234UncleBob
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Many Thanks to any one who replies in advance!

What does the area under an "intensity of X-rays" vs Wavelength graph tell us?
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LuigiMario
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It’s the sort of answer/thing hiding in your textbook!

Probably a long German word

“Braking radiation” now, what might that be in a foreign lingo?

“X-rays are emitted as the electrons slow down (decelerate) in the metal(target). The output spectrum consists of a continuous spectrum of X-rays, with additional sharp peaks at certain energies. The continuous spectrum is due to ..............., while the sharp peaks are characteristic X-rays associated with the (particular metal) atoms in the target
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234UncleBob
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(Original post by LuigiMario)
It’s the sort of answer/thing hiding in your textbook!

Probably a long German word

“Braking radiation” now, what might that be in a foreign lingo?

“X-rays are emitted as the electrons slow down (decelerate) in the metal(target). The output spectrum consists of a continuous spectrum of X-rays, with additional sharp peaks at certain energies. The continuous spectrum is due to ..............., while the sharp peaks are characteristic X-rays associated with the (particular metal) atoms in the target
Bremsstrahlung? What that got to do with this?
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234UncleBob
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(Original post by 234UncleBob)
Bremsstrahlung? What that got to do with this?
I found it, the area under the graph is the total no. of electrons.
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LuigiMario
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Bremstrahlung IS the area under the X-ray curve, [apart from the ‘spectroscopy’ peaks which although a peak, is still under the curve] along those lines....
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LuigiMario
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Wow, I never saw that coming.

Tho’ brem is directly electron related/proportional
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234UncleBob
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(Original post by LuigiMario)
Bremstrahlung IS the area under the X-ray curve, [apart from the ‘spectroscopy’ peaks which although a peak, is still under the curve] along those lines....
That's energy though, are you sure it's not the number of electrons?
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234UncleBob
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(Original post by 234UncleBob)
That's energy though, are you sure it's not the number of electrons
(Original post by LuigiMario)
Wow, I never saw that coming.

Tho’ brem is directly electron related/proportional
Saw what coming?
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LuigiMario
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Yes no. of electrons, seems ok (crossposting)
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234UncleBob
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(Original post by LuigiMario)
Yes no. of electrons, seems ok (crossposting)
lol.

Ok thanks!!!

If i do come across anything else, would you mind?
Last edited by 234UncleBob; 3 weeks ago
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LuigiMario
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Give it a shot, I usually pass by regularly
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234UncleBob
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(Original post by LuigiMario)
Give it a shot, I usually pass by regularly
Many Thanks in Advance!

What is the difference between Physical and Effective half life?
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LuigiMario
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Drat, I should have kept my cd-rom table of isotopes!
(Though it was revised quite often, as more data came in)

That could be the difference, all the millions of text-books state the half-life, presumably that’s a statistical effective half life? Whilst when you get the vial of, from memory, Europium 152, you might find it at variance. I personally think that unless you measure t^0.5 very carefully, inside a Cern experimental area, surrounded by Roman recovered lead from ancient shipwreck keels, then you’ll get some environmentally initiated fission, hence a bias in experimental results.

Look at Google, they allegedly discovered across their server farms, that the uppermost computers in the server rack have a greater soft-error rate (ram/disk bitflips) than the lower server pc’s in the racks. Incoming cosmic rays, flipping big silicon chips. That means that the natural spontaneous half-life in some places, isn’t. Higher altitude = more stray protons.

Who built NIST on top of a mountain?
https://www.nist.gov/pml/nuclear-physics-data

Just my thoughts, you’ll find the official answer at https://scholar.google.com
Last edited by LuigiMario; 3 weeks ago
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234UncleBob
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(Original post by LuigiMario)
Drat, I should have kept my cd-rom table of isotopes!
(Though it was revised quite often, as more data came in)

That could be the difference, all the millions of text-books state the half-life, presumably that’s a statistical effective half life? Whilst when you get the vial of, from memory, Europium 152, you might find it at variance. I personally think that unless you measure t^0.5 very carefully, inside a Cern experimental area, surrounded by Roman recovered lead from ancient shipwreck keels, then you’ll get some environmentally initiated fission, hence a bias in experimental results.

Look at Google, they allegedly discovered across their server farms, that the uppermost computers in the server rack have a greater soft-error rate (ram/disk bitflips) than the lower server pc’s in the racks. Incoming cosmic rays, flipping big silicon chips. That means that the natural spontaneous half-life in some places, isn’t. Higher altitude = more stray protons.

Who built NIST on top of a mountain?
https://www.nist.gov/pml/nuclear-physics-data

Just my thoughts, you’ll find the official answer at https://scholar.google.com
??? What is the difference between Physical and Effective half life of a radioisotope?
I'm lost
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LuigiMario
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Sorry, it was buried at the end of the waffle

Try this instead - you have to find your answers

https://scholar.google.com/scholar?h...lf+life+&btnG=

(Loads of actual comparisons)
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LuigiMario
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Such as this quote

“Adjustment of this flux value for decay of the neutron source was later introduced and was based on the physical half-life of 238Pu. The current findings would suggest, however, that a more appropriate value for the effective half-life for the total body irradiator is 141.7+or-2.5 y. In addition, variations in the induced counts for a Mn standard on a yearly basis indicate that seasonal differences of approximately 0.5% can be present between the winter and summer months”

The physical half-life is the book/cd-rom value
The effective half-life includes the experimental errors & other stuff, note a SEASONAL component! So I guess my cosmic-ray idea is likely one of the actual errors that leads to a typical effective half-life, look it up further
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234UncleBob
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(Original post by LuigiMario)
Such as this quote

“Adjustment of this flux value for decay of the neutron source was later introduced and was based on the physical half-life of 238Pu. The current findings would suggest, however, that a more appropriate value for the effective half-life for the total body irradiator is 141.7+or-2.5 y. In addition, variations in the induced counts for a Mn standard on a yearly basis indicate that seasonal differences of approximately 0.5% can be present between the winter and summer months”

The physical half-life is the book/cd-rom value
The effective half-life includes the experimental errors & other stuff, note a SEASONAL component! So I guess my cosmic-ray idea is likely one of the actual errors that leads to a typical effective half-life, look it up further
Thanks!
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234UncleBob
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(Original post by 234UncleBob)
Thanks!
Many Thanks in Advance to whoever replies!

How do you derive the units (in detail) for mass attenuation coefficient?
I'm confused with how to work out the units from kg/m^3 x m^-1.
A little help would be appreciated.
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234UncleBob
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(Original post by 234UncleBob)
Many Thanks in Advance to whoever replies!

How do you derive the units (in detail) for mass attenuation coefficient?
I'm confused with how to work out the units from kg/m^3 x m^-1.
A little help would be appreciated.
Never mind, just figured it out!
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