%0 Journal Article
%T TeV Gamma-ray Observations of Markarian 421 using TACTIC during 2009-10
%A P. Chandra
%A R. C. Rannot
%A K. K. Yadav
%A A. K. Tickoo
%A K. K. Singh
%A K. Chanchalani
%A M. Kothari
%A N. K. Agarwal
%A A. Goyal
%A H. C. Goyal
%A S. Kotwal
%A N. Kumar
%A P. Marandi
%A K. Venugopal
%A C. K. Bhat
%A N. Bhatt
%A S. Bhattacharya
%A C. Borwankar
%A N. Chouhan
%A V. K. Dhar
%A S. R. Kaul
%A S. K. Koul
%A M. K. Koul
%A R. Koul
%A A. K. Mitra
%A S. Sahayanathan
%A M. Sharma
%J Physics
%D 2012
%I arXiv
%R 10.1088/0954-3899/39/4/045201
%X 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 $\Gamma=2.31\pm0.14$.
%U http://arxiv.org/abs/1202.2984v1