2006/09/12 by R. H. D. Corbet, C. B. Markwardt, J. Tueller · 50 citations
Physics and Astronomy · #Astronomy and Astrophysical Research #Astrophysical Phenomena and Observations #Binary number #Binary star #Gamma-ray bursts and supernovae #Light curve #Modulation (music) #Orbital period #Period (music) #astro-ph
paper · pdf · doi:10.1086/509319
published in The Astrophysical Journal 655(1), 458-465 (IOP Publishing) · Accepted for publication in The Astrophysical Journal
arxiv created 2006/09/12 · openalex publication_date 2007/01/20 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
Observations of the high-mass X-ray binary 4U 2206+54 with the Swift Burst Alert Telescope (BAT) do not show modulation at the previously reported period of 9.6 days found from observations made with the Rossi X-Ray Timing Explorer ( RXTE ) All-Sky Monitor (ASM). Instead, the strongest peak in the power spectrum of the BAT light curve occurs at a period of 19.25 ± 0.08 days, twice the period found with the RXTE ASM. The maximum of the folded BAT light curve is also delayed compared to the maximum of the folded ASM light curve. The most recent ASM data folded on twice the 9.6 day period show similar morphology to the folded BAT light curve. This suggests that the apparent period doubling is a recent secular change rather than an energy-dependent effect. The 9.6 day period is thus not a permanent strong feature of the light curve. We suggest that the orbital period of 4U 2206+54 may be twice the previously proposed value.