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paperstars
Sep13-09, 01:07 PM
Like the title says, I'm wondering what exactly is the definition for radio luminosity. A search on Google doesn't turn up with anything. I think it means the intensity of radio waves emitted, but I'm not sure. I'd rather you explain the term without using the word luminous or any variation of it because English is not my first language and it is not a word I'm too familiar with. (I keep confusing it with brightness.)

Also, I'm writing an essay on pulsars for school. I want to know if I can write surface magnetic flux density as B or must it be B_{surf}?

Thank you in advance.

bombadil
Sep15-09, 10:00 PM
Dear paperstars, good questions. The radio luminosity is the amount of electromagnetic energy an object (like a pulsar or a quasar) produces per second in the radio part of the spectrum.

Remember that electromagnetic waves include light (from red to violet in color) and x-rays and the radio waves your radio picks up. So when we say the radio part of the spectrum, we are talking about waves that have certain frequencies (usually from millions to billions of Hz). These radio waves carry energy that we measure with satellite dish looking things (i.e. radio telescopes), so we can measure how much radio energy per second a pulsar emits (its radio luminosity). (I'm skipping a few details here related to the ideas of radio flux.)

You can write the surface flux density however you want, as long as you are consistent and define what you mean.