Lorenzon Giuliano (National Center for Nuclear Research, Warsaw)
The idea of a strict relationship between the evolution of the cold gas and dust components in the interstellar medium (ISM) of quiescent galaxies (QGs) has recently been challenged thanks to the combined use of the Near/Mid-infrared JWST and the sub-mm ALMA telescopes. Such galaxies have little to no star formation and are typically considered poor in ISM, but new evidence is building up revealing both gas-rich and dust-rich QGs, especially at z>1. Such a discovery is changing the way we interpret QGs, raising new questions about the way we select them and on the physics regulating their formation. We use the state-of-the-art suit of cosmological simulations SIMBA to tackle the physical processes generating dust-rich QGs up to z~2 by comparing the effect of internal and environmental quenching mechanisms on the evolution of the ISM content. While dust is generally associated with mechanisms of star formation and has a generally short lifespan, we find in SIMBA indications that grains can survive for much longer due to prolonged accretion of metals from the ISM. This mechanism naturally competes with grain destruction, which is mainly driven by the energy injection of the active galactic nucleus (AGN), suggesting that the interplay between the AGN and the dust growth timescales may be the reason for the observed variety in the dust content of QGs. The results from this theoretical analysis are soon to be directly tested thanks to ad-hoc observations with the ALMA sub-mm telescope we managed to obtain during the Cycle 11 observation campaign.
CAMK Annual Conference
Ricardo Salinas (CAMK/Araucaria, Warsaw)
While adaptive optics is the most widespread method to compensate for atmospheric turbulence, these methods are particularly difficult to implement in the optical regime given the technical challenges imposed by the short coherence times. An alternative to reach the diffraction limit of an optical telescope is provided by speckle interferometry, where, instead of real-time corrections, observations are obtained in timescales similar to the coherence time (a few ms), and the diffraction limit is recovered via a post-hoc reduction in Fourier space. In 2019, the Gemini telescopes commissioned two speckle interferometers, Zorro and 'Alopeke, owned by NASA Ames, which have remained as "permanent visiting" instruments since then. In this talk I will present the characteristics of these instruments, to then present a number of science cases where these instruments are particularly suited, mostly leaning to my own research on RR Lyrae in binary systems, and blue stragglers in hierarchical triplets.
