On the nature of the hard X-ray source IGR J2018+4043
arXiv:astro-ph/0609676 · doi:10.1086/508327
Abstract
We found a very likely counterpart to the recently discovered hard X-ray source IGR J2018+4043 in the multi-wavelength observations of the source field. The source, originally discovered in the 20-40 keV band, is now confidently detected also in the 40-80 keV band, with a flux of (1.4 +/- 0.4) x 10(-11) erg cm(-2) s(-1). A 5 ks Swift observation of the IGR J2018+4043 field revealed a hard point-like source with the observed 0.5-10 keV flux of 3.4(+0.7)(-0.8) x 10(-12) erg cm(-2) s(-1) (90% confidence level) at alpha = 20h18m38.55s, delta = +40d41m00.4s (with a 4.2" uncertainty). The combined Swift-INTEGRAL spectrum can be described by an absorbed power-law model with photon index gamma = 1.3 +/- 0.2 and N_H = 6.1(+3.2)(-2.2) x 10(22) cm(-2). In archival optical and infrared data we found a slightly extended and highly absorbed object at the Swift source position. There is also an extended VLA 1.4 GHz source peaked at a beam-width distance from the optical and X-ray positions. The observed morphology and multiwavelength spectra of IGR J2018+4043 are consistent with those expected for an obscured accreting object, i.e. an AGN or a Galactic X-ray binary. The identification suggests possible connection of IGR J2018+4043 to the bright gamma-ray source GEV J2020+4023 (3EG J2020+4017) detected by COS B and CGRO EGRET in the gamma-Cygni SNR field.
arXiv comment5 pages, 3 figures, uses emulateapj style
References in corpus (12)
- Maps of Dust IR Emission for Use in Estimation of Reddening and CMBR Foregrounds
- ISGRI: the INTEGRAL Soft Gamma-Ray Imager
- The INTEGRAL/IBIS Scientific Data Analysis
- Measuring Galactic Extinction: A Test
- The optical/NIR counterpart of the INTEGRAL obscured source IGR J16318-4848 : a sgB[e] in a HMXB ?
- Simultaneous X-ray and optical observations of S5 0716+714 after the outburst of March 2004
- Identifications of Four INTEGRAL Sources in the Galactic Plane via Chandra Localizations
- Collapse of Neutron Stars to Black Holes in Binary Systems: A Model for Short Gamma Ray Bursts
- A multi-wavelength search for a counterpart of the unidentified gamma-ray source 3EG J2020+4017 (2CG078+2)
- Hard X-ray Emission Clumps in the gamma-Cygni Supernova Remnant: an INTEGRAL-ISGRI View
- Is the INTEGRAL/IBIS source IGR J17204-3554 a gamma-ray emitting galaxy hidden behind the molecular cloud NGC 6334 ?
- INTEGRAL detection of hard X-rays from NGC 6334: Nonthermal emission from colliding winds or an AGN?