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Browsing IIAP Publications by Title

Browsing IIAP Publications by Title

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  • An Image Auto Guider System for Kodaikanal Tower Tunnel Telescope 
    Mathur, Harsh; Thulasidharen, K. C; Hemanth, P; Nagaraju, K; Rajalingam, M (World Scientific Publishing, 2023-02)
    The Kodaikanal Tower Tunnel Telescope (KTT) is a three-mirror Coelostat-based Solar telescope. An inherent variable image drift is present in the KTT which is detrimental to observations particularly to slit-based spectroscopic ...
  • Image data acquisition system for large-format CCDs 
    Ananth, A. V; Srinivasan, R; Srinivasulu, G (SPIE, 1994-06)
    This paper describes the operation and performance of an IBM- PC/AT based image data acquisition system for large format CCDs. The system currently under development can handle image data from CCDs with pixel organization ...
  • Image processing facilities at Vainu Bappu observatory 
    Giridhar, S; Bhattacharyya, J. C; Kutty, K. N (Tata Institute of Fundamental Research, 1988)
    Need for application of Image processing techniques in astronomical studies in optical wavelengths and special advantages accruing thereby are discussed. The paper describes various image processing facilities that are ...
  • Image Quality Specification for Solar Telescopes 
    Saraswathi Kalyani, S; Sridharan, R (Springer, 2023-01)
    Modern large ground-based solar telescopes are invariably equipped with adaptive optics systems to enhance the high angular resolution imaging and spectroscopic capabilities in the presence of Earth's atmospheric turbulence. ...
  • Imaging and spectral observations of a type-II radio burst revealing the section of the CME-Driven shock that accelerates electrons 
    Majumdar, Satabdwa; Tadepalli, Srikar Paavan; Maity, Samriddhi Sankar; Deshpande, Ketaki; Anshu Kumari; Ritesh Patel; Gopalswamy, Nat (Springer, 2021-04)
    We report on a multi-wavelength analysis of the 26 January 2014 solar eruption involving a coronal mass ejection (CME) and a Type-II radio burst, performed by combining data from various space and ground-based instruments. ...
  • Imaging With The Mauritius Radio Telescope Challenges and Results 
    Udaya Shankar, N; Golap, K; Sachdev, S; Dodson, R; Katwaroo, M; Sastry, Ch. V (Springer, 2002)
    The Mauritius Radio Telescope (MRT) has been built with the main objective of surveying the southern sky at meter wavelengths. MRT is a Fourier synthesis, T-shaped non-coplanar array. It consists of a2048 m long East-West ...
  • IMF polarity effects on the equatorial ionospheric F-region 
    Sastri, J. H (1985)
    An exploratory study is made of the influence, during the equinoxes, of the interplanetary magnetic field (IMF) sector structure on the ionospheric F-region using ionosonde data from several equatorial stations for a 3-yr ...
  • Impact of Aerosol and Cloud on the Solar Energy Potential over the Central Gangetic Himalayan Region 
    Dumka, Umesh Chandra; Kosmopoulos, Panagiotis G; Shantikumar, N. S (Multidisciplinary Digital Publishing Institute, 2021-08)
    We examine the impact of atmospheric aerosols and clouds on the surface solar radiation and solar energy at Nainital, a high-altitude remote location in the central Gangetic Himalayan region (CGHR). For this purpose, we ...
  • Impact of locally suppressed wave sources on helioseismic traveltimes 
    Hanasoge, S. M; Couvidat, S; Rajaguru, S. P; Birch, A. C (Royal Astronomical Society, 2008-12)
    Wave traveltime shifts in the vicinity of sunspots are typically interpreted as arising predominantly from magnetic fields, flows and local changes in sound speed. We show here that the suppression of granulation related ...
  • Impact of photometric variability on age and mass determination in young stellar objects: the case of the Orion Nebula Cluster 
    Messina, S; Parihar, P. S; Distefano, E (IOP Publishing, 2017-06)
    Very young stars, like the Orion Nebula Cluster (ONC) members analysed in the present study, exhibit photometric variability with a wide range of amplitudes. Such a prominent variability reflects in the inferred values of ...
