in the group-centric elliptical galaxy NGC 5813