2008/05/31 by Anna L. Watts, Alessandro Patruno, Michiel van der Klis · 27 citations
Physics and Astronomy · #Accretion (finance) #Astronomy and Astrophysical Research #Astrophysical Phenomena and Observations #Coherence (philosophical gambling strategy) #Millisecond #Millisecond pulsar #Oscillation (cell signaling) #Pulsar #Pulsars and Gravitational Waves Research #Pulse (music) #Thermonuclear fusion #astro-ph
paper · pdf · doi:10.1086/594365
published in The Astrophysical Journal 688(1), L37-L40 (IOP Publishing) · Improvements throughout, accepted for publication in ApJ Letters
arxiv created 2008/10/02 · openalex publication_date 2008/10/16 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
X-ray timing of the accretion-powered pulsations during the 2003 outburst of the accreting millisecond pulsar XTE J1814–338 has revealed variation in the pulse time of arrival residuals. These can be interpreted in several ways, including spin-down and wandering of the fuel impact point around the magnetic pole. In this Letter we show that the burst oscillations of this source are coherent with the persistent pulsations, to the level where they track all of the observed fluctuations. Only one burst, which occurs at the lowest accretion rates, shows a significant phase offset. We discuss what might lead to such rigid phase-locking between the modulations in the accretion and thermonuclear burst emission, and consider the implications for spin variation and the burst oscillation mechanism. Wandering of the fuel impact hot spot around a fixed magnetic pole seems the most likely cause for the accretion-powered pulse phase variations. This means that the burst asymmetry is coupled to the hot spot, not the magnetic pole. If premature ignition at this point (due to higher local temperatures) triggers a burning front that stalls before spreading over the entire surface, the resulting localized nuclear hot spot may explain the unusual burst and burst oscillation properties of this source.