To begin, I'm not sure if this is the right subforum for my question, and whether questions like this, in particular, questions about the details of personal projects, are allowed on this forum. Being new to this forum, if I have made any mistake in this regard, I apologize in advance, and will be willing to adapt my question if necessary. Setting that aside, I have recently begun looking into a project that involves maintaining a medium vacuum in a cylindrical container (most likely a bell jar) roughly 20-25cm on all sides. I would like to achieve a vacuum of 1–10 pascals (7.5–75 millitorr). Have any of you had particular experience with setups like these, and if so, what vacuum pump do you think would be best used for this particular situation? I have never worked with vacuum pumps before, so I am a bit naive about vacuum pump brands, tubing for such pumps, and the containers themselves.