Lara Nava

22/05/2017

AstroFIt 2 – COFUND fellow since March 1, 2017.

INAF Research Centre: Osservatorio Astronomico di Brera, Osservatorio Astronomico di Trieste

Email: lara.nava at inaf.it

Curriculum vitae

Papers/Publications:

Project title: HALPES – Hadronic And Leptonic Processes in Extragalactic Sources: a multi-messenger, multi-source approach to unveil the origin of γ-ray radiation and neutrinos

Abstract:

The physics of particle acceleration at collisionless shocks and their transport in the ambient medium are among the most longstanding unsolved problems and open questions in High-Energy Astrophysics. These processes regulate the radiation output at the highest (GeV-TeV) energies from the most extreme high-energy sources. Observations at γ-rays can then be used as a tool to constrain the physical processes that play a role in shaping the emission. The effectiveness of this approach is however limited by the still poor understanding of γ-ray spectra: our lack of knowledge on the underlying physical mechanisms coupled with large uncertainties on ambient photon, matter, and magnetic fields, does not allow to disentangle between competing models (e.g. leptonic and hadronic). Recent improvements in the quality and number of available γ-ray detections are now starting to shed some light on the problem. Also, the detection of extragalactic ~PeV neutrinos by the IceCube experiment is providing us with new tools: neutrinos reveal the relevance of hadronic processes, and their combined use with γ-ray observations must be now fully exploited in order to progress beyond the state-of-the-art.

I seek to attack the problem by considering three different classes of extragalactic sources (Gamma Ray Bursts, Blazars, and StarBurst galaxies) with the aim to answer two fundamental questions: the respective roles played by leptonic and hadronic processes in producing the GeV-TeV emission, and the production level of ~PeV neutrinos. Observations coupled to the developed theoretical models will be used to constrain the unknown quantities (configuration and strength of ambient radiation and magnetic fields) and underlying physics (collisionless shocks, particle propagation and coupling with photon, matter and magnetic fields). A tailored approach for each class of sources will be adopted, with the aim of going beyond the respective state-of-the-art and build a coherent global picture.