INTEGRAL observations of the Be/X-ray binary EXO 2030+375 during outburst

Abstract

We present a type-I outburst of the high-mass X-ray binary EXO 2030+375, detected during INTEGRAL's Performance and Verification Phase in December 2002 (on-source time about 10e+06 seconds). In addition, six more outbursts have been observed during INTEGRAL's Galactic Plane Scans. X-ray pulsations have been detected with a pulse period of 41.691798+-0.000016 s. The X-ray luminosity in the 5-300 keV energy range was 9.7*10e+36 erg/s, for a distance of 7.1 kpc. Two unusual features were found in the light curve, with an initial peak before the main outburst and another possible spike after the maximum. RXTE observations confirm only the existence of the initial spike. Although the initial peak appears to be a recurrent feature, the physical mechanisms producing it and the possible second spike are unknown. Moreover, a four-day delay between periastron passage and the peak of the outburst is observed. We present for the first time a 5-300 keV broad-band spectrum of this source. It can be modelled by the sum of a disk black body (kT_bb~8 keV) with either a power law model with Gamma=2.04+-0.11 keV or a Comptonized component (spherical geometry, kT_e=30 keV, tau=2.64, kT_W=1.5 keV).

arXiv comment10 pages, 11 figures, to be published in A&A

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Cited by in corpus (13)

• Advances in Understanding High-Mass X-ray Binaries with INTEGRAL and Future Directions
• Outbursts Large and Small from EXO 2030+375
• X-Ray and Optical Observations of A 0535+26
• Timing and Spectral properties of Be/X-ray pulsar EXO 2030+375 during a Type I outburst
• The pre-outburst flare of the A 0535+26 August/September 2005 outburst
• Rapid spectral and timing variability of Be/X-ray binaries during type II outbursts
• The appearance of magnetospheric instability in flaring activity at the onset of X-ray outbursts in A0535+26
• Integral/Ibis Census of the Sky Beyond 100 kev
• Possible regular phenomena in EXO 2030+375
• INTEGRAL observations of the Be/X-ray binary EXO 2030+375 during outburst
• Quasi-periodic flares in EXO 2030+375 observed with INTEGRAL
• Recent RXTE/ASM and ROTSEIIId Observations of EXO 2030+375
• INTEGRAL-ISGRI observations of the CygOB2 region: earching for hard X-ray point sources in a region containing several non-thermal emitting massive stars