Principle
An alpha-spectrometer, consisting of a silicon surface barrier
layer detector, a preamplifier, a pulse height analyser and a
recording device for registration of the spectra is calibrated by
means of an open alpha-emitter of known alpha-energy (241Am). The energy
spectrum of a radium source which is in equilibrium with its decay
products, is recorded and evaluated. The alpha-energies found in
this way are allocated to the corresponding nuclides of the radium
decay series.
Tasks
- The alpha-spectrum of the 226Ra is recorded,
the settings of the pulse analyzer (amplification) and recorder (x
and y input sensitivity) being selected so as to make best possible
use of the recording width.
- The calibration spectrum of the open 241Am-emitter is
recorded at the same settings.
- The alpha-energies corresponding to the individual peaks of the
alpha spectrum of the radium are calculated and, on the assumption
of a constant energy loss in the source covering, the alpha-active
nuclides of the radium decay series corresponding to the individual
peaks are determined on the basis of the values in the
literature.
What you can learn about
- Decay series
- Radioactive equilibrium
- Isotopic properties
- Decay energy
- Particle energy
- Potential well model of the atomic nucleus
- Tunnel effect
- Geiger-Nuttal law
- Semiconductor
- Barrier layer