A search for ultra-high energy neutron point sources with the Auger surface detector

Open Access
Cheng, Shih-ho
Graduate Program:
Doctor of Philosophy
Document Type:
Date of Defense:
May 23, 2013
Committee Members:
  • Paul Sommers, Dissertation Advisor
  • Stephane Coutu, Committee Member
  • Douglas Cowen, Committee Member
  • Eric D Feigelson, Committee Member
  • astro-parcticle physics
  • cosmic rays
  • neutron sources
  • extensive air showers
A thorough blind search for point sources of the entire exposed sky, and a stacked targeted search across ten Galactic stellar object target sets, are conducted with the Pierre Auger surface detector data. Theses two analyses reveal no evidence of statistically significant excess of events in any small solid angle that would be indicative of a flux of EeV neutrons from a discrete source. The search covers from -90◦ to +15◦ in declination for energy ranges of 1-2 EeV , 2-3 EeV , E ≥ 3 EeV , and E ≥ 1 EeV . In addition, the flux upper limits on the neutron flux, for the four energy ranges, are derived for a dense grid of directions covering the entire exposed sky. These results contrain scenarios for the production of Galactic ultra-high energy cosmic rays.