Paul Sommers

Titles

Adjunct Professor of Physics

Professor of Physics (retired)

Professor of Astronomy and Astrophysics (retired)

Education

University of California, Berkeley (B.A., Physics), 1968

University of California, San Diego (M.S., Physics), 1969

University of Texas, Austin (Ph.D., Relativity), 1973

Specialties:

Particle Astrophysics

• Theoretical
• Experimental

Particles & Fields

• Theoretical
• Experimental

Honors and Awards

• Fellow of the American Physical Society

Selected Publications

1. "Measurement of the proton-air cross-section at sqrt(s) = 57 TeV with the Pierre Auger Observatory,"The Pierre Auger Collaboration, Phys. Rev. Lett. 109, 062002 (2012).
2. "Ultra-High Energy Cosmic Rays: Observational Results," Paul Sommers, Astroparticle Physics, vol 39-40, pp 88-94 (2012).
3. "Measurement of the cosmic ray energy spectrum using hybrid events of the Pierre Auger Observatory," M. Settimo for the Pierre Auger Collaboration, Eur. Phys. J. Plus 127, 87 (2012).
4. "The Rapid Atmospheric Monitoring System of the Pierre Auger Observatory," The Pierre Auger Collaboration, JINST 7, P09001 (2012).
5. "Antennas for the Detection of Radio Emission Pulses from Cosmic-Ray induced Air Showers at the Pierre Auger Observatory," The Pierre Auger Collaboration, JINST 7, P10011 (2012).
6. "Results of a self-triggered prototype system at the Pierre Auger Observatory for radio-detection of air showers induced by cosmic rays," The Pierre Auger Collaboration, JINST 7, P11023 (2012).
7. "A Search for Point Sources of EeV Neutrons," The Pierre Auger Collaboration, ApJ 760, 148 (2012).
8. "Large scale distribution of arrival directions of cosmic rays detected above 1018 eV at the Pierre Auger observatory," The Pierre Auger Collaboration, ApJ Suppl 203, 34 (2012).
9. "Ultra-High Energy Neutrinos at the Pierre Auger Observatory," The Pierre Auger Collaboration, Advances in High Energy Physics, in press, (2013).
10. "Constraints on the origin of cosmic rays above 1018 eV from large scale anisotropy searches in data of the Pierre Auger observatory," The Pierre Auger Collaboration, ApJ Lett., 762, L13 (2013).

Research Interests

My quest has been to understand the properties and the origins of the highest energy particles in the universe. These cosmic rays are fully ionized atomic nuclei with energies in excess of 10 Joules per particle. How and where they are produced in the cosmos is a long-standing mystery. Approximately 400 physicists from 18 countries have joined the Pierre Auger Collaboration to solve this puzzle. At Penn State, I was the associate director of the Institute for Gravitation and the Cosmos and a member of its Center for Particle and Gravitational Astrophysics.  I have special interest in the Astrophysical Multimessenger Observatory Network (AMON) and the possibility that an ultra-high energy neutron might be detected by Auger at the same time and from the same direction as other astroparticle messengers originating at some cosmic burst in the Galaxy.