Xrays And you What are Xrays As you

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X-rays And you

X-rays And you

What are X-rays? ? ? • As you know, X-rays are a high frequency

What are X-rays? ? ? • As you know, X-rays are a high frequency form of electromagnetic energy • Short wavelength (high energy) according to the wave model • Photons with a lot of energy according to the particle model

Where do they come from? • We generate X-rays via the rapid deacceleration of

Where do they come from? • We generate X-rays via the rapid deacceleration of electrons – like this: − + ° − + ✗ Dense heavy metal Like tungsten

The process is called: • Bremsstrahlung • = braking radiation – when the e-

The process is called: • Bremsstrahlung • = braking radiation – when the e- hits the metal plate, it de-accelerates.

Did you know? • X-rays have a variety of wavelengths? ? ? (due to

Did you know? • X-rays have a variety of wavelengths? ? ? (due to various rates of de-acceleration) • Well what would a graph of the wavelengths produced look like? • Great question!!!

Intensity (# photons/s) Related to # e- / s Max E (small λ) cut

Intensity (# photons/s) Related to # e- / s Max E (small λ) cut off . 04 λ (nm) An e- w/ 5 x 10 -15 J of E will produce a photon w/ 5 x 10 -15 J of E (max) . 1

What are those weird peaks? • Great question!!!!!!!!! • When the in-coming e- knocks

What are those weird peaks? • Great question!!!!!!!!! • When the in-coming e- knocks out inner shell e- s (n=1 or n=2), a “hole” is created. An outer shell e- can drop in to take the place of the displaced e-. When this happens, additional xray energy is released – hence the odd spikes. • Recall that these metals have many orbitals so the drop from an outer orbital is a significant change in energy!

So does that mean • That if you use different metal – the spikes

So does that mean • That if you use different metal – the spikes will not be in the same place? ? • Yes, this is true grasshopper. The spikes will shift depending on the type of metal used.

What would an X-ray of your brain full of knowledge look like? • Like

What would an X-ray of your brain full of knowledge look like? • Like this:

 • Actually I know that one is an MRI. But it is more

• Actually I know that one is an MRI. But it is more interesting than a x-ray image – so there!