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arXiv · 1507.04517

Multiple AGN in the crowded field of the compact group SDSSJ0959+1259

Alessandra De Rosa·Stefano Bianchi·Tamara Bogdanovic·Roberto Decarli·Ruben Herrero-Illana·Bernd Husemann·Stefanie Komossa·Emma Kun·Nora Loiseau·Zsolt Paragi·Miguel Perez-Torres·Enrico Piconcelli·Kevin Schawinski·Cristian Vignali
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Abstract

We present a multi-wavelength study of a newly discovered compact group (CG), SDSS J0959+1259, based data from XMM-Newton, SDSS and the Calar Alto optical imager BUSCA. With a maximum velocity offset of 500 km s$^{-1}$, a mean redshift of 0.035, and a mean spatial extension of 480 kpc, this CG is exceptional in having the highest concentration of nuclear activity in the local Universe, established with a sensitivity limit L$_{X}>4\times $10$^{40}$ erg s$^{-1}$ in 2--10 keV band and R-band magnitude $M_R < -19$. The group is composed of two type-2 Seyferts, one type-1 Seyfert, two LINERs and three star forming galaxies. Given the high X-ray luminosity of LINERs which reaches $\sim 10^{41}$ erg s$^{-1}$, it is likely that they are also accretion driven, bringing the number of active nuclei in this group to to 5 out of 8 (AGN fraction of 60\%). The distorted shape of one member of the CG suggests that strong interactions are taking place among its galaxies through tidal forces. Therefore, this system represents a case study for physical mechanisms that trigger nuclear activity and star formation in CGs.

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Alessandra De Rosa, Stefano Bianchi, Tamara Bogdanovic, Roberto Decarli, Ruben Herrero-Illana, Bernd Husemann, Stefanie Komossa, Emma Kun, Nora Loiseau, Zsolt Paragi, Miguel Perez-Torres, Enrico Piconcelli, Kevin Schawinski, Cristian Vignali. 2015-07-19. Multiple AGN in the crowded field of the compact group SDSSJ0959+1259. https://doi.org/10.1093/mnras%2Fstv1623

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