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Investigating the link between protoplanets, disk substructures and disk winds

Sede A. Riccò Via Santa Sofia 78, Catania

Protoplanetary disks are now routinely observed around young stars but the planets they produce remain elusive to detect. So far, we have only one confirmed direct detection of protoplanets in the disk of PDS 70, with some tentative results (e.g. AB Aur). Yet disk structures are found almost ubiquitously across the sample of resolved disks. We are investigating the potential relationship between inner disk winds and outflows (traced by optical emission lines, such as ), and the presence and type of disk substructures. We aim to determine whether or not the various substructures are the direct results of protoplanet formation.
I will present new results from recent and archival observations of PDS 70. In order to investigate such connections between winds, substructures and planets, we turn to the one system where we have certainly detected the planets. We have carefully applied established techniques to the high-resolution spectra to reveal previously unseen forbidden emission profiles. These results suggest a significant wind originating from the inner disk. We compare these results and measurements of the mass accretion rate and disk properties to those of other weakly accreting young stars and those with transition disks.
We are also carrying out this investigation for the PENELLOPE/ULLYSES sample of ~80 young stars. This complements existing surveys of such winds/outflows, whilst allowing for further exploration of the relation to disk substructures, towards a more complete statistical survey.

Elucidating diffuse Galactic synchrotron emission for precision 21cm and CMB cosmology

Sede A. Riccò Via Santa Sofia 78, Catania

The next generation of Cosmic Microwave Background experiments are poised to probe the inflationary period of the Universe through the measurement of primordial B-modes, whilst 21cm experiments are observing the reionization history of the early Universe and formation of Large-Scale Structure through the mapping of neutral hydrogen. These two complementary fields span the radio to microwave frequency regimes and share a pivotal data reduction task: foreground component separation.

Diffuse Galactic synchrotron emission is the dominant foreground for arcmin/degree scale cosmological surveys operating across MHz frequencies in intensity, and at all frequencies under 60 GHz in polarised intensity. In this talk I will present measurements of the synchrotron spectral index and curvature between 73 MHz and 1 GHz through the combined use of pilot MeerKLASS, Haslam, Maipu/MU and LWA data. I will discuss the advances that can be made to component separation algorithms thanks to more sophisticated foreground emission modelling and will present a spatially complex, all-sky model of the synchrotron spectral index formed using convolutional neural networks trained on sets of both high- and low-resolution empirical data. Such advances will, and already are, expanding our understanding of the spatial and spectral form of this complex emission; ameliorating component separation for both CMB and 21cm intensity mapping experiments.