Browsing by Title

Sort by: Order: Results:

  • A peculiar multiwavelength flare in the blazar 3C 454.3 
    Gupta, A. C; Mangalam, A; Wiita, J. Paul; Kushwaha, P; Gaur, H; Zhang, H; Gu, M. F; Liao, M; Dewangan, G. C; Ho, L. C; Mohan, P; Umeura, M; Sasada, M; Volvach, A. E; Agarwal, A; Aller, M. F; Aller, H. D; Bachev, R; Lahteenmaki, A; Semkov, E; Strigachev, A; Tornikoski, M; Volvach, L. N (Oxford University Press on behalf of the Royal Astronomical Society, 2017-11)
    The blazar 3C 454.3 exhibited a strong flare seen in γ -rays, X-rays and optical/near-infrared bands during 2009 December 3–12. Emission in the V and J bands rose more gradually than did the γ -rays and soft X-rays, ...
  • The peculiar radio-loud narrow line seyfert 1 galaxy 1H 0323+342 
    Paliya, Vaidehi S; Sahayanathan, S; Parker, M. L; Fabian, A. C; Stalin, C. S; Anjum, A; Pandey, S. B (IOP Publishing, 2014-07-10)
    We present a multi-wavelength study of the radio-loud narrow line Seyfert 1 galaxy (NLSy1), 1H 0323+342, detected by Fermi Gamma Ray Space Telescope. Multi-band light curves show many orphan X-ray and optical flares having ...
  • The peculiar solar flare of 1981 May 13 
    Bondal, K. R; Pant, P; Pande, M. C; Ballabh, G. M (Astronomical Society of India, 1982-06)
    Time-phase photographic observations with 0.7 Armstrong passband H-alpha filter and the morphological-cum-temporal behaviour of a large double solar flare which occurred on 1981 May 13 have been described. The two strands, ...
  • The Peculiar Type Ia Supernova 2005hk 
    Stanishev, V; Taubenberger, S; Blanc, G; Anupama, G. C; Benetti, S; Cappellaro, E; Elias-Rosa, N; Féron, C; Goobar, A; Krisciunas, K; Pastorello, A; Sahu, D. K; Salvo, M. E; Schmidt, B. P; Sollerman, J; Thöne, C. C; Turatto, M; Hillebrandt, W (American Institute of Physics, 2007-08)
    We present a preliminary analysis of an extensive set of optical observations of the Type Ia SN 2005hk. We show that the evolution of SN 2005hk closely follows that of the peculiar SN 2002cx. SN 2005hk is more luminous ...
  • The Peculiar Type Ib Supernova 2006jc: A WCO Wolf-Rayet Star Explosion 
    Tominaga, N; Limongi, M; Suzuki, T; Tanaka, M; Nomoto, K; Maeda, K; Chieffi, A; Tornambe, A; Minezaki, T; Yoshii, Y; Sakon, I; Wada, T; Ohyama, Y; Tanabé, T; Kaneda, H; Onaka, T; Nozawa, T; Kozasa, T; Kawabata, K. S; Anupama, G. C; Sahu, D. K; Gurugubelli, U. K; Prabhu, T. P; Deng, J (The American Astronomical Society, 2008-11)
    ISM: Dust, Extinction, Infrared: ISM, Nuclear Reactions, Nucleosynthesis, Abundances, Stars: Supernovae: General, supernovae: individual (SN 2006jc), Stars: Wolf-Rayet We present a theoretical model for Type Ib supernova ...
  • The Peculiar Type Ib Supernova SN 2005bf: Explosion of a Massive He Star with a Thin Hydrogen Envelope? 
    Anupama, G. C; Sahu, D. K; Deng, J; Nomoto, K; Tominaga, N; Tanaka, M; Mazzali, P. A; Prabhu, T. P (University of Chicago Press, 2005-09)
    We present BVRI photometry and optical spectroscopy of SN 2005bf near maximum light. The maximum phase is broad and occurred around 2005 May 7, about 40 days after the shock breakout. SN 2005bf has a peak bolometric magnitude ...
  • Peculiarities in the Horizontal Branch Stars of Globular Cluster NGC 1851: Discovery of a Blue Straggler Companion to an EHB Star 
    Singh, G; Sahu, S; Subramaniam, A; Yadav, R. K. S (IOP Publishing, 2020-12-10)
    We present a study of far-UV (FUV) bright horizontal branch (HB) stars to understand the peculiarities seen in the HB sequence of the globular cluster NGC 1851, using ground- and space-based multiwavelength data. Optical ...
  • Peculiarities in the ionic tail of Comet Ikeya-Seki (1965f) 
    Krishan, V; Sivaraman, K. R (D. Reidel Publishing Co., 1982-04)
    Direct photographs of Comet Ikeya-Seki obtained on four consecutive days from October 29 to November 1, 1965, are used for an analysis of the multiple helical structures in the ionised tail. The formation of these structures ...
  • The pencil code, a modular MPI code for partial differential equations and particles: multipurpose and multiuser-maintained 
    The Pencil Code Collaboration; Brandenburg, Axel; Johansen, Anders; Bourdin, Philippe A; Dobler, Wolfgang; Lyra, Wladimi; Rheinhardt, Matthias; Bingert, Sven; Haugen, Nils Erland L; Mee, Antony; Gent, Frederick; Babkovskaia, Natalia; Yang, Chao-Chin; Heinemann, Tobias; Dintrans, Boris; Mitra, Dhrubaditya; Candelares, Simon; Warnecke, Jörn; Käpylä, Petri J; Li, Xiang-Yu; Krüger, Jonas; Aarnes, Jørgen R; Sarson, Graeme R; Oishi, Jeffrey S; Schober, Jennifer; Schreiber, Andreas; Chatterjee, Piyali; Käpylä, Maarit J; Plasson, Raphaël; Sandin, Christer; Karchniwy, Ewa; Rodrigues, Luiz Felippe S; Hubbard, Alexander; Guerrero, Gustavo; Snodin, Andrew; Losada, Illa R; Pekkilä, Johannes; Qian, Chengeng (2021-02-21)
