English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

The colour and metallicity gradients observed in spiral galaxies suggest thatthe mass-to-light ratio (M*/L) of the stellar disc is a function of radius.This is indeed predicted by chemo-photometric models of galactic discs.  We investigate the distribution of luminous and dark matter in spiralgalaxies, taking into account the radial dependence of the stellar M*/L - whichis usually assumed to be constant in studies of the mass structure.  From the chemo-photometric models of Portinari et al. (2004) and in agreementwith the observed radial profiles of galaxy colours, we derive the typicalaverage M*/L profile of the stellar discs of spiral galaxies. We compute thecorresponding Variable Mass-to-Light (VML) stellar surface density profile andthen the VML disc contribution to the circular velocity. We use the latter,combined with a well studied dark matter velocity profile, to mass model theco-added rotation curves of Persic et al. (1996). (Seehttp://www.facebook.com/home.php#!/group.php?gid=310260450630 to retrieve extrainformation on the kinematics of galaxies) By investigating rotation curves inthe framework of VML stellar discs, we confirm, to a first approximation, thescenario obtained with the constant M*/L assumption: a dark matter halo with ashallow core, an inner baryon-dominated region and a larger proportion of DarkMatter in smaller objects. However, the resulting size of the the dark halocore and of the inner baryon dominance region are somewhat smaller. Thestronger role that VML discs have in the innermost regions is important toconstrain the galaxy mass structure in both Lambda Cold Dark Matter and MONDscenarios.

The structure of spiral galaxies: radial profiles in stellar Mass-to-Light ratio and the Dark Matter distribution