SDSS J094857.3+002225: A Very Radio Loud, Narrow-Line Quasar with Relativistic Jets?

We report the identification of a very radio loud, narrow-line quasar, SDSS J094857.3+002225, discovered in the Sloan Digital Sky Survey (SDSS) early data release (EDR). With FWHM (Hβ) ≈ 1500 km s-1 and undetected [O III] λλ 4959, 5007 SDSS J094857.3+002225 is consistent with the conventional definition of narrow-line Seyfert 1 galaxies (NLS1s). Its strong optical Fe II emission [R4570 ≡ f(Fe II λ4570)/f(Hβ) ≈ 1.59] is also typical of NLS1s. With a radio loudness RL ≡ (fν,4.85 GHz/fν,B) ≳ 1000 and radio power of P4.85 GHz ~ (3.6-5.2) × 1026 W Hz-1, it is the first bona fide, very radio loud NLS1. The inverted radio spectrum and very high brightness temperature (≳1013 K) derived from variation of the radio flux suggest the presence of a relativistic jet beaming toward the observer in this NLS1.

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