Vernier Software and Technology
Vernier Software & Technology

Background Radiation Sources


When a Geiger counter is operated it will usually record an event every few seconds, even if no obvious radioactive source is placed nearby. Where do these counts come from?

Two significant sources are cosmic rays and radon decay products. Cosmic rays, as the name suggests, are fast-moving particles from space that enter the Earth’s atmosphere, along with their decay products. Since the atmosphere absorbs some of these particles, the rate of detection of cosmic rays increases with increasing altitude. If you were to take a Geiger counter on a cross-country jet flight, you would observe a marked increase in count rate while at high altitude.


In this experiment, you will

  • Concentrate naturally occurring radioactive substances using a charged balloon.
  • Use a radiation counter to detect emissions from naturally occurring radioactive substances.
  • Determine the effective lifetime of the collection of radon decay products.

Sensors and Equipment

This experiment features the following Vernier sensors and equipment.

Additional Requirements

You may also need an interface and software for data collection. What do I need for data collection?

Standards Correlations

See all standards correlations for Nuclear Radiation with Vernier »

Nuclear Radiation with Vernier

See other experiments from the lab book.

1α, β, and γ
2Distance and Radiation
3Lifetime Measurement
4Counting Statistics
5Background Radiation Sources
6Radiation Shielding

Experiment 5 from Nuclear Radiation with Vernier Lab Book

<em>Nuclear Radiation with Vernier</em> book cover

Included in the Lab Book

Vernier lab books include word-processing files of the student instructions, essential teacher information, suggested answers, sample data and graphs, and more.

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