When the electrons in a cathode ray tube collide with the glass, they decelerate rapidly. The radiation emitted by the electrons is called Bremsstrahlung or braking radiation.
In 1895, Wilhelm Röntgen discovered that a beam of cathode rays...
How could the fluorescence of the glass in a Crooke's tube generate x-rays? This was the question Henri Becquerel addressed in 1896. His experiments with fluorescence in uranium salts and subsequent discovery of radioactivity are recreated in...
Radiations originating from atomic and nuclear processes are classified into four types:
charged particulate radiation consisting of
1. heavy charged particles (α)
2. fast electrons (β)
uncharged radiation consisting of
3. electromagnetic...
The interactions of the various radiations with matter are unique and determine their penetrability through matter and, consequently, the type and amount of shielding needed for radiation protection. Being electrically neutral, the...
Gamma rays are electromagnetic radiations which we detect as quanta of energy or photons. When the radioactive source is confined so that it acts as a point source, the diminution in the number of photons incident on a given area is such...
β-rays emanating from a radioactive isotope are deflected from their straight line paths by a magnetic field.
90Sr/90Y, a "pure" beta-minus source, emits a continuous spectrum of fast electrons up to a maximum energy of 0.546/2...
Observe the decay of airborne radionuclides with a Geiger counter and computer. (OK, it's not new since we've been doing the experiment for 20 years...we just neglected adding it to our list.)
Filtering dust particles from the air is a...
Gamma ray spectroscopy is used to detect the minute amount of radioactive potassium-40 present in the human body. Using a NaI(Tl) scintillation detector in conjunction with a multichannel pulse-height analyzer (PHA), 1.46 MeV gammas...
The very first determination of a half-life for a radioactive decay was made by Rutherford. 1 In a study of the properties of thorium emanation, he found that the intensity of the radiations fell off with time in a geometric progression...
One of the more important discoveries in modern physics is the production of isotopes (both radioactive and stable) by the capture of neutrons. 1 In this experiment the bombardment of silver by thermalized neutrons produces short lived...
The path of a single charged particle can be made visible in cooled supersaturated air/alcohol vapor.
The cloud chamber was developed by C.T.R. Wilson at the turn of the century (he received the Nobel Prize in 1927 for his...
We have designed and built our own cosmic ray telescope (a.k.a. spark chamber). Unlike the old one, this one works reliably, is larger, and makes for a great demo.
In the 1960's and '70s, spark chambers were commonly used as detectors in particle physics...
