Кононов / 5
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The Instrument Response Function
Very simple concept: apply a delta function input to the system – what is the output (i.e. the system response)?
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h = response of the system to delta function: h(x) |
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x = time: h(t) |
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(t) - impulse response function (переходная функция) |
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x = coordinate: |
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(x) - point spread function – PSF (функция размытия точки) |
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x = frequency: |
h( ) |
( ) - frequency response function (передаточная функция) |
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IRF of two linear systems:
The output of a linear system is the convolution of the input and the impulse response (Green‘s function):
Example:
Molecular terms
Intensity & Spape of Spectral Lines
What is the strength of an absorption line?
Absorption: D = - lg T , T=I/I0
The Bouguer-Lambert-Beer Law:
A = ε∙C∙L
Коэффициенты Эйнштейна
The Interaction of Light and Matter I: A simple classical picture
A=1/ 0
The Einstein Coefficients [A. Einstein, Z. Phys.,18, 121 (1917)]
The Bouguer-Lambert-Beer Law
B
Absorption+desactivation: A
hν ∙[hν]∙[n1]∙B= [n2]∙A |
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d[hν] = [hν]∙ [n1]∙B∙ hν dt
d[hν] = [hν]∙ C∙B∙Na (1/1000)∙ hν ∙dx/c
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BNA h |
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[n1]+ [n2]=C |
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C [n1 ] B h |
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(A>> B hν [hν]) |
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[hν]+d[hν] |
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dx
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I I |
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