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Old 12-April-2008, 07:45 PM
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parejkoj parejkoj is offline
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Do you have a point to make with these posts, or an alternate theory to propose? This statement of yours,

Quote:
Originally Posted by William View Post
3) A better question than how are quasars fuelled, which assumes the quasar spectrum is generated by gas in falling to a traditional black hole, is what are the mechanisms and conditions that can generate the range of observed quasar spectrums.
seems to imply that you have another idea. If so, please state it. If not, do you have questions about the current theory of AGN fueling? Then please ask them, and I (and others) will try and answer.

You seem to be misunderstanding the Leighly paper. It is not discussing a "naked" AGN, but rather one with a very soft ionizing continuum:

Quote:
Originally Posted by Leighly et al., 2007
Can a soft SED by itself produce the observed unusual line emission? We explore this question using [the modeling package] Cloudy, and find that it can. A soft spectral energy distribution is stronger in the UV for a particular photoionizing flux than a hard SED; ... We conclude that the soft SED alone can qualitatively explain the line emission: high-ionization lines are weak because the continuum lacks photons to create the highly-ionized ions, semiforbidden and low-ionization collisionally-excited lines are absent because the gas is too cool to excite them, but lines excited by continuum pumping are strong because a soft SED continuum is stronger for a given photoionizing flux than a typical SED.
Do you actually have questions about the paper?
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