Parameters for β Vir (2017 April 3–24) and θ Dra ( 2017 April 6–24) derived from the maximum-entropy image reconstructions, wind modelling inputs, and magnetic cycle determination using GLS periodogram of S-index. All parameters are from this work except where marked. ZDI determined parameters use Stokes V data except where marked and include χ2 minimization and Ωeq versus dΩ grid search.
| Parameter . | β Vir . | θ Dra . |
|---|---|---|
| zdi determined parameters | ||
| Inclination (deg) (χ2 min) | 36 ± 2 | 37 ± 2 |
| vsin i (km s−1) (χ2 min) | 6.1 ± 2.6a | 28.1 ± 0.2 |
| Prot (d) (χ2 min) | 9.2 ± 0.2b | 2.88 ± 0.02 |
| Prot (d) (grid search) | 9.1 ± 0.4 | 2.88 ± 0.02 |
| dΩ (rad d−1) (χ2 min) | 0.21 ± 0.02 | 0.18 ± 0.02 |
| dΩ (rad d−1) (grid search) | 0.23 ± 0.09 | 0.18 ± 0.03 |
| Eq-pole lap time (d) | |$29.9^{+3.1}_{-2.6}$| | |$34.9^{+4.4}_{-3.9}$| |
| S-index cycle | ||
| No. observations | 49 | 105 |
| Observation baseline (d) | 68 | 73 |
| Cycle length (d) | 83 ± 14 | 43 ± 2 |
| No. cycles observed | 0.8 | 1.7 |
| FAP | <10−3 | <10−9 |
| Wind model input | ||
| Stellar mass (M⊙)c | 1.13 | 1.17 |
| Stellar radius (R⊙)c | 1.75 | 2.67 |
| Wind model parameter | Value | |
| Chromospheric base temperature, Tchr | |$5 \times 10^{4}\, \mathrm{K}$| | |
| Chromospheric base density, nchr | |$2 \times 10^{17}\, \mathrm{m}^{-3}$| | |
| Poynting flux-to-field ratio, |$\Pi _{\small {A}}/B$| | |$1.1 \times 10^{6} \, \mathrm{Watt\, m^{-2}\, T^{-1}}$| | |
| Turbulence trans. corr. length, |$L_\perp \sqrt{B}$| | |$1.5 \times 10^{5}\, \mathrm{m\, T^{1/2}}$| | |
| Coulomb logarithm, |$\Lambda _{\small {C}}$| | 20 | |
| Parameter . | β Vir . | θ Dra . |
|---|---|---|
| zdi determined parameters | ||
| Inclination (deg) (χ2 min) | 36 ± 2 | 37 ± 2 |
| vsin i (km s−1) (χ2 min) | 6.1 ± 2.6a | 28.1 ± 0.2 |
| Prot (d) (χ2 min) | 9.2 ± 0.2b | 2.88 ± 0.02 |
| Prot (d) (grid search) | 9.1 ± 0.4 | 2.88 ± 0.02 |
| dΩ (rad d−1) (χ2 min) | 0.21 ± 0.02 | 0.18 ± 0.02 |
| dΩ (rad d−1) (grid search) | 0.23 ± 0.09 | 0.18 ± 0.03 |
| Eq-pole lap time (d) | |$29.9^{+3.1}_{-2.6}$| | |$34.9^{+4.4}_{-3.9}$| |
| S-index cycle | ||
| No. observations | 49 | 105 |
| Observation baseline (d) | 68 | 73 |
| Cycle length (d) | 83 ± 14 | 43 ± 2 |
| No. cycles observed | 0.8 | 1.7 |
| FAP | <10−3 | <10−9 |
| Wind model input | ||
| Stellar mass (M⊙)c | 1.13 | 1.17 |
| Stellar radius (R⊙)c | 1.75 | 2.67 |
| Wind model parameter | Value | |
| Chromospheric base temperature, Tchr | |$5 \times 10^{4}\, \mathrm{K}$| | |
| Chromospheric base density, nchr | |$2 \times 10^{17}\, \mathrm{m}^{-3}$| | |
| Poynting flux-to-field ratio, |$\Pi _{\small {A}}/B$| | |$1.1 \times 10^{6} \, \mathrm{Watt\, m^{-2}\, T^{-1}}$| | |
| Turbulence trans. corr. length, |$L_\perp \sqrt{B}$| | |$1.5 \times 10^{5}\, \mathrm{m\, T^{1/2}}$| | |
| Coulomb logarithm, |$\Lambda _{\small {C}}$| | 20 | |
vsin i value taken from Glebocki & Gnacinski (2005) since the χ2 minimization did not produce a well-defined minimum. bProt value of 9.2 d used in final maps. cStassun et al. (2019).
