Overview of research activities: from disks to planets
These are the projects that I am working on now / will be working on shortly in the future:
Gaps in disks around Herbig Ae/Be stars
Gaps in proto-planetary disks are exciting since they may a proxy for forming planets. Disks around Herbig Ae/Be stars are especially interesting because they belong to the largest and brightest disks we know of. Finding such structures is challenging and Spectral Energy Distribution (SED) studies do not provide unequivocal evidence for gaps, especially in disks around higher mass Herbig AeBe stars. Recently it has been shown that many of these Herbig stars classified as flaring are in fact disks with developing or fully cleared large gaps.
Together with Koen Maaskant I am leading high priority ALMA cycles 2, 3 and 4 programs to confirm and the presence of gaps in 3 Herbig Ae/Be disks and to investigate the disk structure in high spatial resolution (proposal codes 2013.1.00658.S, 2015.1.00192.S and 2016.1.00826.S ).
Recently I have published the first paper on these data in a paper called “A cavity and further radial substructures in the disk around HD 97048” [summary, ADS].
Circumstellar disks around Brown Dwarfs
I lead the ALMA cycle 1 and 3 programs “Detection and characterization of protoplanetary disks across the stellar/substellar transition” (Project code 2012.1.00743.S) and “Dynamical Masses of a Taurus Low Mass Star and Brown Dwarf ” (Project code 2015.1.01460.S) in close collaboration with Francois Menard, Jenny Patience, Paul Harvey, Simon Casassus, Joanna Bulger and Christophe Pinte.
The main goal of our program is to measure the mass of these disks. More in general, measuring the disk mass is necessary to understand (1) whether there is enough material to form planets or not around these objects, (2) how the disk mass scales with central object mass, and (3) how the properties of the disks evolve over time.
The first paper showcasing our results for the BD disks in the Upper Sco star forming region was published as “Dust Masses of Disks around 8 Brown Dwarfs and Very Low-mass Stars in Upper Sco OB1 and Ophiuchus” [ADS]. Read a complete description of the project ‘Disks around brown dwarfs with ALMA’.
Warm CO gas in the disks around Herbig Ae/Be stars
Ro-vibrational CO emission traces the inner ~50 au (Astronomical Units. 1 au equals the distance between earth and the sun) of the disks around Herbig Ae/Be stars. We use the CO emission to study the structure of disks around a sample of 13 Herbig Ae/BE stars, and to investigate the connections between disk structure and gas excitation conditions. My most recent publication on this topic dates back to 2015: “The structure of disks around Herbig Ae/Be stars as traced by CO ro-vibrational emission” [ADS].