protons at Fermilab

logistic_guy

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What is the wavelength, and maximum resolving power attainable, using 900\displaystyle 900-GeV\displaystyle \text{GeV} protons at Fermilab?
 
What is the wavelength, and maximum resolving power attainable, using 900\displaystyle 900-GeV\displaystyle \text{GeV} protons at Fermilab?
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Please share your work/thoughts about this problem
 
We first need to calculate the total energy.

E=K+mc2\displaystyle E = K + mc^2

where mc2\displaystyle mc^2 is the rest energy of the proton.

Since the rest energy is very small compared to the kinetic energy, we can safely ignore it. (You can calculate it if you want. It will not affect the answer!)

Then, we have:

E=K=900 GeV\displaystyle E = K = 900 \ \text{GeV}

The momentum formula is p=Ec\displaystyle p = \frac{E}{c} and the wavelength formula is λ=hp\displaystyle \lambda = \frac{h}{p}, then

λ=hcE\displaystyle \lambda = \frac{hc}{E}

where h\displaystyle h is Planck's Constant: h=6.626×1034 Js\displaystyle h = 6.626 \times 10^{-34} \ \text{J} \cdot \text{s}

And hc=1.24×1012 MeVm\displaystyle hc = 1.24 \times 10^{-12} \ \text{MeV} \cdot \text{m} (I will derive this result in future posts.)

Then, the wavelength is:

λ=1.24×1012 MeVm900 GeV×GeV103 MeV=1.38×1018 m\displaystyle \lambda = \frac{1.24 \times 10^{-12} \ \text{MeV} \cdot \text{m}}{900 \ \text{GeV}} \times \frac{\text{GeV}}{10^3 \ \text{MeV}} = \textcolor{blue}{1.38 \times 10^{-18} \ \text{m}}

The power is given by:

P=cEλ=(299792458 m/s)(900×109 eV)1.38×1018 m×1.6×1019 JeV=3.13×1019 W\displaystyle P = \frac{cE}{\lambda} = \frac{(299792458 \ \text{m/s})(900 \times 10^{9} \ \text{eV})}{1.38 \times 10^{-18} \ \text{m}} \times \frac{1.6 \times 10^{-19} \ \text{J}}{\text{eV}} = \textcolor{blue}{3.13 \times 10^{19} \ \text{W}}
 
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