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avicenna
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How can we experimentally measure the wavelength of gamma-rays, say for about 0.7MeV?
Can it be done without gamma-ray spectrometry?
Can it be done without gamma-ray spectrometry?
What wavelength does one calculate from the stated energy?avicenna said:How can we experimentally measure the wavelength of gamma-rays, say for about 0.7MeV?
Can it be done without gamma-ray spectrometry?
I thought of Bragg diffraction, but 'measuring' the wavelength requires 'knowing' the distance between atoms in crystal. How does one 'know' or 'measure' the distance between atoms? X-ray diffraction.hutchphd said:I am confused by these answers. What then does Bragg diffraction of X-rays from a crystal measure?
Or atomic force microscopy, these days. By far less precise than x-ray diffraction of course.Astronuc said:How does one 'know' or 'measure' the distance between atoms? X-ray diffraction.
I thought about AFM, but wasn't sure. I'm curious about the resolution. I could not find a definitive statement, other than noise on the order of 10s of pm. A 1 MeV gamma ray has a wavelength of ~1.24 pm (~0.00124 nm), so diffraction methods are too coarse. Atomic radii of most atoms are on the order of 100 pm, and lattice constants slightly larger.mfb said:Or atomic force microscopy, . . .
You gain a lot from the angle. If you can determine the height of a layer to be e.g. 100 pm +- 3 pm your relative uncertainty on the wavelength from the lattice constant will just be 3%, even if you measure wavelengths below 10 pm because the diffraction angle is small. But, as V50 noted, you can also measure the mass of an atom and the mass of a macroscopic object.Astronuc said:I thought about AFM, but wasn't sure. I'm curious about the resolution. I could not find a definitive statement, other than noise on the order of 10s of pm. A 1 MeV gamma ray has a wavelength of ~1.24 pm (~0.00124 nm), so diffraction methods are too coarse. Atomic radii of most atoms are on the order of 100 pm, and lattice constants slightly larger.
The wavelength of gamma-rays can be measured using a technique called spectroscopy. This involves passing the gamma-rays through a diffraction grating, which separates the different wavelengths of light. The resulting spectrum can then be analyzed to determine the wavelength of the gamma-rays.
To measure the wavelength of gamma-rays, specialized equipment such as a gamma-ray spectrometer or a scintillation detector is required. These devices are designed to accurately detect and measure the energy of gamma-rays.
No, a ruler or measuring tape is not suitable for measuring the wavelength of gamma-rays. Gamma-rays have a very short wavelength, typically in the range of 0.01 to 10 nanometers, which is much smaller than the smallest markings on a ruler or measuring tape.
The accuracy of measuring the wavelength of gamma-rays depends on the precision of the equipment used. With advanced spectroscopic techniques, it is possible to measure the wavelength of gamma-rays with an accuracy of a few nanometers.
Measuring the wavelength of gamma-rays is crucial for understanding their properties and behavior. It allows scientists to identify the source and energy of gamma-rays, which can provide valuable information about the processes occurring in the universe, such as nuclear reactions and high-energy astrophysical phenomena.