Puzzling thermonuclear burst behaviour from the transient low-mass X-ray binary IGR J17473-2721

Abstract

We investigate the thermonuclear bursting behaviour of IGR J17473-2721, an X-ray transient that in 2008 underwent a six month long outburst, starting (unusually) with an X-ray burst. We detected a total of 57 thermonuclear bursts throughout the outburst with AGILE, Swift, RXTE, and INTEGRAL. The wide range of inferred accretion rates (between <1% and about 20% of the Eddington accretion rate m-dot_Edd) spanned during the outburst allows us to study changes in the nuclear burning processes and to identify up to seven different phases. The burst rate increased gradually with the accretion rate until it dropped (at a persistent flux corresponding to about 15% of m-dot_Edd) a few days before the outburst peak, after which bursts were not detected for a month. As the persistent emission subsequently decreased, the bursting activity resumed with a much lower rate than during the outburst rise. This hysteresis may arise from the thermal effect of the accretion on the surface nuclear burning processes, and the timescale is roughly consistent with that expected for the neutron star crust thermal response. On the other hand, an undetected superburst, occurring within a data gap near the outburst peak, could have produced a similar quenching of burst activity.

18 pages, 12 figures, 1 table, accepted for publication in MNRAS

References in corpus (47)

• The Swift X-ray Telescope
• The Burst Alert Telescope (BAT) on the Swift MIDEX Mission
• Towards a unified model for black hole X-ray binary jets
• ISGRI: the INTEGRAL Soft Gamma-Ray Imager
• Thermonuclear (type-I) X-ray bursts observed by the Rossi X-ray Timing Explorer
• First Results from the All-Sky Monitor on the Rossi X-ray Timing Explorer
• Calibration of the Rossi X-ray Timing Explorer Proportional Counter Array
• Photospheric radius expansion X-ray bursts as standard candles
• In-flight Performance of the High Energy X-ray Timing Experiment on the Rossi X-ray Timing Explorer
• A catalogue of low-mass X-ray binaries in the Galaxy, LMC, and SMC (Fourth edition)
• The INTEGRAL Science Data Centre (ISDC)
• Jet-dominated states: an alternative to advection across black hole event horizons in `quiescent' X-ray binaries
• Panchromatic study of GRB 060124: from precursor to afterglow
• A Remarkable Three Hour Thermonuclear Burst From 4U 1820-30
• Carbon Flashes in the Heavy Element Ocean on Accreting Neutron Stars
• Mapping crustal heating with the cooling lightcurves of quasi-persistent transients
• Heating in the Accreted Neutron Star Ocean: Implications for Superburst Ignition
• Long Type I X-ray Bursts and Neutron Star Interior Physics
• SuperAGILE: the hard X-ray Imager for the AGILE space mission
• Six years of BeppoSAX Wide Field Cameras observations of nine galactic type-I X-ray bursters
• Helium-rich thermonuclear bursts and the distance to the accretion-powered millisecond pulsar SAX J1808.4-3658
• On the peak radio and X-ray emission from neutron star and black hole candidate X-ray transients
• On the possibility of a helium white dwarf donor in the presumed ultracompact binary 2S 0918-549
• Models of Type I X-ray Bursts from GS 1826-24: A Probe of rp-Process Hydrogen Burning
• X-ray time variability across the atoll source states of 4U 1636--53
• The INTEGRAL Galactic bulge monitoring program: the first 1.5 years
• A half-a-day long thermonuclear X-ray burst from KS 1731-260
• Multi-Instrument X-ray Observations of Thermonuclear Bursts with Short Recurrence Times
• Eddington-limited X-ray Bursts as Distance Indicators. II. Possible Compositional Effects in Bursts from 4U 1636-536
• First superburst from a classical low-mass X-ray binary transient
• A superburst from 4U 1254-690
• The Thermal Evolution following a Superburst on an Accreting Neutron Star
• Intermediate long X-ray bursts from the ultra-compact binary source SLX 1737-282
• Eddington-limited X-ray Bursts as Distance Indicators. I. Systematic Trends and Spherical Symmetry in Bursts from 4U 1728-34
• The disc-jet coupling in the neutron star X-ray binary Aquila X-1
• The observers' view of (very) long X-ray bursts: they are super!
• Discovery of X-ray burst triplets in EXO 0748-676
• A four-hours long burst from Serpens X-1
• BeppoSAX-WFC monitoring of the Galactic Center region
• Restless quiescence: thermonuclear flashes between transient X-ray outbursts
• Deviations from the Flux-Recurrence Time Relationship in GS 1826-238: Potential Transient Spectral Changes
• IGR J17254-3257, a new bursting neutron star
• An XMM-Newton observation of the neutron star X-ray transient 2S 1803-245 in quiescence
• Type-I bursts within outbursts of IGR J17473-2721
• Monitoring the hard X-ray sky with SuperAGILE
• GRB 070724B: the first Gamma Ray Burst localized by SuperAGILE and its Swift X-ray Afterglow
• Outbursts from IGR J17473-2721

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• Black hole-like hysteresis and accretion states in neutron star low mass X-ray binaries
• The Multi-INstrument Burst ARchive (MINBAR)
• Accretion disks and coronae in the X-ray flashlight
• A Soft X-Ray Spectral Episode for the Clocked Burster, GS 1826-24 as Measured by Swift and NuSTAR
• Superexpansion as a possible probe of accretion in 4U 1820-30
• The discovery of the 528.6 Hz accreting millisecond X-ray pulsar MAXI J1816-195
• The Galactic LMXB Population and the Galactic Centre Region
• The Influence of Stellar Spin on Ignition of Thermonuclear Runaways
• Catalog of outbursts of neutron star LMXBs
• The 2008 outburst of IGR J17473--2721: evidence for a disk corona?
• A transition from mixed-fuel to pure-helium thermonuclear bursts in Terzan 5 X-3/Swift J174805.3-244637