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Questions tagged [spectroscopy]

the practice of separating a signal by frequency (or sometimes energy or momentum) and analyzing the resulting spectrum.

Spectroscopy usually implies the separation is done physically using some kind of spectrometer, but with sufficient sampling it is possible to achieve comparable results with Fourier analysis.

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Do rainbows show spectral lines from the sun?

I'm aware of a similar question being asked in Do rainbow shows spectral lines?: The response to this question is that the body producing the light is not the water droplet that merely diffracts it but rather the Sun, which acts as a black body and…
Mario
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Experimental observation of matter/antimatter in the universe

Ordinary matter and antimatter have the same physical properties when it comes to, for example, spectroscopy. Hydrogen and antihydrogen atoms produce the same spectroscopy when excited, and adsorb the same frequencies. The charge does not make a…
Stefano Borini
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What actually is white light?

I was studying spectra and suddenly a question popped up relating to the absorption spectra. When we say that the electron absorbs certain wavelengths(photons) so we are implying that white light is a collection of infinite photons of many many…
chittaranjan rout
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How can the rest-frame spectrum of redshifted light be determined?

The redshift effect must work on all frequencies, so blue would be shifted down to some lower frequency, and ultra violet would be shifted down also, into the visible area. How would you know what part of the (pre-redshifted) spectrum you were…
peter
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Why do lines in atomic spectra have thickness? (Bohr's Model)

Consider the atomic spectrum (absorption) of hydrogen. The Bohr's model postulates that there are only certain fixed orbits allowed in the atom. An atom will only be excited to a higher orbit, if it is supplied with light that precisely matches…
Gerard
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Would the emission lines of a very distant galaxy show not many traces of heavier elements as that part of the universe was very young?

Would the emission lines of a very distant galaxy show not many traces of heavier elements as that part of universe was very young? Or was there enough time for an abundance of heavier elements?
Krešimir Bradvica
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Why does the Sun appear white through clouds?

Why does the Sun appear white through clouds? It seems there should not be any absorption of, say, the reddish component, as this would not produce a white colour. So what is going on? Am I right that clouds are white due to direct yellow light from…
Janko Bradvica
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What is the difference between the Balmer series of hydrogen and deuterium?

In my quantum mechanics textbook, it claims that the Balmer series between hydrogen and deuterium is different. However, I was under the impression that the Balmer series $$H_\alpha, H_\beta, H_\gamma$$ is related by the equation…
user2654176
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Why is sunlight spectrum continuous?

My teacher explained today that unlike the spectrum obtained by analyzing the sunlight, the spectra of atoms are not continuous. I have a question about this - the sunlight is emitted by the atoms of the elements composing the sun. So, spectrum…
Sensebe
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How can we detect antihydrogen?

From a mathematical standpoint (CPT symmetry) it is most probable that antihydrogen has the same spectra (absorption and emission) as hydrogen. The CERN confirmed this hypothesis to a high accuracy for the 1S-2S ray: ALPHA CERN 1S-2S antihydrogen…
athena
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Why is a plastic bag transparent in infrared light?

This is a classic trick to do with a IR camera: Bu why is the plastic bag transparent, while the glasses aren't? I've also heard that water is not transparent in IR light. What causes this phenomena?
Theodor
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Why can't I see the blue color scattered by the lower atmosphere of the earth?

I understand that the blue colour of the sky is because of the scattering of blue light by molecules in earth's atmosphere. The scattering appears to be happening from molecules that are far above in the earth's atmosphere. What about the scattering…
coder
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Does my green laser pointer emit three distinct frequencies, or is my measurement flawed?

I was playing around with a cheap diffraction grating and my set of laser pointers, and I noticed that while the red and the blue pointers produce a single point in the spectrum, my green laser produces three:                     I've googled for…
Roman Starkov
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What is the probability that a star of a given spectral type will have planets?

There is a lot of new data from the various extrasolar planet projects including NASA's Kepler mission on extra-solar planets. Based on our current data what is the probability that a star of each of the main spectral types (O, B, A, etc) will have…
dagorym
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What is the difference between Raman scattering and fluorescence?

What is the difference between Raman scattering and fluorescence? Both phenomena involve the emission of photons shifted in frequency relative to the incident light, because of some energetic transition between states that the system undergoes. As…
Deep Blue
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