Feedback da AGN e cinematica del gas ionizzato nella galassia a z~2 GMASS 0953

In questo lavoro abbiamo analizzato due spettri nel vicino infrarosso (rest-frame visibile) di GMASS 0953, un galassia star-forming di grande massa a z~2 che ospita un nucleo galattico attivo (AGN). La nostra analisi di due set di dati realizzati dagli spettrografi GNIRS e SINFONI ha rivelato un outflow di gas ionizzato visibile dalle transizioni di [OIII]λλ4959,5007 del quale abbiamo studiato le proprietà (es. massa, tasso di espulsione) per stabilire l’impatto che l’espulsione di materiale può avere sulla galassia. Diverse osservazioni hanno infatti rivelato espulsioni di gas dalle regioni nucleari delle galassie provocate dai venti e/o dalla pressione di radiazione sprigionati dagli AGN, che possono ridurre il combustibile necessario per la nascita delle stelle, favorendo l'evoluzione passiva dei sistemi in cui gli outflow sono in atto. Tuttavia, a causa della nostra ignoranza sulla distribuzione della polvere nella galassia e sulla geometria dell’outflow, la nostre misure non ci hanno permesso di pronunciarci in maniera definitiva sull’impatto che l’espulsione di gas può avere sull’attività di formazione stellare di GMASS 0953. Parallelamente, grazie alla disponibilità di dati di spettroscopia a campo integrale (Integral Field Spectroscopy, IFS) realizzati dallo spettrografo SINFONI, abbiamo studiato la cinematica del gas ionizzato della galassia. La nostra analisi, condotta tramite un algoritmo 3D che minimizza gli effetti dovuti alla bassa risoluzione spaziale di cui possono essere affette le osservazioni IFS, ha evidenziato la presenza di un disco per il quale abbiamo derivato la curva di rotazione, che ci ha consentito di quantificare la massa dinamica di GMASS 0953. Lo studio della cinematica ha messo in risalto i limiti legati alle osservazioni spettroscopiche a campo integrale dotate di bassa risoluzione spaziale, che rende incerta la derivazione della dispersione di velocità del gas e dunque la misura del rapporto (V/σ) di una galassia

From fueling to quenching star formation across cosmic time

Investigating the mechanisms that regulate star formation (SF) across cosmic time is a complex issue. Most of our knowledge of the cosmic SF history at z > 3 relies on UV surveys, which could miss SF obscured by dust. IR/mm-selections of galaxies are thus a crucial tool for unveiling the total amount of SF. In addition, active galactic nuclei (AGN) are considered to play a crucial role in galaxy evolution. According to models, AGN could be decisive in suppressing SF in massive galaxies. Despite this, some theories predict that AGN could also trigger SF inside outflows. These two mechanisms have been named as “negative” and “positive” AGN feedback and their study is crucial to understand what regulates SF inside galaxies. The aim of this thesis is to investigate the processes that fuel and suppress SF across cosmic time. On one side, we focused on the study of cold gas in the early Universe. We derived the first [C II] luminosity function at z~5 from a mm-selection of galaxies. By using [C II] as a SF rate indicator, we measured the cosmic SF rate density at z~5, which shows a possible excess compared to previous estimates. On the other side, we studied the impact of negative and positive AGN feedback on SF. First, we investigated negative feedback in a massive galaxy at z~2, which will possibly evolve into a passive galaxy. Then, we studied positive feedback in a sample of 70 nearby star-forming galaxies by using UV spectroscopy. We detected in several objects blueshifted stellar absorption, which could be indicative of young stars formed inside outflows. Despite the uncertainties affecting our analysis, studying cold gas and AGN feedback represents a powerful approach to constrain the processes that feed and quench SF across cosmic time

A multiwavelength study of a massive, active galaxy at z similar to 2:coupling the kinematics of the ionized and molecular gas

We report a multiwavelength study of the massive ( M-* greater than or similar to 10(11)M(circle dot)), z similar to 2 star-forming galaxy GMASS 0953, which hosts an obscured AGN. We combined near-infrared observations of the GNIRS, SINFONI and KMOS spectrographs to study the kinematics of the [O III] lambda 5007 and H alpha emission lines. Our analysis shows that GMASS 0953 may host an ionized disc extending up to 13 kpc, which rotates at a velocity of V-ion = 203(-20)(+17) km s(-1) at the outermost radius. Evidence of rotation on a smaller scale (R similar to 1 kpc) arises from the CO(J = 6-5) line. The central velocity V-CO = 320(-53)(+92) km s(-1) traced by the molecular gas is higher than V-ion, suggesting that the galaxy harbours a multiphase disc with a rotation curve that peaks in the very central regions. The galaxy appears well located on the z = 0 baryonic Tully-Fisher relation. We also discuss the possibility that the [O III] lambda 5007 and H alpha velocity gradients are due to a galactic-scale wind. Besides, we found evidence of an AGN-driven outflow traced by a broad blueshifted wing affecting the [O III] lambda 5007 line, which presents a velocity offset Delta v = -535 +/- 152 km s(-1) from the systemic velocity. Because of the short depletion time-scale (tau(dep) similar to 10(8) yr) due to gas ejection and gas consumption by star formation activity, GMASS 0953 may likely evolve into a passive galaxy. However, the role of the AGN in depleting the gas reservoir of the galaxy is quite unclear because of the uncertainties affecting the outflow rate

