Objective 1: Analysis and Modelling of Data
- Task 1.1.1: Reduction and Analysis of ALMA Data for Ringed-Disks
The data modeling part of this task is complete, and analysis is ongoing. The main result of this task is the confirmation that millimeter-sized grains in ringed disks are concentrated in a flat midplane layer. This finding supports earlier suggestions made through our analysis of HL Tau data in 2018, marking an early success for the Dust2Planets project.
Task 1.1.2: Reduction and Combined Analysis of ALMA, HST, and JWST Data for Edge-On Disks
This task involves the analysis of data from the James Webb Space Telescope (JWST), ALMA, and the Hubble Space Telescope (HST). The PI was awarded two JWST programs in Cycles 1 and 2. Data from Cycle 1, covering four targets, have been analyzed and published, with the results appearing in four papers. Analysis of Cycle 2 data (covering 11 targets) is ongoing.
In addition, the edge-on disk PDS 453 was recently modeled as well, using data from HST, SPHERE, and spectroscopic observations to quantify water ice content in the disk.
Task 1.2: Hydrodynamical Models and Predictions
This task has just begun. Although this represents a slight delay, the results are expected well before the end of the project, with no anticipated impact on the overall scientific output. This task focuses on creating hydrodynamic models to predict the evolution (growth, destruction,dynamics) of dust in protoplanetary disks, an important step for understanding disk dynamics and early planet formation.
Objective 2: Analog Fabrication and Diffusion Measurements
Task 2.1: Fabrication of Analogues and Microwave Measurements
Fabrication and measurent of several 3D-printed analogs of dust particles using microwave measurements is underway. In 2024, the anechoic chamber was completely refurbished. This improvement, which was not initially planned, has significantly enhanced the performance of the instrumental set-up. Measurements have just resumed , at the time of writing. While the set-up was being upgraded, several analogs of different shapes were fabricated (ice coated fractals, random gaussian spheres, ...). As part of the collaboration, new materials for 3D printing were also developed that are better matched to the expected refractive indices of astronomical dust material (silicates, carbonaceous coumpounds).
Task 2.2: Scattering Phase Function and Polarization for Young Disks
A new extraction software was developed from scratch to extract scattering phase functions in total intensity and linear polarization from astronomical disk images. The software, which is now available publicly on GitHub, allows for the fast and efficient analysis of scattering properties, with the addition of proper error handling and a user-friendly interface. We will now focus on analyzing the scattering phase functions from more than 25 individual disks using data from the SPHERE science archive, with a focus on young disks.
Most Significant Achievements
JWST Time Allocation and Papers
Securing JWST time as a principal investigator was a significant achievement in itself. The four scientific papers published from the data of JWST Cycle 1 represent substantial advances in understanding vertical dust settling in protoplanetary disks.
Development of Scattering Phase Function Extraction Software
The creation of a software tool by Maxime Roumesy to extract scattering phase functions from raw images is a key achievement. This tool allows for quick, accurate analysis and is now available for use by the wider scientific community.
Multi-Wavelength Approach to Disk Studies
The project has focused on multi-wavelength studies of dust in disks, covering optical, infrared, and thermal emissions. This combination of different data types has already provided insights into disk structure. However, the analysis of gas content, especially in edge-on disks, promises to enhance this understanding. The project has prepared a large ALMA program to study molecular gas lines in nine edge-on disks, with data already secured for the first phase.
ALMA Large Program Selection
A major achievement is the recent allocation of an ALMA large program that we lead. The proposal was ranked first among all submitted proposals in Cycle 11. This program will allow for the measurement of molecular gas lines in nine edge-on disks, providing critical data for understanding disk temperature and density stratifications. This initiative is expected to significantly enhance the overall understanding of vertical settling in disks.
