IIA Institutional Repository

Browsing by Author "Kumar, B"

Browsing by Author "Kumar, B"

Sort by: Order: Results:

  • Light Curve and Spectral Evolution of Type IIb Supernovae 
    Gangopadhyay, A; Misra, K; Pastorello, A; Sahu, D. K; Singh, M; Dastidar, R; Anapuma, G. C; Kumar, B; Pandey, S. B (Societe Royale des Sciences de Liege, 2018-04)
    Stripped-Envelope Supernovae constitute the sub-class of core-collapse supernovae that strip off their outer hydrogen envelope due to high stellar winds or due to interaction with a binary companion where mass transfer ...
  • The Multi Application Solar Telescope 
    Venkatakrishnan, P; Mathew, S. K; Srivastava, N; Bayanna, A. R; Kumar, B; Ramya, B; Jain, N; Saradava, M (Current Science Association, 2017-08)
    Multi Application Solar Telescope (MAST), a telescope for the detailed study of solar activity, was operationalized at the Udaipur Solar Observatory (USO) of Physical Research Laboratory (PRL), on 16 June 2015. This ...
  • Observations with the 3.6-meter Devasthal optical telescope 
    Sagar, R; Kumar, B; Sharma, S (Indian Academy of Sciences, 2020-12)
    The 3.6-meter Indo–Belgian Devasthal optical telescope (DOT) has been used for optical and near-infrared (NIR) observations of celestial objects. The telescope has detected stars of B=24.5±0.2,R=24.6±0.12 and g=25.2±0.2 ...
  • On mass and velocity distributions in members of star clusters: An analytical approach 
    Chatterjee, S; Kumar, B; Sagar, R (Astronomical Society of India, 2002-12)
    Dynamical evolution of stellar mass distribution in star clusters is analysed by considering simultaneously the effects of dynamical friction, stochastic heating and the gravitational potential due to mass distribution ...
  • On the flare induced high-frequency global waves in the sun 
    Kumar, B; Mathur, S; García, R. A; Venkatakrishnan, P (Institute of Physics, 2010-03-01)
    Recently, Karoff & Kjeldsen presented evidence of strong correlation between the energy in the high-frequency part (5.3 < ν < 8.3 mHz) of the acoustic spectrum of the Sun and the solar X-ray flux. They have used disk-integrated ...
  • On the line profile changes observed during the X2.2 class flare in the active region NOAA 11158 
    Bayanna, A. R; Kumar, B; Venkatakrishnan, P; Mathew, S. K; Ravindra, B; Mathur, S; Garcia, R. A (IOP Publishing, 2014-02)
    The solar active region NOAA 11158 produced a series of flares during its passage through the solar disk. The first major flare (of class X2.2) of the current solar cycle occurred in this active region on 2011 February 15 ...
  • On the power and frequency of p-modes in sunspots 
    Kumar, B; Tripathy, S. C; Jain, R; Deshpande, M. R (Astronomical Society of India, 2000)
    A time series of GONG Dopplergrams has been used to measure the velocity fluctuations in the sunspot and quiet photosphere simultaneously. The power spectrum analysis shows that the power of the predominant p-mode is reduced ...
  • On the Rapid Variations of Solar Magnetic Fields 
    Venkatakrishnan, P; Kumar, B; Ravindra, B (Astronomical Society of India, 2003)
    We report on the rapid variations of solar magnetic fields that appear to be enhanced significantly above the background variability, at a few locations within the solar active regions, as observed with the Michelson Doppler ...
  • Optical and near-infrared photometric study of the open cluster NGC 637 and 957 
    Yadav, R. K. S; Kumar, B; Subramaniam, A; Sagar, R; Mathew, B (Royal Astronomical Society, 2008-11)
    We present UBVRI CCD photometry in the region of the open clusters NGC 637 and 957. The radii are found to be 4.2 and 4.3 arcmin. Their reddenings E(B - V) are 0.64 +/- 0.05 and 0.71 +/- 0.05 mag and their distances, from ...
  • Optical and NIR observations of the nearby type Ia supernova SN 2014J 
    Srivastav, S; Ninan, J. P; Kumar, B; Anupama, G. C; Sahu, D. K; Ojha, D. K; Prabhu, T. P (Oxford University Press on behalf of the Royal Astronomical Society, 2016-03)
    Optical and NIR observations of the Type Ia supernova SN 2014J in M82 are presented. The observed light curves are found to be similar to normal Type Ia supernovae (SNe Ia), with a decline rate parameter m 15 ( B ...
  • Optical observations of supernova 2012aw 
    Bose, S; Kumar, B; Sutaria, F. K; Roy, Rupak; Kumar, B; Bhatt, V. K; Chakraborti, S (Cambridge University Press, 2014-01)
    We present optical UBVRI photometric and low-resolution spectroscopic follow-up observations of a type II SN 2012aw in a nearby (~10 Mpc) galaxy M95 during 4 to 270 days post-explosion. The evolution characteristics of ...
