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arXiv · 1205.3053

Luminous [O III] and [N II] from Tidally Disrupted Horizontal Branch Stars

Drew Clausen·Steinn Sigurdsson·Michael Eracleous·Jimmy A. Irwin
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Abstract

We model the emission lines generated in the photoionised debris of a tidally disrupted horizontal branch star. We find that at late times, the brightest optical emission lines are [N II] λλ6548,6583 and [O III] λλ4959,5007. Models of a red clump horizontal branch star undergoing mild disruption by a massive (50 -- 100 M_\sun) black hole yield an emission line spectrum that is in good agreement with that observed in the NGC 1399 globular cluster hosting the ultraluminous X-ray source CXOJ033831.8 - 352604. We make predictions for the UV emission line spectrum that can verify the tidal disruption scenario and constrain the mass of the BH.

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Drew Clausen, Steinn Sigurdsson, Michael Eracleous, Jimmy A. Irwin. 2012-05-14. Luminous [O III] and [N II] from Tidally Disrupted Horizontal Branch Stars. https://doi.org/10.1111/j.1365-2966.2012.21305.x

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