22-24 May 2013
Physics Department, University "La Sapienza", Roma, Italy
Europe/Rome timezone

An exploration of hadronic interactions in blazars using IceCube

22 May 2013, 16:30
Aula Giorgio Careri (first floor) (Physics Department, University "La Sapienza", Roma, Italy)

Aula Giorgio Careri (first floor)

Physics Department, University "La Sapienza", Roma, Italy


Ms Celine Tchernin (University of Geneva)


The relativistic electrons responsible for the observed broad band synchrotron / inverse Compton emission from blazars can be either directly accelerated at the source (primary electrons) or produced in result of interactions of high energy protons with surrounding medium (secondary electrons). If the observed electromagnetic emission from blazars is produced by secondary electrons, neutrino emission is also expected. Using the measurements of electromagnetic luminosity of blazars with the Fermi/LAT telescope in the GeV band, we estimate expected neutrino flux from brightest blazars. We compare this estimate to the neutrino flux upper limits imposed by IceCube (in the IC-40 configuration) to set constraints on the parameters of the spectrum of accelerated protons: the spectral index(gamma) and the high-energy cutoff(Emax). We find that if the assumption of hadronic origin of electromagnetic emission is correct, blazars should accelerate protons to very-high energy (Emax>1e18 eV) with a hard spectrum (gamma<2).

Primary author

Ms Celine Tchernin (University of Geneva)


Prof. Andrii Neronov (University of Geneva) Dr Juan Antonio Aguilar Sanchez (University of Geneva) Prof. Teresa Montaruli (University of Geneva)

Presentation Materials