Systems and methods are provided to perform dead time correction. An observed ion count rate is obtained using a non-paralyzable detection system of a mass spectrometer. The detection system includes an ion detector, a comparator/discriminator, a mono-stable circuit and a counter. The non- paralyzable detection system exhibits dead time extension at high count rates. The extension of the dead time occurs because the mono-stable circuit requires a rising edge to trigger and can only be triggered again after the output pulse from the comparator/discriminator has gone low. This allows a second comparator/discriminator pulse arriving just before the end of the dead time started by a first comparator/discriminator pulse to extend the dead time to the trailing edge of the second comparator/discriminator pulse. A true ion count rate is calculated by performing dead time correction of the observed ion count rate.