blade-shaped proton-beam range modulator wheel
Date: 1980-1984
Inventory Number: 2003-1-0275
Classification: Range Modulator
Maker: Harvard Cyclotron Laboratory (1937 - 2002)
Inventor: Andreas Koehler (1930 - 2015)
Cultural Region:
Place of Origin:
Dimensions:
66.5 x 83 x 9.5 cm (26 3/16 x 32 11/16 x 3 3/4 in.)
Material:
Description:
This range modulator consists of stacked acrylic arranged to form 11 steps, thereby changing the extent in depth of the plastic by about 7 cm. The modulator wheel has four pattern repeats--two on each side of the blade--as the stacked acrylic rises and falls in height. The rim of the wheel is spray-painted black.
This range modulator would spin at 3 rotations / second. The proton beam would be perpendicular to it. As the propellor spun in front of the beam, the beam would penetrate its target more or less in depth depending on the thickness of the plastic at the time in front of the beam. The range of penetration permitted by the modulator was known as the "extent-in-depth."
This range modulator would spin at 3 rotations / second. The proton beam would be perpendicular to it. As the propellor spun in front of the beam, the beam would penetrate its target more or less in depth depending on the thickness of the plastic at the time in front of the beam. The range of penetration permitted by the modulator was known as the "extent-in-depth."
In Collection(s)
Signedunsigned
FunctionThe range modulator was used to control the extant-in-depth that a proton beam would penetrate its target.
Historical AttributesThis range modulator was used at the Harvard Cyclotron Laboratory by Andreas Koehler for his experiments on the detection of osteoporosis, in which he used a live cat as a target for the proton beam.
There was a whole library of range modulators at the cyclotron for use in treating cancerous tumors as well. The modulators governed the extent-in-depth that the proton beam would go in and out of a tumor.
There was a whole library of range modulators at the cyclotron for use in treating cancerous tumors as well. The modulators governed the extent-in-depth that the proton beam would go in and out of a tumor.
ProvenanceFrom the Harvard Cyclotron Laboratory, 2002.