deletions | additions       diff --git a/sectionNeon__A_comme.tex b/sectionNeon__A_comme.tex  index 30745be..eeeb48a 100644  --- a/sectionNeon__A_comme.tex  +++ b/sectionNeon__A_comme.tex 
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\section{Experiments with a Neon Tube}  A commercial apparatus containing Neon atoms was used. The tube contained a cathode, two mesh-type control grids ($G_{1}$ and $G_{2}$) , and a collector electrode. The distance between grid 1 and grid 2 was about 5mm. The distance between the cathode and grid 1 and the distance between the collector electrode and grid 2 was approximately 2 mm. The cathode was kept at a constant current ($135 mA$), and grid 1 and grid 2 were kept at constant voltages. ($4.8V$ and $11.6V$ respectively.) The anode current, (converted into $V_{out}$), oscillates as accelerating voltage $U_{2}$ increases. The final Franck-Hertz curve for Neon shown in Figure 3 contained 3 dips of the anode current. Close observation of the peaks and dips indicates a systematic substructure, which can be explained by the excitation of additional energy levels of neon above the lowest excited state. Figure 2 3  taken from \cite{Rapior_2006} shows 14 excited levels of Neon divided into two groups, $E_{a1}$ and $E_{a2}$. If the mean free path is significant, electrons will gain addition energy over $\lambda$, and will excite states in $E_{a2}$ and well as exciting the lowest energy level.