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Table 6

The χ2 tests for eleven model ingredients with respect to the Tycho-2 data.

The minimum χ2 test with
χ2 method scaling factors

Model Field Option (1) Option (2) χ 2 χ 2 χ 2 χ 2
ingredients (1)-T (2)-T (1)-T (2)-T

IMF 1 Kroupa (2008) Kroupa-Haywood v.6 140 42 39 14
SFR 1 constant decreasing (*) 171 42 31 14
thin disc age 1 9 Gyr 10 Gyr 51 42 16 14
1 12 Gyr 10 Gyr 40 42 14 14
age–metallicity relation 3 Twarog (1980) Haywood (2006) 11 4 6 2
age–velocity relation 3 Holmberg et al. (2009) Gómez et al. (1997) 11 4 4 2
thick disc 3 model TkD1 model TkD2 12 4 3 2

binarity 1 no yes 76 42 21 14
evolutionary tracks 1 package E1 package E2 50 42 18 14
atmosphere models 2 BaSeL 2.2 BaSeL 3.1 23 9 11 3
ISM 3 0.02 M pc-3 0.05 M pc-3 6 4 3 2

extinction model:
model A GPlane Drimmel & Spergel (2001) Marshall et al. (2006) 127 418 52 92
model B GPlane Drimmel & Spergel (2001) Marshall et al. (2006) 153 998 82 143
radial scale length GC model SL1 model SL2 29 49 17 18
GA model SL1 model SL2 49 27 20 15
GR model SL1 model SL2 22 22 20 19

Notes. In each case, the simulations were done towards one of the three reference regions: 1-Galactic plane, 2-intermediate latitudes and 3-Galactic pole or towards a special region. In the case of the extinction models, a bigger stripe within the Galaxy plane (GPlane) was chosen for analysis (| l | < 100 and | b | < 10). The radial scale length was tested towards the 3 cardinal directions: Galaxy centre (GC), anticentre (GA), and rotation (GR). The symbol (*) is a decreasing SFR from Aumer & Binney (2009).

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