The Telescope Array experiment studies ultra high energy cosmic rays using a hybrid detector. Fluorescence telescopes measure the longitudinal development of the extensive air shower generated when a primary cosmic ray particle interacts with the atmosphere. Meanwhile, scintillator detectors measure the lateral distribution of secondary shower particles that hit the ground. The Middle Drum (MD) fluorescence telescope station consists of 14 telescopes from the High Resolution Fly's Eye (HiRes) experiment, providing a direct link back to the HiRes measurements. Using the scintillator detector data in conjunction with the telescope data improves the geometrical reconstruction of the showers significantly, and hence, provides a more accurate reconstruction of the energy of the primary particle. The Middle Drum hybrid spectrum is presented and compared to that measured by the Middle Drum station in monocular mode. Further, the hybrid data establishes a link between the Middle Drum data and the surface array. A comparison between the Middle Drum hybrid energy spectrum and scintillator Surface Detector (SD) spectrum is also shown.
|Number of pages||18|
|Publication status||Published - 2015 Aug|
Bibliographical noteFunding Information:
The Telescope Array experiment is supported by the Japan Society for the Promotion of Science through Grants-in-Aids for Scientific Research on Specially Promoted Research (21000002) “Extreme Phenomena in the Universe Explored by Highest Energy Cosmic Rays” and for Scientific Research (19104006), and the Inter-University Research Program of the Institute for Cosmic Ray Research; by the U.S. National Science Foundation awards PHY-0307098, PHY-0601915, PHY-0649681, PHY-0703893, PHY-0758342, PHY-0848320, PHY-1069280, and PHY-1069286; by the National Research Foundation of Korea (2007-0093860, R32-10130, 2012R1A1A2008381, 2013004883); by the Russian Academy of Sciences , RFBR Grants 11-02-01528a and 13-02-01311a (INR), IISN project No. 4.4509.10 and Belgian Science Policy under IUAP VII/37 (ULB). The foundations of Dr. Ezekiel R. and Edna Wattis Dumke, Willard L. Eccles and the George S. and Dolores Dore Eccles all helped with generous donations. The State of Utah supported the project through its Economic Development Board, and the University of Utah through the Office of the Vice President for Research. The experimental site became available through the cooperation of the Utah School and Institutional Trust Lands Administration (SITLA), U.S. Bureau of Land Management, and the U.S. Air Force. We also wish to thank the people and the officials of Millard County, Utah for their steadfast and warm support. We gratefully acknowledge the contributions from the technical staffs of our home institutions. An allocation of computer time from the Center for High Performance Computing at the University of Utah is gratefully acknowledged.
© 2015 Elsevier B.V. All rights reserved.
All Science Journal Classification (ASJC) codes
- Astronomy and Astrophysics