PhDs in Cosmic Microwave Background and Early Universe

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. For what concerns CMB, the SISSA Astrophysics group led by Carlo Baccigalupi, Francesca Perrotta, is directly in operating (Simons Array, Planck) and planned experiments (Simons Observatory, S4, LiteBird). Also, Carlo Baccigalupi coordinates the activities on cross-correlation between CMB and LSS for the forthcoming European Space Agency satellite, Euclid. Here below the list of available and ongoing PhD thesis projects on these matters. Support to these researches is given by the EU H2020 RadioForeground Grant (Simons Array, Simons Observatory), the ASI-COSMOS network of the Italian Space Agency (Simons Array, Simons Observatory), the INFN Indark Initiative (all projects), the 2015 PRIN (Euclid).

• Simons Array ongoing observations, to be completed withing 2020. Projects available on:

  - Data analysis and tools for map-making (Supervisors Carlo Baccigalupi, Davide Poletti)

  - B-mode reconstruction from multi-frequency data and foreground separation (Supervisors Carlo Baccigalupi, Davide Poletti)

  - Modeling and Characterization of diffuse Foreground Contamination to B-modes (Supervisors Carlo Baccigalupi, Nicoletta Krachmalnicoff)

  Collaborators at SISSA: Carlo Baccigalupi, Nicoletta Krachmalnicoff, Davide Poletti, Giuseppe Puglisi (ongoing PhD Project). Main external collaborators: APC (Paris) group led by Radek Stompor, IC (London) group led by Andrew Jaffe.


• Simons Observatory and future CMB experiments. Observations planned to begin in 2019 and last for 3 years. Projects available on:

  - Foreground Data Analysis for existing Datasets (Supervisors Carlo Baccigalupi, Francesca Perrotta, Nicoletta Krachmalnicoff)

  - Polarized Foreground Modeling (Supervisors Francesca Perrotta, Nicoletta Krachmalnicoff)

  - Development of Foreground Separation Data Analysis Algorithms (Supervisors Carlo Baccigalupi, Davide Poletti)

  - Development of de-Lensing Data Analysis Algorithms (Supervisors Carlo Baccigalupi)

  Collaborators at SISSA: Carlo Baccigalupi, Nicoletta Krachmalnicoff, Davide Poletti, Francesca Perrotta, Piero Ullio, Jiaxin Wang (ongoing PhD work). Main external collaborators: Ettore Carretti for the S-PASS Collaboration (INAF-CA), APC (Paris) group led by Radek Stompor, IC (London) group led by Andrew Jaffe.


• CMB Weak Lensing. Projects available on:

  - Numerical Simulations of CMB Weak Lensing for Euclid

  Collaborators at SISSA: Carlo Baccigalupi, Andrea Lapi, Matteo Viel. Main external collaborators: Carmelita Carbone (Milano), Nabila Aghanim and Giulio Fabbian (IAS, Paris)


• CMB Cross-Correlations. Projects available on:

  - CMB anisotropy and lensing Cross-Correlation with LSS tracers

  - CMB Reionization

  Collaborators at SISSA: Carlo Baccigalupi, Luigi Danese, Andrea Lapi, Francesca Lepori (ongoing PhD project), Anirban Roy (ongoing PhD Project), Matteo Viel. Main external collaborators: Federico Bianchini (Melbourne, Australia), Giulio Fabbian (IAS, Paris), Joaquin Gonzalez-Nuevo (Santander, Spain)


• Modeling the polarized emission from Radio Galaxies

  Radio Loud Glaxies have been proven to be the main extragalactic foreground component that will be detected in the next CMB surveys sensitive to polarization. The statistical study and the knowledge of the polarization properties of such sources will be, on one hand, a fundamental tool to remove this contaminant from the CMB polarization maps. On the other hand, the characterization of RL polarization properties will shed light on the underlying radio emission models, helping to understand the confinement mechanism of jets through a possible magnetic field in the AGN hosting galaxy.

  Main collaborators at SISSA: Francesca Perrotta, Annalisa Celotti

Galaxy Formation and Evolution

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 wealth of current observations concerning galaxies, black holes, and active galactic nuclei over the whole electromagnetic spectrum and across cosmic times. We are strongly focused on the cosmological exploitation of galaxy survey data to help understanding the nature of dark matter, dark energy, and gravity.

Main collaborators in SISSA: Carlo BACCIGALUPI (AP), Alessandro BRESSAN (AP), Annalisa CELOTTI (AP), Adriana LORENZO-CACERES (AP postdoc), Francesca PERROTTA (AP), Paolo SALUCCI (AP), Riccardo VALDARNINI (AP), Matteo Viel (APP).

