2009/12/01 by Ya-Juan Lei, Wei Chen, Jin‐Lu Qu +7 · 9 citations
Earth and Planetary Sciences · Engineering · Physics and Astronomy · #Accretion (finance) #Accretion disc #Astronomy #Astrophysical Phenomena and Observations #Astrophysics #Binary number #Emission spectrum #High-pressure geophysics and materials #Luminosity #Mechanics and Biomechanics Studies #Neutron star #Optics #Phase (matter) #Physics #Pulse (music) #Spectral analysis #Spectral line #Spectroscopy #X-ray binary #astro-ph.HE
paper · pdf · doi:10.1088/0004-637x/707/2/1016
published in The Astrophysical Journal 707(2), 1016-1022 (IOP Publishing) · 18 pages, 8 figures, accepted by ApJ
openalex publication_date 2009/12/01 · arxiv created 2009/12/24 · arxiv updated 2015/05/14 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
The high-mass X-ray binary 4U 1901+03 is reported to have a pulse profile evolving with the X-ray luminosity and energy during its outburst in 2003 February–July: the pulse peak changed from double to single along with the decreasing luminosity. We have carried out a detailed analysis on the contemporary phase-resolved energy spectrum of 4U 1901+03 as observed by the Rossi X-ray Timing Explorer . We find that the spectra are phase dependent. At the beginning of the outburst, the maximum of the optical depth for Compton scattering is near the major phase peak. During the decay of the outburst, the optical depth has the maximum away from the main peak of the pulse profile. For each observation, Fe Kα emission line is detected in the phase-resolved spectra, and its flux is constant across the pulse phases. This suggests that the origin of the Fe emission is from the accretion disk, not the surface of the neutron star.