The Galaxy as seen by RAVE L. Veltz, O. Bienaymé & A. Just.

The Galaxy as seen by RAVE

L. Veltz, O. Bienaymé & A. Just

Outline Model Observations Structure Kinematics Metallicity

Model Cigal

i => isothermal components

k => absolute magnitudes

Equation of stellar statistics:

Our modelOur model

Gravitation

alPotential

density distribution

velocitydispersion

€

Φ(z) = 2πG Σ0( z2 + D2 −D) + ρ eff z2

( )

Vertical gravitational potential:

self-consistentself-consistent

The analysis of the Galactic Disk structure relies on:

• Star counts

• Proper motions

• Radial velocities

2massComplete within

5 to 15.4 magnitudes

UCAC23 to 7 mas.y-1

within 6 to 14 magnitudes

RAVEInternal error of 2 km.s-1

Our samples Our samples

Fit the observations

Count Radial velocity

Proper motions

Kinematics distribution function

Thin disk Thic

k disk

Dwarf/Giant separation

Absolute magnitudes:

Sub-giants

MK=-0.89

MK=-0.17

Dwarfs MK=4.15

Clump giantsMK=-1.61

Color selectionColor selection

2mass-MSX-Hipparcos

HR diagram

Dwarf/Giant separation

Giants Dwarfs

Subgiants

Selection of dwarfs

Giants

Dwarfs

Subgiants

Dwarf/Giant separation

Dwarf/Giant separation

Giants Dwarfs

Subgiants

Dwarf/Giant separation

Giants Subgiants Dwarfs

hyp.: all stars are Dwarfs

Photometric distance

Observations versus Model

Thin/thick disk

transition

Thick disk

45 Km/s

Thin disk

15-20 Km/s

photometric distance (pc)

Scaleheight

Scale-height

Thin disk

Thick disk

Thin disk:

hz=225 ± 10 pc

Thick disk:

hz=1048 ± 36 pc

thick/

thin=8%

Scalelength

hR=2500pc

hR,1=1800pc & hR,2=2800pc

Kinematics

Selection of dwarfs

Selection of dwarfs

Selection of dwarfs

Selection of dwarfs

Dispersion-color

Dispersion-color

B-V <=> J-K

Dispersion-color

Dispersion - color

Dispersion vs distance

sigW-col (distance)

Metallicity

SDSS - RAVE

Metallicity

Metallicity-dispersion

Conclusions

Results

Kinematical decomposition Clear separation between the thin

and the the thick disk Separation of dwarfs/giants Determination Scale height /length Kinematics function of Z Metallicity

Space kinematics