Galaxy Evolution and Physical Cosmology

Our team aims at investigating the complex processes leading to the formation and evolution of galaxies, galaxy systems, and supermassive black holes in a cosmological framework. To this purpose, we develop physical models to interpret and understand the astrophysics of galaxies and black holes across cosmic times, exploiting their emission over the whole electromagnetic spectrum and in gravitational waves. We are also strongly focused on the theoretical development of novel cosmological models and on the analysis of small- and large-scale structure data to help understanding the fundamental nature of dark matter, dark energy, and gravity.

PI: Andrea Lapi

Main collaborators in SISSA: Carlo BACCIGALUPI (APC), Alessandro BRESSAN (APC), Mario SPERA (APC), Paolo SALUCCI (APC), Samuele SILVERAVALLE (APC Postdoc), Gayathri GURURAJAN (APC Postdoc), Sandeep HARIDASU (APC Postdoc), Tommaso RONCONI (APC Postdoc), Lumen BOCO (APC Postdoc), Marcos MUNIZ CUELI (APC Postdoc), Matteo VIEL (APP), Stefano LIBERATI (APP).

Ph.D. students: Michele BOSI, Giovanni ANTINOZZI, Meriem BEHIRI, Francesco GABRIELLI, Martina TORSELLO, Cecilia SGALLETTA, Minahil Adil BUTT, Francesco BENETTI, Carlos ALONSO ALVAREZ

Former Ph.D. students: Maria Vittoria ZANCHETTIN (2024), Massimiliano PARENTE (2024), Yacer BOUMECHTA (2024), Giulia CAPURRI (2023), Giovanni GANDOLFI (2023), Marika GIULIETTI (2023), Alex SICILIA (2023), Giulio SCELFO (2022), Lumen BOCO (2021), Lara PANTONI (2021), Lorenzo ZANISI (2021), Tommaso RONCONI (2020), Sabyasachi GOSWAMI (2020), Anirban ROY (2019), Jingjing SHI (2017), Isabella Paola CARUCCI (2017), Federico BIANCHINI (2016), Claudia MANCUSO (2016), Rossella AVERSA (2015), Zhen-Yi CAI (2012), Lulu FAN (2011), Alessandro PAGGI (2010), Michael COOK (2009), Chiara TONINI (2007), Jirong MAO (2006).

Involvement in international projects: SKAO, Athena, Euclid, Herschel, LISA, Einstein Telescope.

Financial support (most recent): PRIN MUR 2022 "Charting Unexplored Avenues in Dark Matter", Fondazione ICS-Spoke3-NGEU "Astrophysics and Cosmos Observations", INAF large grant 2022 "MeerKAT and LOFAR Team up: a Unique Radio Window on Galaxy/AGN co-Evolution", H2020-ITN "BiD4BEST:Big Data Application for Black Hole Evolution Studies", MUR-PCS "Data Science methods for MultiMessenger Astrophysics and Multi-Survey Cosmology", PRIN MUR 2017 "Opening the ALMA window on the cosmic evolution of gas, stars and supermassive black holes", INFN QGSKY Initiative.

Related interdisciplinary groups in Data Science and Galaxy/Black Hole Evolution:

• Big Data for Black Hole Evolution Studies - Bid4BESt
• Galaxy Observational and Theoretical Astrophysics - GOThA

  
  Main research topics and available thesis projects:

  • Galaxy formation
    • galaxy assembly theories
    • high-redshift galaxies and AGNs
    • coevolution of galaxies and (super)massive black holes
  
  
  • Cosmology and large-scale structure
    • cosmological models
    • cross-correlation of cosmic fields
    • simulated halo and galaxy catalogs
  
  
  • Gravitational Waves
    • cosmological GW rates ad backgrounds
    • multimessenger astrophysics of transient sources
    • formation of BH seeds and GW emission from intermediate/extreme mass ratio inspirals
  
  
  • Dark matter and gravity
    • modified gravity frameworks
    • (non)standard dark matter scenarios
    • halo mass function theories
  
  
  • Galaxy clusters
    • clusters as probes of dark matter and gravity
    • thermodynamics of the intracluster medium
    • protoclusters at high-z
  
