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 Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

Although mid-to-late type M dwarfs are the most common stars in our stellarneighborhood, our knowledge of these objects is still limited. Open questionsinclude the evolution of their angular momentum, internal structures, dustsettling in their atmospheres, age dispersion within populations. In addition,at young ages, late-type Ms have masses below the hydrogen burning limit andtherefore are key objects in the debate on the brown dwarf mechanism offormation. In this work we determine and study in detail the physicalparameters of two samples of young, late M-type sources belonging to either theChamaeleon I Dark Cloud or the TW Hydrae Association and compare them with theresults obtained in the literature for other young clusters and also for older,field, dwarfs. We used multi-wavelength photometry to construct and analyzeSEDs to determine general properties of the photosphere and disk presence. Wealso used low resolution optical and near-infrared spectroscopy to studyactivity, accretion, gravity and effective temperature sensitive indicators. Wepropose a VO-based spectral index that is both temperature and age sensitive.We derived physical parameters using independent techniques confirming thealready common feature/problem of the age/luminosity spread. In particular, wehighlight two brown dwarfs showing very similar temperatures but clearlydifferent surface gravity (explained invoking extreme early accretion). We alsoshow how, despite large improvement in the dust treatment in theoreticalmodels, there is still room for further progress in the simultaneousreproduction of the optical and near-infrared features of these cold youngobjects.

Physical parameters of late M-type members of Chamaleon I and TW Hydrae Association: Dust settling, age dispersion and activity