IIA Institutional Repository

Browsing by Author "Chitnis, V. R"

Browsing by Author "Chitnis, V. R"

Sort by: Order: Results:

  • Long-term study of Mkn 421 with the HAGAR array of telescopes 
    Sinha, A; Shukla, A; Saha, L; Acharya, B. S; Anupama, G. C; Bhattacharjee, P; Britto, R. J; Chitnis, V. R; Prabhu, T. P; Singh, B. B; Vishwanath, P. R (EDP Sciences, 2016-07)
    Context. The HAGAR Telescope Array at Hanle, Ladakh has been regularly monitoring the nearby blazar Mkn 421 for the past seven years. Aims. Blazars show flux variability in all timescales across the electromagnetic ...
  • Longitudinal shower development and its signature at observation level 
    Chitnis, V. R; Bhat, P. N (Astronomical Society of India, 2002)
    From a study of Cverenkov photon arrival times at various core distances at the observation level it has already been established that the photon front is well fitted with a spherical surface traveling at the speed of light ...
  • A mini ACT experiment at low and high altitudes 
    Vishwanath, P. R; Acharya, B. S; Bhat, P. N; Chitnis, V. R (Tata Institute of Fundamental Research, 2005)
    A simple experimental apparatus was used to measure rate of cosmic ray events due to Atmospheric Cerenkov Radiation at two mountain altitude sites with the height difference of 3.5 km. The event rates at Hanle (altitude ...
  • Multi-frequency, multi-epoch study of MrK 501: hints for a two-component nature of the emission 
    Shukla, A; Chitnis, V. R; Singh, B. B; Acharya, B. S; Anupama, G. C; Bhattacharjee, P; Britto, R. J; Mannheim, K; Prabhu, T. P; Saha, L; Vishwanath, P. R (IOP Publishing, 2015-01-01)
    Since the detection of very high energy (VHE) γ -rays from Mrk 501, its broadband emission of radiation was mostly and quite effectively modeled using the one zone emission scenario. However, broadband spectral and flux ...
  • Multiwavelength study of the TeV blazar Mrk 421 during a giant flare 
    Shukla, A; Chitnis, V. R; Vishwanath, P. R; Acharya, B. S; Anupama, G. C; Bhattacharjee, P; Britto, R. J; Prabhu, T. P; Saha, L; Singh, B. B (EDP Sciences, 2012-05)
    Aims. The nearby (z = 0.031) TeV blazar Mrk 421 was reported to be in a high state of flux activity since November, 2009. We aim to investigate possible changes in the physical parameters of Mrk 421 during its high state ...
  • Observations of AGNs using PACT 
    Bose, D; Chitnis, V. R; Vishwanath, P. R; Majumdar, P; Rahman, M. A; Singh, B. B; Gupta, A. C; Acharya, B. S (Springer Netherlands, 2007-06)
    We report our observations on 4 AGNs viz, Mkn 421, Mkn 501, 1ES1426+428 and ON231 belonging to a sub-class called blazars. The observations were carried out using the Pachmarhi Array of Cherenkov Telescopes and span about ...
  • Observations with the High Altitude GAmma Ray (HAGAR) telescope array in the Indian Himalayas 
    Britto, R. J; Acharya, B. S; Anupama, G. C; Bhatt, N; Bhattacharjee, P; Bhattacharya, S. S; Chitnis, V. R; Cowsik, R; Dorji, N; Duhan, S. K; Gothe, K. S; Kamath, P. U; Koul, R; Mahesh, P. K; Mitra, A; Nagesh, B. K; Parmar, N. K; Prabhu, T. P; Rannot, R. C; Rao, S. K; Saha, L; Saleem, F; Saxena, A. K; Sharma, S. K; Shukla, A; Singh, B. B; Srinivasan, R; Srinivasulu, G; Sudersanan, P. V; Tickoo, A. K; Tsewang, D; Upadhya, S; Vishwanath, P. R; Yadav, K. K (French Society of Astronomy and Astrophysics, 2010-12)
    For several decades, it was thought that astrophysical sources emit high energy photons within the energy range of the gamma-ray region of the lectromagnetic spectrum also. These photons originate from interactions of high ...
