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arXiv · 1008.4156

RXJ 0921+4529: a binary quasar or gravitational lens?

L. Č. Popović·A. V. Moiseev·E. Mediavilla·P. Jovanović·D. Ilić·J. Kovačević·J. Muñoz
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Abstract

We report the new spectroscopic observations of the gravitational lens RXJ 021+4529 with the multi-mode focal reducer SCORPIO of the SAO RAS 6-m telescope. The new spectral observations were compared with the previously observed spectra of components A and B of RXJ 0921+4529, i.e. the same components observed in different epochs. We found a significant difference in the spectrum between the components that cannot be explained with microlensing and/or spectral variation. We conclude that RXJ 0921+4529 is a binary quasar system, where redshifts of quasars A and B are 1.6535 +/- 0.0005 and 1.6625 +/- 0.0015, respectively.

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L. Č. Popović, A. V. Moiseev, E. Mediavilla, P. Jovanović, D. Ilić, J. Kovačević, J. Muñoz. 2010-08-24. RXJ 0921+4529: a binary quasar or gravitational lens?. https://doi.org/10.1088/2041-8205%2F721%2F2%2Fl139

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