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arXiv · 1301.3064

Flare-like variability of the Mg IIλ2800Å emission line in the gamma-ray blazar 3C 454.3

J. León-Tavares·V. Chavushyan·V. Patiño-Álvarez·E. Valtaoja·T. G. Arshakian·L. C. Popovic\altaffilmark·M. Tornikoski·A. Lobanov·A. Carramiñana·L. Carrasco·A. Lähteenmäki·.
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Abstract

We report the detection of a statistically significant flare-like event in the Mg IIλ2800Å emission line of 3C 454.3 during the outburst of autumn 2010. The highest levels of emission line flux recorded over the monitoring period (2008 - 2011) coincide with a superluminal jet component traversing through the radio core. This finding crucially links the broad-emission line fluctuations to the non-thermal continuum emission produced by relativistically moving material in the jet and hence to the presence of broad-line region clouds surrounding the radio core. If the radio core were located at several parsecs from the central black hole then our results would suggest the presence of broad-line region material outside the inner parsec where the canonical broad-line region is envisaged to be located. We briefly discuss the implications of broad-emission line material ionized by non-thermal continuum on the context of virial black hole mass estimates and gamma-ray production mechanisms.

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J. León-Tavares, V. Chavushyan, V. Patiño-Álvarez, E. Valtaoja, T. G. Arshakian, L. C. Popovic\altaffilmark, M. Tornikoski, A. Lobanov, A. Carramiñana, L. Carrasco, A. Lähteenmäki, .. 2013-01-14. Flare-like variability of the Mg IIλ2800Å emission line in the gamma-ray blazar 3C 454.3. https://doi.org/10.1088/2041-8205%2F763%2F2%2Fl36

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