Lecture by Brenda Dingus – Niels Bohr Institute - University of Copenhagen

Niels Bohr Institute > Calendar > 2010 > Lecture by Brenda Dingus

Lecture by Brenda Dingus

Brenda Dingus, cospokesperson of the High Altitude Water Cherenkov (HAWC) observatory. You can learn more about the project at www.hawc-observatory.org

HAWC is beginning construction soon and will make detailed observations of 100 GeV-100TeV cosmic rays and gamma rays.

Gamma-Ray Emission from the Milky Way Probing the Origin of Cosmic Rays
Cosmic rays were discovered nearly 100 years ago. These primarily hadronic particles have been measured in the near Earth environment, but we have not been able to determine their origin primarily because magnetic fields deflect the cosmic rays in random directions.

However, gamma rays are produced by cosmic rays interacting near their sources and as they propagate through the Galaxy. The plane of the Milky Way is a bright diffuse source of GeV-TeV gamma rays.

The Milagro Gamma-Ray Observatory

The Milagro observatory has measured this diffuse gamma ray flux which is much larger than expected given the local cosmic ray measurements. Deeper observations with current and future observatories will remove more of the unresolved localized source contributions and allow spectral measurements of the diffuse gamma-ray emission. Different spectra as well as a different spatial morphology are expected for different contributions to the gamma-ray flux. For example, the higher the energy of the gamma rays the more likely the gamma rays are produced by hadrons. The High Altitude Water Cherenkov (HAWC) observatory, a next generation version of Milagro, will have the sensitivity to observe these highest energy gamma rays and shed light on the origin of cosmic rays.