Heuristic Observation with All-sky High Resolution Air-shower detector

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Ashra (All-sky Survey High Resolution Air-shower detector) is a project to build an unconventional optical telescope complex that images very wide field of view, covering 80% of the sky, yet with the angle resolution of a few arcmin, sensitive to the blue to UV light with the use of image intensifier and CMOS technology. The project primarily aims to observe Cherenkov and fluorescence lights from the lateral and longitudinal developments of very-high energy cosmic rays in the atmosphere. It can also be used to monitor optical transients in the wide field of sky.After approval of the land usage at the Mauna Loa site in July 2005, we immediately occupied the site and began development. After finishing the grading work for the area of 2,419m^2 at the Mauna Loa site at the end of July 2005, installation of electrical power lines and transformers was performed until the beginning of September. We started the construction of the detector in October 2005 after receiving materials from Japan. … More Currently, (mid December 2005) a few shelters having motorized rolling doors, acrylic plate windows to maintain air-tightness, and heat-insulating walls and floors have been constructed and positioned on eight construction piers of concrete blocks at the Mauna Loa site. In the shelters, the optical elements of the light collectors have been already installed. The optical performance were checked and adjusted to be optimum with star light images from the pilot observation.In December 2005, we evaluated the night sky background flux on Mauna Loa using the Ashra light collector installed and aligned in a shelter to be consistent with the background in La Palma and Namibia by the HESS group. From the star light observations, our understanding of the light correction efficiency to be accurate within 5% level.The civil engineering construction of light collectors, in shelters at the Mauna Loa site has been completed. We are performing device installation and specific observation in a step-by-step way to enhance the scientific impacts. Less