Galaxy Zoo Starburst Talk


  • fatha731 by fatha731

    Now here's something I haven't seen. As you can see on top of the spectrum it is noted that it is a QSO and AGN BROADLINE. But aren't QSOs AGNs? Or better, aren't AGNs caused by QSOs in the galaxy?

    enter image description here


  • JeanTate by JeanTate

    There's a lot of confusion over the terms "quasar", "QSO", and "AGN".

    In SDSS (official site), "quasar" is not used (or if it is, it's a synonym for QSO), and QSO is a kind of AGN; specifically, a QSO is an AGN whose intrinsic (absolute) luminosity is greater than some threshold. I did read up on this once; from memory, it's the i-band (our frame), and -21, with something close to 737 cosmology (I don't recall if they correct for galactic extinction, or apply some kind of K correction).