The stress relaxation (creep) rate of Mu2e straw tubes

We report on the material relaxation properties of the Mu2e straw tubes measured over a period of about 5 years under two conditions. One is a fixed tension condition: two straw tubes are under a constant tension, and the lengthening of the tubes is measured as a function of time. The other is a fixed length condition: the length of four straw tubes with different initial tensions is fixed, and the tension in the tubes is measured. For the latter case, a scaling behavior appears when the ratio of the tension to the initial tension of the four straws is plotted as a function of time. In both cases, we find that the creep rates can be well parameterized with a logarithmic function of time elapsed. This implies that, for example, the amount of creep from day 20 to 200 is the same as between day 200 and 2000.

Duke Scholars

Author Seog Oh Physics