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arXiv · 1901.09757

Time delay measurement of Mg II line in CTS C30.10 with SALT

Bozena Czerny·Aleksandra Olejak·Mateusz Ralowski·Szymon Kozlowski·Mary Loli Martinez Aldama·Michal Zajacek·Wojtek Pych·Krzysztof Hryniewicz·Grzegorz Pietrzynski·C. Sobrino Figaredo·Martin Haas·Justyna Sredzinska·Magdalena Krupa·Agnieszka Kurcz·Andrzej Udalski·Marek Gorski·Vladimir Karas·Swayamtrupta Panda·Marzena Sniegowska·Mohammad-Hassan Naddaf·Marek Sarna
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Abstract

We report 6 yr monitoring of a distant bright quasar CTS C30.10 (z = 0.90052) with the Southern African Large Telescope (SALT). We measured the rest-frame time-lag of $562\pm 2$ days between the continuum variations and the response of the Mg II emission line, using the Javelin approach. More conservative approach, based on five different methods, imply the time delay of $564^{+109}_{-71}$ days. This time delay, combined with other available measurements of Mg II line delay, mostly for lower redshift sources, shows that the Mg II line reverberation implies a radius-luminosity relation very similar to the one based on a more frequently studied H$\beta$ line.

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Bozena Czerny, Aleksandra Olejak, Mateusz Ralowski, Szymon Kozlowski, Mary Loli Martinez Aldama, Michal Zajacek, Wojtek Pych, Krzysztof Hryniewicz, Grzegorz Pietrzynski, C. Sobrino Figaredo, Martin Haas, Justyna Sredzinska, Magdalena Krupa, Agnieszka Kurcz, Andrzej Udalski, Marek Gorski, Vladimir Karas, Swayamtrupta Panda, Marzena Sniegowska, Mohammad-Hassan Naddaf, Marek Sarna. 2019-01-28. Time delay measurement of Mg II line in CTS C30.10 with SALT. https://doi.org/10.3847/1538-4357/ab2913

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