Recent former students: Jingjing SHI (Univ. Beijing, China and Univ. Perth, Australia), Federico BIANCHINI (Univ.Melbourne, Australia), Claudia MANCUSO (INAF-IRA, Bologna,Italy), Rossella AVERSA (CNR, Trieste,Italy).

Financial support: PRIN MIUR, 2015 Euclid grant, PRIN INAF, 2017 SKA grant, EU H2020, RadioForeground Grant, ASI-COSMOS network, INFN QGSKY, and InDARK Initiatives,Spanish MINECO I+D 2015 project.

• Galaxy formation

  - coevolution of galaxies and supermassive black holes

  - analysis and interpretation of sub-mm, far-IR, and radio survey data

  - the origin of angular momentum in galaxies

  - chemical and dust production in galaxies

  - gravitational waves from galaxy and supermassive black hole mergers



• Dark matter halos

  - halo statistics via excursion set formalism

  - models for dynamical relaxation of halos

  - dark matter distribution via weak and strong gravitational lensing

  - simulated halo catalogs



• Cosmology, gravity and large-scale structure

  - cosmic reionization history

  - cross-correlation studies of CMB and LSS observables

  - probing dark energy and gravity via weak gravitational lensing

  - foreground cleaning of CMB maps and delensing



• Galaxy clusters

  - thermodynamics of the intracluster medium

  - astrophysics of cluster outskirts

  - AGN feedback in groups and clusters

  - thermal conduction and turbulence in clusters

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 (see, for instance, here) and group of galaxies (Paolo Salucci, Andrea Lapi)
• The nature of the dark matter phenomenon: leads from observations and from galactic gamma-ray emissions and underground detections (Paolo Salucci)
• Ellipticals: crossroads between DM halos, their inner stellar spheroid and their central supermassive black holes (Luigi Danese, Paolo Salucci)
• The change of paradigm: from LCDM to LWDM (Paolo Salucci, Luigi Danese, Andrea Lapi )
• Dark matter halo formation and statistics (Luigi Danese, Paolo Salucci, Andrea Lapi)

Gravitation theory

Almost 100 years after Einstein introduced General Relativity, the theory still remains puzzling. Systems were gravity is strong, such as compact stars and black holes, and the phenomena taking place in their vicinity can provide new insight in both astrophysics and fundamental physics. The recent detection of Gravitational Waves from Black-Hole and Neutron Star systems opens unprecedented windows on the regime of strong gravity, and enforces the need to study emitters and progenitors in astrophysical systems. Moreover, the thorny issues of quantum gravity and potentially even classical deviations from General Relativity are most pertinent than ever. The group at SISSA is active in the following directions:

• Astrophysics of Emitters and Progenitors (Alessandro Bressan, Stefano Liberati)
• Alternative and Analogue Theories of gravity, Quantum Gravity and Astroparticle (Stefano Liberati, see here)

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 (Annalisa Celotti, Luigi Danese, Andrea Lapi), ongoing PhD Thesis by Elias Kammoun
• Accretion onto supermassive black holes (Annalisa Celotti, Luigi Danese, Andrea Lapi)
• Gamma-ray bursts (Annalisa Celotti, Lara Nava), ongoing PhD Thesis by Gor Oganesyan
• Extragalactic backgrounds (Annalisa Celotti, Luigi Danese)

Large Scale Structure

Present Large Scale Structure and Galaxy Cluster simulations in cosmology are compared with data from existing and planned (Euclid) surveys, allowing to gain unprecedented insight into the role of hydrodynamics, the main properties and dynamics of the Dark Matter and Dark Energy, as well as to constrain Gravity Modifications. The LSS group at SISSA is active in the following directions:

• Large scale parallel hydrodynamical simulations of GCs (Riccardo Valdarnini)
• X-ray properties of GCs (Riccardo Valdarnini)
• Turbolence in GCs and Sunyaev Zel'dovich signal (Riccardo Valdarnini)
• LSS, gravity modifications and screening mechanisms (Carlo Baccigalupi, Stefano Liberati, Matteo Viel, Eleonora Villa), ongoing PhD Theses by Francesca Lepori, Riccardo Murgia,
• Weak lensing in N-body simulations (Carlo Baccigalupi, PRIN Post-Doc to be selected within 2017)
• Interplay between Astrophysical Tracers, CMB lensing and Constraining Power on Dark Energy, Matter (Carlo Baccigalupi, Andrea Lapi, Matteo Viel), ongoing PhD Theses by Farida Farsian, Anirban Roy
• Preparatory work for the Euclid Satellite mission for the Cross-Correlation with CMB data (Carlo Baccigalupi, Andrea Lapi, Matteo Viel, PRIN Post-Doc to be selected within 2017)

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.

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

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