IIA Institutional Repository

Browsing IIAP Publications by Title

Browsing IIAP Publications by Title

Sort by: Order: Results:

  • Subramanian, K. R; Sundaram, G. A. S (Astronomical Society of the Pacific, 2005)
    We present here the observations of the equatorial coronal hole made at 109 MHz on February 25, 1999 with the Gauribidanur Radioheliograph. The brightness temperature of this coronal hole is about 1:7£105 K.We compare our ...
  • Singh, V; Shastri, P; Risaliti, G; Athreya, R (Astronomical Society of the Pacific, 2010-10)
    We investigate the low-frequency radio properties and the X-ray spectral properties of a sample of Seyfert galaxies in order to compare the two subtypes of Seyferts and rigorously test the predictions of Seyfert unification.
  • Golap, K; Sastry, Ch. V (Springer, 1994-03)
    The radio brightness of the quiet outer solar corona at a frequency of 35 MHz in the presence of a radial magnetic field is computed. It is found that the brightness temperature of the ordinary radiation increases ...
  • Ramya, S; Kantharia, N. G; Prabhu, T. P (IOP Publishing, 2011-02)
    The multifrequency radio continuum and 21 cm H I observations of five blue compact dwarf (BCD) galaxies, Mrk 104, Mrk 108, Mrk 1039, Mrk 1069, and I Zw 97, using the Giant Meterwave Radio Telescope (GMRT) are presented ...
  • Ramya, S; Kantharia, N. G; Prabhu, T. P (Astronomical Society of the Pacific, 2009-09)
    We present a GMRT radio continuum and H I study of two Blue Compact Dwarf (BCD) galaxies Mrk 1039 and Mrk 0104. GMRT 610 MHz observations of Mrk 1039 show that the emission is coincident with a bright intense star forming ...
  • Krishan, V; Sivaram, C (Springer, 1983-04)
    The equations describing the linear-acceleration mechanism of radiation emission are generalized and applied to type III and IIIb solar radio bursts. A general expression for the power emitted by an electron in a spatially ...
  • Thomas, R. M. C; Gangadhara, R. T (EDP Sciences, 2005-07)
    We present a relativistic model for the motion of charged particles in rotating magnetic field lines projected onto a plane perpendicular to the rotation axis. By making an approximation that the projected field lines are ...
  • Krishan, V (Institute of Physics, 1982-01)
    The excitation of electromagnetic radiation near the harmonics of electron plasma frequency from a helical electron beam travelling parallel to a helical magnetic field through a stationary inhomogeneous plasma is studied. ...
  • Krishan, V (D. Reidel Publishing Co., 1979-06)
    Interaction of a high-intensity and low-frequency electromagnetic beam with a plasma is investigated. The dynamics of plasma particles under this strong electromagnetic field is calculated without using the perturbation ...
  • Roy, Tridib; Gangadhara, R. T. (IOP Publishing, 2019-07)
    Pulsar radio emission is not well understood because of a lack of knowledge about the emission geometry and the plasma process involved. We develop a mechanism for pulsar radio emission that takes into account the ...
  • Sastry, Ch. V (Indian Institute of Astrophysics, Bangalore, 1986)
    The Continuum emission from the Quiet Sun and active regions is the radiation from the solar atmosphere when there is no transient burst activity. At decametric wavelengths this radiation originates in the outer corona. A ...
  • Thejappa, G (Indian Institute of Astrophysics, Bangalore, 1988)
    The slowly drifting solar type II radio bursts are believed to be due to the flare associated shock waves propagating radially outward in the corona. The main observational characteristics of these bursts show that the ...
  • Benz, A. O; Thejappa, G (European Southern Observatory, 1988-08)
    The "backbone" emission of shock initiated coronal (metric) type II solar radio bursts is considered. The source has extremely narrow bandwidth and appears to be stationary in relation to the shock. The increasingly complete ...
  • Subramanian, K. R (Springer, 2010)
    This chapter provides an overview of the radio emission mechanisms in the Solar atmosphere. Incoherent (free - free emission and gyro - emission) and coherent (plasma emission and electron cyclotron maser emission) emission ...
  • Nayana, A. J; Chandra, Poonam; Krishna, Anoop; Anupama, G. C (American Astronomical Society, 2022-08-01)
    We present extensive radio monitoring of a Type IIb supernova (SN IIb), SN 2016gkg during t ∼ 8−1429 days postexplosion at frequencies ν ∼ 0.33−25 GHz. The detailed radio light curves and spectra are broadly consistent with ...
  • Krishan, V; Sinha, K. P; Krishan, S (D.Reidel Publishing Co.,, 1978-01)
    A linear excitation of electromagnetic modes at frequencies ~_ (n+1/2)ωce , in a plasma through which two electron beams are contra-streaming along the magnetic field is investigated. This may be a source of the observed ...
  • Gireesh, G. V. S; Kathiravan, C; Barve, Indrajit V; Ramesh, R (Springer, 2021-08)
    The radio astronomy group in the Indian Institute of Astrophysics (IIA) has been carrying out routine observations of radio emission from the solar corona at low frequencies (≈40 – 440 MHz) at the Gauribidanur observatory, ...
  • Das, A. K; Bhargava, B. N (Nature Publishing Group, 1953-11)
    In 1932, Bartels put forward the hypothesis that moderate geomagnetic storms with gradual commencements were associated with certain active regions on the sun which he called M-regions. Solar and geomagnetic studies in ...
  • Ramesh, R; Sastry, Ch. V (European Southern Observatory, 2000-06)
    We report the first low frequency radio observations of a depletion that occurred in the outer solar corona in the aftermath of the CME event of 1986 June 5, with the large E-W one dimensional grating interferometer at the ...
  • Yadav, N; Ray, A; Chakraborti, S; Stockdale, C; Chandra, P; Smith, R; Roy, R; Dwarkadas, V; Sutaria, F. K; Pooley, D; Kumar, B; Bose, S (Cambridge University Press, 2014-01)
    SN 2012AW is a type-IIP supernova which exploded in M95. In this paper we discuss the radio observations of this supernova and model them to determine the important parameters relevant to the explosion and the evolution ...

Search DSpace


Browse

My Account