Suchy S.,University of California at San Diego |
Pottschmidt K.,University of Maryland Baltimore County |
Pottschmidt K.,NASA |
Rothschild R.E.,University of California at San Diego |
And 18 more authors.
Astrophysical Journal | Year: 2011
We present broadband analysis of the Be/X-ray transient 1A1118-61 by Suzaku at the peak of its third observed outburst in 2009 January and two weeks later when the source flux had decayed by an order of magnitude. The continuum was modeled with a cutoffpl model as well as a compTT model, with both cases requiring an additional blackbody component at lower energies. We confirm the detection of a cyclotron line at ∼55 keV and discuss the possibility of a first harmonic at ∼110 keV. Pulse profile comparisons show a change in the profile structure at lower energies, an indication for possible changes in the accretion geometry. Phase-resolved spectroscopy in the outburst data shows a change in the continuum throughout the pulse period. The decrease in the cyclotron resonance scattering feature centroid energy also indicates that the viewing angle on the accretion column is changing throughout the pulse period. © 2011. The American Astronomical Society. All rights reserved..