  • Observations with the High Altitude GAmma-Ray (HAGAR) telescope array in the Indian Himalayas 
    Britto, R. J; Acharya, B. S; Anupama, G. C; Bhatt, N; Bhattacharjee, P; Bhattacharya, S; Chitnis, V. R; Cowsik, R; Dorji, N; Duhan, S. K; Gothe, K. S; Kamath, P. U; Koul, R; Manoharan, J; Mahesh, P. K; Mitra, A; Nagesh, B. K; Parmar, N. K; Prabhu, T. P; Rannot, R. C; Rao, S. K; Saha, L; Saleem, F; Saxena, A. K; Sharma, S. K; Shukla, A; Singh, B. B; Srinivasan, R; Srinivasulu, G; Sudersanan, P. V; Tickoo, A. K; Tsewang, D; Upadhya, S. S; Vishwanath, P. R; Yadav, K. K (Copernicus Publications, 2011-11)
    The High Altitude GAmma-Ray (HAGAR) array is a wavefront sampling array of 7 telescopes, set-up at Hanle, at 4270 m amsl, in the Ladakh region of the Himalayas (Northern India). It constitutes the first phase of the HImalayan ...
  • On the Spectral Curvature of VHE Blazar 1ES 1011 + 496: Effect of Spatial Particle Diffusion 
    Sinha, A; Sahayanathan, S; Acharya, B. S; Anupama, G. C; Chitnis, V. R; Singh, B. B (IOP Publishing, 2017-02-10)
    The American Astronomical Society, find out more The Institute of Physics, find out more On the Spectral Curvature of VHE Blazar 1ES 1011+496: Effect of Spatial Particle Diffusion Atreyee Sinha1, S. ...
  • Pachmarhi array of Cerenkov telescopes 
    Bhat, P. N; Acharya, B. S; Chitnis, V. R; D'Souza, A. I; Francis, P. J; Gothe, K. S; John, A. V; Mazumdar, P; Nagesh, B. K; Purohit, P. N; Rahman, M. A; Rao, S. K; Rao, K. K; Sharma, S. K; Stanislaus, A. J; Sudershanan, P. V; Swamy, M. R. K; Upadhyaya, S. S; Murty, B. L. V (Astronomical Society of India, 2000)
    Pachmarhi Array of Cerenkov Telescopes (PACT) consisting of 25 telescopes has been installed at Pachmarhi (longitude : 76d 26' E, latitude : 22d 28' N and altitude : 1075m) recently. The telescopes are deployed in the form ...
  • PACT results on very high energy g-ray emission from CRAB pulsar 
    Sripathi Acharya, B; Vishwanath, P. R; Bhat, P. N; Chitnis, V. R; Majumdar, P; Rahman, M. A; Singh, B. B (International Union of Pure and Applied Physics, 2003-07)
    The data taken on the Crab pulsar by the recently commissioned array of ˇ Cerenkov telescopes at Pachmarhi using the wave front sampling technique have been analyzed. The phasograms show significant excess of events at the ...
  • Performance studies of the PACT experiment 
    Vishwanath, P. R; Acharya, B. S; Bhat, P. N; Chitnis, V. R; Majumdar, P; Rahman, M. A; Singh, B. B (Astronomical Society of India, 2002)
    Monte Carlo calculations have been done to understand various characteristics like the energy threshold, collection area etc of the recently commissioned PACT. The energy threshold of the array for gamma rays is found to ...
  • Pointing of HAGAR telescope mirrors 
    Gothe, K. S; Prabhu, T. P; Vishwanath, P. R; Acharya, B. S; Srinivasan, R; Chitnis, V. R; Kamath, P. U; Srinivasulu, G; Saleem, F; Kemkar, P. M. M; Mahesh, P. K; Gabriel, F; Manoharan, J; Dorji, N; Dorjai, T; Angchuk, D; D'souza, A. I; Duhan, S. K; Nagesh, B. K; Rao, S. K; Sharma, S. K; Singh, B. B; Sudersanan, P. V; Thsering, M. T; Upadhya, S. S; Anupama, G. C; Britto, R. J; Cowsik, R; Saha, L; Shukla, A (Springer, 2013-04)
    An array of seven atmospheric Cherenkov telescopes was commissioned at a high altitude site in Hanle in the Ladakh region of the Himalayas. The array called HAGAR has been designed to observe celestial γ-rays of energy ...
  • A possible high altitude high energy gamma ray observatory in India 
    Cowsik, R; Bhat, P. N; Chitnis, V. R; Acharya, B. S; Vishwanath, P. R (Copernicus Gesellschaft, 2001-08)
