Fast Timing Discriminators

• Designed for precise timing measurement of fast detector signals
• Enables picosecond to nanosecond timing resolution for advanced experiments
• Supports high counting rates up to tens of MHz or higher
• Available technologies:
• Leading-edge discrimination
• Constant-fraction discrimination (CFD) for superior timing accuracy
• Minimizes time walk (timing error due to pulse amplitude variation)
• Compatible with ultra-fast detectors:
• PMTs
• Microchannel plate detectors
• Fast silicon photodiodes
• Multi-channel options for parallel timing and coincidence systems
• NIM-standard modules for laboratory integration

Fast timing discriminators are specialized electronic instruments used in radiation detection systems to determine the precise arrival time of detector pulses.

Unlike standard discriminators, these devices operate on fast-rising signals and are optimized to achieve extremely high timing precision. They convert analog detector pulses into digital logic signals, marking the exact moment a radiation event occurs.

Two primary timing techniques are used:

Leading-Edge Discrimination
→ Simple threshold-based timing, suitable for fast signals but sensitive to amplitude variations
Constant-Fraction Discrimination (CFD)
→ Advanced method that triggers at a constant fraction of the pulse height, significantly reducing timing errors (time walk) and improving accuracy

ORTEC provides a wide range of fast timing discriminators, including models such as:

• Model 584 Constant-Fraction Discriminator
• Model 9307 pico-Timing Discriminator
• Model 9327 1-GHz Amplifier & Timing Discriminator
• CF8000 Multi-channel CFD systems

High-end models can achieve picosecond-level timing precision with minimal jitter and excellent stability, even when input pulse amplitudes vary significantly.

These instruments are essential for applications requiring precise time correlation, coincidence detection, and time-resolved measurements.

Product Type: Fast Timing Discriminator (NIM module)
Function:

• Pulse timing detection
• Analog-to-logic signal conversion
• Event time marking

Timing Resolution: Picosecond to nanosecond range (model-dependent)
Timing Techniques:

• Leading-edge discrimination
• Constant-fraction discrimination (CFD)

Input Signal:

• Fast analog pulses (sub-nanosecond rise time)
• Typical amplitude range: mV to volts

Threshold Range: Adjustable (e.g., ~mV to V range depending on model)
Time Walk: As low as ±20 ps to ±100 ps (model-dependent)
Maximum Counting Rate: Up to tens of MHz (e.g., 50 MHz typical)
Outputs:

• Fast NIM logic outputs
• TTL outputs (model dependent)

Channel Options:

• Single-channel
• Multi-channel (quad, octal systems)

Form Factor: NIM modular electronics

• Time-of-flight (TOF) measurements
• Coincidence and anticoincidence experiments
• Nuclear and particle physics research
• Fluorescence and lifetime spectroscopy
• LIDAR and fast optical detection systems
• High-speed photon and ion detection
• Accelerator and beamline experiments