Calendar
40 studenti
primo turno 9.30
secondo turno 11
Stanza Google meet: meet.google.com/sxz-cctp-tsc
Speaker: Giuliana Cosentino (Space, Earth and Environment Department, Chalmers University of Technology, SE)
Title: Feedback from Supernova Remnants: triggering Star Formation in the ISM
Abstract: Supernova remnants (SNRs) drive large-scale shocks that locally enhance the density of the surrounding material but also inject vast amounts of energy and momentum that largely perturb and disperse the Interstellar Medium (ISM).
The interplay between these two effects is considered paramount in regulating the star formation efficiency in galaxies. However, how SNRs affect the physical conditions of the ISM is not well constrained from an observational point of view.
In this talk, I will present our work aimed to address this question.
I will show our study of the large scale shock triggered by the SNR W44 on the molecular cloud G034. I will show how the shock, probed by Silicon Monoxide (SiO) and observed with ALMA, enhances the density of the processed gas to values compatible with those required for massive star formation and has helped to shape the cloud. I will also present our exploratory large single-dish
observing program SHREC, aimed to observe the molecular shock tracer
SiO(2-1) toward a sample of 30 SNRs known to be interacting with molecular clouds. I will introduce the aim and technical aspects of SHREC and present the first results obtained toward the SNRs IC443.
IC443 is a well known SNR, expanding into and interacting with a nearby toroidal molecular cloud. Toward the major site of interaction, known as clump G, we estimate the mass of the shocked gas to be 100 Msun.
The shock driven by IC443 into this material enhances its density by a factor >10, to value consistent with those required to ignite star formation. Finally, we estimate that between 35-50% of the momentum injected by IC443 is transferred to the nearby molecular material. Our work therefore indicates that the molecular ISM is an important carrier of the SNR momentum and that the SNR-molecular cloud interaction play a crucial role in the regulating star formation in galaxies.
Stanza Google Meet: https://meet.google.com/sxz-cctp-tsc
Speaker: Marcell Tessenyi (BSS Italia)
Titolo: Mauve and Twinkle: UV and infrared satellites delivered through a new model
Abstract:
Mauve and Twinkle are part of a new family of satellites from Blue Skies Space that use the latest commercial space industry developments to deliver scientific missions on vastly accelerated timescales, setting a new pace for science discovery.
Mauve is a low-Earth orbit (LEO) small satellite containing a UV spectrometer and a 15cm class telescope. It is designed to monitor the activity of nearby stars, with a particular focus on M-dwarfs that might host habitable zone planets. The construction begins this year with partners C3S and ISISpace, for a planned launch in early 2024. Twinkle is a larger LEO satellite carrying a 0.45m telescope and an infrared spectrometer with a simultaneous wavelength coverage from 0.5 to 4.5μm. It is designed to detect the composition of atmospheres of exoplanets orbiting bright stars, as well as solar system objects such as comets and asteroids. The satellite, expected to launch in late 2024, is based on a high-heritage platform from Airbus and an instrument by ABB Canada. Both satellites will provide scientific data highly complementary to existing and upcoming exoplanet related space and ground-based observatories, including NASA/ESA/CSA’s James Webb Space Telescope and ESO’s Extremely Large Telescope.
Blue Skies Space is able to deliver Mauve and Twinkle thanks to the substantial transformations currently on-going in the space sector in Europe and beyond. Blue Skies Space Italia S.R.L. was set up this year to leverage the capabilities and expertise of the Italian science and technology community and help coordinate European science, technology and funding activities.
Stanza Google Meet: https://meet.google.com/sxz-cctp-tsc
Speaker: Ciro Pinto (INAF / IASF-Palermo)
Titolo: “Fast growth and feedback of black holes accreting beyond the Eddington limit”
Abstract:
The detection of fully-grown supermassive black holes in active galactic nuclei at high redshift, when the Universe was young, challenges the theories of black holes growth, requiring long periods of high accretion, most likely above the Eddington limit. These objects will be difficult to study in detail, even with future advanced observatories. In the nearby Universe there are compact objects with a similar accretion regime that can be used as proxy for primordial black holes. Ultraluminous X-ray sources (ULXs) are mainly nearby stellar-mass black holes and neutron stars accreting above their Eddington limit. This was understood after the discovery of coherent pulsations and cyclotron lines in some ULXs, indicating that at least a fraction of them hosts neutron stars as compact objects and, finally, our discovery of powerful winds as predicted by theoretical models of super-Eddington accretion. ULX winds carry a huge amount of power owing to their mildly relativistic speeds (~0.2c) and are able to significantly affect the surrounding medium, producing the observed 100s pc super bubbles, and limit the amount of matter that can reach the central accretor. The study of ULX winds is therefore quintessential to understand 1) how much and how fast can matter be accreted by black holes and 2) how strong is their feedback onto the surrounding medium in the regime of high accretion rate such as for quasars and supermassive black holes at their peak of growth. I will provide an overview on this phenomenology and discuss how we can use similar techniques onto highly-accreting supermassive black holes to understand their fast growth and feedback onto the host galaxy.
