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Can gamma ray frequencies be measured directly?

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I know there are ways to measure light frequencies directly using diffraction, etc, even for x-rays.

Is there a way to directly measure the frequency of gamma rays? Not using energy detectors and E=hf.

 

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21 minutes ago, avicenna said:

Not using energy detectors and E=hf.

Why is this not direct?

What do you mean by direct?

Frequency analysis of gamma rays is called gamma ray spectroscopy

https://en.wikipedia.org/wiki/Gamma_spectroscopy

Note gamma and X ray frequencie ranges sunstantially overlap.

The difference is the nature of source.

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2 hours ago, avicenna said:

I know there are ways to measure light frequencies directly using diffraction, etc, even for x-rays.

Is there a way to directly measure the frequency of gamma rays? Not using energy detectors and E=hf.

You can do diffraction with x-rays and gammas. Crystal lattices have spacing that is appropriate for this. X-ray crystallography would work with some gammas

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I'm guessing that "direct" measurement of frequencies means counting the number of times it goes up and down in a second.

As far as I know you can't do that much beyond the microwave regions (maybe mm wave?).

I'm not sure if tehOP counts this as "direct" or not.

https://en.wikipedia.org/wiki/Frequency_comb#Applications

 

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4 hours ago, studiot said:

Why is this not direct?

What do you mean by direct?

Frequency analysis of gamma rays is called gamma ray spectroscopy

https://en.wikipedia.org/wiki/Gamma_spectroscopy

Note gamma and X ray frequencie ranges sunstantially overlap.

The difference is the nature of source.

Then, I will re-phrase. Measuring gamma ray frequencies without using energy detector and E=hf.  

1 hour ago, swansont said:

You can do diffraction with x-rays and gammas. Crystal lattices have spacing that is appropriate for this. X-ray crystallography would work with some gammas

 

1 hour ago, swansont said:

You can do diffraction with x-rays and gammas. Crystal lattices have spacing that is appropriate for this. X-ray crystallography would work with some gammas

Then what about those outside of the possible "some" ranges; the higher known frequencies.

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43 minutes ago, avicenna said:

Then, I will re-phrase. Measuring gamma ray frequencies without using energy detector and E=hf.  

Why? What is the relevance of that?

43 minutes ago, avicenna said:

Then what about those outside of the possible "some" ranges; the higher known frequencies.

Maybe if you explained what you want to know, and why, you might get a better answer than this, "yes, but not that" approach.

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1 hour ago, avicenna said:

Then what about those outside of the possible "some" ranges; the higher known frequencies.

Really high energy gamma photon is able to create pair of matter-antimatter, in pair-production effect,

https://en.wikipedia.org/wiki/Pair_production

and cause particle shower

https://en.wikipedia.org/wiki/Particle_shower

or photo-disintegrate nucleus.

https://en.wikipedia.org/wiki/Photodisintegration

Observation of these effects reveal that high energy photon collided with our medium.

 

Pair-production requires gamma photon with at least 1.022 MeV energy or more.

Photodisintegration of Deuterium requires gamma photon with at least 2.22 MeV energy or more.

 

Edited by Sensei

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5 hours ago, studiot said:

 

 

5 hours ago, studiot said:

Why is this not direct?

What do you mean by direct?

Frequency analysis of gamma rays is called gamma ray spectroscopy

https://en.wikipedia.org/wiki/Gamma_spectroscopy

Note gamma and X ray frequencie ranges sunstantially overlap.

The difference is the nature of source.

Bragg's law : nλ = 2d Sinθ relates wavelength of x-rays "directly" to angle. I consider this direct.

Can this be used for all gamma rays.

 

In E=hf, we need to assume an energy to frequency relation and so it is "indirect."

 

Edited by avicenna
typo

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10 minutes ago, avicenna said:

 

Bragg's law : nλ = 2d Sinθ relates wavelength of x-rays "directly" to angle. I consider this direct.

Can this be used for all gamma rays.

 

In E=hf, we need to assume an energy to frequency relation and so it is "indirect."

We don’t need to “assume” it, as you can confirm that the relationship holds. But you seem to be suggesting that Bragg’s law is somehow on firmer footing, which is confusing. Both of these rely on an indirect method using a mathematical relationship. Which is widespread in physics and especially so in QM

 

 

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20 minutes ago, avicenna said:

In E=hf, we need to assume an energy to frequency relation and so it is "indirect."

This just as direct as Bragg!s law

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36 minutes ago, Strange said:

This just as direct as Bragg!s law

You may say so. But if Bragg's method can be used for all gamma ray, does it not bypass the relation E=hν. What if there is a method so "direct" that it requires 99 more relation in between?

Can Bragg's method be used for all gamma rays?

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Can't see how you can do Bragg without a gamma detector.

How do you think a gamma detector works, if not by energy?

At the risk of another silly argument over the word interact I don't know of any detector that doesn't interact with the gamma energy.

If someone else does know of one please tell us, I would pleased to learn about it.

Edited by studiot

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1 hour ago, studiot said:

Can't see how you can do Bragg without a gamma detector.

How do you think a gamma detector works, if not by energy?

At the risk of another silly argument over the word interact I don't know of any detector that doesn't interact with the gamma energy.

If someone else does know of one please tell us, I would pleased to learn about it.

That’s not the argument. The OP is asking for detection that does not try to measure the energy.

You could expose film to do the measurement. Or something like a CCD. You want position information. You don’t need a detector that tells you the energy.

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