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Browsing IIAP Publications by Title

Browsing IIAP Publications by Title

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  • Nature of Tilt Angles of Sunspot Groups During the 22nd Solar Cycle 
    Muneer, S; Singh, J (Springer, 2002-10)
    Daily white-light images from Kodaikanal Observatory have been utilized to study the nature of tilt angles of sunspot groups during the 22nd solar cycle. 2416 spot groups have been measured to find the tilt angle. An average ...
  • The Nature of γ -ray loud Narrow-line Seyfert I Galaxies PKS 1502+036 And PKS 2004-447 
    Paliya, Vaidehi S; Stalin, C. S; Shukla, A; Sahayanathan, S (IOP Publishing, 2013-05-01)
    Variable γ-ray emission has been discovered in five radio-loud narrow-line Seyfert 1 (NLSy1) galaxies by the Large Area Telescope on board the Fermi Gamma-ray Space Telescope. This has clearly demonstrated that these NLSy1 ...
  • NCSTC programme on total solar eclipse 1995 
    Kamble, V. B (Indian Institute of Astrophysics, Bangalore, 1997)
    NCSTC and Vigyan Prasar jointly undertook a country wide programme on S & T popularization built around the total solar eclipse (TSE) of October 24, 1995. The main objective of the program was to polarize astronomy in ...
  • Near Infrared Observations of Sakurai's Object during 1998-99 
    Kamath, U. S; Ashok, N. M (Springer, 2002-03)
    We present new near-infrared observations of Sakurai's Object obtained during 1998-99 when this final helium shell flash object was in the dust condensation phase. The infrared colours have reddened compared to earlier ...
  • A Near Infrared Photometric Study of the Young Orion Nebula Star Cluster NGC 1976 
    Qian, Z. Y; Sagar, R (Royal Astronomical Society, 1994-01)
    We have measured the JHK magnitudes of 47 stars in the region of the extremely young Orion nebula star cluster NGC 1976. These, in combination with the existing near-infrared and optical data, are used to study the ...
  • The Near Infrared Spectra of Wolf Rayet Stars 
    Bappu, M. K. V; Ganesh, K. S; Scaria, K. K (Indian Institute of Astrophysics, Bangalore, 1977)
    The near infrared spectra of three Wolf-Rayet stars of the carbon sequence and five of the nitrogen sequence have been studied. Wavelength identifications and intensity scans are presented to show the emission line ...
  • Near simultaneous BV photometry and Hα spectroscopy of the RS Canum Venaticorum binary DM Ursae Majoris 
    Mohin, S; Raveendran, A. V (European Southern Obseravatory, 1994-06)
    Differential BV photometry of DM UMa obtained over 19 nights and near simultaneous Hα spectroscopy obtained over 7 nights during the 1990-91 observing season are presented. From an analysis of the available data we find ...
  • The near ultraviolet transient surveyor (NUTS): An ultraviolet telescope to observe variable sources 
    Ambily, S; Sarpotda, Mayuresh; Mathew, Joice; Binukumar, G; Sreejith, A. G; Nirmal, K; Murthy, J; Safonova, M; Mohan, Rekhesh; Aggarval, Vinod Kumar; Nagabhushanam, S; Jeeragal, Sachin (Springer, 2022-08)
    Observing the ultraviolet (UV) sky for time-varyiable phenomena is one of the many exciting science goals that can be achieved by a relatively small aperture telescope in space. The Near Ultraviolet Transient Surveyor ...
  • Near UV imager with an MCP-based photon counting detector 
    Ambily, S; Mathew, J; Mayuresh, Sarpotdar; Sreejith, A. G; Nirmal, K; Prakash, A; Safonova, M; Murthy, J (SPIE-The International Society for Optical Engineering, 2016-07)
    We are developing a compact UV Imager using light weight components, that can be own on a small CubeSat or a balloon platform. The system has a lens-based optics that can provide an aberration-free image over a wide field ...
  • Near-infrared and optical imaging of Q2345+007: The largest gravitationally lensed QSO system? 
    Gopal-Krishna; Yates, M; Wiita, P. J; Smette, A; Pati, A. K; Altieri, B (The European Southern Observatory, 1993-12)
