IIA Institutional Repository

Browsing by Subject "Techniques: spectroscopic"

Browsing by Subject "Techniques: spectroscopic"

Sort by: Order: Results:

  • The 1999 Outburst of the Recurrent Nova U Scorpii 
    Anupama, G. C; Dewangan, G. C (The American Astronomical Society, 2000-03)
    The optical spectra of the recurrent nova U Sco obtained in five epochs 0.45-42.35 days after the 1999 outburst maximum are presented here. For the first time, an outburst spectrum of U Sco has been obtained as early as ...
  • The 2010 outburst and pre-outburst optical spectrum of the recurrent nova U Scorpii 
    Anupama, G. C; Kamath, U. S; Ramaprakash, A. N; Kantharia, N. G; Hegde, M; Mohan, V; Kulkarni, M; Bode, M. F; Eyres, S. P. S; Evans, A; O Brien, T. J (EDP Sciences, 2013-11)
    Aims. We study the evolution of the recurrent nova U Scorpii during its outburst in 2010. Methods. Optical spectroscopic observations of the nova were obtained during 0.83–162.5 days after outburst maximum. Optical ...
  • Activity of the first interstellar comet 2I/Borisov around perihelion: results from Indian observatories 
    Aravind, K; Ganesh, Shashikiran; Venkataramani, Kumar; Sahu, D. K; Angchuk, D; Sivarani, T; Unni, Athira (Oxford University Press on behalf of the Royal Astronomical Society, 2021-04)
    Comet 2I/Borisov is the first true interstellar comet discovered. Here, we present results from observational programs at two Indian observatories, 2 m Himalayan Chandra Telescope at the Indian Astronomical Observatory, ...
  • Broad-line Type Ic supernova SN 2014ad 
    Sahu, D. K; Anupama, G. C; Chakradhari, N. K; Srivastav, S; Tanaka, M; Maeda, K; Nomoto, K (Oxford University Press on behalf of the Royal Astronomical Society, 2018-04)
    We present optical and ultraviolet photometry and low-resolution optical spectroscopy of the broad-line Type Ic supernova SN 2014ad in the galaxy PGC 37625 (Mrk 1309), covering the evolution of the supernova during −5 to ...
  • Complex Variations in the Line-Intensity Ratio of Coronal Emission Lines with Height above the Limb 
    Singh, J; Sakurai, T; Ichimoto, K; Watanabe, T (IOP Publishing, 2004-12-10)
    We obtained spectroscopic observations simultaneously in pairs of coronal emission lines, one line being [Fe X] λ6374 and the other line being [Fe XI] λ7892, [Fe XIII] λ10747, or [Fe XIV] λ5303, and we studied the variations ...
  • Decoding the compositions of four bright r-process-enhanced stars 
    Saraf, Pallavi; Prieto, Carlos Allende; Sivarani, T; Bandyopadhyay, A; Beers, Timothy C.; Susmitha, A (Oxford University Press on behalf of Royal Astronomical Society, 2023-10)
    There has been a concerted effort in recent years to identify the astrophysical sites of the r-process that can operate early in the galaxy. The discovery of many r-process-enhanced (RPE) stars (especially by the R-process ...
  • Disentangling the two sub-populations of early Herbig Be stars using VLT/X-shooter spectra 
    Shridharan, B; Mathew, B; Arun, R; Cysil, T. B; Subramaniam, A; Manoj, P; Maheswar, G; Sudheesh, T. P (EDP Sciences, 2023-11)
    Early Herbig Be (HBe) stars are massive, young stars accreting through the boundary layer mechanism. However, given the rapid (<2 Myr) evolution of early Herbig stars to the main-sequence phase, studying the evolution of ...
  • Emission line star catalogues post-Gaia DR3: A validation of Gaia DR3 data using the LAMOST OBA emission catalogue 
    Shridharan, B; Mathew, B; Bhattacharyya, S; Robin, T; Arun, R; Kartha, S. S; Manoj, P; Nidhi, S; Maheswar, G; Paul, K. T; Narang, M; Himanshu, T (EDP Sciences, 2022-12)
    Aims. Gaia Data Release 3 (DR3) and further releases have the potential to identify and categorise new emission-line stars in the Galaxy. We perform a comprehensive validation of astrophysical parameters from Gaia DR3 ...
  • Evolution of emission line activity in intermediate mass young stars 
    Manoj, P; Bhatt, H. C; Maheswar, G; Muneer, S (American Astronomical Society, 2006-12-10)
    We present optical spectra of 45 intermediate-mass Herbig Ae/Be stars. Together with the multiepoch spectroscopic and photometric data compiled for a large sample of these stars and ages estimated for individual stars by ...
  • Excitation Mechanism of O i Lines in Herbig Ae/Be Stars 
    Mathew, v; Manoj, P; Narang, Mayank; Banerjee, D. P. K; Pratheeksha Nayak; Muneer, S; Vig, S; Kumar, S. P; Paul, K. T; Maheswar, G (IOP Publishing, 2018-04-10)
    We have investigated the role of a few prominent excitation mechanisms viz. collisional excitation, recombination, continuum fluorescence, and Lyman beta fluorescence on the O i line spectra in Herbig Ae/Be stars. The aim ...
