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 ðH Þ % 1500 km s À1 and undetected [O iii] 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 [R 4570 f ðFe ii 4570Þ= f ðH Þ % 1:59] is also typical of NLS1s. With a radio loudness RL ð f ;4:85 GHz =f ;B Þe1000 and radio power of P 4:85 GHz $ ð3:6 5:2Þ Â 10 26 W Hz À1 , it is the first bona fide, very radio loud NLS1. The inverted radio spectrum and very high brightness temperature (e10 13 K) derived from variation of the radio flux suggest the presence of a relativistic jet beaming toward the observer in this NLS1.
The photons released by the viscosity process in a disk with accretion rate exceeding the Eddington critical value will be trapped and restored as entropy in the accreting gas rather than being radiated from the disk surface, since the advection cooling dominates the di †usion cooling in such a Ñow. In this paper a self-similar solution of optically thick advection-dominated Ñow has been obtained. This kind of Ñow shows some interesting characteristics that di †er from both the optically thin advection-dominated disk and the standard disk. Such a Ñow is thermally stable. The Bernoulli number is not positive in a wide range of parameters unless the viscosity a is extremely small. The shape always stays slim and is independent of the accretion rateThe gas rotates with sub-Keplerian angular velocity (H/r B 1/J5). (for smaller viscosity). The luminosity of the disk weakly depends on the accretion rate, and ) B ) K /J5 the maximum luminosity is about 4.0 ] 1037 (ergs s~1) (less than the Eddington luminosity), (M/M _ ) although the accretion rate is super-Eddington. This provides a method for estimating the mass of a black hole. The validity of this solution has been tested and found to be suitable in most of the accretion disk (within the photon trapping radius). Its potential applications to the saturated accreting systems are pointed out.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.