Description
Chair of the session:
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Dr Anna Miotello15/10/2019, 11:30
Invited talk
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"Thanks to the advent of the Atacama Large Millimeter/submillimeter Array (ALMA), large surveys of protoplanetary disks in different star forming regions have been carried out to study the gas and dust components simultaneously. Carbon monoxide (CO) and its less abundant isotopologues have been observed to trace the bulk of the gas, while the dust was traced by the... -
Dr Leonardo Testi15/10/2019, 11:55
Contributed talk
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"The study of the properties of disks around young brown dwarfs can provide important clues on the formation of these very low-mass objects and on the possibility of forming planetary systems around them. We will report on the systematic ALMA search for cold dust around extinction limited samples of young brown dwarfs with infrared excess in the Lupus, Ophiuchus and... -
Dr Ilse Cleeves15/10/2019, 12:10
Invited talk
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"The chemistry of protoplanetary disks sets the initial composition of newly formed planets and may regulate the efficiency by which planets form. Disk chemical abundances typically evolve over timescales spanning thousands if not millions of years. Consequently, it was a surprise when ALMA observations taken over the course of a single year showed significantly... -
Dr Chunhua Qi15/10/2019, 12:25
Contributed talk
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"Protoplanetary disk radial and vertical thermal temperature gradients result in 2D snow surfaces, or condensation fronts. These are analogous to 1D snowlines, which are located where snow surfaces intersect with the disk midplane. CO and N2 are two of the most abundant disk molecules, and their snow surface locations could provide disk temperature structure... -
Dr Sean Andrews17/10/2019, 11:40
Invited talk
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The Disk Substructures at High Angular Resolution Project (DSHARP) observed 20 nearby protoplanetary disks in the 240 GHz continuum and 12CO J=2-1 spectral line with the Atacama Large Millimeter/submillimeter Array (ALMA) at a resolution of 35 milli-arcseconds (5 au). This talk will describe the motivation for this project and highlight the initial DSHARP results. We... -
Dr Dominique Segura-Cox17/10/2019, 12:05
Contributed talk
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Circumstellar disks are fundamental to the low-mass star and planet formation processes, yet their properties are only beginning to be unveiled in detail during the earliest Class 0 and I phases due to the dense gas and dust envelopes present at early times. ALMA observations of the older Class II protostar HL Tau exposed dark gaps and dust rings in the disk,... -
Dr Michiel Hogerheijde17/10/2019, 12:20
Contributed talk
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ALMA observations of planet forming disks over the past several years have firmly established that the grains responsible for the millimeter wavelength continuum emission have undergone a significant evolution in their radial and size distribution. Many disks show clear signs of both radial drift of grains and accumulation in rings. This grain evolution is... -
Dr Jeong-Eun Lee17/10/2019, 15:00
Invited talk
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Earth-like planets form mostly from dry refractory materials in the inner regions of protoplanetary disks; however, they might become habitable if water and organic molecules are delivered to their surfaces and atmospheres by planetesimals formed beyond the sublimation front of water. Complex organic molecules (COMs), which are the seeds of prebiotic material and... -
Dr François Ménard17/10/2019, 15:25
Contributed talk
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Planets form in Protoplanetary disks. New instruments like ALMA and VLT / SPHERE are revealing features in young disks that may be the traces of these planets: rings, gaps, spirals. The direct detection of forming planets still located inside their disk remains, however, very challenging. The consequence is that direct observational constraints on the formation... -
Dr Satoshi Ohashi17/10/2019, 15:40
Contributed talk
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HD 163296 is one of the best examples of the ring and gap structured protoplanetary disks. In addition, this disk is the only target where the ring and gap are spatially resolved in millimeter-wave polarization as well. By performing radiative transfer calculations of self-scattering polarization, we find that grain size and the dust scale height are the key... -
Dr Rachel Osten17/10/2019, 15:55
Contributed talk
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The unanticipated detection of mm flaring in Proxima Cen by ALMA has spurred follow-on observations to understand the origin and nature of stellar flaring and its impact in planetary systems. In April through June of 2019, a coordinated observing campaign took place to further these investigations
and learn more about the relationship between particle acceleration... -
Dr Izaskun Jimenez-Serra17/10/2019, 16:10
Contributed talk
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Hydrogen radio recombination lines (or RRLs) are excellent probes of the kinematics and physical conditions of the ionised gas in the ISM. The lines at sub-/millimeter wavelengths are particularly especial since they may present maser amplification. This is a rare effect that has been observed only toward a handful of objects. However, in the cases where maser RRLs... -
Dr John Tobin
Contributed talk
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"We have conducted a large survey of 328 protostars in the Orion star forming regions at ~40 AU (0.1"") resolution, using ALMA (0.87 mm) and the VLA (9 mm). This large sample was derived from Spitzer and Herschel surveys and constitutes the majority of the protostars in Orion, providing a statistical characterization of the protostellar disk and multiplicity...