Geiger and Marsden experiment. How did they create a vacuum?

[1st]

Hi, I would just like to know how did Geiger and Marden create a vacuum for alpha particles during the Rutherford scattering experiment? Also, when Rutherford discovered the alpha particle did he know it had +2e charge?

Any help would be appreciated. I've looked everywhere for the answers but can't find them anywhere :(

Thanks

 

[ideasrule]

I couldn't find out how they created the vacuum, but I suspect they just used a normal vacuum pump. It's not exotic technology, considering that it was invented in 1650.

As for the alpha particles, he used a mass spectrometer to measure their charge to mass ratio. Since he got 0.5e/amu, he guessed that they were helium nuclei. To prove that they were actually helium nuclei, he trapped the ions, neutralized them, and analyzed the spectrum. See here: http://en.wikipedia.org/wiki/Alpha_particle#History_of_discovery_and_use