Seminars and Colloquia at ESO Garching and on the campus

PLATO is the ESA's M3 mission optimized for the identification and characterization of Earth-like planets orbiting within the habitable zone of Sun-like stars, i.e., true Earth analogues. The mission development has already been completed and after finishing the late tests at ESTEC it should be shipped after the Summer to Kourou, for a launch planned for January 2027. 
In this talk I will summarize the performance of PLATO, the kind of data it will provide and the characteristics of the different data releases. A call for open time proposals during the first 2 years of operations was released last April 7th, and will remain open until May 21st. I will present how to prepare proposals for open time, the capabilities and limitations, and will provide some guidelines about the Proposal Handling tools at ESA.  

Spectroscopic surveys have been providing invaluable data in the field of Galactic archaeology and nucleosynthesis. While we are about to witness another revolution in the field with the start of 4MOST this year, we have already started to think about the next generations of spectroscopic survey facilities. In this talk, I will introduce the concept of the wide-field spectroscopic telescope (WST), which is planned for 2040s. I will discuss the need for equipping the WST with a higher spectral resolution spectrograph than the current generation of surveys, and how it can open new windows to study the origin of the elements and stellar populations in the Milky Way. 

When we have an unobscured view of the accretion disc, which peaks in the UV, QSOs display very blue UV–optical colours. However, there exists an important population of QSOs, obscured by dust, which are typically uncharacterised by optical spectroscopic surveys. These dusty QSOs could represent an important short-lived transitional phase in the evolution of galaxies (a “blow-out” phase).  Utilising data from DESI we can now, for the first time, explore a statistically significant sample of these reddened QSOs. Combining DESI spectra with radio data from the LoTSS DR2, we find a striking positive relationship between the amount of dust extinction and the radio detection fraction in DESI QSOs. This demonstrates an intrinsic connection between opacity and the production of radio emission in QSOs which may be due to outflow-driven shocks.  Exploring the radio morphologies and spectral slopes, we find that dusty QSOs typically have compact (small-scale) radio morphologies over 144 MHz, 1.4 GHz, and 3 GHz, which show an excess of steep-spectrum emission (α ≈ −1) not seen in normal blue QSOs or dusty QSOs with extended low-frequency radio emission. The strength of this excess steep-slope radio emission increases with increasing dust extinction, along with an overall increase in the radio-detection fraction. The majority of the dustiest QSOs with steep slopes have radio luminosities consistent with the prediction from a wind-shock model.  These results support a picture in which compact, dusty QSOs are undergoing a blow-out phase, where an AGN-driven wind and/or compact jet interacts with a dusty ISM, causing shocks, leading to steep spectral slopes and enhanced radio detection rates.

Since the revolutionary discovery of gravitational wave (GW) emission from a binary black hole merger in 2015, the remarkable GW detectors LIGO, Virgo and KAGRA have detected at least 220 compact object mergers. These events are transforming modern astronomy and physics. In particular, the first, and to date the only, binary neutron star merger, dubbed GW170817, was observed in both gravitational and electromagnetic radiation, thus opening up a new era in multi-messenger astrophysics. The multi-messenger characterisation of such an event has enabled major advances into diverse fields of modern physics from gravity, high-energy astrophysics, nuclear physics, to cosmology. In this talk, I will discuss our work in strong-field gravity astrophysics and how combining observations, theory and experiment have been key in making progress in this field. I will present the challenges and the opportunities that have emerged in multi-messenger astrophysics, particularly in the past decade, and what the future holds in this new era.