IIA Institutional Repository

Browsing IIAP Publications by Title

Browsing IIAP Publications by Title

Sort by: Order: Results:

  • Center-to-limb Observations and Modeling of the Ca I 4227 Å Line 
    Supriya, H. D; Smitha, H. N; Nagendra, K. N; Stenflo, J. O; Bianda, M; Ramelli, R; Ravindra, B; Anusha, L. S (IOP Publishing, 2014-09-20)
    The observed center-to-limb variation (CLV) of the scattering polarization in different lines of the Second Solar Spectrum can be used to constrain the height variation of various atmospheric parameters, in particular the ...
  • A central gravitational redshift model for the absorption redshift systems in quasi-stellar objects 
    Das, P. K (Royal Astronomical Society, 1979-01)
    Static, spherically symmetric configurations of core and envelope type have been considered in General Relativity as central gravitational redshift models for the quasi-stellar objects (QSOs) and an attempt has been made ...
  • The central region of the enigmatic Malin 1 
    Saha, Kanak; Dhiwar, Suraj; Barway, Sudhanshu; Narayan, Chaitra; Tandon, Shyam (Indian Academy of Sciences, 2021-10)
    Malin 1, being a class of giant low surface galaxies, continues to surprise us even today. The HST/F814W observation has shown that the central region of Malin 1 is more like a normal SB0/a galaxy, while the rest of the ...
  • Central regions of Sersic-Pastoriza galaxies - A photographic study 
    Prabhu, T. P (Indian Academy of Sciences, 1980-12)
    A classification scheme is proposed for the central regions of Sérsic-Pastoriza galaxies based on high resolution photographs of 50 objects in the integrated light (4000 Å-8700 Å). Structures of two different linear scales ...
  • The Central Velocity Field in NGC 253: Possible Indication of a Bar 
    Das, M; Anantharamaiah, K. R; Yun, M. S (The American Astronomical Society, 2001-03)
    We have investigated whether motion of gas in a barlike potential can account for the peculiar but systematic velocity field observed in the nuclear region of the starburst galaxy NGC 253. This unusual velocity field with ...
  • Centre-limb variation of solar excitation temperature as derived from Ti I lines 
    Sankaranarayanan, S (Government Observatory, Madras, 1957-12)
  • Centrifugal Acceleration in Pulsar Magnetospheres 
    Thomas, R. M. C; Gangadhara, R. T (International Astronomical Union, 2004)
    We present a relativistic model of pulsar radio emission by plasma accelerated along the rotating magnetic field lines projected on to a 2D plane perpendicular to the rotation axis. We have derived the expression for the ...
  • Centrifugal acceleration of plasma in pulsar magnetosphere 
    Gangadhara, R. T; Krishan, V (Indian Academy of Sciences, 2003-12)
    We present a relativistic model for the centrifugal acceleration of plasma bunches and the coherent radio emission in pulsar magnetosphere. We find that rotation broadens the width of leading component compared to the width ...
  • Centroid detection by Gaussian pattern matching in adaptive optics 
    Vyas, A; Roopashree, M. B; Prasad, B. R (Foundation of Computer Science, 2010)
    Shack Hartmann wavefront sensor is a two dimensional array of lenslets which is used to detect the incoming phase distorted wavefront through local tilt measurements made by recording the spot pattern near the focal plane. ...
  • Century long study of sunspot activity using the Kodaikanal white-light data 
    Amareswari, K; Sankarasubramanian, K; Ravindra, B (Cambridge University Press, 2018-02)
    Sunspots are the most obvious and high contrast observable feature of solar magnetic activity in the photosphere. The morphological and kinematic behaviour of sunspots on the solar surface need to be studied over a long ...
  • A century of solar Ca ii measurements and their implication for solar UV driving of climate 
    Foukal, P; Bertello, L; Livingston, W. C; Pevtsov, A. A; Singh, J; Tlatov, A. G; Ulrich, R. K (Springer, 2009-04)
    Spectroheliograms and disk-integrated flux monitoring in the strong resonance line of Ca ii (K line) provide the longest record of chromospheric magnetic plages. We compare recent reductions of the Ca ii K spectroheliograms ...
  • Cerenkov radiation emitted by charged particles in a gravitational field 
    Gupta, A; Mohanty, S; Samal, M. K (Institute of Physics, 1999-01)
    Charged particles propagating in an external gravitational field with negative Ricci tensor components can emit radiation by the Cerenkov process. The external gravitational field acts like an effective refractive index ...
  • The CH fraction of carbon stars at high galactic latitudes 
    Goswami, A; Drisya, K; Shantikumar, N. S (Blackwell Publishing, 2010-02)
    CH stars form a distinct class of objects with characteristic properties like iron deficiency, enrichment of carbon and overabundance of heavy elements. These properties can provide strong observational constraints for the ...
  • CH stars at high Galactic latitudes 
    Goswami, A (Blackwell Publishing, 2005-05)
    Carbon-rich stars of Population II, such as CH stars, can provide direct information on the role of low- to intermediate-mass stars of the halo in early Galactic evolution. Thus accurate knowledge of the CH stellar population ...
  • Champagne flow and triggered star formation in NGC 1893 
    Maheswar, G; Sharma, S; Biman, J. M; Pandey, A. K; Bhatt, H. C (Blackwell Synergy, 2007-08)
    Using Hα grism spectroscopy and optical and Two-Micron All-Sky Survey photometry of the fields containing NGC 1893 and two emission nebulae, Sim 129 and Sim 130, we show the presence of a number of Hα and near-infrared ...
  • Chandra–Eddington episode 
    Sivaram, C (Indian Academy of Sciences, 2006-01)
  • Change of rotation rates of sunspot groups during their lifetimes: Clues to the sites of origin of different flux tubes 
    Hiremath, K. M (E D P Sciences, 2002-05)
    From 103 years of data of non-recurrent sunspot groups and for the two sets (area <100 millionths of hemisphere and >100 millionths of hemisphere), irrespective of their life span, we compute rotation rates and rate of ...
  • Changes in Photospheric Lorentz Force in Eruptive and Confined Solar Flares 
    Maity, Samriddhi Sankar; Sarkar, Ranadeep; Chatterjee, Piyali; Srivastava, Nandita (American Astronomical Society, 2024-02-10)
    Solar flares are known to leave imprints on the magnetic field in the photosphere, often manifested as an abrupt and permanent change in the downward-directed Lorentz force in localized areas inside the active region. Our ...
  • Changes of atmospheric electric potential gradient at Poona during disturbed weather 
    Sivaramakrishnan, M. V (The Manager Government of India Press, Simla, 1953-01)
    A detailed study of the changes of atmospheric potential gradient during disturbed weather at Poona for 5 years 1936-40 has been made. From the analysis it is seen that if during rainfall the potential gradient is negative ...
  • The changing interstellar medium of massive elliptical galaxies and cosmic evolution of radio galaxies and quasars 
    Mangalam, A; Gopal-Krishna; Wiita, Paul J (Blackwell Publishing, 2009-06-03)
    The recently discovered apparent dramatic expansion in the effective radii of massive elliptical galaxies from z≃ 2 to ≃0.1 has been interpreted in terms of either galaxy mergers or the rapid loss of cold gas due to ...

Search DSpace


Browse

My Account