  • Impact of two severe geomagnetic storms on the ionosphere over Indian longitude sector during March-April 2023 
    Rajana, Siva Sai Kumar; Panda, Sampad Kumar; Jade, Sridevi; Vivek, Chiranjeevi G; Upadhayaya, A.K; Bhardwaj, Arti; Jorphail, S; Seemala, Gopi Krishna (Springer, 2024-01)
    We investigated the ionosphere response to the two severe geomagnetic storms in the ascending phase of solar cycle 25 which occurred during the 23-24 March 2023 (SYM-Hmin = −169 nT) and 23-24 April 2023 (SYM-Hmin = −233 ...
  • Impacts of Aerosol Loading in the Hindu Kush Himalayan Region Based on MERRA-2 Reanalysis Data 
    Shantikumar, N. S; Dumka, Umesh Chandra; Mugil, Sivasamy Kalamani; Kuniyal, Jagdish Chandra; Hooda, Rakesh K; Gautam, Alok Sagar; Tiwari, Suresh (MDPI, 2021-10)
    The impacts of climate change have severely affected geosphere, biosphere and cryosphere ecosystems in the Hindu Kush Himalayan (HKH) region. The impact has been accelerating further during the last few decades due to rapid ...
  • Implications of a hot atmosphere/corino from ALMA observations toward NGC 1333 IRAS 4A1 
    Sahu, Dipen; Liu, Sheng-Yuan; Su, Yu-Nung; Li, Zhi-Yun; Lee, Chin-Fei; Hirano, Naomi; Takakuwa, Shigehisa (IOP Publishing, 2019-02-20)
    We report high angular resolution observations of NGC 1333 IRAS 4A, a protostellar binary including A1 and A2, at 0.84 mm with the Atacama Large Millimeter/submillimeter Array. From the continuum observations, we suggest ...
  • Implications of an Extended Dark Energy Model with Massive Neutrinos 
    Sharma, Ravi Kumar; Pandey, Kanhaiya L; Das, Subinoy (American Astronomical Society, 2022-08-01)
    Recently there have been reports of finding a lower bound on the neutrino mass parameter (Σmν) when using the Atacama Cosmology Telescope (ACT) and SPTpol data; however, these bounds on the Σmν are still weaker for most ...
  • The implications of gamma-ray lines observed from the Orion complex 
    Cowsik, R; Friedlander, Michael. W (The American Astronomical Society, 1995-05)
    The observation of intense gamma-ray line emission from the Orion complex, attributed by Bloemen et al. to de-excitation of cosmic-ray carbon and oxygen nuclei, has important implications for emission from Orion in the ...
  • Implications of kHz quasi-periodic brightness oscillations in X-ray binaries for neutron star structure 
    Thampan, A. V; Bhattacharya, D; Datta, B (Blackwell Science Ltd., 1999-02)
    Kilohertz quasi-periodic oscillations (QPOs) in low-mass X-ray binaries (LMXBs) may represent the orbital frequencies of the innermost Keplerian orbits around accreting neutron stars. Attempts have recently been made to ...
  • Implications of Possible Alternate Scenarios for Short and Long Duration GRBs 
    Sivaram, C; Arun, K; Kiren, O. V (Bentham Open, 2014-12)
    Gamma-ray bursts (GRB) are the most luminous physical phenomena in the universe, consisting of flashes of gamma rays that last from seconds to hours. In this paper we look at possible alternate scenarios for both short and ...
  • Implications of Tension-Free Equilibria for Pre-Flare Energy Build UP 
    Venkatakrishnan, P (International Astronomical Union, 1990)
    The downward tension force is known to be the extremely small at the locations of highly sheared magnetic fields. The free energy in such tension free fields is shown to be dependent on the plasma density. The excess of ...
  • Implications of the Crustal Moment of Inertia for Neutron Star Equations of State 
    Datta, B; Alpar, M. A (European Southern Observatory, 1993-08)
    The dynamical models for neutron star glitches and postglitch behaviour, and the information they yield on the crustal moment of inertia, are applied to a catalogue of neutron star models. The implications for neutron star ...
  • Implications of γ-ray lines observed from the orion complex. II 
    Cowsik, R; Friedlander, W. M (International Union of Pure and Applied Physics, 1995)
    The observation of intense gamma-ray line emission from the Orion complex, attributed by Bloemen et al. to de-excitation of cosmic-ray carbon and oxygen nuclei, has important, implications for emission from Orion in the ...

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