linac energy


by Pseudo Epsilon
Tags: energy, linac
Pseudo Epsilon
Pseudo Epsilon is offline
#1
Apr23-13, 11:20 AM
P: 102
Hi all, this is my first time posting.

This may seem too vauge but could a 2m long linac accelerating electrons (with electron gun as source) achive 1.5MeV? I.e. Could it make positrons via pair production? (0.511MeV For electron same for positron plus a litle extra to be safe) asuming it uses quadropole and sextupole magnets (copper) liquid nitrogen cooled. Electrostaticly acelerated via muliple staged electrodes (max voltage=~100 000v). Thanx to you geniuses in advace
Phys.Org News Partner Physics news on Phys.org
The hemihelix: Scientists discover a new shape using rubber bands (w/ video)
Mapping the road to quantum gravity
Chameleon crystals could enable active camouflage (w/ video)
Bill_K
Bill_K is offline
#2
Apr23-13, 11:44 AM
Sci Advisor
Thanks
Bill_K's Avatar
P: 3,864
The 2-mile long linac you may be speaking of was the one at SLAC, which achieved 90 GeV center-of-mass energy.
Pseudo Epsilon
Pseudo Epsilon is offline
#3
Apr23-13, 12:26 PM
P: 102
i meant two meters. 1.5 Mev posible using only electrostatic aceleration?

Bill_K
Bill_K is offline
#4
Apr23-13, 12:47 PM
Sci Advisor
Thanks
Bill_K's Avatar
P: 3,864

linac energy


Sorry, my mistake. You're actually thinking of building a table-top linac?? Good luck generating and storing the positrons. Good luck getting the beams to collide. And don't forget to watch out for the radiation produced when the beams hit the backstop!
mfb
mfb is offline
#5
Apr23-13, 01:46 PM
Mentor
P: 10,864
1.5 MeV with 2 meters of separation is possible with electrostatic acceleration (but 3-4m would be easier), and you can use the 1.5MeV-electrons to do pair production afterwards. Focusing is neither necessary nor practical with such a small setup, I think. You just need a good insulation and a Van-de-Graaff generator. If you want to do something with the positrons, the setup will grow.
Pseudo Epsilon
Pseudo Epsilon is offline
#6
Apr23-13, 01:57 PM
P: 102
thanks! I wasn't planning to do anything with the positrons yet. Thanks for not being harsh. If i may ask what target should i use and could i detect the positrons?
Pseudo Epsilon
Pseudo Epsilon is offline
#7
Apr23-13, 02:03 PM
P: 102
oh, and could i use a flyback transformer coupled to a cfl circuit instead of a van de graff generator?
mfb
mfb is offline
#8
Apr23-13, 02:12 PM
Mentor
P: 10,864
As target: probably something where the electrons can produce high-energetic photons, and those can be converted to electron/positron pairs afterwards - a material with heavy nuclei? Gold is expensive, lead is toxic.
I wasn't planning to do anything with the positrons yet.
This is nothing you should do at home. It is very dangerous, and probably illegal.
Pseudo Epsilon
Pseudo Epsilon is offline
#9
Apr23-13, 02:28 PM
P: 102
i will check with my local police station. But is there any cheap way to confirm positrons have been produced? And how about tungsten for a target?
mfb
mfb is offline
#10
Apr23-13, 02:37 PM
Mentor
P: 10,864
i will check with my local police station.
The police station won't tell you how to avoid getting killed, or injured.
But is there any cheap way to confirm positrons have been produced?
There is. If you know enough to build such a device safely, you will know the answer to that question.
Pseudo Epsilon
Pseudo Epsilon is offline
#11
Apr23-13, 03:01 PM
P: 102
but a device with a 100% acuracy that only detects positrons? And by the way, i always do my research once i know what to research. I am familiar with high voltage safty as i have built a jacobs ladder and tesla coil in the past. I do already have lead-impregnated glass for the hard radiation from a recycling company.
Pseudo Epsilon
Pseudo Epsilon is offline
#12
Apr23-13, 03:50 PM
P: 102
so if you could just tell me the name of the detector needed. Please.
berkeman
berkeman is online now
#13
Apr23-13, 04:40 PM
Mentor
berkeman's Avatar
P: 39,721
Pseudo Epsilon -- We do not allow discussions of dangerous activities here on the PF. This thread is closed. Please do not ask questions like this here again.


Register to reply

Related Discussions
Amateur Linac Experiment High Energy, Nuclear, Particle Physics 4
Radio Frequency Quadrupole Linac Question Nuclear Engineering 3
time in Linac Introductory Physics Homework 0
cosmological constant or dark energy or vaccum denisty/energy/energy density Astrophysics 9
LINAC for Cancer Treatment High Energy, Nuclear, Particle Physics 6