Table 4
Rotation model parameters of Betelgeuse.
| Model | PA | νeqsini | νexp |
|
σ res |
| (°) | (km s-1) | (km s-1) | (km s-1) | ||
|
|
|||||
| 28SiO(ν= 2, J = 8−7) | |||||
| Solid | 48.0 ± 1.1 | 5.47 ± 0.10 | − | 20.7 | 1.44 |
| Solid+Exp | 47.6 ± 1.1 | 5.56 ± 0.10 | +0.69 ± 0.08 | 18.8 | 1.41 |
|
|
|||||
| 12CO(ν= 0, J = 3−2) | |||||
| Solid | 49.5 ± 1.0 | 4.82 ± 0.08 | − | 12.5 | 1.13 |
| Solid+Exp | 47.9 ± 1.0 | 4.76 ± 0.08 | +0.60 ± 0.06 | 11.1 | 1.12 |
|
|
|||||
| 28SiO(ν= 1, J = 8−7) | |||||
| Solid | 51.9 ± 1.3 | 5.81 ± 0.13 | − | 35.8 | 1.39 |
| Solid+Exp | 50.6 ± 1.0 | 5.73 ± 0.10 | +1.75 ± 0.08 | 20.6 | 1.34 |
|
|
|||||
| 29SiO(ν= 0, J = 8−7) | |||||
| Solid | 45.5 ± 1.0 | 5.68 ± 0.09 | − | 18.9 | 1.34 |
| Solid+Exp | 45.8 ± 1.0 | 5.68 ± 0.09 | −0.21 ± 0.08 | 18.7 | 1.34 |
Notes. The position angle of the polar axis PA is in degrees east of north. The listed error bars are scaled by 
to account for the residual dispersion of the fit. They do not comprise the systematic uncertainty that we estimate to ± 3.3° for the position angle of the polar axis PA and ± 0.20 km s-1 for the projected rotation velocity νeqsini (see Sect. 3.5 for details).