I repeated the analysis for bulk and shear losses described in an early elog entry, with the same coating, but after annealing at 500C for 9 hours.
The COMSOL model is the same as before, so the dilution factors are the same, except that this time I could measure a few more modes at high frequency:
As in the previous analysis, I fitted four different models:
1) one single loss angle for both bulk and shear, constant in frequency
2) one single loss angle for both bulk and shear, linear in frequency
3) separate bulk and shear loss angles, constant
4) separate bulk and shear loss angles, linear in frequency
The data strongly favor the last model: two loss angles for shear and bulk, linearly dependent on frequency (Bayes factor 22.7 for the second best model, which is the frequency dependent single loss angle).
The results are below.
Single constant loss angle
Single loss angle, linearly dependent on frequency
Bulk and shear loss angles, constant
Bulk and shear loss angles, linearly dependent on frequency
