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IC 4521


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The FIRST Bright Quasar Survey. II. 60 Nights and 1200 Spectra Later
We have used the Very Large Array (VLA) FIRST survey and the AutomatedPlate Measuring Facility (APM) catalog of the Palomar Observatory SkySurvey I (POSS-I) plates as the basis for constructing a newradio-selected sample of optically bright quasars. This is the firstradio-selected sample that is competitive in size with current opticallyselected quasar surveys. Using only two basic criteria, radio-opticalpositional coincidence and optical morphology, quasars and BL Lacobjects can be identified with 60% selection efficiency; the efficiencyincreases to 70% for objects fainter than 17 mag. We show that a moresophisticated selection scheme can predict with better than 85%reliability which candidates will turn out to be quasars. This paperpresents the second installment of the FIRST Bright Quasar Survey(FBQS), with a catalog of 636 quasars distributed over 2682deg2. The quasar sample is characterized and all spectra aredisplayed. The FBQS detects both radio-loud and radio-quiet quasars outto redshift z>3. We find a large population of objects ofintermediate radio loudness; there is no evidence in our sample for abimodal distribution of radio characteristics. The sample includes ~29broad absorption line quasars, both high and low ionization, and anumber of new objects with remarkable optical spectra.

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Takýmyýldýz:Coban
Sað Açýklýk:14h59m27.20s
Yükselim:+25°35'01.0"
Görünür Boyutlar:0.49′ × 0.339′

Kataloglar ve belirtme:
Özgün isimleri
ICIC 4521
HYPERLEDA-IPGC 53558

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