Nathan Kundtz with Corbin Covault

Event reconstruction analysis of hybrid ground array and fluorescence detector data for the Auger project

The Auger High Energy Astro-physics experiment seeks to detect high energy particles entering the earth’s atmosphere through the detection of a Chrenkov shower.  These events have a cross section with the atmosphere of approximately 1 event * km^-1year^-1 so a very large detector is needed.  The detector being used spans an area the size of Delaware in the desert of Argentina.  Many ground based detector water tanks equipped with photomultiplier tubes are used to create the large detection area.  A secondary fluorescence detector is used to help determine the direction of the shower and improve the accuracy of reconstructions.  The ground based detectors are equipped with a GPS receiver/antenna used to determine the time of each event.  These clocks must be accurate to an estimated 20ns for event reconstructions to be valid.  Using the powerful reconstructions provided through ground-array and fluorescence detector data the event timing of the clocks on each of the GPS receivers used will be tested.  This data will be compared to receiver timing offsets measured in our lab this summer.  The effects of second order changes in the behavior of the GPS clocks on event reconstruction will also be determined.