The G292.0+1.8 pulsar wind nebula in the mid-infraredD. A. Zyuzin1, 2, A. A. Danilenko1, S. V. Zharikov3, and Yu. A. Shibanov1
1 Ioffe Physical Technical Institute, Politekhnicheskaya 26, St. Petersburg, 194021, Russia
2 Academical Physical Techonological University, Khlopina 2-8, St. Petersburg, 194021, Russia
3 Observatorio Astronómico Nacional SPM, Instituto de Astronomía, UNAM, Ensenada, BC, Mexico
Received 21 August 2009 / Accepted 21 September 2009
Context. G292.0+1.8 is a Cas A-like supernova remnant that contains the young pulsar PSR J1124-5916 powering a compact torus-like pulsar wind nebula visible in X-rays. A likely counterpart to the nebula has been detected in the optical VRI bands.
Aims. To confirm the counterpart candidate nature, we examined archival mid-infrared data obtained with the Spitzer Space Telescope.
Methods. Broad-band images taken at 4.5, 8, 24, and 70 m were analyzed and compared with available optical and X-ray data.
Results. The extended counterpart candidate is firmly detected in the 4.5 and 8 m bands. It is brighter and more extended in the bands than in the optical, and its position and morphology agree well with the coordinates and morphology of the torus-like pulsar wind nebula in X-rays. The source is not visible in 24 and 70 m images, which are dominated by bright emission from the remnant shell and filaments. We compiled the infrared fluxes of the nebula, which probably contains a contribution from an unresolved pulsar in its center, with the optical and X-ray data. The resulting unabsorbed multiwavelength spectrum is described by power laws of significantly steeper slope in the infrared-optical than in X-rays, implying a double-knee spectral break between the optical and X-rays. The 24 and 70 m flux upper limits suggest a second break and a flatter spectrum at the long wavelength limit. These features are common to two other pulsar wind nebulae associated with the remnants B0540-69.3 and 3C 58 and observed in all three ranges.
Conclusions. The position, morphology, and spectral properties of the detected source allow us to confirm that it is the infrared-optical counterpart to both the pulsar and its wind nebula system in the G292.0+1.8 supernova remnant.
Key words: ISM: supernova remnants -- pulsars: individual: PSR J1124-5916 -- stars: winds, outflows -- infrared: general -- radiation mechanisms: non-thermal -- ISM: individual objects: G292.0+1.8
© ESO 2009