Search results
Results from the WOW.Com Content Network
Although collimators improve resolution, they also reduce intensity by blocking incoming radiation, which is undesirable for remote sensing instruments that require high sensitivity. For this reason, the gamma ray spectrometer on the Mars Odyssey is a non-collimated instrument. Most lead collimators let less than 1% of incident photons through.
The term collimated may also be applied to particle beams – a collimated particle beam – where typically shielding blocks of high density materials (such as lead, bismuth alloys, etc.) may be used to absorb or block peripheral particles from a desired forward direction, especially a sequence of such absorbing collimators.
MLC shape of an X-MLCs. A multileaf collimator (MLC) is a Collimator or beam-limiting device that is made of individual "leaves" of a high atomic numbered material, usually tungsten, that can move independently in and out of the path of a radiotherapy beam in order to shape it and vary its intensity.
The A3, or Modulation Collimator (MC) instrument, provided high-precision positions of X-ray sources, accurate enough to permit follow-up observations to identify optical and radio counterparts. It was provided by the Center for Astrophysics ( Smithsonian Astrophysical Observatory and the Harvard College Observatory , SAO/HCO). [ 5 ]
As the inventor of the floating collimator, Kater rendered a service to practical astronomy. [3] He also published memoirs [ 4 ] on British standards of length and mass ; and in 1832 he published an account of his work on verifying the Russian standards of length.
William Herbert Rollins (June 19, 1852 - 1929) was an American scientist, inventor, and dentist. He was a pioneer in radiation protection.Many of his inventions and investigations in medical radiography and photography have been ranked in importance with those of Thomas A. Edison, Elihu Thomson, and William J. Morton.
Discover the best free online games at AOL.com - Play board, card, casino, puzzle and many more online games while chatting with others in real-time.
A floating collimator consists of a rectangular box containing mercury, with a piece of cast iron floating on top. The cast-iron is about twelve inches long, four broad, and half an inch thick, having two short uprights or Y's of equal height on top.