Recurring X-ray Outbursts in the Supernova Impostor SN~2010da in NGC~300

Abstract

We present new observations of the "supernova impostor" SN 2010da using the Chandra X-ray Observatory and the Hubble Space Telescope. During the initial 2010 outburst, the 0.3-10 keV luminosity was observed by Swift to be $\sim 5\times 10^{38}$ erg s${}^{-1}$ and faded by a factor of $\sim$25 in a four month period. Our two new Chandra observations show a factor of $\sim$10 increase in the 0.35-8 keV X-ray flux, from $\sim$4$\times 10^{36}$ erg s${}^{-1}$ to $4\times 10^{37}$ erg s${}^{-1}$ in $\sim$6 months, and the X-ray spectrum is consistent in both observations with a power law photon index of $\Gamma \sim 0$. We find evidence of X-ray spectral state changes: when SN 2010da is in a high-luminosity state, the X-ray spectrum is harder ($\Gamma \sim 0$) compared to the low-luminosity state ($\Gamma \sim 1.2\pm 0.8$). Using our Hubble observations, we fit the color magnitude diagram of the coeval stellar population to estimate a time since formation of the SN 2010da progenitor system of $\lesssim$5 Myr. Our observations are consistent with SN 2010da being a high-mass X-ray binary (HMXB) composed of a neutron star and a luminous blue variable-like companion, although we cannot rule out the possibility that SN 2010da is an unusually X-ray bright massive star. The $\lesssim$5 Myr age is consistent with the theoretically predicted delay time between the formation of a massive binary and the onset of the HMXB phase. It is possible that the initial 2010 outburst marked the beginning of X-ray production in the system, making SN 2010da possibly the first massive progenitor binary ever observed to evolve into an HMXB.

8 pages, accepted to MNRAS

References in corpus (20)

• Thermonuclear (type-I) X-ray bursts observed by the Rossi X-ray Timing Explorer
• The ACS Nearby Galaxy Survey Treasury
• The Evolution of Compact Binary Star Systems
• Catalogue of high-mass X-ray binaries in the Galaxy ($4^{th}$ edition)
• Evidence for the Strong Effect of Gas Removal on the Internal Dynamics of Young Stellar Clusters
• The Panchromatic Hubble Andromeda Treasury X. Ultraviolet to Infrared Photometry of 117 Million Equidistant Stars
• Black hole-like hysteresis and accretion states in neutron star low mass X-ray binaries
• Monitoring Supergiant Fast X-ray Transients with Swift. I. Behavior outside outbursts
• The ACS Nearby Galaxy Survey Treasury I. The Star Formation History of the M81 Outer Disk
• The influence of accretion geometry on the spectral evolution during thermonuclear (type-I) X-ray bursts
• Swift/XRT observes the fifth outburst of the periodic Supergiant Fast X-ray Transient IGR J11215-5952
• The NGC 300 Transient: An Alternative Method For Measuring Progenitor Masses
• An X-ray Survey of Wolf-Rayet Stars in the Magellanic Clouds. I. The Chandra ACIS Dataset
• Multiwavelength Observations of EXO 0748--676 -- II. Emission Line Behavior
• Monitoring Supergiant Fast X-ray Transients with Swift. Rise to the outburst in IGR J16479-4514
• Rapid spectral and timing variability of Be/X-ray binaries during type II outbursts
• X-ray emission from the giant magnetosphere of the magnetic O-type star NGC 1624-2
• Triggering Eruptive Mass Ejection in Luminous Blue Variables
• Expected number of supergiant fast X-ray transients in the Milky Way
• Chandra X-ray Sources in the LALA Cetus Field

Cited by in corpus (24)

• Discovery of pulsations from NGC 300 ULX1 and its fast period evolution
• The impact of companions on stellar evolution
• A Potential Cyclotron Resonant Scattering Feature in the ULX Pulsar NGC 300 ULX1 seen by NuSTAR and XMM-Newton
• No magnetars in ULXs
• Discovery of a red supergiant donor star in SN2010da/NGC 300 ULX-1
• NGC 300 ULX1: A test case for accretion torque theory
• Anti-glitches in the Ultraluminous Accreting Pulsar NGC 300 ULX-1 Observed with NICER
• Swift monitoring of M51: A 38-day super-orbital period for the pulsar ULX7 and a new transient ULX
• The Intermediate Luminosity Optical Transient SN 2010da: The Progenitor, Eruption and Aftermath of a Peculiar Supergiant High-mass X-ray Binary
• Clues to the Nature of SN 2009ip II: The Continuing Photometric and Spectroscopic Evolution to 1000 Days
• Formation Timescales for High-Mass X-ray Binaries in M33
• The connection between merging double compact objects and the Ultraluminous X-ray Sources
• Uncovering Red and Dusty Ultraluminous X-ray Sources with Spitzer
• No Strong Geometric Beaming in the Ultraluminous Neutron Star Binary NGC 300 ULX-1 (SN 2010da) from Swift and Gemini
• Rising from the Ashes: Mid-Infrared Re-Brightening of the Impostor SN 2010da in NGC 300
• Formation and Evolution of Ultraluminous X-ray Pulsar Binaries to Pulsar-Neutron Star and Pulsar-White Dwarf Systems
• CI Camelopardalis: The first sgB[e]-High Mass X-ray Binary Twenty Years on, a Supernova Imposter in our own Galaxy?
• A newly discovered double-double candidate microquasar in NGC 300
• A new sample of transient ultraluminous X-ray sources serendipitously discovered by Swift/XRT
• First Detection of Mid-Infrared Variability from an Ultraluminous X-Ray Source Holmberg II X-1
• Not an Oxymoron: Some X-ray Binary Pulsars with Enormous Spinup Rates Reveal Weak Magnetic Fields
• The X-ray Binary Population of the Nearby Dwarf Starburst Galaxy IC 10: Variable and Transient X-ray Sources
• Spectral Evolution of Ultraluminous X-ray Pulsar NGC 300 ULX-1
• Blue Supergiant X-ray Binaries in the Nearby Dwarf Galaxy IC 10