Isoprime User’s Guide
Version 1.02 IsoPrime100 User’s Guide Page 30 of 219
The signal leads from the collectors are double screened to avoid any pickup from unwanted
ions. The leads connect to the ten-pin collector feed-through which is located inside the feed-
through shroud. The locations of the feed-throughs for the Major, Minor 1, Minor 2 and Mass 2
collectors are shown below:
View of Collector feed through from Inside of the Housing
To measure hydrogen in dual inlet mode, the hydrogen collector option is required. This
includes an additional Faraday cup that is positioned on the edge of the mounting plate, closest
to the magnet. This cup is used to collect the mass 2 beam, whilst the mass 3 beam is collected
in the minor 2 Faraday.
ESF COLLECTOR
In order to measure precise HD/H2 (D/H) ratios by continuous flow, the hydrogen ESF
(Electrostatic Filter) option collector is required. The mass 2 ions are collected in the cup as
shown below. The HD ions pass through a small ESF and into the repositioned minor 2 collector.
The ESF is an energy filter that reduces the low energy He+ peak tail that would normally be
superimposed on the HD+ signal during continuous flow analysis. The
peak tail represents helium ions that have lost energy during collision with gas
molecules in the flight tube. The result of the energy loss is that the flight path of the ions is
altered, and the ions arrive at the collector at a lower mass position
than would normally be the case. The ESF is set up to reject any ions that have lost any of their
original source energy.
To Next Page