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  • Planetary nebulae 
    Mallik, D. C. V (Astronomical Society of India, 1982-06)
    Recent research on planetary nebulae is reviewed, with special emphasis on ultraviolet and infrared observations. Various distance scales and statistics based on them are discussed and the emperical mass-radius relation ...
  • Planetary nebulae - Origin and evolution 
    Mallik, D. C. V (Astronomical Society of Australia, 1991)
    The review describes some of the progress made in observations and their interpretation, particularly in the context of the evolution of the nebulae and the central stars. It includes a discussion on the improved determinations ...
  • Planetary nebulae and nitrogen enrichment in the galaxy 
    Mallik, D. C. V (Geneva Observatory, 1978)
    The extent of nitrogen enrichment of the interstellar gas by planetary-nebula formation is evaluated, and the nitrogen and oxygen abundance gradients in the disk of the Galaxy are derived on the basis of a simple model for ...
  • Planetary nebulae with UVIT II. Revelations from far-UV vision of Butterfly nebula NGC 6302 
    Kameswara Rao, N; De Marco, O; Sriram, K; Murthy, J; Ray, A; Sutaria, F. K; Mohan, Rekhesh (EDP Sciences, 2018-12)
    The high excitation planetary nebula, NGC 6302, has been imaged in two far-ultraviolet (FUV) filters, F169M (Sapphire; λeff: 1608 Å)and F172M (Silica; λeff: 1717 Å) and two near-UV (NUV) filters, N219M (B15; λeff: 2196 Å) ...
  • Planetary nebulae with UVIT: A progress report 
    Kameswara Rao, N; Sutaria, F; Murthy, J; Ray, A; Pandey, G (Indian Academy of Sciences, 2021-10)
    The spectral region between 1250–3000 A contains important spectral lines to understand the ˚ morphological structures and evolution of planetary nebulae. This is the region sampled by UVIT through various filter bands ...
  • Planetary nebulae with UVIT: Far ultra-violet halo around the Bow Tie nebula (NGC 40) 
    Kameswara Rao, N; Sutaria, F. K; Murthy, J; Sriram, K; Mohan, Rekhesh; Ray, A (EDP Sciences, 2018-01)
    Context. NGC 40 is a planetary nebula with diffuse X-ray emission, suggesting an interaction of the high-speed wind from WC8 cen- tral star (CS) with the nebula. It shows strong C IV 1550 Å emission that cannot be ...
  • Planets in the early Universe 
    Shchekinov, Y. A; Safonova, M; Murthy, J (Springer, 2013-07)
    Several planets have recently been discovered around stars that are old and metal-poor, implying that these planets are also old, formed in the early Universe together with their hosts. The canonical theory suggests that ...
  • Plaque unveiled on 200 years of IIA 
    Indian Express (Indian Express, 1987-01-07)
  • Plasma acceleration by ion-acoustic turbulence 
    Krishan, V (Kluwer Academic Publishers, 1980-12)
    An energetic proton beam passing through a stationary ionized medium, excites ion-acoustic turbulence. The ion-acoustic instability saturates due to the non-linear indirect wave-particle scattering. The electric field ...
  • Plasma acceleration by ion-acoustic turbulence 
    Krishan, V (D. Reidel Publishing Co., 1980-12)
    An energetic proton beam passing through a stationary ionized medium, excites ion-acoustic turbulence. The ion-acoustic instability saturates due to the non-linear indirect wave-particle scattering. The electric field ...
  • Plasma condensation in coronal loops 
    O'Shea, E; Banerjee, D; Doyle, D. J (EDP Sciences, 2007-11)
    Aims.Using temporal series data from the Coronal Diagnostic Spectrometer (CDS) on SOHO, we seek to investigate plasma condensation through the use of spectroscopic analysis. Methods.Using a space-time (X-T) type plot we ...
  • Plasma damping of gravitational waves 
    Sivaram, C (International Astronomical Union, 1990)
  • Plasma diagnostics for SUMER on board the SOHO mission 
    Dwivedi, B. N (Astronomical Society of India, 1996)
    We highlight a rich source of high-resolution EUV observations that the Solar Ultraviolet Measurements of Emitted Radiation (SUMER) instrument, on board the SOHO mission, is capable of making in the broad spectral range ...
  • Plasma heating in a sheared magnetic field 
    Krishan, V (Indian Academy of Sciences, 1981-12)
    The mechanism of spatial resonance of Alfven waves for heating a collisionless plasma is studied in the presence of a twisted magnetic field. In addition to modifying the equilibrium condition for a cylindrical plasma, the ...
  • Plasma mechanisms for variability in active galactic nuclei 
    Krishan, V; Wiita, P J (1994-03)
    We consider several physical processes, dominated by plasma effects, that might play roles in producing variability in Active Galactic Nuclei (AGN). One class of processes involves oscillations in the plasma itself. If ...
  • Plasma wave aided two photon decay of an electromagnetic wave in a plasma 
    Magesh Kumar, K. K; Singh, R; Krishan, V (American Institute of Physics Publishing, 2014-11)
    The presence of a Langmuir wave in an unmagnetized plasma is shown to allow parametric decay of an electromagnetic wave into two electromagnetic waves, which is otherwise not allowed due to wave number mismatch. The decay ...
  • Plasmas: the first state of matter 
    Krishan, V (Cambridge University Press, 2014)
    Most astronomers believe that the universe began about 15 billion years ago when an explosion led to its expansion and cooling. The present state of the universe compels us to believe that the universe was extremely hot ...
  • Plume-like structures of extinction clouds at 19 Saturn radii 
    Vasundhara, R; Bhattacharyya, J. C; Rozario, M (Astronomical Society of India, 1986-12)
    Observations of the occultation of the star SAO 158763 by Saturn's magnetospheric region around 19 Saturn radii on May 12, 1984 are compared with the observations by Mahra et al. (1985) of the same event. Certain disparities ...
  • Pluto's Atmosphere in Plateau Phase Since 2015 from a Stellar Occultation at Devasthal 
    Sicardy, Bruno; Nagarhalli M, Ashok; Tej, Anandmayee; Pawar, Ganesh; Deshmukh, Shishir; Deshpande, Ameya; Sharma, Saurabh; Desmars, Josselin; Assafin, Marcelo; Ortiz, Jose Luis; Benedetti-Rossi, Gustavo; Braga-Ribas, Felipe; Vieira-Martins, Roberto; Santos-Sanz, Pablo; Chand, Krishan; Bhatt, B. C (IOP Publishing, 2021-12-20)
    A stellar occultation by Pluto was observed on 2020 June 6 with the 1.3 m and 3.6 m telescopes located at Devasthal, Nainital, India, using imaging systems in the I and H bands, respectively. From this event, we derive ...
  • PM asks Indian Scientists' to return home 
    Deccan Herald (Deccan Herald, 1986-01-07)

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