Revealing the spectral state transition of the Clocked Burster, GS 1826-238 with NuSTAR StrayCats
arXiv:2212.05243 · doi:10.3847/1538-4357/acb689
Abstract
We present the long term analysis of GS 1826-238, a neutron star X-ray binary known as the "Clocked Burster", using data from NuSTAR StrayCats. StrayCats, a catalogue of NuSTAR stray light data, contains data from bright, off-axis X-ray sources that have not been focused by the NuSTAR optics. We obtained stray light observations of the source from 2014-2021, reduced and analyzed the data using nustar-gen-utils Python tools, demonstrating the transition of source from the "island" atoll state to a "banana" branch. We also present the lightcurve analysis of Type I X-Ray bursts from the Clocked Burster and show that the bursts from the banana/soft state are systematically shorter in durations than those from the island/hard state and have a higher burst fluence. From our analysis, we note an increase in mass accretion rate of the source, and a decrease in burst frequency with the transition.
References in corpus (5)
- Radius Constraints from Reflection Modeling of Cygnus X-2 with NuSTAR and NICER
- Deviations from the Flux-Recurrence Time Relationship in GS 1826-238: Potential Transient Spectral Changes
- StrayCats: A catalog of NuSTAR Stray Light Observations
- AstroSat view of `Clocked` burster GS 1826-238:broad-band spectral nature of persistent and burst emission during soft state
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