How is positrons and anti-hydrogen created?

[alemsalem]

I just read that physicists at CERN created anti-hydrogen, and I'm wondering how exactly do you create positrons or anti-protons do you collide something and then somehow pick the mass and charge of the positron or is it created by itself? same for anti-protons?

 

[cragar]

You can create positrons by shooting high energy gamma rays into the nucleus of some atoms and it can cause pair production. Not sure if this is how they did it though.