DOES THE STELLAR DISTRIBUTION FLARE? A COMPARISON OF STELLAR SCALE HEIGHTS WITH LAB H i DATA

The question of whether the stellar populations in the Milky Way take part in the flaring of scale heights as observed for the H i gas is a matter of debate. Standard mass models for the Milky Way assume a constant scale height for each of the different stellar distributions. However, there is mounting evidence that at least some of the stellar distributions reach, at large galactocentric distances, high altitudes, which are incompatible with a constant scale height. We discuss recent observational evidence for stellar flaring and compare it with H i data from the Leiden/Argentine/Bonn survey. Within the systemic and statistical uncertainties we find a good agreement between both.

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