    We have taken K, R, V, and B band images of Q 2345+007, which has been claimed to be the gravitationally lensed quasar with the widest separation between the two images (approximately equal 7 arcsec), although the lens ...
  • Near-Infrared and Optical Morphology of the Dusty Galaxy NGC 972 
    Mayya, Y. D; Ravindranath, S; Carrasco, L (The American astronomical Society, 1998-10)
    Near-infrared (NIR) and optical surface photometric analyses of the dusty galaxy NGC 972 are presented. The photometric profiles in the BVRJHK bands can be fitted with a combination of Gaussian and exponential profiles, ...
  • Near-infrared and optical studies of the fast nova V4643 Sgr (Nova Sagittarii 2001) 
    Ashok, N. M; Banerjee, D. P. K; Varricatt, W. P; Kamath, U. S (Blackwell Publishing, 2006-05)
    V4643 Sagittarii or Nova Sagittarii 2001 was discovered in outburst at 7.7 mag on 2001 February 24. Here, we present near-infrared results of this fast classical nova obtained in the early decline phase in 2001 March ...
  • Near-infrared imaging of barred halo-dominated low surface brightness galaxies 
    Honey, M; Mousumi Das; Ninan, J. P; Manoj, P (Oxford University Press on behalf of the Royal Astronomical Society, 2016-10-21)
    We present a near-infrared (NIR) imaging study of barred low surface brightness (LSB) galaxies using the TIFR NIR Spectrometer and Imager. LSB galaxies are dark matter dominated, late-type spirals that have low-luminosity ...
  • A near-infrared photometer for the 1-m telescope of Vainu Bappu Observatory 
    Mishra, Anwesh Kumar; Kamath, U. S (Indian Academy of Sciences, 2021-04)
    A near-infrared photometer based on an InGaAs PIN photodiode and the filter set recommended by Infrared Working Group (IRWG) have been designed and built. It is mounted on the 1-m Carl–Zeiss telescope at the Vainu Bappu ...
  • Near-infrared photometric study of open star cluster IC 1805 
    Sagar, R; Yu, Q. Z (American Astronomical Society, 1990-04)
    The JHK magnitudes of 29 stars in the region of open star cluster IC 1805 were measured. These, and the existing infrared and optical observations, indicate a normal interstellar extinction law in the direction of the ...
  • Near-Infrared Spectra of Some Symbiotic Stars 
    Kamath, U. S; Ashok, N. M (Astronomical Society of the Pacific, 2003)
  • Near-IR Spectroscopy of CEMP Stars with SOAR/OSIRIS 
    Kennedy, C. R; Sivarani, T; Beers, T. C; Rossi, S; Placco, V. M; Johnson, J; Masseron, T (Cambridge University Press, 2010-03)
    We report on medium-resolution near-IR spectroscopy of a sample of over 60 Carbon- Enhanced Metal-Poor (CEMP) stars observed with SOAR/OSIRIS, selected from the HK survey of Beers and colleagues and the Hamburg/ESO Survey ...
  • Near-simultaneous Spectroscopic and Broadband Polarimetric Observations of BE Stars 
    Ghosh, K; Iyengar, K. V. K; Ramsey, B. D; Austin, R. A (The American Astronomical Society, 1999-08)
    Near simultaneous optical spectroscopic (on four nights) and broadband linear continuum (B, V, R,and I bands) polarimetric (on seven nights) observations of 29 Be stars were carried out during 1993November-December. The ...
  • Nearly Century-scale Variation of the Sun’s Radius 
    Hiremath, K. M; Rozelot, J. P; Sarp, V; Kilcik, A; Pavan, D. G; Gurumath, S. R (IOP Publishing, 2020-03-10)
    The Kodaikanal Archive Program (India) is now available to the scientific community in digital form as daily digitized solar white light pictures, from 1923 to 2011. We present here the solar radius data, obtained after a ...
  • Nebula around R Corona Borealis 
    Kameswara Rao, N; Lambert, David L (International Astronomical Union, 2012-08-30)
    The star R Corona Borealis (R CrB) shows forbidden lines of [O II], [N II], and [S II] during the deep minimum when the star is fainter by about 8 to 9 magnitudes from normal brightness, suggesting the presence of nebular ...

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