B If you had to make a perfect vacuum, version #2

[mfb]

All the vacua we are discussing here have mean free paths way larger than the size of the lab vacuum.

Interstellar space has mean free path in the range of millions to trillions of kilometers. Large compared to planets and most stars, but small compared to interstellar distances.

 

[Andreas C]

All the vacua we are discussing here have mean free paths way larger than the size of the lab vacuum.

Interstellar space has mean free path in the range of millions to trillions of kilometers. Large compared to planets and most stars, but small compared to interstellar distances.

Do you know what the density of antiprotons is in there?

 

[mfb]

Did you check the publication? It should have numbers for the antiprotons and the approximate volume of their storage. The total vacuum volume is 1.2 l but that won't be filled with antiprotons. They used a few thousand antiprotons for measurements, so initially the number of antiprotons clearly exceeded the number of regular atoms in the trap.