Query : 2006A&A...459..703J

2006A&A...459..703J - Astronomy and Astrophysics, volume 459, 703-716 (2006/12-1)

An evolutionary disc model of the edge-on galaxy NGC 5907.


Abstract (from CDS):

We present an evolutionary disc model of the edge-on galaxy NGC 5907 based on a continuous star formation history and a continuous dynamical heating of the stellar subpopulations. This model explains the disparate two observational facts: 1) the exponential vertical disc structure in the optical and NIR of the non-obscured part of the stellar disc and 2) the FIR/submm luminosity enhanced by about a factor of four near the obscured mid-plane, which requires additional dust and also stellar light to heat the dust component. We use multi-band photometry in U, B, V, R, and I-band combined with radiative transfer through a dust component to simultaneously fit the vertical surface-brightness and colour index profiles in all bands adopting a reasonable star formation history and dynamical heating function. The vertical distribution of the stellar subpopulations are calculated self-consistently in dynamical equilibrium and the intrinsic stellar emissivity is calculated by stellar population synthesis. The final disc model reproduces the surface-brightness profiles in all bands with a moderately declining star formation rate and a slowly starting heating function for young stars. The total dust mass is 5.7x107M as required from the FIR/submm measurements. Without a recent star burst we find in the midplane an excess of 5.2-, 4.0-, and 3.0-times more stellar light in the U-, B-, and V-band, respectively. The corresponding stellar mass-to-light ratios are 0.91 in V- and 1.0 in R-band. The central face-on optical depth in V-band is τVf^_=0.81 and the radial scale length of the dust is 40% larger than that of the stellar disc. Evolutionary disc models are a powerful method to understand the vertical structure of edge-on galaxies. Insights into the star formation history and the dynamical evolution of stellar discs can be gained. FIR/submm observations are necessary to restrict the parameter space for the models.

Abstract Copyright:

Journal keyword(s): stellar dynamics - galaxies: kinematics and dynamics - galaxies: evolution - galaxies: stellar content - galaxies: structure

Simbad objects: 4

goto Full paper

goto View the references in ADS

Number of rows : 4
N Identifier Otype ICRS (J2000)
ICRS (J2000)
Mag U Mag B Mag V Mag R Mag I Sp type #ref
1850 - 2023
1 NGC 891 H2G 02 22 32.907 +42 20 53.95 11.08 10.81 9.93 7.86   ~ 1607 2
2 IC 2531 EmG 09 59 55.6140265128 -29 37 04.575809208   13.19   11.54 12.1 ~ 136 1
3 NGC 5906 GiG 15 15 53.687 +56 19 43.86   11.4       ~ 732 1
4 M 92 GlC 17 17 07.39 +43 08 09.4     6.52     ~ 2016 0

To bookmark this query, right click on this link: simbad:objects in 2006A&A...459..703J and select 'bookmark this link' or equivalent in the popup menu


© Université de Strasbourg/CNRS

    • Contact