The doctoral fellowship programme INPhINIT ”la Caixa” is devoted to attracting talented Early-Stage Researchers of any nationality to pursue their PhD studies in the best Spanish and Portuguese research centres and units with excellence distinction.

Research Project / Research Group Description

VHE gamma-ray observations of blazars in last 20 years expanded the horizon of detected sources in number (from ~5 sources to ~80) distance (up to z=0.944) and class (BL Lacs, FSRQ, radio-galaxies). Many crucial questions remain open on the jet physics: processes involved in jet launching and acceleration, role of hadrons, the connection of blazars to ultra-high-energy cosmic rays, the location of the site of photon emission in different classes of sources and source states.

The  research project focuses on the study of AGN jet emission in VHE γ-rays together with  multi-wavelength (MWL) data including polarimetry. The aim is to study jets from their broad-band spectral energy distribution (SED) at single epoch, and from the time evolution in flux, spectrum and polarization of MWL emission. This can also contribute to cosmological topics such as the study of Inter Galactic Magnetic Fields (IGMF), or evolution of the Extragalactic Background Light (EBL) through cosmic ages. The program will be hosted in the VHEGA (Very High Energy Group for Astrophysics) Group (PIs: Iván Agudo & Rubén López-Coto ; also members Dr. M. Bernardos and PhD student J. Escudero), participating to CTA, LST and MAGIC. The team has expertise on MWL blazar studies including also optical and mm polarimetry; in this field the group leads long-term programs for monitoring and Target of Opportunity observations of blazars: the POLAMI program at the IRAM 30m telescope in Sierra Nevada, and the TOP-MAPCAT program at the 2.2m optical telescope in Calar Alto (Almeria), as well as parallel programs from the 1.5m and 0.9m telescopes at the Observatory of Sierra Nevada (OSN), an IAA internal facility. Moreover, in January 2022 the IXPE satellite, first X-ray polarimeter ever, was launched, and the Group Leader is a member of the IXPE collaboration. IXPE data on blazars will be sure available along the timespan of the PhD fellowship. 

Job position description

The InPhINIT fellow will grow a state-of-the-art background in the fields of blazar physics, with focus on the VHE data analysis, on the exploitment of MWL data and on the theory-data comparison for emission models. Cosmological and fundamental implications will be a natural focus as well. This project will be developed in the context of top-class large international collaborations, a fertile and world-wide intellectual environment; an ambitious learning curve is easily at hand for the INPhINIT fellow. It will profit from direct availability of unique VHE datasets from MAGIC and LST, but also from in-house availability of polarimetric data in the optical (TOP-MAPCAT, OSN) and mm wavelengths (POLAMI). The operatioon since January 2022 of the IXPE X-ray polarimeter (NASA+ISA, with participation of our group from Spain) with a dedicated blazars program makes even more timely this project.

Plan

Y1 Introduction to Cherenkov astronomy; MAGIC and LST observations and data analysis software; blazar VHE data analysis. AGN phenomenology, emission models.

Selection of a main theme within the blazar studies with VHE γ-rays.

Y2  Start working on MWL datasets, including IXPE X-ray polarimetry. Works periodically shown to MAGIC/LST and/or IXPE blazar groups. Start presenting at conferences. Join MAGIC calls for proposals and if needed apply for time at external facilities (e.g. Swift). Introduction to cosmology with blazars: EBL, IGMF. Introduction to ALP and LIV studies.

Y3 Projects finalized, paper drafts shared within MAGIC/LST and IXPE and submitted when blessed. Goal is 3 papers with main contribution from the student. Journals: ApJ, A&A, MNRAS.  Finalization of papers, thesis writing. Dissemination.

Y1-3 

• Inclusion in the CTA, LST and MAGIC Consortia, as well as IXPE, with participation to:
  • CTA-LST prototype and/or MAGIC observing shifts
  •  development and validation of CTA and LST software
  •  the MAGIC and IXPE blazar science working groups