Gravitational stability in the disk of M51

TL;DR

This paper investigates the gravitational stability of the gas in the galaxy M51 by combining multi-wavelength data to analyze the Toomre Q parameter, aiming to understand star formation laws.

Contribution

It presents a detailed analysis of the gravitational stability in M51 using combined molecular, atomic, and stellar data, providing insights into star formation physics.

Findings

Derived gas and stellar density maps for M51.

Analyzed gravitational stability using the Toomre Q parameter.

Enhanced understanding of star formation regulation in spiral galaxies.

Abstract

Star formation laws, like i.e. the Schmidt law relating star formation rate and total gas density, have been studied in several spiral galaxies but the underlying physics are not yet well understood. M51, as a nearby face-on, grand design spiral galaxy studied in many line transitions, is an ideal target to study the connection between physical conditions of the gas and star formation activity. In this contribution we combine molecular, atomic, total gas and stellar surface densities and study the gravitational stability of the gas (Schuster et al.2007, Hitschfeld et al. in prep.). From our IRAM-30m 12 CO2-1 map and complementary HI-, Radio Continuum- and ACS-HST B-band-data we derive maps of the total gas density and the stellar surface density to study the gravitational stability of the gas via the Toomre Q parameter.