Maria Morales

LAEFF

I am a PhD. student funded by the Instituto Nacional de Técnica
Aeroespacial (INTA). My Thesis advisor is David Barrado y Navascués
and I am working at LAEFF.  My Thesis is focused on the formation
and properties of very low mass stars, brown dwarfs and isolated
planetary mass objects.

On the one hand we have selected a number of young associations
(3-5 Myr) belonging to the Lambda Orionis Star Forming Region
(SFR). Our goal is to perform a comprehensive study trying to solve
some key questions such as: which is the lower cut-off for the
formation of brown dwarfs and isolated planetary mass objects,
which is the role of the environment, and which mechanisms are
involved. We are making use of optical and near-IR ground based
imaging and spectra together with Spitzer and XMM-Newton data to
produce accurate IMFs of the different associations, determine the
ratio of Classical TTauri stars and substellar analogs to Weak-line
TTauri stars and its evolution with time, and derive accretion
rates and X-ray activity during the initial few million years,
within the substellar domain.

On the other hand we are also conducting variability studies to
investigate the physics of brown dwarf atmospheres both in young
associations and in the field. We use optical, near- and mid-IR
photometry to derive very accurate light curves in order to: i)
determine the cause of variability (magnetically induced spots,
accretion from surrounding envelopes, clouds, eclipses due to
unseen companions or disks...), ii) obtain rotational periods
through the light curve modulation due to superficial
inhomogeneities, iii) search for flares on these fully convective
objects, and iv) investigate the variability amplitude associated
to atmospheric changes in late-L objects.