RE: blue flash and criticality

["Tom Savin" <lexicon@hotbot.com>]

Thanks Steve and Franz and among others,

My question now is, IF, you had a camera, and the source of criticality was shielded from the camera's angle, in other words that the source was going away from the camera instead of at it, and you you were able to establish the original spectrum from long distance face on photography, would it be red shifted going away?  I believe this to be a significant question when considering water vs air vs vacuum.  I was originally curious about this and made a bit fun - but really has anyone really looked at this?  It seems that this has not been addressed in the literature. This experiment would yeild a definitive answer.

                I truly enjoy everyone's input!

                     Tom
--

On Thu, 9 Nov 2000 15:28:40    Sugarman, Steve wrote:
>This is as good a basic explanation as I have found for Cherenkov radiation.
>It came from the Univ. of Missouri-Rolla (http://www.umr.edu) website.
>There is also a pretty good picture of their reactor, complete with the
>"blue glow."  
>
>"...While no particle can exceed the speed of light in a vacuum (3.0E+8
>m/sec), it is possible for a particle to travel faster than light in certain
>mediums, such as water. The speed of light in a particular medium is related
>to the speed of light in a vacuum and by the index of refraction. Water has
>an index of refraction of approx. 1.3; thus the speed of light in water is
>2.3E+8 m/s. Beta particles with kinetic energies in excess of 0.26 MeV
>travel at speeds in excess of 2.3E+8 m/s.
>
>When the charged beta particle moves through water it tends to "POLARIZE"
>(or orient) the water molecules in a direction adjacent to its path thus
>"DISTORTING" the local electric charge distribution. After the beta particle
>has passed, the molecules realign themselves in their original, random
>charge distribution. A pulse of electromagnetic radiation in the form of
>BLUE LIGHT is emitted as a result of this "REORIENTATION". When the speed of
>the beta particle is less than the speed of the light, the pulses tend to
>"CANCEL" themselves by destructive interference; however, when the speed of
>the beta particle is greater than the speed of light then the light pulses
>are "AMPLIFIED" through constructive interference. The phenomenon is
>analogous to the acoustic "SONIC BOOM" observed when an object exceeds the
>speed of sound in air.
>
>The intensity of the blue glow is directly proportional to the number of
>fissions occurring and the reactor power level. This property is utilized in
>Cherenkov detectors that measure the magnitude of Cherenkov radiation
>produced in a detector made of Lucite."
>
>Interestingly, the source  that was involved in the Goiania, Brazil Accident
>in 1987 (approx. 1375 Ci Cs-137) appeared to glow after the capsule was
>breached, but the color was greener than it was blue.  The general consensus
>is that this was Cherenkov radiation due to at some time after the capsule
>was breached, enough ambient moisture was absorbed by the cesium chloride
>salt source to allow this phenomenon to be seen, but the moisture levels
>affected the color of the "glow".
>
>Steve Sugarman
>Health Physicist, REAC/TS
>sugarmas@orau.gov
>
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