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Very High Energy Gamma Ray Emission from Crab Nebula with the PACT Array

P. R. Vishwanath·B. S. Acharya·P. N. Bhat·V. R. Chitnis·P. Majumdar·M. A. Rahman·B. B. Singh
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Abstract

The Crab nebula has proved to be the nearest to a standard candle in VHE $γ-$ ray astronomy. Results on the gamma ray emission from the nebula at various energies have come in the last decade mostly from imaging telescopes. The aim of the new Pachmarhi Atmospheric Cerenkov Telescope (PACT) array has been to use the temporal and spatial distribution of Cerenkov photons in distinguishing between proton and gamma ray showers. The array, with timing information from 175 mirrors, is ideally suited for precise estimation of the arrival direction. Preliminary results from the recent data taken on Crab has shown a 12$σ$ signal with the flux in good agreement with those of the other experiments.

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P. R. Vishwanath, B. S. Acharya, P. N. Bhat, V. R. Chitnis, P. Majumdar, M. A. Rahman, B. B. Singh. 2001-08-23. Very High Energy Gamma Ray Emission from Crab Nebula with the PACT Array. https://arxiv.org/abs/astro-ph/0108372

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