a).Disc and Laminated Sources

a).Disc and Laminated Sources -

Technical Data

NUCLEONIX SYSTEMS, IS AN AUTHORISED INTERNATIONAL DEALER by SPECTRUM TECHNIQUES – USA to supply these reference, exempt limit sources. Both uncalibrated & calibrated reference sources with certificate can be offered.Disc sources are available in 1″ and 2″ diameter plastic disc with the 1″ being standard and other sizes on special order.

The PO-210 alpha source is of open window construction with the source material bonded to the surface of a silver foil mounted in the recess of the plastic disc. This design yields excellent emission of alpha particles without window losses.

Plastic laminates provide a convenient alternative packaging being easy to handle and store. The standard laminates have a transmission window of 0.005″ and produce minimum attenuation for photons and higher energy beta particles.


Now the C14, FE55 and Po210 sources have a thin, aluminized Mylar window. Order as, for example, C14LMW – Laminated Mylar Window

Two sizes are available, 3.75″x2.25″, and a 1″ diameter circular disc. Other sizes are available; just let us know and we will send you a quote. Low energy x-ray, beta and alpha sources can be produced with a 80 µgm/cm2 aluminized Mylar window offering excellent transmission for Fe-55, C-14 and Po-210.


GM Resolving Time Set This set is used for determining the resolving time of GM Counters. It consists of three half discs, two of which contain 5 microcuries of Tl-204 plus a third half disc with no activity. The count-rate of each half disc plus the blank (to maintain constant geometry) is measured and then both active half discs are combined for a measurement with high count-rate. The counting loss may now be calculated by adding the rates from each half disc and comparing the result to the count-rate with both halves combined.


The RSS-3 contains 1 each Po-210, Sr-90 and Co-60 emitting a range of alpha, beta and gamma radiation’s. This set is ideal for demonstration and introductory nuclear labs covering basic characteristics of radiation. The Co-60 is 1.0 uCi and the Po-210 and Sr-90 are 0.1 uCi activity.


Containing 1 each Cs-137, Co-60, Sr-90, Tl-204 and Po-210, the RSS-5 provides a wide of alpha, beta and gamma emissions making it a popular choice for nuclear science instruction The set contains two beta emitters, two beta/gamma emitters and one alpha source for in-depth studies of radiation. The Cs-137 is 5 uCi, the Po-210 and Sr-90 are 0.1 uCi activity and the Co-60 and Tl-204 are both 1 uCi.


Designed for gamma spectroscopy, the RSS-8 contains eight different gamma emitting isotopes covering the entire energy range from 32 to 1333 keV. Also included in the set is a mixed source of Cs-137 and Zn-65 which students may use to identify an “unknown” isotope. The set consists of Ba-133, Cd-109, Co-57, Co-60, Cs-137, Mn-54. Na-22 and Cs/Zn. Source activities are all 1 uCi, except the Cs/Zn source, which is 0.5 uCi Cs and 1 uCi Zn. Calibrated Gamma Reference Source Set (RSS-8) with certificate can be offered at extra cost.


Due its relatively short half-life, the Po-210 alpha source must be replaced on a regular basis. Currently this is the only alpha emitting material available as a NRC Exempt Quantity which may be held without a radioactive material license.

Radioisotope sources are available individually or packaged as sets of three, five, and eight in convenient storage boxes. These items are exempt sources and of nominal activity to provide a safe, yet inexpensive supply of radioactive material for educational and commercial use.

When shipping or storing multiple gamma sources, to reduce reduce radiation levels we recommend using Lead Shields. Standard individual sources for alpha, beta and gamma emissions are available in the following isotopes.


Activity Half-life Emissions Energies (keV)
Ba133S1 1uCi. 10.7 years Gamma 81.0, 276.3, 303.7, 355.9, 383.7
C14S10 10uCi. 5730 years Beta β156.5
Cd109S1 1uCi. 453 days Gamma 88.0
Co57S1 1uCi. 270 days Gamma 122.1, 136.4
Co60S1 1uCi. 5.27 years Gamma, Beta 1173.2, 1332.5, β317.9
Cs137S.2 0.2uCi. 30.1 years Gamma, Beta 32, 661.6, β511.6, β1173.2
Cs137S.5 0.5uCi. 30.1 years Gamma, Beta 32, 661.6, β511.6, β1173.2
Cs137S1 1uCi. 30.1 years Gamma, Beta 32, 661.6, β511.6, β1173.2
Cs137S5 5uCi. 30.1 years Gamma, Beta 32, 661.6, β511.6, β1173.2
Cs/ZnS 1uCi. Mixed “Unknown” 32, 661.6, 1115.5
Eu152S1 1uCi. 13.5 Years Gamma, Beta Multiple energies
Fe55S100 100uCi. 2.73 years X-ray, Beta 5.9, 6.5, β231.4
Mn54S1 1uCi. 312 days Gamma, Beta 834.8, β542.2
Na22S1 1uCi. 2.6 years Gamma 1274.5, 511
Po210S 0.1uCi. 138 days Alpha 5304.4
Sr90S 0.1uCi. 28.8 years Beta β546
Tl204S1 1uCi. 3.78 years Beta β763.7
Zn65S1 1uCi. 244 days Gamma, Beta 1115.6, β236.34 β1351.9