Laura Olivera Nieto (Spain)
laura.olivera-nieto @ mpi-hd.mpg.de
Very-high-energy emission from systems with relativistic jets
Description: The processes that lead to the acceleration of particles to very-high energies, together with the astrophysical sites where they may occur, are not very well understood. Since the discovery of cosmic rays -high energy particles that constantly reach the Earth from all directions - in 1912, the origin of the most energetic ones has been a mystery, due to deflections of their initial trajectories by magnetic fields. However, in principle, these high-energy particles might interact with radiation fields or matter present in the acceleration site. These interactions result in the production of gamma rays and neutrinos, which could be the key to pinpointing the so far unknown cosmic accelerators.
A good candidate for such sites are relativistic jets: highly collimated beams of matter moving at extremely high velocities. Typical examples of such jets are present in Active Galactic Nuclei and also, with smaller velocities, in microquasars. A better understanding of the physical conditions in such systems should lead to a more complete picture of jet occurrence, particle acceleration and, perhaps, shed some light on the processes that lead to the production of very-high energy cosmic rays.
The aim of my PhD work is to study the very-high-energy emission from such systems, and in particular from the microquasar SS 433, from which emission at energies above the TeV was recently detected by the HAWC Observatory. For this purpose, I will analyze data from the H.E.S.S. Telescopes and the HAWC Observatory in order to better understand the conditions at the source. Later on, and using this information I will try to model the emission from this and similar sources, with a special focus on the highest energies.
Supervisor: Jim Hinton (MPIK)