Recently the Fermi-LAT has detected approximately 35 GRBs with gamma ray emission above 100 GeV.  Several models have been proposed to explain this high-energy emission, including hadronic models, where photon-hadron process produces charged pions and subsequently the 100 TeV neutrinos.

We are using the data from Fermi-GBM to calibrate the photon (representing electrons) energy content of the GRB jet. Given the non-detection of GRB neutrinos, we aim to put upper limits on the proton (turned pion) energy content.

The same photon-hadron process that is expected to produce the charged pions and subsequently the 100 TeV neutrinos, would also generate neutral pions that decay to photons of similar energy.

These high-energy photons have been hypothesized to cascade through pair production processes down to the GeV regime, where they can escape the jet and be observed by Fermi-LAT.

Within this scenario, we are using the observed GeV photon fluence to put another upper limit on the energy content of the protons in the jet.