The CR-200-4us-R2.1 is a Gaussian shaping amplifier module, and is used to read out the tail pulse signals such as from charge sensitive preamplifiers, PMTs, and other similar detection circuits. Gaussian shaping amplifiers are also known as pulse amplifiers, linear amplifiers, or spectroscopy amplifiers in the general literature. They accept a step-like input pulse and produce an output pulse shaped like a Gaussian function (bell curve). The purpose of these amplifiers is not only to transform the shape of the event pulse from a tail pulse to a bell curve, but also to filter much of the noise from the signal of interest. Use of shaping amplifiers will reduce the fall time of the pulse signals, reducing the incidence of pulse pile up, and improve the signal-to-noise of the detection system.