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mungoid
2010-May-28, 04:34 AM
Is there somewhere where I can look to find a chart showing which lines in an emission spectrum indicate various elements.
for eg. if I'm looking at a line at around 800nm in the dark red part of the spectrun, which element does it represent?
Or is this just way too oversimplified?

mungoid
2010-May-28, 04:49 AM
I looked through previous posts but missed anything useful.
What I'm after is this:
http://i451.photobucket.com/albums/qq239/_Mungo/Astronomy/solarspectrum_noao.jpg
with an explanation of what each line is.

WayneFrancis
2010-May-28, 05:37 AM
Hyperphysics have a calculator some where I think.

http://hyperphysics.phy-astr.gsu.edu/hbase/tables/spectra.html#c1

01101001
2010-May-28, 05:59 AM
NIST Atomic Spectra Database (http://www.nist.gov/physlab/data/asd.cfm)


This database provides access and search capability for NIST critically evaluated data on atomic energy levels, wavelengths, and transition probabilities that are reasonably up-to-date. The Atomic Energy Levels Data Center and Data Center on Atomic Transition Probabilities and Line Shapes have carried out these critical compilations. Both Data Centers are located in the Physics Laboratory at the National Institute of Standards and Technology (NIST).

Contents of the NIST Atomic Spectra Database (http://www.nist.gov/physlab/data/asd_contents.cfm)


ASD contains data on about 950 spectra, with about 144,400 lines from 0.4 to 5,000,000 angstroms in wavelength, plus about 77,000 energy levels.

Just memorize them -- like the multiplication table.

mungoid
2010-May-29, 12:03 AM
thanks guys, very helpful.

Jeff Root
2010-May-29, 10:59 AM
Years ago in the U of M science and engineering library, I saw a
set of books of spectral line data, taking up 3-4 feet of shelf space,
but I think it only covered the X-ray part of the spectrum.

-- Jeff, in Minneapolis

JohnD
2010-May-29, 11:15 AM
Google is your friend. (but maybe I'm not)

Google for "Elements spectral lines" and first hit is this: http://www.colorado.edu/physics/2000/quantumzone/index.html
It has a demonstrator that shows the emission lines for many elements, that are the same as absortion lines, of course.
It doesn't list the frequencies, though, but implies that a list exists. (Doh! It must do! Else we know nothing about spectra.)

Or there's this one: http://astro.u-strasbg.fr/~koppen/discharge/
Does the same sort of thing, for more elements.

Or this one that does ALL the elements: http://jersey.uoregon.edu/vlab/elements/Elements.html in absorbtion AND emission

mungoid, people here are keen to help you, me included.
But you have to do your homework.
I'll leave it to you to find the actual frequencies.
Good luck!

John