Trends of Phase I Clinical Trials in the Latest Ten Years across Five European Countries

Phase 1 clinical trials represent a critical phase of drug development because new candidate therapeutic agents are tested for the first time on humans. Therefore, international guidelines and local laws have been released to mitigate and control possible risks for human health in agreement with the declaration of Helsinki and the international Good Clinical Practice principles. Despite numerous scientific works characterizing the registered clinical trials on ClinicalTrials.gov, the main features and trends of registered phase 1 clinical trials in Europe have not been investigated. This study is aimed at assessing the features and the temporal trend of distribution of phase 1 clinical studies, carried out in the five largest European countries over a ten-year period (2012-2021), and to evaluate the impact of the Italian regulatory framework on the activation of such studies

A SPectroscopic Survey of Biased Halos in the Reionization Era (ASPIRE): A First Look at the Rest-frame Optical Spectra of z > 6.5 Quasars Using JWST

© 2023. The Author(s). Published by the American Astronomical Society. This is an open access article distributed under the Creative Commons Attribution License, to view a copy of the license, see: https://creativecommons.org/licenses/by/4.0/Studies of rest-frame optical emission in quasars at z > 6 have historically been limited by the wavelengths accessible by ground-based telescopes. The James Webb Space Telescope (JWST) now offers the opportunity to probe this emission deep into the reionization epoch. We report the observations of eight quasars at z > 6.5 using the JWST/NIRCam Wide Field Slitless Spectroscopy as a part of the “A SPectroscopic survey of biased halos In the Reionization Era (ASPIRE)” program. Our JWST spectra cover the quasars’ emission between rest frame ∼4100 and 5100 Å. The profiles of these quasars’ broad Hβ emission lines span a full width at half maximum from 3000 to 6000 km s−1. The Hβ-based virial black hole (BH) masses, ranging from 0.6 to 2.1 billion solar masses, are generally consistent with their Mg ii-based BH masses. The new measurements based on the more reliable Hβ tracer thus confirm the existence of a billion solar-mass BHs in the reionization epoch. In the observed [O iii] λ λ 4960,5008 doublets of these luminous quasars, broad components are more common than narrow core components (≤ 1200 km s−1), and only one quasar shows stronger narrow components than broad. Two quasars exhibit significantly broad and blueshifted [O iii] emission, thought to trace galactic-scale outflows, with median velocities of −610 and −1430 km s−1 relative to the [C ii] 158 μm line. All eight quasars show strong optical Fe ii emission and follow the eigenvector 1 relations defined by low-redshift quasars. The entire ASPIRE program will eventually cover 25 quasars and provide a statistical sample for the studies of the BHs and quasar spectral properties.Peer reviewe

The Role Played by Theory of Mind and Empathy in the Feigning of Psychopathology

In this article, we hypothesized that in order to feign mental illness, one would need to have empathy and be able to understand other’s mental states. To test this hypothesis, we asked 432 healthy volunteers to feign depression, PTSD or schizophrenia while completing a self-report test that measures the severity of the feigned condition’s symptoms and the Inventory of Problems – 29 (IOP-29). Additionally, all participants were administered a theory of mind (ToM) task and an empathy measure with the request to respond truthfully. Results from a series of linear regression models revealed that higher cognitive empathy is associated with increased symptom endorsement on self-report symptom questionnaires and higher ToM abilities are associated with less credible feigned profiles, especially in the case of feigned depression

Quasar Island -- Three new z∼6z\sim6 quasars, including a lensed candidate, identified with contrastive learning

Of the hundreds of $z\gtrsim6$ quasars discovered to date, only one is known to be gravitationally lensed, despite the high lensing optical depth expected at $z\gtrsim6$. High-redshift quasars are typically identified in large-scale surveys by applying strict photometric selection criteria, in particular by imposing non-detections in bands blueward of the Lyman-$\alpha$ line. Such procedures by design prohibit the discovery of lensed quasars, as the lensing foreground galaxy would contaminate the photometry of the quasar. We present a novel quasar selection methodology, applying contrastive learning (an unsupervised machine learning technique) to Dark Energy Survey imaging data. We describe the use of this technique to train a neural network which isolates an 'island' of 11 sources, of which 7 are known $z\sim6$ quasars. Of the remaining four, three are newly discovered quasars (J0109-5424, $z=6.07$; J0122-4609, $z=5.99$; J0603-3923, $z=5.94$), as confirmed by follow-up Gemini-South/GMOS and archival NTT/EFOSC2 spectroscopy, implying a 91 per cent efficiency for our novel selection method; the final object on the island is a brown dwarf. In one case (J0109-5424), emission below the Lyman limit unambiguously indicates the presence of a foreground source, though high-resolution optical/near-infrared imaging is still needed to confirm the quasar's lensed (multiply-imaged) nature. Detection in the g band has led this quasar to escape selection by traditional colour cuts. Our findings demonstrate that machine learning techniques can thus play a key role in unveiling populations of quasars missed by traditional methods.Comment: 11 pages, 5 figures, 4 tables. Accepted 26 March 2024 for publication in MNRA