  
  • Data science in astrophysics and cosmology
    • data-driven, (semi)empirical models of galaxy evolution
    • Bayesian inference, machine and deep-learning methods
    • HPC, vectorized and parallel programming

Early Universe and CMB Data Analysis

The Early Universe is nowadays probed with unprecedented precision by Cosmic Microwave Background (CMB) and Large Scale Structure (LSS) experiments. This poses severe challenges to our comprehension of the physical processes occurred in the Early Universe, as well as the nature of the Dark Cosmological Components. The SISSA CMB group, led by Carlo Baccigalupi and Nicoletta Krachmalnicoff, has coordination roles in data analysis, pipeline preparation, data exploitation and interpretation in operating (POLARBEAR, Simons Observatory) and planned (CMB-S4, LiteBIRD) experiments. Also, Carlo Baccigalupi coordinates the activities on cross-correlation between CMB and LSS for the European Space Agency Euclid satellite.

Post-docs: Leo Vacher, Alessandro Carones

Ph.D. students: Jian Yao, Florie Carralot, Claudio Ranucci, Sijil Jose, Aliza Mustafa

Main research topics and available thesis projects:

• Measuring the amplitude of Cosmological Gravitational Waves through the B-modes of CMB polarization
• Measuring the behavior of Dark Energy, responsible for the Cosmic Acceleration, through the Gravitational Lensing effect on CMB and LSS
• Exploiting Data Science for the design of new algorithms for the analysis at all levels of the data reduction of the quoted experiments.

Stellar Structure and Evolution

Stellar evolution keeps a unique role for deciphering the visible properties of the universe, from the solar neighborhoods to the primeval galaxies. A new Renaissance for the stellar structure theory is approaching, due to the challenging results of asteroseismology, that are disclosing the invisible star's secrets, and to the beginning of the multi-messenger astronomy with the detection of gravitational waves from merging compact stellar remnants and their follow-ups.

PI: Alessandro Bressan

Main collaborators in SISSA: Guglielmo Costa (PhD student), Sabyasachi Goswami (PhD student), Milena Valentini (PhD student), Mirouh Giovanni (APC, postdoc), Luigi Danese (APC), Antonio Lanza (APC), Andrea Lapi (APC), Francesca Perrotta (APC), Paolo Salucci (APC).

Recent former students: Yang Chen (Univ. Padova), Xiaoting Fu (Univ. Bologna), Ambra Nanni (Univ. Padova), Ikechukwu Anthony Obi (Univ. Enugu, Nigeria) , Alessandra Slemer (Univ. Padova), Jing Tang (NAO, Beijing), Alessandro Trani (Univ. Tokyo).

Financial support: PRIN INAF, 2015 Euclid grant, ERC "STARKEY" (P.I. Paola Marigo, Univ. Padova).

• Stellar evolution for population synthesis studies
  • stellar physics (mixing, rotation, mass-loss, element abundances)
  • evolutionary tracks , binary evolution
  • resolved stellar populations
  • demography of compact remnants
  • gravitational waves from stellar black holes and neutron star mergers


• Stellar dust ejecta
  • dust formation in circumstellar envelopes
  • stellar populations in the mid infrared


• Spectro-photometric evolution of galaxies
  • chemical evolution of galaxies
  • effects of dust reprocessing
  • panchromatic spectra of galaxies
  • properties of the inter-stellar medium

High Energy Astrophysics

The formation and the evolution of extremely compact stellar objects and Black Holes in the Universe are signaled by exceptional phenomena such as production of particles accelerated to energies much higher than those reachable by the most powerful accelerators on Earth. Often these particles are collimated in extremely energetic jets. Extraordinary X-ray and gamma-ray luminosity is also associated with these objects. High Energy Astrophysics is devoted to study the extremely energetic phenomena occurring in the Universe, in order to understand these extraordinary cosmic settings and to test the fundamental physics at its frontiers.

