Characterizing the Evolving X-Ray Spectral Features During a Superburst from 4U 1636-536

Abstract

Recent studies have shown that runaway thermonuclear burning of material accreted onto neutron stars, i.e. Type I X-ray bursts, may affect the accretion disk. We investigate this by performing a detailed time-resolved spectral analysis of the superburst from 4U 1636-536 observed in 2001 with the Rossi X-ray Timing Explorer. Superbursts are attributed to the thermonuclear burning of carbon, and are approximately 1000 times more energetic than the regular short Type I bursts. This allows us to study detailed spectra for over 11 ks, compared to at most 100 s for regular bursts. A feature is present in the superburst spectra around 6.4 keV that is well fit with an emission line and an absorption edge, suggestive of reflection of the superburst off the accretion disk. The line and edge parameters evolve over time: the edge energy decreases from 9.4 keV at the peak to 8.1 keV in the tail, and both features become weaker in the tail. This is only the second superburst for which this has been detected, and shows that this behavior is present even without strong radius expansion. Furthermore, we find the persistent flux to almost double during the superburst, and return to the pre-superburst level in the tail. The combination of reflection features and increased persistent emission indicates that the superburst had a strong impact on the inner accretion disk, and it emphasizes that X-ray bursts provide a unique probe of accretion physics.

11 pages, 4 figures, 2 tables. Submitted for publication in ApJ

References in corpus (46)

• On the Absorption of X-rays in the Interstellar Medium
• 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
• Relativistic X-ray Lines from the Inner Accretion Disks Around Black Holes
• Models for Type I X-Ray Bursts with Improved Nuclear Physics
• In-flight Performance of the High Energy X-ray Timing Experiment on the Rossi X-ray Timing Explorer
• A Remarkable Three Hour Thermonuclear Burst From 4U 1820-30
• Carbon Flashes in the Heavy Element Ocean on Accreting Neutron Stars
• Neutron star stiff equation of state derived from cooling phases of the X-ray burster 4U 1724-307
• Long Type I X-ray Bursts and Neutron Star Interior Physics
• Relativistic iron emission lines in neutron star low-mass X-ray binaries as probes of neutron star radii
• Evidence for accretion rate change during type I X-ray bursts
• X-ray bursting neutron star atmosphere models: spectra and color corrections
• Evidence for a Millisecond Pulsar in 4U 1636-53 During a Superburst
• X-ray bursts at extreme mass accretion rates from GX 17+2
• On the Amplitude of Burst Oscillations in 4U 1636-54: Evidence for Nuclear Powered Pulsars
• Possible Resonances in the 12C + 12C Fusion Rate and Superburst Ignition
• The Evolution of the Accretion Disk around 4U 1820-30 During a Superburst
• New class of low frequency QPOs: signature of nuclear burning or accretion disk instabilities?
• Constraints on the Neutron Star and Inner Accretion Flow in Serpens X-1 Using NuSTAR
• Evidence of a Broad Relativistic Iron Line from the Neutron Star Low-Mass X-ray Binary Serpens X-1
• What ignites on the neutron star of 4U 0614+091?
• Systematic Uncertainties in the Spectroscopic Measurements of Neutron-Star Masses and Radii from Thermonuclear X-ray Bursts. I. Apparent Radii
• 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
• Spectral Fits to the 1999 Aql X-1 Outburst Data
• Evidence of heavy-element ashes in thermonuclear X-ray bursts with photospheric superexpansion
• A bright thermonuclear X-ray burst simultaneously observed with Chandra and RXTE
• Relativistic Iron Line Emission from the Neutron Star Low-mass X-ray Binary 4U 1636-536
• Recurrent very-long type-I X-ray bursts in the low-mass X-ray binary 4U 1636-53
• The observers' view of (very) long X-ray bursts: they are super!
• Superburst Models for Neutron Stars with Hydrogen and Helium-Rich Atmospheres
• A non-PRE double-peaked burst from 4U 1636-536: evidence for burning front propagation
• Millihertz Oscillation Frequency Drift Predicts the Occurrence of Type I X-ray Bursts
• On the Dynamics of Suddenly Heated Accretion Disks around Neutron Stars
• Multi-Zone Models of Superbursts from Accreting Neutron Stars
• Achromatic late-time variability in thermonuclear X-ray bursts - an accretion disk disrupted by a nova-like shell?
• Type-I X-ray bursts reveal a fast co-evolving behavior of the corona in an X-ray binary
• The hard X-ray shortages prompted by the clock bursts in GS 1826--238
• A very rare triple-peaked type-I X-ray burst in the low-mass X-ray binary 4U 1636-53
• The hard X-ray behavior of Aql X-1 during type-I bursts
• Carbon Detonation and Shock-Triggered Helium Burning in Neutron Star Superbursts
• Coherent oscillations and the evolution of the emission area in the decaying phase of radius-expansion bursts from 4U 1636-53
• X-ray spectral and timing properties of the 2001 superburst of 4U 1636-536
• Photospheric radius expansion in superburst precursors from neutron stars