    The Pencil Code is a highly modular physics-oriented simulation code that can be adapted to a wide range of applications. It is primarily designed to solve partial differential equations (PDEs) of compressible hydrodynamics ...
  • Penetration electric fields at the nightside dip equator associated with the main impulse of the storm sudden commencement of 8 July 1991 
    Sastri, J. H (American Geophysical Union, 2002-12)
    The geomagnetic storm sudden commencement (ssc) of 8 July 1991 was reported [Wilson et al., 2001] to be characterized by a reduction (enhancement) of X component at midlatitudes in the noon (midnight) sector in the 1-hour ...
  • Penetration of polar electric fields to the nightside dip equator at times of geomagnetic sudden commencements 
    Sastri, J. H; Rao, J. V. S. V; Ramesh, K. B (American Geophysical Union, 1993-10-01)
    Measurements of Doppler Velocity, V D of F - region reflections at normal incidence over Kodaikanal (dip 3°N, 77° 28′E) are used to study the nature of perturbations in F - region vertical plasma drift, V z associated with ...
  • Performance analysis of fourier and vector matrix multiply methods for phase reconstruction from slope measurements 
    Roopashree, M. B; Vyas, A; Prasad, B. R (Central Scientific Instruments Organisation (CSIR), 2009-11)
    The accuracy of wavefront reconstruction from discrete slope measurements depends on the sampling geometry, coherence length of the incoming wavefronts, wavefront sensor specifications and the accuracy of the reconstruction ...
  • Performance analysis of free space optical communication in open-atmospheric turbulence conditions with beam wandering compensation control 
    Anthonisamy, Arockia Bazil Raj; Durairaj, Padmavathi; Lancelot, J. P (IET, 2016-06-16)
    Among various atmospheric effects, beam wandering is the main cause for the major power loss in free space optical communication (FSOC) which cannot be resolved without incorporating the beam wandering compensation (BWC) ...
  • Performance Evaluation of Adaptive Optics Systems 
    Sridharan, R; Raja Bayanna, A; Srivastava, N; Kumar, B; Ravindra, B; Gupta, S. K; Jain, N; Ambastha, A; Venkatakrishnan, P (Astronomical Society of India, 2003)
    Adaptive Optics (AO) systems improve the resolution of ground based telescopes and allow for long exposure images. Their performance depends on the seeing conditions at the time of observations. In this paper, we evaluate ...
  • Performance evaluation of high-speed camera system for adaptive optics 
    Chinnappan, V; Saxena, A. K; Sreenivasan, A (Astronomical Society of India, 2002-09)
    Atmospheric turbulence distorts the incoming wavefront from the star light, thus severely limiting the resolution of the groundbased optical telescopes (Fried 1966). Adaptive optics is being implemented in all big ...
  • Performance of 10.5μm quantum well infrared photodetector for astronomical applications 
    Joseph, Celine; Saxena, A. K (Department of Applied Optics and Photonics, University of Calcutta, 2011)
  • Performance of a speckle interferometer 
    Saha, S. K; Jayarajan, A. P; Sudheendra, G; Chandra, A. U (Astronomical Society of India, 1997)
    An interferometer system for use at the 2.34 meter Vainu Bappu Telescope (VBT), situated at Vainu Bappu Observatory (VBO), Kavalur, to obtain speckle-grams of astronomical objects in the visible wavelength, has been ...
  • Performance of centroiding algorithms at low light level conditions in adaptive optics 
    Vyas, A; Roopashree, M. B; Prasad, B. R (The Institute of Electrical and Electronics Engineers, Inc, 2009)
    The performance metrics of different centroiding algorithms at low light level conditions were optimized in the case of a Shack Hartmann Sensor (SHS) for efficient performance of the adaptive optics system. For short ...
  • Performance of the IIA mosaic CCD camera system 
    Naidu, B. N; Srinivasan, R; Mohan, V; Sagar, R (Astronomical Society of India, 2001)
    We evaluate performance of the 4K x 4K mosaic CCD camera system developed at the Indian Institute of Astrophysics using four Thomson CCDs in a buttable configuration. The camera system consists of a mosaic CCD dewar developed ...
  • Performance of the low light level CCD camera for speckle imagmg 
    Saha, S. K; Chinnappan, V (Astronomical Society of India, 2002-09)
    A new generation CCD detector caJ.led low light level OOD (L3CCD) that performs like an intensified CCD without incorporating a micro channel plate (MOP) for light amplification was procured and tested. A series of ...

Search DSpace

Browse

My Account