D. K. Koul

Publications (5)6.84 Total impact

• Source

  Available from: arxiv.org

  Article: Factorial moment studies of Cherenkov images

  A. Razdan, D. K. Koul, M. K. Koul, S. K. Charagi
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  ABSTRACT: In this paper we study factorial moments of simulated Cherenkov images of TACTIC type gamma ray telescope for cosmic gamma rays and proton segregation. A comprative and supplemnetary studies between factorial moments and Hillas parameters using ANN is discussed.
  10/2005;
• Source

  Available from: articles.adsabs.harvard.edu

  Article: Spot size of 17m-diameter MACE reflector in presence of surface inaccuracies

  D. K. Koul, M. K. Koul, A. K. Tickoo, C. L. Bhat
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  ABSTRACT: The MACE (for Major Atmospheric Cerenkov Experiment), an imaging cerenkov telescope for gamma-ray astronomy investigations in the sub-TeV energy bracket, plans to use a 17 m-diameter high quality reflecter mounted with a high definition imaging camera in its focal plane. The spot size of the MACE has been estimated for, both, on-and off-axis cases, considering an ideal mirror surface. The effect on this spot-size due to surface smoothness errors has been investigated.
  Bulletin of the Astronomical Society of India 02/2002; 30:373-376. · 2.72 Impact Factor
• Source

  Available from: articles.adsabs.harvard.edu

  Article: Recent results on crab nebula and Mkn-421 observations with TACTIC imaging element

  N. Bhatt, N. K. Agarwal, C. K. Bhat, S. Bhattacharaya, S. K. Charagi, P. Chandra, N. Chauhan, V. K. Dhar, A. Goyal, H. C. Goyal, [......], M. K. Koul, R. C. Rannot, A. K. Razdan, S. Sahaynathan, M. L. Sapru, N. Satyabhama, A. K. Tickoo, K. Venugopal, K. K. Yadav, C. L. Bhat
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  ABSTRACT: The results of our recent observational campaigns on the Crab Nebula and Mkn-421, carried out with the 349-pixel Imaging Element of the TACTIC array, are presented alongwith the details of the data analysis. Analysis of the recorded events reveals presence of significant signals from both these sources.
  Bulletin of the Astronomical Society of India 02/2002; 30:385-388. · 2.72 Impact Factor
• Source

  Available from: Autar Tickoo

  Article: Observations of the Crab Nebula, Mkn 501 and Mkn 421 using the TACTIC Imaging Element

  N. Bhatt, N. K. Agarwal, C. K. Bhat, S. Bhattacharyya, V. K. Dhar, A. Goyal, H. C. Goyal, C. L. Kaul, D. K. Koul, I. K. Kaul, [......], M. Kothari, R. C. Rannot, A. K. Razdan, S. Sahayanathan, M. L. Sapru, N. Satyabhama, A. K. Tickoo, N. Venugopal, K. K. Yadav, C. L. Bhat
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  ABSTRACT: The results of our observational campaigns on the two extragalactic sources Mkn 501 and Mkn 421, carried out with the Imaging Element of the TACTIC array, during March-May, 1998 and April-May, 1999, are presented. The results indicate that the two BL Lac objects (Mkn 501 and Mkn 421) were in a `low' gamma-ray emission state during both epochs of our observations.
  07/1999;
• Article: Energy-dispersive X-ray fluorescence spectrometry technique as an efficient monitoring tool for mercury contamination

  C. K. Bhat, C. L. Bhat, G. S. Lodha, D. K. Koul
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  ABSTRACT: This paper illustrates the useful early-warning role of the energy-dispersive X-ray fluorescence technique against a potential health hazard being posed by dumping effluents from an industrial unit involved in the manufacture of lead-batteries, in a nearby water-canal used for irrigation purposes by surrounding villages. These effluents were shown to contain mercury at a potentially unsafe level, resulting in timely initiation of necessary preventive measures. The standard fundamental parameter method was invoked for a quantitative estimation of the mercury (Hg) concentration. In addition, L-series (rather than the usual K-series) X-rays were used for excitation, mainly on account of the type of the available excitation source.
  Environmental Monitoring and Assessment 04/1996; 41(1):77-86. · 1.40 Impact Factor