I was conducting an experiment, and we had to use a radioactive source and a Geigor counter, in conjunction with aluminium plates. Using the data we produced we had to graph an absorption curve and obtain a value for the mass absorption coefficient of aluminium. Then we had to compare this value with the accepted value for the mass absorption coefficient of aluminium. Would anyone here know what the accepted value is, as I can't seem to locate it on Google, or anywhere else. Thank you.