Lyman-alpha forest -- is the absorption produced by neutral hydrogen seen in the spectra of background quasars. I am interested in using the Lyman-alpha forest to recover the linear dark matter power spectrum at scales of 1-40 comoving Mpc which are not probed by other observables.
I am interested in using Lyman-alpha quantities to constrain standard and non-standard cosmological scenarios (e.g. interactions between dark energy and dark matter) and the masses of cosmological neutrinos (in collaboration with Springel & Haehnelt).
Cosmological parameters estimation -- When the dark matter power spectrum inferred from Lyman-alpha quasar spectra is combined with the Cosmic Microwave Background data we can get tight constraints on cosmological parameters (sigma_8, n and its running), on slow-roll inflationary models, on the mass of warm dark matter particles such as light gravitinos or sterile neutrinos.
Warm Hot Intergalactic Medium -- I am currently using hydro-dynamical simulations and the Tully catalog of galatic luminosity density in the local universe to study the distribution of warm-hot intergalatic medium and its detectability, focussing in particular on GRBs. I am also addressing the impact of several different feedback mechanisms on the low redshift IGM.
The UV background and metal enrichment -- I am using hydro-dynamical simulations to give constraints on the amplitude and shape of the UV background and on the metal enrichment at z=3. I rely on a modified version of the hydrodynamic code (G-II) that
incorporates a chemodynamical model with feedback recipes (work in collaboration with Tornatore, Tescari, Borgani, Cristiani, D'Odorico)
The nature of dark matter -- I am using hydro-dynamical simulations and high resolution data to constraints the properties of dark matter at the small scales (cold/warm dark matter and sterile neutrinos).
Large-scale structure/CMB cross correlation I am investigating cross-correlation of the Lyman-alpha forest flux with CMB lensing and of the quasar distribution with CMB temperature. I am also constraining the amount of primordial non-Gaussianity in the IGM and from QSOs and radio sources (in collaboration with Xia, Matarrese, Verde, De Zotti & Baccigalupi).
Effects of massive neutrinos on the large-scale structure of the Universe Marulli, Federico; Carbone, Carmelita; Viel, Matteo; Moscardini, Lauro; Cimatti, Andrea PREPRINT arXiv 1103.0278 -- 2011MNRAS.418..346M .
Massive Neutrinos and the Non-linear Matter Power Spectrum Bird, Simeon; Viel, Matteo; Haehnelt, Martin G. PREPRINT arXiv 1109.4416 -- 2011MNRAS in press .
Constraints on primordial non-Gaussianity from large scale structure probes
Xia, Jun-Qing; Baccigalupi, Carlo; Matarrese, Sabino; Verde, Licia; Viel, Matteo PREPRINT arXiv 1104.5015 -- 2011JCAP...08..033X .
The Non-Linear Matter Power Spectrum in Warm Dark Matter Cosmologies
Viel, Matteo; Markovic, Katarina; Baldi, Marco; Weller, Jochen PREPRINT arXiv 1107.4094 -- 2011 MNRAS in press .
Cosmic evolution of the C IV in high-resolution hydrodynamic simulations
Tescari, E.; Viel, M.; D'Odorico, V.; Cristiani, S.; Calura, F.; Borgani, S.; Tornatore, L. PREPRINT arXiv 1007.1628 --
2011MNRAS.411..826T .
The effect of neutrinos on the matter distribution as probed by the Intergalactic Medium Viel, Haehnelt, Springel PREPRINT arXiv 1003.2422 --
2010JCAP...06..015V .