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From: smlg1015@uxa.cso.uiuc.edu
Newsgroups: sci.electronics
Subject: Vacuum Terminology
Message-ID: <108800006@uxa.cso.uiuc.edu>
Date: 28 Jan 90 17:15:00 GMT
Lines: 13
Nf-ID: #N:uxa.cso.uiuc.edu:108800006:000:387
Nf-From: uxa.cso.uiuc.edu!smlg1015    Jan 28 11:15:00 1990


Dear sci.electronics:

Can somebody familiar with vacuum technology tell me to what the terms,
"high vacuum","ultra high vacuum", and "super high vacuum" correspond?

In particular, 10E-7 particles per cm3 corresponds to which category?
This is said to be the density of an interstellar dust cloud.  What's
the best that can be achieved in the lab?

Thanks,

smlg1015@uxa.cso.uiuc.edu