The study of Gamma-ray bursts (GRBs) is now in a great and unique period when both Swift and Fermi satellites are operational. The rapid response capability of the Swift satellite has led to a number of breakthroughs in the past decade. Meanwhile, the high energy (GeV) observation from Fermi satellite has opened a new window in exploring GRBs since its launch 6 years ago.

However, with all these great data collected from both Swift and Fermi, along with broad-band follow-up observations, yet a lot of problems remain unsolved and challenge various models. Some fundamental issues are still poorly understood, and, when existing questions are answered, new questions arise. Since this unique time, with two GRB satellites in the sky at the same time, can not last very long, it is crucial to study GRBs as detailed as possible before the two satellites pass their lifetime.

We invite authors to submit original research articles that focus on critical topics on GRBs, both observationally and theoretically. We are interested in articles that are related to either Swift or Fermi observations.

Potential topics include, but are not limited to:

• The origin of GRB prompt emission: composition of the jet, energy dissipation, particle acceleration mechanism, radiation mechanism, etc.
• The origin of high energy (GeV) photon, both in prompt phase and in afterglow phase
• All wavelength follow-up observations and various modeling explaining its broad-band spectral energy distribution
• Connections between GRB and Supernova
• Host galaxy properties and their relation with the birth of GRB