Parameters for β Vir (2017 April 3–24) and θ Dra ( 2017 April 6–24) derived from the maximum-entropy image reconstructions, wind modelling inputs, and magnetic cycle determination using GLS periodogram of S-index. All parameters are from this work except where marked. ZDI determined parameters use Stokes V data except where marked and include χ2 minimization and Ωeq versus dΩ grid search.
| Parameter . | β Vir . | θ Dra . |
|---|---|---|
| zdi determined parameters | ||
| Inclination (deg) (χ2 min) | 36 ± 2 | 37 ± 2 |
| vsin i (km s−1) (χ2 min) | 6.1 ± 2.6a | 28.1 ± 0.2 |
| Prot (d) (χ2 min) | 9.2 ± 0.2b | 2.88 ± 0.02 |
| Prot (d) (grid search) | 9.1 ± 0.4 | 2.88 ± 0.02 |
| dΩ (rad d−1) (χ2 min) | 0.21 ± 0.02 | 0.18 ± 0.02 |
| dΩ (rad d−1) (grid search) | 0.23 ± 0.09 | 0.18 ± 0.03 |
| Eq-pole lap time (d) | |$29.9^{+3.1}_{-2.6}$| | |$34.9^{+4.4}_{-3.9}$| |
| S-index cycle | ||
| No. observations | 49 | 105 |
| Observation baseline (d) | 68 | 73 |
| Cycle length (d) | 83 ± 14 | 43 ± 2 |
| No. cycles observed | 0.8 | 1.7 |
| FAP | <10−3 | <10−9 |
| Wind model input | ||
| Stellar mass (M⊙)c | 1.13 | 1.17 |
| Stellar radius (R⊙)c | 1.75 | 2.67 |
| Wind model parameter | Value | |
| Chromospheric base temperature, Tchr | |$5 \times 10^{4}\, \mathrm{K}$| | |
| Chromospheric base density, nchr | |$2 \times 10^{17}\, \mathrm{m}^{-3}$| | |
| Poynting flux-to-field ratio, |$\Pi _{\small {A}}/B$| | |$1.1 \times 10^{6} \, \mathrm{Watt\, m^{-2}\, T^{-1}}$| | |
| Turbulence trans. corr. length, |$L_\perp \sqrt{B}$| | |$1.5 \times 10^{5}\, \mathrm{m\, T^{1/2}}$| | |
| Coulomb logarithm, |$\Lambda _{\small {C}}$| | 20 | |
| Parameter . | β Vir . | θ Dra . |
|---|---|---|
| zdi determined parameters | ||
| Inclination (deg) (χ2 min) | 36 ± 2 | 37 ± 2 |
| vsin i (km s−1) (χ2 min) | 6.1 ± 2.6a | 28.1 ± 0.2 |
| Prot (d) (χ2 min) | 9.2 ± 0.2b | 2.88 ± 0.02 |
| Prot (d) (grid search) | 9.1 ± 0.4 | 2.88 ± 0.02 |
| dΩ (rad d−1) (χ2 min) | 0.21 ± 0.02 | 0.18 ± 0.02 |
| dΩ (rad d−1) (grid search) | 0.23 ± 0.09 | 0.18 ± 0.03 |
| Eq-pole lap time (d) | |$29.9^{+3.1}_{-2.6}$| | |$34.9^{+4.4}_{-3.9}$| |
| S-index cycle | ||
| No. observations | 49 | 105 |
| Observation baseline (d) | 68 | 73 |
| Cycle length (d) | 83 ± 14 | 43 ± 2 |
| No. cycles observed | 0.8 | 1.7 |
| FAP | <10−3 | <10−9 |
| Wind model input | ||
| Stellar mass (M⊙)c | 1.13 | 1.17 |
| Stellar radius (R⊙)c | 1.75 | 2.67 |
| Wind model parameter | Value | |
| Chromospheric base temperature, Tchr | |$5 \times 10^{4}\, \mathrm{K}$| | |
| Chromospheric base density, nchr | |$2 \times 10^{17}\, \mathrm{m}^{-3}$| | |
| Poynting flux-to-field ratio, |$\Pi _{\small {A}}/B$| | |$1.1 \times 10^{6} \, \mathrm{Watt\, m^{-2}\, T^{-1}}$| | |
| Turbulence trans. corr. length, |$L_\perp \sqrt{B}$| | |$1.5 \times 10^{5}\, \mathrm{m\, T^{1/2}}$| | |
| Coulomb logarithm, |$\Lambda _{\small {C}}$| | 20 | |
vsin i value taken from Glebocki & Gnacinski (2005) since the χ2 minimization did not produce a well-defined minimum. bProt value of 9.2 d used in final maps. cStassun et al. (2019).
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