Product Spotlight: Lascells Spark Detector

Spark-Detector for Alpha-Radiation Demonstrations

Lascells Multi‑Wire Spark Detector provides a dramatic and memorable way to demonstrate the ionising properties of alpha particles. In this apparatus, multiple fine wires are mounted above a metal plate to form a high-voltage air gap. When the potential across the gap reaches roughly 4500 V, rare ionising events cause a visible spark.

When a sealed alpha-radiation source is brought near the detector, the rate of sparking rises sharply, giving an unmistakeable visual and auditory signal of ionisation. As alpha particles are strongly ionising but have very short range and poor penetration through air, this behaviour clearly demonstrates the nature of alpha radiation. 

This makes the Spark Detector particularly useful in educational settings: it gives students and technicians a direct, tangible experience of radiation that is often abstract or invisible. 

Because the Spark Detector responds primarily to alpha particles (which ionise air efficiently), it’s a simple and effective complement to other detection methods such as cloud chambers or Geiger–Müller tube.

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