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arXiv · 0804.1640

Detailed high-energy characteristics of AXP 4U 0142+61 - Multi-year observations with INTEGRAL, RXTE, XMM-Newton and ASCA

P. R. den Hartog·L. Kuiper·W. Hermsen·V. M. Kaspi·R. Dib·J. Knoedlseder·F. P. Gavriil
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Abstract

We present detailed spectral and temporal characteristics both in the hard X-ray (>10 keV) and soft X-ray (<10 keV) domains, obtained using data from INTEGRAL, XMM-Newton, ASCA and RXTE. The INTEGRAL time-averaged total spectrum shows a power-law like shape with photon index Gamma = 0.93 +/- 0.06. 4U 0142+61 is detected up to 229 keV and the flux between 20 keV and 229 keV is (15.01 +/- 0.82) x 10^(-11) erg/cm^2/s. Using simultaneously collected data with the spectrometer SPI of INTEGRAL the combined total spectrum yields the first evidence for a spectral break with a peak energy of 228 +65/-41 keV. There is no evidence for significant long-term time variability of the total emission. Pulsed emission is measured with ISGRI up to 160 keV. The 20-160 keV profile shows a broad double-peaked pulse with a 6.2 sigma detection significance. The total pulsed spectrum can be described with a very hard power-law shape with a photon index \Gamma = 0.40 +/- 0.15. We performed phase-resolved spectroscopy over the total high-energy band (2.8-300 keV) and identify at least three genuinely different pulse components with different spectra. The high level of consistency between the detailed results from the four missions is indicative for a remarkable stable geometry underlying the emission scenario.

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P. R. den Hartog, L. Kuiper, W. Hermsen, V. M. Kaspi, R. Dib, J. Knoedlseder, F. P. Gavriil. 2008-04-10. Detailed high-energy characteristics of AXP 4U 0142+61 - Multi-year observations with INTEGRAL, RXTE, XMM-Newton and ASCA. https://doi.org/10.1051/0004-6361:200809390

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