Dual supermassive black holes (SMBHs) with kpc-scale separations are an expected consequence of galaxy mergers, yet surprisingly few dual SMBHs have been observed to date. I will describe the first systematic search for dual SMBHs. This search employs a combination of large spectroscopic surveys of galaxies, longslit spectroscopy, and X-ray and radio observations to identify dual SMBHs that power active galactic nuclei. I will present the first batch of dual SMBHs that have been discovered with these techniques. This systematic survey will enable us, for the first time, to assemble a large observational catalog of dual SMBHs, which will provide observational constraints on the galaxy merger rate, SMBH growth via gas accretion during mergers, and SMBH coalescence.
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