2010/07/21 by Roberto Decarli, Massimo Dotti, Carmen Montuori +5 · 2 citations
Physics and Astronomy · #Astronomy #Astrophysical Phenomena and Observations #Astrophysics #Binary number #Black hole (networking) #Emission spectrum #Galaxies: Formation, Evolution, Phenomena #Galaxy #Gamma-ray bursts and supernovae #Physics #Quasar #Redshift #Rest frame #Spectral line #Superposition principle #Telescope #astro-ph.CO
paper · pdf · doi:10.1088/2041-8205/720/1/l93
2 figures, 1 table. Accepted for publication in ApJ Letters
arxiv created 2010/07/21 · openalex publication_date 2010/08/13 · arxiv updated 2015/05/19 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We report the discovery of peculiar features in the optical spectrum of 4C+22.25, a flat spectrum radio quasar at z = 0.4183 observed in the Sloan Digital Sky Survey and in a dedicated spectroscopic follow-up from the Nordic Optical Telescope. The Hβ and Hα lines show broad profiles (FWHM ∼ 12,000 km s −1 ), faint fluxes, and extreme offsets (Δ v = 8700 ± 1300 km s −1 ) with respect to the narrow emission lines. These features show no significant variation in a time lag of ∼3.1 yr (rest frame). We rule out possible interpretations based on the superposition of two sources or on recoiling black holes, and discuss the virtues and limitations of a massive black hole binary scenario.