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arXiv · 1011.3365

The quasar SDSS J142507.32+323137.4 : dual AGNs?

Zhixin Peng·Yanmei Chen·Qiusheng Gu·Chen Hu
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Abstract

We analyze the optical spectrum of type 1 QSO SDSS J1425+3231. This ob- ject is interesting since its narrow emission lines such as [O III]λλ4959, 5007 are double- peaked, and the line structure can be modeled well by three Gaussian components: two components for the two peaks (we refer the peaks at low/high redshift as "the blue/red component") and another one for the line wing which has the same line center as that of the blue component, but ~ 3 times broader. The separation between the blue and red components is ~ 500 km/s with blue component ~ 2 times broader than the red one. The Hβ emission can be separated into four components: two for the double-peaked narrow line and two for the broad line which comes from the broad line region (BLRs). The black hole mass estimated from the broad Hβ emission line using the typical reverberation map- ping relation is 0.85 \times 108M\odot, which is consistent with that derived from parameters of [O III]λ 5007 of the blue component. We suggest this QSO might be a dual AGN system, the broad Hβ emission line is mainly contributed by the primary black hole (traced by the blue component) while the broad Hβ component of the secondary black hole (traced by the red component) is hard to be separated out considering a resolution of ~2000 of SDSS spectra or it is totally obscured by the dusty torus.

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Zhixin Peng, Yanmei Chen, Qiusheng Gu, Chen Hu. 2010-11-15. The quasar SDSS J142507.32+323137.4 : dual AGNs?. https://doi.org/10.1088/1674-4527%2F11%2F4%2F004

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