# High Sensitivity Source – News

Sensitivity of IRMS instruments is a measure of the sample input vs. the signal observed, and is expressed as molecules / ion. It depends on a number of factors: the trap current, which controls how many electrons enter ion source, the number of collisions between the electrons from the filament and the molecules of sample in the source, and the efficiency of extracting the ions produced and transferring them to the collectors

Development work at Sercon has optimised the design of the Nier-type source, improving the efficiency by  15%, improving the sensitivity and extending the range of trap current in which it is effective to operate.

The new high sensitivity IRMS from Sercon, the HS20-22, has a sensitivity specification of <650 molecules / ion for CO2 in dual inlet mode at 600µA trap current, making the HS2022 is now the most sensitive small radius IRMS on the market.