  • Exploring the optical behaviour of a Type Iax supernova SN 2014dt 
    Singh, M; Misra, K; Sahu, D. K; Dastidar, R; Gangopadhyay, A; Bose, S; Srivastav, S; Anupama, G. C; Chakradhari, N. K; Brajesh Kumar; Kumar, B; Pandey, S. B (Oxford University Press on behalf of the Royal Astronomical Society, 2018-02)
    We present optical photometric (up to ∼ 410 d since B max ) and spectroscopic (up to ∼ 157 d since B max ) observations of a Type Iax supernova (SN) 2014dt located in M61. SN 2014dt is one of the brightest and ...
  • A global look into the world of interacting supernovae 
    Gangopadhyay, Anjasha; Misra, Kuntal; Kawabata, Koji; Dastidar, Raya; Singh, Mridweeka (Indian Academy of Sciences, 2022-12)
    Interacting supernovae (SNe) IIn and Ibn show narrow emission lines and have always been a mysterious and unsolved genre in SNe physics. We present a comprehensive analysis of the temporal and spectroscopic behavior of ...
  • Highly Reddened Type Ia Supernova SN 2004ab: Another Case of Anomalous Extinction 
    Chakradhari, N. K; Sahu, D. K; Anupama, G. C; Prabhu, T. P (Oxford University Press on behalf of the Royal Astronomical Society, 2018-02)
  • A laser-lock concept to reach cm-1s-precision in Doppler experiments with Fabry-Perot wavelength calibrators 
    Reiners, A; Banyal, R. K; Ulbrich, R. G (EDP Sciences, 2014-09)
    State-of-the-art Doppler experiments require wavelength calibration with precision at the cm s − 1 level. A low-finesse Fabry-Pérot interferometer (FPI) can provide a wavelength comb with a very large ...
  • [O/Fe] Estimates for Carbon-enhanced Metal-poor Stars from Near-infrared Spectroscopy 
    Kennedy, C. R; Sivarani, T; Beers, T. C; Lee, Y. S; Placco, V. M; Rossi, S; Christlieb, N; Herwig, F; Plez, B (IOP Publishing, 2011-03)
    We report on oxygen abundances determined from medium-resolution near-infrared spectroscopy for a sample of 57 carbon-enhanced metal-poor (CEMP) stars selected from the Hamburg/ESO Survey. The majority of our program stars ...
  • Observational properties of a type Ib supernova MASTER OT J120451.50+265946.6 in NGC 4080 
    Singh, M; Misra, K; Sahu, D. K; Dastidar, R; Gangopadhyay, A; Srivastav, S; Anupama, G. C; Bose, S; Lipunov, V; Chakradhari, N. K; Brajesh Kumar; Pandey, S. B; Gorbovskoy, E; Balanutsa, P (Oxford University Press on behalf of the Royal Astronomical Society, 2019-06)
    MASTER OT J120451.50+265946.6 (M12045), discovered by the MASTER Global Robotic Net, is a Type Ib supernova (SN) that exploded in NGC 4080. We present the BVRI photometric and spectroscopic observations up to ∼250 d since ...
  • On the observational behaviour of the highly polarized Type IIn supernova SN 2017hcc 
    Brajesh Kumar; Eswaraiah, C; Singh, A; Sahu, D. K; Anupama, G. C; Kawabata, K. S; Yamanaka, Masayuki; Otsubo, Ikki; Pandey, S. B; Nakaoka, Tatsuya; Kawabata, Miho; Aryan, Amar; Akitaya, Hiroshi (Oxford University Press on behalf of the Royal Astronomical Society, 2019-09)
    We present the results based on photometric (Swift UVOT), broad-band polarimetric (V and Rbands) and optical spectroscopic observations of the Type IIn supernova (SN) 2017hcc. Our study is supplemented with spectropolarimetric ...
  • One year of monitoring of the Type IIb supernova SN 2011dh 
    Sahu, D. K; Anupama, G. C; Chakradhari, N. K (Oxford University Press on behalf of the Royal Astronomical Society, 2013-07-21)
    Optical UBVRI photometry and low-resolution spectroscopy of the Type IIb supernova SN 2011dh in M51 are presented, covering the first year after the explosion. The light curve and spectral evolution are discussed. The early ...
  • Optical and Near-infrared Study of Nova V2676 Oph 2012 
    Raj, A; Das, R. K; Walter, F. M (IOP Publishing, 2017-02-01)
    We present optical spectrophotometric and near-infrared (NIR) photometric observations of the nova V2676 Oph covering the period from 2012 March 29 through 2015 May 8. The optical spectra and photometry of the nova have ...
  • Optical characterization and radial velocity monitoring with Belgian and Indian telescopes (ORBIT): the eclipsing binaries EPIC 211982753 and EPIC 211915147 
    Panchal, Alaxender; Joshi, Y. C; De Cat, Peter; Lampens, Patricia; Goswami, A; Tiwari, S. N (Oxford University Press on behalf of Royal Astronomical Society, 2023-05)
    The K2 eclipsing binary (EB) candidates EPIC 211982753 (hereinafter called EPIC2753) and EPIC 211915147 (hereinafter called EPIC5147) are characterized with the help of photometric and high-resolution spectroscopic data. ...

Search DSpace

Browse

My Account