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Comment: Bremsstrahlung effect? (Score 2, Interesting) 70

by cachimaster (#48623899) Attached to: Terrestrial Gamma Ray Bursts Very Common

Xrays produced by the Bremsstrahlung effect are proportional to the voltage of free-electrons hitting an atom. That is, a 30kV electron would produce X-ray light with a spectrum centered in 30kV.

Rays have millions of volts and should be expected to produce X-rays of mega-electronvolts energy, this is gamma-ray energy levels.

But Bremsstrahlung needs vacuum, so I probably don't know what I'm talking about.

Comment: Opera Developer (Score 0) 181

Firefox is dog slow in Ubuntu box (Core I5!) always taking 20%-30% cpu.
Chrome, not much better. Just tried Opera Developer (chromium based I believe) and the difference is abysmal. 0% cpu at idle, fast as lightning, I installed lots of plugins into Opera and it still it consumes no CPU. Why Firefox or chrome can't be like this?

Comment: Re:More like Gamma-ray devices (Score 2) 113

by cachimaster (#44989879) Attached to: 3mm Inexpensive Chip Revolutionizes Electron Accelerators

Fair enough, just two questions:
1) An electron hitting an atom will produce photons with the same energy via the Bremsstrahlung effect. As electrons will hit atoms sometimes, 300 MeV electrons means you will have 300 MeV photons, right?
2) How much energy a photon needs to transmute an atom? I believe it's lower than 300 MeV (but as a commenter said, it's 300 MeV *per meter* so really you need a lot of those devices chained together for them to become dangerous, I guess)

The algorithm for finding the longest path in a graph is NP-complete. For you systems people, that means it's *real slow*. -- Bart Miller

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