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

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Geiger and Marsden likely created a vacuum for alpha particles in their experiment using a standard vacuum pump, a technology available since the 17th century. Rutherford did not initially know the alpha particle had a +2e charge; he determined its charge-to-mass ratio using a mass spectrometer. By obtaining a ratio of 0.5e/amu, he inferred that alpha particles were helium nuclei. Further confirmation involved trapping the ions, neutralizing them, and analyzing the resulting spectrum. This process ultimately validated the identity of alpha particles as helium nuclei.
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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
 
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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
 

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