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  • 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 ...
  • CH and CH/sup+/ Lines in Facula Models 
    Tripathi, B. M (Astronomical Society of India, 1978-09)
    Equivalent width calcultions for CH and CH/sup+/ are carried out in three facula models. For CH, the lamda4313.662 A line of the (0-0) band of the transition /sup2/ Delta - /sup2/II of the Q1c branch, and for CH/sup+/, the ...
  • 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 level population density with time in the solar quiet chromospheric atmosphere 
    Barman, S. K; Kariyappa, R (Astronomical Society of India, 2001)
    Employing a law of weak acoustic wave, the ratio of population density N2/N1 with time for the Ca II H and K lines appropriate for the solar quiet chromosphere have been calculated. This has been done by solving the equations ...
  • 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 ...
  • Changing lives 
    Sivaram, C (Deccan Herald, 2010-06-15)
  • Changing look AGN Mrk 590: broad-line region and black hole mass from photometric reverberation mapping 
    Amit Kumar Mandal; Schramm, Malte; Rakshit, Suvendu; Stalin, C. S; Vijarnwannaluk, Bovornpratch; Rujopakarn, Wiphu; Poshyachinda, Saran; Kouprianov, Vladimir V; Haislip, Joshua B; Reichar, Daniel E; Sagar, R; Mathew, Blesson (Oxford University Press on behalf of Royal Astronomical Society, 2021-12)
    We present the results of photometric reverberation mapping observations on the changing look active galactic nucleus Mrk 590 at z = 0.026. The observations were carried out from 2018 July to December using broad-band B-, ...
  • Changing molecular gas properties in the bar and center of NGC 7479 
    Hüttemeister, S; Aalto, S; Das, M; Wall, W. F (European Southern Observatory, 2000-11)
    We present sensitive interferometric 12/supCO, 13/supCO and HCN observations of the barred spiral galaxy NGC 7479, one of the few barred galaxies known to have a continuous gas-filled bar. We focus on the investigation and ...
  • Chaos and Regularity in Adaptive Lattice Dynamics 
    Sinha, S (World Scientific Publishing Company, 1995-04)
    We describe the rich spectrum of spatio-temporal phenomena emerging from a class of models incorporating adaptive dynamics on a lattice of nonlinear (typically chaotic) elements. The investigation is based on extensive ...
  • Characteristics of damping of the pulses in the sun 
    Das, G. C (D.Reidel Publishing Co.,, 1981-06)
    Mathematical modelling is used in determining the rotational frequency and the density of an ionized medium. It is noted that the technique derives from the measurement of the group travel time for a wave propagating in a ...
  • Characteristics of night sporadic-E at Kodaikanal 
    Sastri, J. H; Murthy, B. S (National Institute of Science Communication And Information Resources, 1975-09)
    Published ionospheric data were used as a basis to study the characteristics of nighttime Es (blanketing frequency, virtual height, and transparency range) at Kodaikanal (geomag. lat.: 0.6 N; dip: 3.5 N) with the object ...
  • Characteristics of Polar Coronal Hole Jets 
    Chandrashekhar, K; Bemporad, A; Banerjee, D; Gupta, G. R; Teriaca, L (EDP Sciences, 2014-01)
    Context. High spatial- and temporal-resolution images of coronal hole regions show a dynamical environment where mass flows and jets are frequently observed. These jets are believed to be important for the coronal heating ...

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