# Accelerator and Beams - Tools for Discovery and Innovation

1. Jun 7, 2009

### ZapperZ

Staff Emeritus
The Division of Physics of Beams of the American Physical Society (APS) has produced this wonderful brochure titled "http://www.aps.org/units/dpb/upload/brochure.pdf" [Broken]". It essentially describe what a particle accelerator is, and more importantly, what it is used for.

The main purpose here is to eliminate the wrong myth that "particle accelerator" automatically means "particle collider" in high energy physics. Nothing could be further than the truth, and hopefully, someone reading this brochure will get the idea that the MAJORITY of the application for a particle accelerator has NOTHING to do with high energy physics.

A supplement for this brochure is a useful article written a while back by Michael Turner titled "http://scitation.aip.org/journals/doc/PHTOAD-ft/vol_56/iss_9/10_1.shtml" [Broken]", that essentially tried to convey the same message.

Zz.

Last edited by a moderator: May 4, 2017
2. Jun 8, 2009

### Bob S

Here is a free downloadable book on the "Principles of Charged Particle Acceleration" by Stanley Humphries. warning: large file -11.3 MB
http://www.fieldp.com/cpa.html
Or you can get a used one from Amazon.com for \$75.00

Last edited: Jun 8, 2009
3. Jun 10, 2009

### scupydog

Thanks for the link, it looks like good read. i just started reading the introduction and on page 3 Humphries states that " magnetic forces cannot affect a particles kinetic energy".
1 question.
Do the photons of synchrotron radiation not carry away/convert the kinetic energy of the particle?

4. Jun 11, 2009

### Bob S

You are correct in that sunchrotron radiation is a direct consequence of the F = q(v x B) (Lorentz) force. I think the author was trying to say is that since both B and F are orthogonal to v, no work is being done, and the force does not add to or subtract from the velocity.
Bob S

5. Jun 11, 2009

### scupydog

thx for reply Bob, where does the energy come from for synchrotron radiation.... is there a change in mass of the charged particle, or is the ammount of energy needed for S.R. equal to the magnetic energy/force applied to the particle.

6. Jun 11, 2009

### Bob S

The synchrotron radiation comes from the deflection of positrons or electrons in bending magnets. it orthogonal to the velocity in the center of mass coord system, but is very forward radiation in the lab system, and comes from the particles' kinetic energy, which is replaced by RF cavities. I have seen potted copper coils on magnets turn black and crack by synchrotron radiation damage.

Last edited: Jun 11, 2009
7. Jun 11, 2009

### scupydog

Hi Bob i,m interested in acceleraters and have visited CERN do you work with acceleraters?

8. Jun 11, 2009

### ZapperZ

Staff Emeritus
Er... you should be very careful here not to use "E=mc^2" in this process. This is simply classical E&M. The electron (or electron bunch) is losing kinetic energy in such a process.

Zz.

9. Jun 11, 2009

### Bob S

How about E2= (pc)2+ (m0c2)2 ?