# Caught in the act: discovery of a physical quasar triplet

@article{Farina2013CaughtIT,
title={Caught in the act: discovery of a physical quasar triplet},
author={Emanuele Paolo Farina and Carmen Montuori and Roberto Decarli and Michele Fumagalli},
journal={Monthly Notices of the Royal Astronomical Society},
year={2013},
volume={431},
pages={1019-1025}
}
• E. Farina, +1 author M. Fumagalli
• Published 4 February 2013
• Physics
• Monthly Notices of the Royal Astronomical Society
We present the discovery of a triplet of quasars at z ≈ 1.51. The whole system is well accommodated within 25 arcsec (i.e. 200 kpc in projected distance). The velocity differences among the three objects (as measured through the broad Mg II emission line) are <1000 km s−1, suggesting that the quasars belong to the same physical structure. Broad-band near-infrared (NIR) images of the field do not reveal evidence of galaxies or galaxy clusters that could act as a gravitational lens, ruling out… Expand

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