What is Spectroscopy: Definition and 332 Discussions

Spectroscopy is the study of the interaction between matter and electromagnetic radiation as a function of the wavelength or frequency of the radiation. In simpler terms, spectroscopy is the precise study of color as generalized from visible light to all bands of the electromagnetic spectrum; indeed, historically, spectroscopy originated as the study of the wavelength dependence of the absorption by gas phase matter of visible light dispersed by a prism. Matter waves and acoustic waves can also be considered forms of radiative energy, and recently gravitational waves have been associated with a spectral signature in the context of the Laser Interferometer Gravitational-Wave Observatory (LIGO).
Spectroscopy, primarily in the electromagnetic spectrum, is a fundamental exploratory tool in the fields of physics, chemistry, and astronomy, allowing the composition, physical structure and electronic structure of matter to be investigated at the atomic, molecular and macro scale, and over astronomical distances. Important applications arise from biomedical spectroscopy in the areas of tissue analysis and medical imaging.

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  1. M

    Gamma Spectroscopy for Estimating Radiological Risk in Rocks

    Am currently doing an undergraduate project work on 'estimation of radiological risk pose by U-238, th-232 and K-40 in rock samples' . The instrument I'll use are NaI(TI) crystal for scintilation were the gamma rays from the source(my rock samples) interact with the crystal through photoelectric...
  2. H

    The axes in Raman spectroscopy

    What are the axes(horizontal & vertical axes) in a Raman spectrum?
  3. L

    About photoelectron spectroscopy, work function, ionization potential

    Dear all, I learn that photoelectron spectroscopy can measure the work function of solid semiconductors. However, some research papers reported it measured the ionization potential of solid semiconductor nanoparticle films. As we know there's obvious difference between the work function and...
  4. O

    Stimulated Raman Scattering Spectroscopy

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  5. L

    Absorption and Spectroscopy: Why increased counts at lower energies?

    Hi! In my lab class, we are using a photomultiplier to examine gamma ray emission lines and determine absorption coefficients of different radioactive materials. Homework Statement As we test for absorption (by layering on metals, incrementally increasing the thickness), we consider spectral...
  6. M

    Solving for R in Atomic Spectroscopy | Get Homework Help and Tips

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  7. stripes

    Some questions about spectroscopy

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  8. A

    Laser Induced Breakdown Spectroscopy

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  9. K

    Chemistry Spectroscopy (Molecular,Microwave)

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  10. fsonnichsen

    Excitation Effects for Fluorescence Spectroscopy

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  11. C

    Energy Reconstruction in Gamma Spectroscopy

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  12. Q

    IR and Raman Spectroscopy With Vibrational Modes

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  13. C

    Need help manipulating absorption spectroscopy data please

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  14. S

    Polarized Raman Spectroscopy: Understanding the Magic Angle

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  15. D

    Where to find an alpha radiation silicon detector? (alpha spectroscopy)

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  16. J

    Understanding molecular absorption of light (UV-Vis spectroscopy)

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  17. R

    Question about organic spectroscopy (IR)

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  18. S

    Radiation Detection / Spectroscopy Project

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  19. B

    What do the symbols \delta and \upsilon represent in IR spectroscopy?

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  20. W

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  21. D

    Photoelectron spectroscopy experiment

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  22. C

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  23. T

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  24. M

    Unlocking the Properties of Light: Geiger Spectroscopy and Wavelength Scanning

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  25. P

    Explaining linear spectroscopy from first principles

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  26. M

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  27. C

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  28. C

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  29. GreenAce92

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  30. A

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  31. R

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  32. D

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  33. F

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  34. P

    Transitions using Fluorescence Spectroscopy

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  35. S

    Master Spectroscopy with 13CH3OH: Correct Statements Explained

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  36. C

    Rotational and vibrational spectroscopy

    Hello there! Im studying microwave spectroscopy, and I'm stuck because I don't see why the spacing between rotational energy levels increases as J does. Can anyone explain please? Also, about IR, I see everywhere that the selction rule is Δv=±1. Correct me if I'm wrong but I'm guessing...
  37. C

    What is the point of ultrafast laser spectroscopy?

    Ultrafast laser spectroscopy, as I know, is used for the determination of femtosecond events in condensed phases. My question is, what applications do these discoveries have, or are they just for "research"?
  38. S

    Need help building a Near Infrared Spectroscopy Device

    Hi, I'm a computer scientist w/ very little hardware experience. I've been playing with the idea of using NIRS for a brain computer interface. The basic principle is pretty simple: You have a laser diode and a detector that is 2-3 cm away from the diode. Unfortunately I have almost no...
  39. C

    Spectroscopy how does it work?

    Okay, I'm havin trouble understanding the difference between NMR and spectrums. As far as I know: in NMR you excite a nuclei from one state to another. The frequency of the energy absorbed is what we measure. How is that related to normal spectrums and colour? For example, absorption of...
  40. A

    Eigenvalue Question (p2.14 in Quantum Chemistry and Spectroscopy)

    function: e^-(x^2/2) operator: d^2/dx^2 -x^2 The answer key says the function is an eigenfunction of the operator with an eigenvalue of -6. I can't figure out how to reach this conclusion. Also, Wolfram Alpha says d/dx(d/(dx)e^(-x^2/2)) = e^(-x^2/2) (x^2-1). Isn't this inconsistent with...
  41. O

    Questions on diatomic spectroscopy

    I've been looking at spectra from diatomic molecules. If I know the temperature of the material I'm looking at and I know which transition I want to look at how can I calculate what the observed flux (in Jansky) should be? Also, what can I calculate from observed FWHM? Thanks.
  42. G

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  43. B

    Raman spectroscopy help (simple)

    Homework Statement The Raman spectrum of ethene, obtained using 488.0nm radiation from a laser, shows an intense line at 540.0nm. Calculate the wavenumber for this vibration I know that you get stokes, anti-stokes and rayleigh scattering. Not sure how to calculate the wavenumber though ...
  44. V

    Astronomical spectroscopy and doppler shift.

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  45. B

    Quick rotational spectroscopy question(only need ideas/suggestions)

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  46. N

    Gamma ray spectroscopy of deuteron formation

    For my advanced physics lab course this semester, I recently conducted an experiment using a hyper-pure germanium detector to measure the energy of gamma rays released upon the formation of deuterium (DF). Essentially, I used a neutron source to bombard a hydrogen rich target (used both...
  47. B

    How Raman Spectroscopy works?

    Hello, I am currently in an analytical chemistry course where I am required to write a report on Raman Spectroscopy. The typical description of Raman Spectroscopy is the excitation of an electron to a "virtual" state, whereupon it can relax to a non zero vibrational level in its ground...
  48. S

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  49. J

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  50. O

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