Google meet: https://meet.google.com/sxz-cctp-tsc
Speaker: Angelo Adamo (INAF)
Titolo: Domicili cosmici – Lontani pianeti ai confini dello sguardo
Abstract: Si fa presto a dire “pianeta”, un termine che sembra non richiedere mai precisazioni, tanto appare ovvio; banale, quasi. Eppure richiama alla mente un’immagine il cui significato (fra diaspore spaziali, fughe e traslochi dal sapore fantascientifico capaci di modificare il senso e il valore di un concetto tanto semplice e comune quanto vago) è cambiato più e più volte nel corso della storia, dalle origini ai giorni nostri. In “Domicili cosmici” l’astrofisico, divulgatore, fumettista e musicista Angelo Adamo raccoglie e organizza una grande quantità di idee mutuate non solo dalla geologia, dall’astronomia e dalla sua storia, ma anche dalla letteratura, dalla poesia e dal cinema, per ripercorrere le tappe di questa continua trasformazione. E lo fa arricchendo il testo con le sue tavole originali e suggestive, veri e propri calembour disegnati, che si intrecciano con i giochi di parole e le espressioni matematiche disseminate nel testo. Il risultato è quasi un’antologia, un compendio illustrato di filosofia astronomica che racconta un’evoluzione culturale fatta di idee, ipotesi, suggestioni, storie, esperimenti, simulazioni. E speranze.
Speaker: Fabio Favata (ESA)
Titolo: Agenzie spaziali e telescopi spaziali: un passato di grande successo, un futuro incerto
Abstract: Il primo telescopio spaziale è stato lanciato nel 1968, e per i ricercatori del XXI secolo l’esistenza di una flotta di telescopi in orbita, accessibile a qualsiasi ricercatore qualificato, è data per acquisita. È anche spesso dato per scontato che ciascuna generazione di telescopi spaziali sia seguita da una generazione di telescopi più potenti. Le agenzie spaziali nazionali (come la NASA negli USA, o l’ASI in Italia) e quelle internazionali (come l’ESA in Europa) sono spesso percepite come lo strumento istituzionale al servizio della comunità scientifica, a cui è affidato il ruolo di tradurre in realtà i progetti scientifici dei ricercatori. Questa percezione è stata abbastanza fedele alla realtà nei 50 anni trascorsi dal lancio del primo telescopio spaziale.
Nel frattempo però l’ecosistema spaziale mondiale è cambiato enormemente, così come sono cambiate le dinamiche e la governance delle agenzie spaziali, e oggi è tutt’altro che evidente che l’approccio che ha portato a enormi successi nei 50 passati possa continuare a funzionare in futuro. In parole povere, non è affatto scontato che il modello che ha portato a questi successi sia adeguato ad affrontare le sfide odierne.
Chi lavora nelle agenzie spesso nota che la comunità scientifica non è necessariamente al corrente di come un’agenzia funziona, di quali sono le dinamiche attraverso cui vengono prese le decisioni chiave che determinano il futuro della scienza spaziale. Di conseguenza spesso non è chiaro ai ricercatori come agire in maniera efficace per far sì che la scienza dallo spazio continui in futuro ad avere successo.
Il seminario intende fornire una visione di come funziona un’Agenzia Spaziale (in particolare l’ESA) e di quali sono le sfide epocali a cui va incontro oggi la scienza spaziale.
Stanza Google Meet: https://meet.google.com/sxz-cctp-tsc
Speaker: Darius Modirrousta-Galian (Yale University)
Title: The three regimes of atmospheric evaporation for super-Earths and sub-Neptunes
Abstract:
A significant fraction of super-Earths and sub-Neptunes are thought to experience an extreme loss of volatiles because of atmospheric evaporation in the early stages of their life. Though the mechanisms behind the extreme mass loss are not fully understood, two contenders have been widely discussed: photoevaporation from X-ray and ultraviolet irradiation and core powered mass loss. In this talk, I will discuss the new model of Modirrousta-Galian & Korenaga, suggesting that both mechanisms occur but with different timescales and that atmospheric evaporation can be classified under three regimes. This talk will summarize by explaining why the next step in exoplanetary science is to incorporate more realistic formational and geophysical modeling, and how such models could be tested through observations.
60 pax