    Recently an Indian Astronomical Observatory has been set up at Hanle (32° 46 4 6 N , 78° 57 5 1 E , 4515m amsl) situated in the high altitude cold desert in the Himalayas. The Observatory has 2-m aperture optical-infrared ...
  • Preliminary results on the flux of TeV g-rays from crab system obtained with the PACT at Pachmarhi 
    Sripathi Acharya, B; Bhat, P. N; Chitnis, V. R; Majumdar, P; Rahman, M. A; Singh, B. B; Vishwanath, P. R (International Union of Pure and Applied Physics, 2003-07)
    We have observed the Crab system (Nebula and Pulsar) and the corresponding background regions during many clear nights in the years 1999-2002 ˇ using the atmospheric Cerenkov array at Pachmarhi, PACT. Preliminary results ...
  • Search for TeV gamma-rays from Geminga pulsar 
    Singh, B. B; Chitnis, V. R; Bose, D; Rahman, M. A; Upadhya, S. S; Gothe, K. S; Nagesh, B. K; Purohit, P. N; Rao, S. K; Rao, K. K; Sharma, S. K; Sudersan, P. V; Venkateshmurthy, B. L; Vishwanath, P. R; Acharya, B. S (Elsevier, 2009-09)
    We present the results of observation of the Geminga pulsar carried out in the TeV energy band during the 6 year period spanning 2000–2006 using the Pachmarhi Array of Cherenkov Telescopes (PACT). A long stretch of data, ...
  • Short-timescale γ -Ray Variability in CTA 102 
    Shukla, A; Mannheim, K; Patel, S. R; Roy, J; Chitnis, V. R; Dorner, D; Rao, A. R; Anupama, G. C; Wendel, C (IOP Publishing, 2018-02)
    The fl at-spectrum radio quasar CTA 102 experienced a prolonged state of enhanced activity across the entire observed electromagnetic spectrum during 2016 – 2017, most pronounced during a major outburst between ...
  • Status of HAGAR, the high altitude gamma ray observatory at Hanle 
    Chitnis, V. R; Acharya, B. S; Bhat, P. N; Cowsik, R; Prabhu, T. P; Srinivasan, R; Srivatsan, R; Vishwanath, P. R (Tata Institute of Fundamental Research, 2005)
    A 7 telescope array is planned to be constructed at Hanle in the Himalayas at an altitude of about 4200m above mean sea level for detecting celestial gamma-rays. The atmospheric Cerenkov light pool created by the ...
  • Status of the Himalayan Gamma-Ray Observatory (HIGRO) and observation with HAGAR at very high energies 
    Britto, R. J; Acharya, B. S; Anupama, G. C; Bhatt, N; Bhattacharjee, P; Bhattacharya, S; Chitnis, V. R; Cowsik, R; Dorji, N; Duhan, S. K; Gothe, K. S; Kamath, P. U; Koul, R; Mahesh, P. K; Manoharan, J; Mitra, A; Nagesh, B. K; Parmar, N. K; Prabhu, T. P; Rannot, R. C; Rao, S. K; Saha, L; Saleem, F; Saxena, A. K; Sharma, S. K; Shukla, A; Singh, B. B; Srinivasan, R; Srinivasulu, G; Sudersanan, P. V; Tickoo, A. K; Tsewang, D; Upadhya, S. S; Vishwanath, P. R; Yadav, K. K (French Society of Astronomy and Astrophysics, 2011-12)
    High Altitude GAmma Ray (HAGAR) telescope array, which is the first stage of HImalayan Gamma Ray Observatory (HIGRO), has been successfully installed at Hanle in Himalayas and has been collecting science data since September, ...
  • A study of the performance parameters of the High Altitude Gamma Ray (HAGAR) telescope system at Ladakh in India 
    Saha, L; Chitnis, V. R; Vishwanath, P. R; Kale, S; Shukla, A; Acharya, B. S; Anupama, G. C; Bhattacharjee, P; Britto, R. J; Prabhu, T. P; Singh, B. B (Elsevier Science B.V., 2013-02)
    We present results of Monte Carlo simulations for the High Altitude Gamma Ray (HAGAR) telescope array which detects very high energy gamma rays from astronomical sources. This telescope array, located at Hanle at an altitude ...

Search DSpace

Browse

My Account