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arXiv · 1202.2984

TeV Gamma-ray Observations of Markarian 421 using TACTIC during 2009-10

P. Chandra·R. C. Rannot·K. K. Yadav·A. K. Tickoo·K. K. Singh·K. Chanchalani·M. Kothari·N. K. Agarwal·A. Goyal·H. C. Goyal·S. Kotwal·N. Kumar·P. Marandi·K. Venugopal·C. K. Bhat·N. Bhatt·S. Bhattacharya·C. Borwankar·N. Chouhan·V. K. Dhar·S. R. Kaul·S. K. Koul·M. K. Koul·R. Koul·A. K. Mitra·S. Sahayanathan·M. Sharma
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Abstract

We have observed the blazar Markarian 421 with the TACTIC $\gamma$-ray telescope at Mt. Abu, India, from 22 November 2009 to 16 May 2010 for 265 hours. Detailed analysis of the data so recorded revealed presence of a TeV $\gamma$-ray signal with a statistical significance of 12.12$\sigma$ at $E_{\gamma}\geq$ 1 TeV. We have estimated the time averaged differential energy spectrum of the source in the energy range 1.0 - 16.44 TeV. The spectrum fits well with the power law function of the form ($dF/dE=f_0 E^{-\Gamma}$) with $f_0=(1.39\pm0.239)\times 10^{-11}cm^{-2}s^{-1}TeV^{-1}$ and $\Gamma=2.31\pm0.14$.

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P. Chandra, R. C. Rannot, K. K. Yadav, A. K. Tickoo, K. K. Singh, K. Chanchalani, M. Kothari, N. K. Agarwal, A. Goyal, H. C. Goyal, S. Kotwal, N. Kumar, P. Marandi, K. Venugopal, C. K. Bhat, N. Bhatt, S. Bhattacharya, C. Borwankar, N. Chouhan, V. K. Dhar, S. R. Kaul, S. K. Koul, M. K. Koul, R. Koul, A. K. Mitra, S. Sahayanathan, M. Sharma. 2012-02-14. TeV Gamma-ray Observations of Markarian 421 using TACTIC during 2009-10. https://doi.org/10.1088/0954-3899/39/4/045201

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