• Active galactic nuclei (in coll. with Luigi Danese, Andrea Lapi)
• Accretion onto supermassive black holes (in coll. with Luigi Danese, Andrea Lapi)
• Gamma-ray bursts (in coll. with Lara Nava)
• Extragalactic backgrounds (in coll. with Luigi Danese)

Dark Matter

Dark matter is a main protagonist in Cosmology. Its presence, proven by observations, implies the existence of physics yet undiscovered, moreover such a component is likely to rule the formation and the evolution of any Cosmological Structure. In galaxies, groups and clusters of glaxies, the observed ordinary baryonic matter, gas and stars, had, over the whole history of the Universe, a complex interplay with this invisible component. The detailed lines of research are:

• The distribution of dark and visible matter in galaxies (in coll. with Andrea Lapi)
• The nature of the dark matter phenomenon: leads from observations and from galactic gamma-ray emissions and underground detections
• Ellipticals: crossroads between DM halos, their inner stellar spheroid and their central supermassive black holes (in coll. with Luigi Danese)
• The change of paradigm: from LCDM to LWDM
• Dark matter halo formation and statistics (in coll. with Andrea Lapi)

Gravitational Wave Astrophysics

On September 14 2015 the LIGO interferometers caught the first direct detection of gravitational waves (GWs). This was a historic breakthrough and, for the first time, we had access to a new information medium to investigate the Universe. While the number of GW detections continuously increases, the astrophysical origin of the GW events is still shrouded in mystery. Who are the progenitors of GW sources? Where do they form? How do they evolve? How do two compact objects (e.g. black holes, neutron stars) end up so close to each other to merge within the age of the Universe? What do we expect to detect through the next generation of GW interferometers? The goal of our research group is to provide an answer to these questions. To do that, we develop and adopt up-to-date codes to study the astrophysics of compact objects, from the evolution of their progenitor stars in isolation to the formation of merging pairs in dense stellar environments.

Our new research team is deeply integrated within the whole SISSA-APC group and it has strong connections with Prof. Alessandro Bressan, Prof. Andrea Lapi, and their collaborators. We are happy to accept students and young researchers who are willing to get their hands dirty with GW astrophysics and high-performance computing.

Involvement in international projects: LIGO-Virgo-KAGRA collaboration, Einstein Telescope, AMUSE

• the evolution of single stars through, e.g., the PARSEC code (in coll. with Prof. Alessandro Bressan research group - SISSA);
• the birth, life, and death of binary stars through, e.g., the SEVN code (in coll. with Prof. Michela Mapelli research group - Uni. Padova);
• the chaotic dynamics of hierarchical few-body systems through, e.g. the TSUNAMI code (in coll. with Dr. Alessandro Trani - Uni. Tokyo);
• the interplay between stellar evolution and stellar dynamics through our own, brand-new, GPU-accelerated code ``ISTEDDAS''.

Astrochemistry and Astrobiology

Astrobiology is a multidisciplinary science facing one of the most fundamental topics nowadays, the origin of life. It lies at the intersection of astronomy, physics, chemistry, geology, and biology. Initially organic compounds form in the interstellar medium, and their interaction with radiation and surfaces - from grains of sand to growing planetesimals - facilitates the steady growth of complex molecules. In this way, they form chemical systems (prebiotic molecules) that can combine to create genetic material and metabolism. We focus on the search of complex organic molecules in the interstellar medium and, particularly, on the search of chiral molecules (molecules that can exist in two forms which are mirror images of each other, named enantiomers), which have a particular importance for life. Indeed, any biological system on Earth relies on key chiral molecules (sugars, aminoacids, nucleic acids) which, remarkably, exist almost exclusively as single enantiomers: homochirality seems to be a striking signature of life. The search for chiral molecules and the possible measurements of their enantiomeric excess in astronomical compounds in the ISM will proceed through the spectroscopical analysis of IR and sub-mm data from existing radiotelecopes and interferometers, such as ALMA.

Main collaborators: : Laura Silva & Giovanni Vladilo (INAF/OATS, Trieste, Italy), Marcella Massardi (INAF/IRA, Bologna, Italy), Massimo Maris (Univ. Bologna, Italy), Alessandra Magistrato (INFN Trieste, Italy)

• identification of complex organic molecules in the ALMA surveys, search for chiral molecules


• polarization-based methods to characterize an enantiomeric imbalance in an astronomical molecular cloud and development of new techniques.