... resolved

Table 2 is only available in electronic form at http://www.edpsciences.org

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... Engels

www.hs.uni-hamburg.de/DE/Ins/Per/Engels/engels/wcatalog.html

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... respectively

The following parameters also enter the model: a distance Sun-Galactic Centre of 8.5 kpc (Kerr & Lynden-Bell 1986), Oort's constants of A = 14.4 km s^-1 kpc^-1, B = -12.0 km s^-1 kpc^-1, and higher order terms $\frac{{\rm d}^2\theta}{{\rm d}r^2}_{\vert R_0}$ = -3.4 km s^-1 kpc^-2, $\frac{{\rm d}^3\theta}{{\rm d}r^3}_{\vert R_0}$ = 2.0 km s^-1 kpc^-3(Pont et al.1994), and a Solar motion of 19.5 km s^-1in the direction l = 56 $.\!\!^\circ$0, b = 23 $.\!\!^\circ$0 (Feast & Whitelock 1997).

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