P. Repa et al., Measurement of pressure differences between various positions in a vacuum chamber where pressure is generated dynamically, METROLOGIA, 36(6), 1999, pp. 551-554
The pressure differences between the positions for gauge connection in a ch
amber for gauge comparison were measured and evaluated in two ways: (a) by
the mutual interchange of two ionization gauges at the positions; and (b) b
y readings of one ionization gauge at various positions and of a spinning r
otor gauge at a fixed position. The pressure in the chamber was set up by s
imultaneous admission and pumping of the gas. Differences of the order of a
few percent were observed, probably caused by imperfect adjustment of the
gas-introducing jet. Those differences are specific to the given apparatus,
they depend on its adjustment, the geometry and some other parameters. The
two methods are suitable for checking and adjusting the apparatus.