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Summary

Description Mean Free Path in cm, for photons in energy range from 1 keV to 20 MeV for Elements Z = 1 to 100. Based on data from [1]. The discontinuities are due to low density of gas elements. Six bands correspond to neighborhoods of six noble gases. Also shown are locations of photons absorption edges (and not Compton edges as mentioned in the comments from the Matlab code).
Date 10/04/2007
Source Own work
Author Jarekt
 
This diagram was created with MATLAB.

The image was generated using the following MATLAB code, with help of external library PhotonAtenuattion2:

%% Plot mean free path of photons in different media
% Plot as function of energy and atomic number of media/element
figure
Z = 1:99;  % elements with Z in 1-100 range - number of columns
nr = 500;   % number of rows to use in the plot
E = logspace(log10(0.001), log10(20), 500);  % define energy grid
mfp = PhotonAttenuation(Z, E, 'mean free path');
colormap(jet(128)) % use hi-res color palette
imagesc(log10(mfp)); 
grid on;
axis xy; % put small numbers on y axis on the bottom
title('Mean free path of photons in different media (in cm)');
xlabel('Atomic number of elements');
ylabel('Energy in MeV');
% Add X-Axis 
EPos = [6 16 26 35 47 55 65 74 82 94];   % define array to store label location
ELab = { '6-C','16-S','26-Fe','35-Br','47-Ag','55-Cs','65-Tb','74-W','82-Pb','94-Pu'}; %Define Energy labels for y-axis
set(gca,'XTick'     ,EPos);
set(gca,'XTickLabel',ELab);
% Add Y-Axis
ELab = [0.001 0.003 0.01 0.03 0.1 0.3 1 3 10]; %Define Energy labels for y-axis
EPos = size(ELab);   % define array to store label location
for i=1:length(ELab), [tmp EPos(i)]=min(abs(E-ELab(i))); end
set(gca,'YTick'     ,EPos);
set(gca,'YTickLabel',ELab);
% add Colorbar
cbar_axes = colorbar;
set(cbar_axes,'YTick'     ,     -5:5 ); % The image is a log10 of the MAC ...
set(cbar_axes,'YTickLabel',10.^(-5:5)); % ... so add proper labels
hold on
% Add Compton Edges to the plot
[tmp, CEdge] = PhotonAttenuationQ(Z, E);
ed = accumarray([CEdge(:,1),CEdge(:,2)],CEdge(:,3)); % get per element energies of 14 compton edges 
ed = 500*(log(ed')-log(0.001))/(log(20)-log(0.001)); % convert energy to row numbers of the image
K=plot(ed(:,1)    ,'m','LineWidth',3); %Plot K Compton edge
L=plot(ed(:, 2: 4),'r','LineWidth',2); %Plot 3 L Compton edges
M=plot(ed(:, 5: 9),'g','LineWidth',2); %Plot 5 M Compton edges
N=plot(ed(:,10:end),'y','LineWidth',2); %Plot first 5 N Compton edges
legend([K(1),L(1),M(1),N(1)], {'K','L','M','N'}, 'Location', 'NorthEast');

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Date/TimeThumbnailDimensionsUserComment
current03:19, 15 August 2017Thumbnail for version as of 03:19, 15 August 20171,097 × 855 (36 KB)Mikhail Ryazanovrm. excessive caps, crop top margin
23:09, 2 October 2016Thumbnail for version as of 23:09, 2 October 20161,097 × 879 (31 KB)CmdrjamesonCompressed with pngout. Reduced by 70kB (69% decrease).
03:41, 5 October 2007Thumbnail for version as of 03:41, 5 October 20071,097 × 879 (101 KB)Jarektbetter crop
03:38, 5 October 2007Thumbnail for version as of 03:38, 5 October 20071,280 × 929 (56 KB)Jarekt{{Information |Description='''Mean Free Path''' for photons in energy range from 1 keV to 20 MeV for Elements Z = 1 to 100. Based on [http://physics.nist.gov/PhysRefData/XrayNoteB.html]. Also shown are locations of Compton edges. |Source=self-made |Date=1

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