Industrial grade positron formation

[skullcracker]

Is there any way to economically produce positrons using particle accelerators or any other method?

 

[daveb]

Sure. Just irradiate some material ina particle accelerator that would become a positron emitter. Look up the process for creating F-18.

 

[Bill_K]

The accelerators typically produce positrons by letting a beam of gamma rays strike a target. This creates electron-positron pairs, which are then separated and thermalized.

 

[skullcracker]

ok so is it possible to form positrons by bombarding electrons on a material (tungsten or lead - because of its high atomic no.)? because electrons on colliding with other electrons basically produce x rays which are basically low energy gamma raysso these gamma rays can produce positron electron pairs

 

[Bill_K]

Here's a report on a positron source that does it that way:

"Positrons are generated via pair creation when energetic electrons are stopped in a high-Z target, the electron-positron converter. These positrons are then moderated, i.e. slowed to thermal energies, via interaction with a suitable material such as tungsten, and a slow positron beam produced."

http://arxiv.org/abs/1102.1220

 

[skullcracker]

what would be the efficiency of this method?

 

[Vanadium 50]

It's in the paper that Bill_K pointed you to. It's even in the abstract. We can point you to papers, but you have to read them yourself.

 

[jambaugh]

Reading the thread title, my first question was
So positrons come in different grades?

I'll take 36 industrial grade positrons and 204 consumer grade positrons if you please! ;)

 

[Vanadium 50]

Prime, choice, select, standard, commercial, cutter and canner. (Mmmm...utility grade positrons)

And nuclei come in sizes small, medium, large, extra large, jumbo, giant, colossal and super colossal.

 

[jambaugh]

...And nuclei come in sizes small, medium, large, extra large, jumbo, giant, colossal and super colossal.

So that's the REAL reason for the "non commuting c-numbers"! It's a promotional gimmick!

SUPER-SIZE ME!

 

[skullcracker]

can anyone express the efficiency in billi_k's link in terms of percentage?

 

[Vanadium 50]

I'm sure they can. Where are you getting stuck in the calculation?

 

[skullcracker]

ummm.. at the beginning the calculation was a bit complicated

 

[Vanadium 50]

Show us how far you got, please.

 

[skullcracker]

ok so the abstract said "For an electron beam energy of 5 MeV (10 MeV) and current 240 $\mu$A (30 $\mu$A) production of a slow positron beam of intensity 5 $\times$ 10$^{6}$ s$^{-1}$ is predicted. The simulation also calculates the average energy deposited in the converter per electron, allowing an estimate of the beam heating at a given electron energy and current. For low energy, high-current operation the maximum obtainable positron beam intensity will be limited by this beam heating."

however i could not get the SI unit so can anyone tell me the SI unit as well as the formula for converting this unit into percentage

 

[skullcracker]

Can anyone tell me how many grams of positrons would be generated in one hour?

 

[xts]

production of a slow positron beam of intensity 5 $\times$ 10$^{6}$ s$^{-1}$ is predicted.

Can anyone tell me how many grams of positrons would be generated in one hour?

Skullcracker, if you know how many positrons are created in one second, then you know how many seconds are in one hour, and you know what is positron mass (if you don't - wiki it), then you should be able to answer your question yourself. If not, ask your 3rd grade primary school ma'am for help.

 

[skullcracker]

xts u dint get the question i wanted to know what 'production of a slow positron beam of intensity 5 $\times$ 10$^{6}$ s$^{-1}$ is predicted.'meant and i don't think third grade teachers would be teaching particle physics

 

[Vanadium 50]

We're done here.