Discovery of a z = 6.1 Radio-Loud Quasar in the NDWFS
نویسندگان
چکیده
From examination of only 4 deg of sky in the NOAO Deep Wide-Field Survey (NDWFS) region, we have identified the first radio-loud quasar at a redshift z > 6. The object, FIRST J1427385+331241, was discovered by matching the FLAMEX IR survey to FIRST survey radio sources with NDWFS counterparts. One candidate z > 6 quasar was found, and spectroscopy with the Keck II telescope confirmed its identification, yielding a redshift z = 6.12. The object is a Broad Absorption Line (BAL) quasar with an optical luminosity ofMB ∼ −26.9 and a radio-to-optical flux ratio ∼ 60. Two Mg II absorptions systems are present at redshifts of z = 2.18 and z = 2.20. We briefly discuss the implications of this discovery for the high-redshift quasar population.
منابع مشابه
Discovery of radio-loud quasars with z=4.72 and z=4.01
We report the discovery of two radio-loud quasars with redshifts greater than four; GB1428+4217 with z = 4.72 and GB1713+2148 with z = 4.01. This doubles the number of published radio-selected quasars with z > 4, bringing the total to 4. GB1428+4217 is the third most distant quasar known and the highest redshift radio and X-ray source currently known. It has a radio flux density at 5GHz of 259±...
متن کاملGb1508+5714: a Radio-loud Quasar with Z=4.30 and the Space Density of High Redshift, Radio{loud Quasars
We report the discovery of a radio loud quasar with a redshift of 4.30. This object, which is the rst radio selected quasar with a redshift greater than four, was discovered during an observational investigation into the evolution of the luminosity function of radio loud quasars. Here we describe results based on a sample of 300, at spectrum radio sources with S 5GHz >200mJy. In this study, rat...
متن کاملdiscovery of gamma - ray emission from a relativistic jet in the narrow - line Seyfert 1 quasar
We report the discovery by the Large Area Telescope (LAT) onboard the Fermi Gamma-ray Space Telescope of high-energy gamma-ray emission from the peculiar quasar PMN J0948+0022 (z = 0.585± 0.001). Contrary to the expectations, the optical spectrum of this quasar shows only narrow lines [FWHM(Hβ) ∼ 1500 km/s] and the typical characteristics of narrow-line Seyfert 1 type galaxies. However, the str...
متن کاملDiscovery of Newly Formed Broad Absorption Lines in a Radio-Loud Quasar
We report a serendipitous discovery of broad absorption lines that were newly formed in the spectrum of the high-redshift, luminous radio-loud quasar TEX 1726+344, in a time interval of only 12 years. This is the first quasar showing a transition from narrow absorption lines to broad absorption lines. It also becomes one of the few radio-loud broad absorption line quasars. The gas cloud respons...
متن کاملHidden Blazars and Emission Line Variability of High Redshift Quasars
El resumen será traducido al español por los editores. We have carried out a survey to search for hidden blazars in a sample of z∼2 radio-loud quasars. The idea is based on our prediction that we should be able to see large CIV line variability not associated with observed continuum variations or most other emission lines in every radio-loud quasar. Here we report the initial results including ...
متن کامل