# TOF Light Attenuation

### TOF Light Attenuation

Light attenuation in the TOF paddles are investigated

A closer look at the attenuation of light in the TOF paddles suggests the use of two attenuation lengths rather then just one. This gives a much better description over the full length of the paddles. The following figure shows a fit to the MPV positions of paddle 44 as a function of position along the paddle. The red curve shows a fit with two free parameters for the two attenuation lengths and one overall scale factor. The cyan curve shows a fit to the data from 1/3 to 2/3 along the paddle with a single attenuation length parameter. At FSU the attenuation length was determined with measurements at these two points along the paddle.

The attenuation length found at FSU can be seen here: FSU attenuation length. The mean is about 300cm. The mean of a single attenuation parameter from fits to the data between 1/3 and 2/3 is about 225cm. The mean values from the fits with two attenuation parameters are about 75cm and 485cm respectively.