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Acoustic properties of the phantom. Speed of sound c in m/s (average ± one standard deviation from four measurements), attenuation coefficient α in dB/cm at 2.5MHz, parameters from a power fit and a linear fit to α versus frequency.
| c (m/s) | α ( 2.5MHz) (dB/cm) | Power fit α=α0fn | Linear fit α=α0f | ||
|---|---|---|---|---|---|
| α0(dB/cm-MHzn) | n | α0(dB/cm-MHz) | |||
| Background (reference) | 1544± 1 | 1.06 | 0.36 | 1.17 | 0.51 |
| Sphere A | 1538± 3 | 2.51 | 0.97 | 1.02 | 1.02 |
| Sphere B | 1531± 2 | 3.57 | 1.33 | 1.08 | 1.58 |
