James M. Matthews, Ph.D.

James M. Matthews, PhD
Professor of Physics

Ph.D., 1984 - University of Wisconsin-Madison

Louisiana State University
Department of Physics & Astronomy
347 Nicholson Hall, Tower Dr.
Baton Rouge, LA 70803-4001
(225) 578-8598-Office

Research Interests

Experimental Astrophysics/Particle Physics

Prof. Matthews’ research involves the experimental study of the highest energy cosmic rays at the Pierre Auger Observatory in western Argentina. His group at LSU has been engaged in diverse projects on hardware, electronics, data analysis, and computer simulations. This project is an international collaboration of over 500 scientists and engineers.  Prof. Matthews is the Co-Spokesperson of the Collaboration and a Fellow of the American Physical Society.  He has been a part of the Auger effort since its inception in 1992.

The aim of the Auger Observatory is to measure the energy, direction, and composition of the highest energy (> 1019 eV) cosmic rays. No known mechanism can fully account for the acceleration of cosmic rays to such enormous energies - energies orders of magnitude beyond what is or ever will be achieved at terrestrial particle accelerators. Their extreme energy ensures that they suffer modest deflections when passing through relatively weak Galactic or intergalactic magnetic fields. Cosmic rays also may interact with the cosmic background radiation, so any observed at earth must have originated at distances within about 100 Mpc. Few possible sources exist so nearby.

The near-linearity of trajectories and closeness of their origins make possible point-source astronomy with the highest energy cosmic rays. Accurate reconstruction of the axes of air showers produced in the earth's atmosphere by these cosmic rays should indicate their celestial source(s). The properties of the air showers also give information on particle interactions in a new energy regime.

An overview and description of the Auger Observatory.

A recent summary of scientific results from the Auger Observatory.

Current and Selected Publications

  • Bounds on the density of sources of ultra-high energy cosmic rays from the Pierre Auger Observatory, The Pierre Auger Collaboration, JCAP, 05 (2013) 009; arXiv:1304.1576

  • Ultra-High Energy Neutrinos at the Pierre Auger Observatory, The Pierre Auger Collaboration, Advances in High Energy Physics, 2013 (2013) 708680; arXiv:1304.1630

  • 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); arXiv:1208.1520

  • A Heitler model of extensive air showers, J. Matthews, Astropart. Phys. 22 (2005) 387.

  • Observation of a Neutrino Burst in Coincidence with Supernova 1987A in the Large Magellanic Cloud, (R.M. Bionta et al.), Phys. Rev. Lett. 58 (1987) 1494.