Cited by in corpus (32)

• The Multi-INstrument Burst ARchive (MINBAR)
• Testing wormhole solutions in extended gravity through the Poynting-Robertson effect
• General relativistic Poynting-Robertson effect to diagnose wormholes existence: static and spherically symmetric case
• Thermonuclear X-ray bursts
• Evidence for enhanced persistent emission during sub-Eddington thermonuclear bursts
• Accretion disks and coronae in the X-ray flashlight
• The influence of accretion geometry on the spectral evolution during thermonuclear (type-I) X-ray bursts
• Anisotropy of X-ray bursts from neutron stars with concave accretion disks
• Discovery of a Neutron Star Oscillation Mode During a Superburst
• X-ray Reflection and An Exceptionally Long Thermonuclear Helium Burst from IGR J17062-6143
• Urca cooling pairs in the neutron star ocean and their effect on superbursts
• X-Raying an Accretion Disk in Realtime: the Evolution of Ionized Reflection during a Superburst from 4U 1636-536
• Thermonuclear burst observations for model comparisons: a reference sample
• Probing the effects of a thermonuclear X-ray burst on the neutron star accretion flow with NuSTAR
• A NICER look at thermonuclear X-ray bursts from Aql X-1
• Simulating the Collapse of a Thick Accretion Disk due to a Type I X-ray Burst from a Neutron Star
• NICER Discovers Spectral Lines During Photospheric Radius Expansion Bursts from 4U 1820-30: Evidence for Burst-driven Winds
• A catalogue of unusually long thermonuclear bursts on neutron stars
• NICER observations of the evidence of Poynting-Robertson drag and disk reflection during type I X-ray bursts from 4U 1636$-$536
• Diagnosing the burst influence upon accretion in the clocked burster GS 1826--238
• Lagrangian formulation of the general relativistic Poynting-Robertson effect
• The three-dimensional general relativistic Poynting-Robertson effect I: radial radiation field
• The imprint of carbon combustion on a superburst from the accreting neutron star 4U 1636-536
• Evolution of accretion disc reflection spectra due to a Type I X-ray burst
• Evidence of spreading layer emission in thermonuclear superbursts
• Accretion disk signatures in Type I X-ray Bursts: prospects for future missions
• Timescales of the chaos onset in the general relativistic Poynting-Robertson effect
• Quenching and recovery of persistent X-ray emission during a superburst in 4U 1820$-$30
• Radiation Driven Warping of Accretion Discs Due to X-ray Bursts
• Impact of Accretion Assumptions on Pulse Profile Modelling of Superburst Oscillations in 4U 1636-536
• Thermonuclear Type-I X-ray Bursts and Burst Oscillations from the Eclipsing AMXP Swift J1749.4-2807
• Tracing the outburst decay of soft X-ray transients Aql X-1 and 4U 1608-52 with XSPECT