Context. IGRJ09026-4812 was discovered by INTEGRAL in 2006 as a new hard X-ray source. Thereafter, an observation with Chandra pinpointed a single X-ray source within the ISGRI error circle, showing a hard spectrum, and improving its high-energy localisation to a subarcsecond accuracy. Thus, the X-ray source was associated with the infrared counterpart 2MASSJ09023731-4813339 whose photometry indicated a highly reddened source. The high-energy properties and the counterpart photometry suggested a high-mass X-ray binary with a main sequence companion star located 6.3-8.1kpc away and with a 0.3-10keV luminosity of .Aims. New optical and infrared observations were needed to confirm the counterpart and to reveal the nature of IGRJ09026-4812. Methods. We performed optical and near infrared observations on the counterpart 2MASSJ09023731-4813339 with the ESO/NTT telescope on March 2007. We carried out photometry and spectroscopy in near infrared wavelengths and photometry in optical wavelengths. Results. The accurate astrometry at both optical and near infrared wavelengths confirmed 2MASSJ09023731-4813339 as the counterpart of IGRJ09026-4812. However, the near infrared images show that the source is extended, thus excluding the possibility of a Galactic compact source. The source spectrum shows three main emission lines identified as the HeI line, and the HIPaand Palines, typical of galaxies with an active galactic nucleus. The broadness of these lines reached values as large as 4000km,suggesting a type1 Seyfert galaxy. The redshift of the source is .Thus, the near infrared photometry and spectroscopy allowed us to classify IGRJ09026-4812 as a type1 Seyfert galaxy. Key words: galaxies: Seyfert - infrared: galaxies - X-rays: individual: IGRJ09026-4812
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