All-sky survey high resolution air-shower detector (Ashra)

Yoichi Asaoka*

*Corresponding author for this work

Research output: Contribution to journalConference articlepeer-review


We propose a new air fluorescence and Cerenkov detector Ashra. The Ashra phase-1 detector consists of 1+1/3 observational stations installed at the distance of 30-40 km in a mountain site. It ensures the large target mass for neutrinos and low-energy threshold for TeV gamma rays. The observational station is composed of 12 wide-angle high-precision telescope, which can cover completely all-sky view. Each telescope has a field-of-view of 50 deg. × 50 deg. and spot size resolution of 1 arcmin. To realize the Ashra telescope concept, we newly apply the following techniques matured in the other fields: i) Baker-Nunn optics optimized to keep better than 1 arcmin resolution in 50 deg. field of view, ii) electrostatic lens image intensifier tube with the resolution matched with that of the above optics, iii) photoelectric image pipeline with self triggering capability using light splitting after sufficient amplification, and iv) CMOS image sensor which read triggered images out of the above IIT. These novel techniques allow us an excellent opportunity for simultaneous observation of air fluorescence and Cerenkov lights with 1 arcmin resolution in entirely all sky. This will open a new field, "Observational Particle Astrophysics" by continuously observing TeV gamma-rays, VHE-neutrinos, Knee-CRs, and UHECRs.

Original languageEnglish
Article numberN8-5
Pages (from-to)144-146
Number of pages3
JournalIEEE Nuclear Science Symposium Conference Record
Publication statusPublished - 2003 Dec 1
Externally publishedYes
Event2003 IEEE Nuclear Science Symposium Conference Record - Nuclear Science Symposium, Medical Imaging Conference - Portland, OR, United States
Duration: 2003 Oct 192003 Oct 25


  • Air shower phenomena
  • CMOS image sensor
  • Image intensifier tube
  • Very high-energy neutrinos

ASJC Scopus subject areas

  • Radiation
  • Nuclear and High Energy Physics
  • Radiology Nuclear Medicine and imaging


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