Negative absorption coefficient in muon absorption?

[Ahmed Abdalla]

Homework Statement

I am conducting an experiment where I am interested in finding the absorption coefficient of different materials as muons pass through them. My data was all well until I realized more muons were measured AFTER they passed through one of the materials, which makes no sense because how can you measure more of something after it was absorbed through a material. I used Lambert’s law to solve for the coefficient of absorption of the materials and it was not surprising that for this particular measurement I got a negative value, which again is impossible. I can explain that due to a bad snow storm during measurements more muons may have been measured compared to when they were measured without any metrial (my control group which was on an average weather) but when I present my data this just seems crazy. I was wondering if there is a way I can correct it in a sense.

 

[gleem]

Could you describe and give the details of your experimental setup?