NPAC (Nuclear/Particle/Astro/Cosmo) Forums
Organized by: Prof. Lu Lu
Events on Thursday, December 16th, 2021
- Multimessenger constraints on intergalactic magnetic fields
- Time: 2:30 pm
- Speaker: Rafael Alves Batista, Universidad Autónoma de Madrid
- Abstract: The most traditional and promising way to probe intergalactic magnetic fields (IGMFs) is using gamma rays produced in electromagnetic cascades initiated by high-energy gamma rays in the intergalactic space. Because the charged component of the cascade is sensitive to intervening magnetic fields, it is possible to probe IGMFs by combining spectral, temporal, and angular information from distant sources of high-energy gamma rays such as blazars. High-energy cosmic rays, too, being charged, can provide insights into IGMFs, although this is more complicated given that their sources remain to be found. At the dawn of the multimessenger era, a third probe can be used to help us solve this puzzle: neutrinos. In this talk I will firstly motivate the quest for understanding cosmic magnetogenesis and review the status of studies of IGMFs with neutrinos, cosmic rays, and gamma rays. I will then describe a novel multimessenger strategy for probing IGMFs using combined gamma-ray and neutrino observations from flaring objects. Finally, I will present the first constraints on the coherence length of IGMFs obtained with this method.
- Host: Ke Fang