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0 pointsPatrick_Devine12y ago0 comments

and also:

"The electrons fed into it were first sped up using a midsized standard accelerator, so when they arrived at the glass accelerator they were already travelling at 99.86% of the speed of light, or 60m electron-volts..."

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2 comments · 1 top-level

cnvogel12y ago· 1 in thread

And again, in the complete nonsensical quest of describing particle energies by many nines in 99.999999..% of the speed of light, the proper math falls down, 99.86% c is ~10 MeV, 60 MeV is about 99.996% c, but IT'S COMPLETELY MEANINGLESS!

Nevertheless...

Here's a handy online-tool to calculate the speed of a particle accellerated in a electric field (enter 60000 kV to get the values for the 60 MeV electron):

http://www.ou.edu/research/electron/bmz5364/calc-kv.html

Or calculate it yourself: E = E₀ / √( 1 - β²) with E₀ being the rest-energy of the particle (511 keV in the case of the electron) and β being the velocity relative to the speed of light.

At 99.86% of the speed of light, an electron will have a total (rest-mass + acquired energy by accelleration) energy of about 10 MeV:

    (in python, energies in keV)
    >>> 511. / math.sqrt( 1 - .9986 ** 2 )
    9660.374008193809

nxpnsv12y ago

...and of course to replicate lhc they'd need to reach 3.5 TeV at high luminosity. let's just say they are not ready for this quite yet...

EDIT: (in 2011, then 4 TeV and next time they run 7 TeV)

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