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Yet another galaxy identification for an ultraluminous X-ray source

N. Masetti·L. Foschini·L. C. Ho·M. Dadina·G. Di Cocco·G. Malaguti·E. Palazzi
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Abstract

We report on the identification of the optical and infrared counterparts of the ultraluminous X-ray source (ULX) XMMU J121214.5+131248 (NGC4168-ULX1). The optical spectrum yields a redshift of z=0.217, which implies that the ULX is not associated with the nearby galaxy NGC 4168, but rather with a background object. Optical spectral line ratios and the spectral energy distribution constructed from the available data indicate that the source is likely a starburst nucleus.

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N. Masetti, L. Foschini, L. C. Ho, M. Dadina, G. Di Cocco, G. Malaguti, E. Palazzi. 2003-05-23. Yet another galaxy identification for an ultraluminous X-ray source. https://doi.org/10.1051/0004-6361%3A20030785

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