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  • Polarimetric detection of exoplanets transiting T and L brown dwarfs 
    Sengupta, S (IOP Publishing, 2016-10)
    While scattering of light by atoms and molecules yields large amounts of polarization at the B-band of both T and L dwarfs, scattering by dust grains in the cloudy atmosphere of L dwarfs gives rise to significant polarization ...
  • Polarimetric observations of comet P/Halley on 19 March 1986 
    Sen, A. K; Joshi, U. C; Deshpande, M. R; Babu, G. S. D; Kulshrestha, A. K (European Southern Observatory, 1988-10)
    Optical linear polarization data are presented for the coma and tail region of comet P/Halley observed on 19 March 1986. Polarization in the continuum has been found to increase with wavelength while the position angle ...
  • Polarimetric observations of hydrogen deficient stars 
    Raveendran, A. V; Kameswara Rao, N; Deshpande, M. R; Joshi, U. C; Kulshrestha, A. K (Reidel Publishing Company, 1986)
    Polarimetric observations of HD 30353, SU Tau, XX Cam, R CrB, UV Cas, BD +13°3224, BD +10°2179 and HD 124448 are presented. The linear polarization of HD 30353 is found to vary appreciably at Hα over a time scale as short ...
  • Polarimetric observations of the RV Tauri star AR Puppis 
    Raveendran, A. V; Kameswara Rao, N (European Southern Observatory, 1988-03)
    UBVRI polarimetry of AR Pup is presented. Large variations are seen both in the amount and direction of polarization. On one occasion, the polarization in U was found to be as high as 14.6 percent. Polarization level ...
  • Polarimetric studies of carbon stars at high galactic latitude 
    Goswami, A; Drisya, K (EDP Sciences, 2013-01)
    Context. Very little is known about the polarimetric properties of CH stars and carbon-enhanced metal-poor (CEMP) stars, although many of these objects have been studied in detail both photometrically and spectroscopically. Aims. ...
  • Polarimetric study of comets from Mt. Abu observatory 
    Joshi, J. C (Astronomical Society of India, 2005-06)
    The sunlight is scattered by the dust grains present in the coma and tail of comets which makes it visible. The scattered sunlight is characteristically polarized with degree of polarization generally depending upon the ...
  • Polarimetric study of the RV Tauri star AC Herculis 
    Raveendran, A. V; Kameswara Rao, N; Anandaram, M. N (Astronomical Society of Indian, 1989-09)
    BVRI polarimetry of AC Her shows that the wavelength dependence of polarization is weak with a marginal increase towards blue and that the position angle is nearly independent of wavelength. It is argued that the interstellar ...
  • Polarimetry of Comet P/Halley - Properties of dust 
    Sen, A. K; Deshpande, M. R; Joshi, U. C; Kameswara Rao, N; Raveendran, A. V (European Southern Observatory, 1991-02)
    Comet P/Halley was observed polarimetrically for seven nights in IHW and other continuum filters, during its pre- and postpreihelion passages. These polarimetric observations have been combined with the observations taken ...
  • Polarimetry of Supernova SN 1987A - A Dust Shell Model 
    Joshi, U. C; Sen, A. K; Deshpande, M. R; Jain, Rekha (Indian Institute of Astrophysics, 1988)
    Polarimetric measurements of SN1987A in BVR bands were made on March 6 and 7. These observations along with the polarimetric data reported by various other authors within first 30 days of explosion have been discussed. ...
  • Polarimetry: from the sun to stars and stellar environments 
    Nagendra, K. N (editor); Bagnulo, S (editor); Centeno, R (editor); Martinez Gonzalez, M. J (editor) (Cambridge University Press, 2015)
    The advances in solar, planetary, and extrasolar science employing polarimetric tools are far-reaching, and the pace of discovery is accelerating rapidly. In the last three decades, the emphasis of solar polarimetry has ...
  • Polarisation in A-type stars with circumstellar shells 
    Bhatt, H. C (European Southern Observatory, 1996-12)
    We present the results of optical linear polarisation measurements of about 30 A-type stars that are known to be either Ae/A shell stars or have shown anomalous emission in the infrared. Compared with the general population ...
  • Polarization : proving ground for methods in radiative transfer 
    Nagendra, K. N; Anusha, L. S; Sampoorna, M (Societa Astronomica Italiana, 2009)
    Polarization of solar lines arises due to illumination of radiating atom by anisotropic (limb darkened/brightened) radiation. Modelling the polarized spectra of the Sun and stars requires solution of the line radiative ...
  • Polarization and electron densities in the solar corona of 1980 February 16 
    Raju, A. K; Abhyankar, K. D (Astronomical Society of Indian, 1986-12)
    Blue and red photographs of the solar corona obtained on February 16, 1980 with the Japal-Rangapur Observatory double polarigraph are analyzed, and calculations for the degree of polarization and the angle of the magnetic ...
  • Polarization and QPOs from jets in black hole systems 
    Mangalam, A (Indian Academy of Sciences, 2018-12)
    The historical observations of polarized jet emission for Blazars are reviewed and previous models are discussed. Motivated by this, a model for polarization of both steady and transient behavior using a helical magnetic ...
  • Polarization Asymmetry in CSS Sources 
    Saikia, D. J; Gupta, N (Astronomical Society of India, 2003)
    We show that the compact steep spectrum sources are more asymmetric in the polarization of the outer lobes compared with the more extended ones. This could be due to interaction of the jets with infalling material, which ...
  • Polarization Changes of Radiation through Stimulated Raman Scattering 
    Gangadhara, R. T; Krishan, V (The American Astronomical Society, 1993-10)
    We study change in the polarization of electromagnetic waves due to the stimulated Raman scattering in a plasma. In this process an electromagnetic wave undergoes coherent scattering off an electron plasma wave. It is found ...
  • Polarization in binaries 
    Barman, S. K; Peraiah, A (Astronomical Society of India, 1991)
    Theoretical models are computed for estimating linear polarization from the extended dusty outer layers of the components of a close binary system whose surfaces are distorted by rotation and mutual tidal effects. ...
  • Polarization line radiative transfer in the atmospheres of magnetic white dwarfs 
    Nagendra, K. N (Akademie verlag GmbH, 1987)
    Some physical mechanisms which can affect the Zeeman line profiles of magnetic white dwarfs are studied. The pure absorption polarization transfer equation is solved including these mechanisms. The broadening of lines in ...
  • Polarization Maps for the Dark Clouds B:227 and L:121 
    Bhatt, H. C; Jain, S. K (European Southern Observatory, 1993-09)
    Optical linear polarization measurements for stars in the regions of the molecular clouds B 227 and L 121 are presented. The magnetic field geometry in the clouds as indicated by the polarization maps is discussed in ...
  • Polarization Measurements of Post-Asymptotic Giant Branch Candidates and Related Stars 
    Parthasarathy, M; Jain, S. K; Sarkar, G (The American Astronomical Society, 2005-05)
    We have obtained UBVRI polarization measurements of 26 post-asymptotic giant branch (post-AGB) candidates and related stars. The extremely metal-poor post-AGB star HR 4049 has been observed several times. In most cases we ...

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