N1168

The  CAEN Mod.N1168 is suitable for several type of scintillator detectors, particularly where different decay time of the scintillation light are present. This module allows to obtain the full handling of the detector signal, giving the total energy, amplitude of the fast component and the time information.
The analysis of the two dimensional spectrum (fast versus total) allows an excellent gamma-neutron separation for liquid scintillators or CLYC detectors, gamma-charged particle separation for BaF2 detectors, and to disentangle the gamma interaction in the different parts of a Phoswich detector.

For scintillator detectors with a single light component, the fast output can be used as a second total energy output, meeting the requirements of dual energy range experimental setups, avoiding the split of the signal on two shaping amplifiers.
The module is very simple to use and overcomes the inconveniences of the standard approach with two gates and QDC setup.

The board has two outputs for each input channel, where the first output is proportional to the integration charge (called SLOW output), and the second is proportional to the signal amplitude (called FAST output). The latter gives information of the shape of the input pulse, thus giving information to perform pulse shape discrimination with detectors that have a different response to particles, like gamma-neutrons.

For scintillator detectors with a single light component, the AUX output, that is a second slow output, can be used as a second total energy signal, meeting the requirements of dual energy range experimental setups, avoiding the split of the signal on two shaping amplifiers.
A gate-free fast stretcher circuit captures the leading-edge peak value of the signal, that is subsequently Gaussian shaped to allow simple acquisition by a peak-sensing ADC.

The total energy circuit basically consists of an integrator, followed by a Gaussian shaper amplifier. The time information is given by a Constant Fraction Discriminator, with selectable delay line and an automatically walk compensation circuit.
The very low noise level of the module matches the requirements of the new class of high energy resolution scintillators (LaBr3), over a large energy dynamics applications range, and also in a very low discrimination level.

A software tool that allows an easy management of all the functional parameters of the CAEN Spectroscopy Amplifiers is available too; supported operating systems are Windows and Linux.

(Designed in collaboration with INFN Milano).