  • The optical photometric and spectroscopic investigation of type IIP supernova 2012A 
    Roy, R; Sutaria, F. K; Bose, S; Johnson, S; Dwarkadas, V; York, B; Kumar, B; Kumar, B; Bhatt, V. K; Chakraborti, S; York, D; Ritchey, A; Saurage, G; Kaiser, M B (Cambridge University Press, 2014-01)
    Supernova 2012A was discovered on 7.39UT, January, 2012 in the nearby galaxy NGC 3239 at an unfiltered magnitude of 14.6 and classified spectroscopically as a Type IIP event. Here, we present the optical photometric and ...
  • Performance Evaluation of Adaptive Optics Systems 
    Sridharan, R; Raja Bayanna, A; Srivastava, N; Kumar, B; Ravindra, B; Gupta, S. K; Jain, N; Ambastha, A; Venkatakrishnan, P (Astronomical Society of India, 2003)
    Adaptive Optics (AO) systems improve the resolution of ground based telescopes and allow for long exposure images. Their performance depends on the seeing conditions at the time of observations. In this paper, we evaluate ...
  • Photometric and polarimetric observations of fast declining Type II supernovae 2013hj and 2014G 
    Bose, S; Kumar, B; Misra, K; Matsumoto, K; Brajesh Kumar; Singh, M; Fukushima, D; Kawabata, M (Oxford University Press on behalf of the Royal Astronomical Society, 2016-01)
    We present broad-band photometric and polarimetric observations of two Type II supernovae (SNe) 2013hj and 2014G. SN 2014G is a spectroscopically classified Type IIL event, which we also confirm photometrically because ...
  • Photometry and low resolution spectroscopy of hot post-AGB candidates 
    Gauba, G; Parthasarathy, M; Kumar, B; Yadav, R. K. S; Sagar, R (The European Southern Observatory, 2003-06)
    We have obtained Johnson U, B, V and Cousins R, I photometry and low resolution spectra of a small sample of hot post-AGB candidates. Using the present data in combination with JHK data from 2MASS, infrared data from the ...
  • Present status of the 4-m ILMT data reduction pipeline: application to space debris detection and characterization 
    Pradhan, B; Delchambre, L; Akhunov, T; Hickson, P; Bartczak, P; Kumar, B; Surdej, J (Societe Royale des Sciences de Liege, 2018-04)
    The 4-m International Liquid Mirror Telescope (ILMT) located at the ARIES Observatory (Devasthal, India) has been designed to scan at a latitude of +29◦ 22’ 26” a band of sky having a width of about half a degree in the ...
  • Probing into emission mechanisms of GRB 190530A using time-resolved spectra and polarization studies: synchrotron origin? 
    Gupta, Rahul; Gupta, S; Chattopadhyay, T; Lipunov, V; Castro-Tirado, A. J; Bhattacharya, D; Pandey, S. B; Oates, S. R; Kumar, Amit; Hu, Y-D; Valeev, A. F; Minaev, P. Yu; Kumar, H; Vinko, J; Dimple; Sharma, V; Aryan, A; Castellon, A; Gabovich, A; Moskvitin, A; Ordasi, A; Pal, A; Pozanenko, A; Zhang, B-B; Kumar, B; Svinkin, D; Saraogi, D; Vlasenko, D; Fernandez-Garcia, E; Gorbovskoy, E; Anupama, G. C; Misra, K; Sarneczky, K; Kriskovics, L; Castro-Tirado, M. A; Caballero-Garcia, M. D; Tiurina, N; Balanutsa, P; Lopez, R. R; Sanchez-Ramirez, R; Szakats, R; Belkin, S; Guziy, S; Iyyani, S; Tiwari, S. N; Vadawale, Santosh V; Sun, T; Bhalerao, V; Kornilov, V; Sokolov, V. V (Oxford University Press on behalf of Royal Astronomical Society, 2022-04)
    Multipulsed GRB 190530A, detected by the Gamma-ray Burst Monitor (GBM) and Large Area Telescope onboard Fermi, is the sixth most fluent GBM burst detected so far. This paper presents the timing, spectral, and polarimetric ...
  • Radio observations of a nearby type IIP SN 2012aw 
    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 ...
  • A relation between frequency shift and the changes in activity indices 
    Jain, K; Tripathy, S. C; Kumar, B; Bhatnagar, A (Astronomical Society of India, 2000)
    We present a linear relation between the shift in p-mode frequencies and variation in two solar activity indices, namely the sunspot number and 10.7 cm radio flux. From this relation, an empirical model is constructed to ...
  • Scientific capabilities and advantages of the 3.6 meter optical telescope at Devasthal, Uttarakhand 
    Omar, A; Kumar, B; Maheswar, G; Sagar, R (Current Science Association, 2015-08)
    India’s largest 3.6 m aperture optical telescope has been successfully installed in the central Himalayan region at Devasthal, Nainital district, Uttarakhand. The primary mirror of the telescope uses the active optics ...

Search DSpace

Browse

My Account