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Browsing by Author "Reddy, B. E"

Browsing by Author "Reddy, B. E"

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  • A large sample of newly identified carbon-deficient red giants from APOGEE 
    Maben, Sunayana; Bharat Kumar, Y; Reddy, B. E; Campbell, Simon W; Zhao, Gang (Oxford University Press on behalf of Royal Astronomical Society, 2023-11)
    Based on the Apache Point Observatory Galactic Evolution Experiment survey we conducted a search for carbon-deficient red giants (CDGs). We found 103 new CDGs, increasing the number in the literature by more than a factor ...
  • Li Abundance Survey in Galactic Thin Disk 
    Lambert, D. L; Reddy, B. E (Astronomical Society of the Pacific, 2005-09)
    Lithium abundances for a sample of 451 F and G dwarfs including 181 new stars all belonging to the Galactic thin disk are discussed. Lithium abundances, metallicities ([Fe/H]), masses, and ages are determined (Lambert & ...
  • Lithium Abundances in Giants as a Function of Stellar Mass: Evidence for He Flash as the Source of Li Enhancement in Low-mass Giants 
    Mallick, Anohita; Raghubar Singh; Reddy, B. E (American Astronomical Society, 2023-02-10)
    In this work, we studied the distribution of lithium abundances in giants as a function of stellar mass. We used a sample of 1240 giants common among Kepler photometric and LAMOST medium-resolution (R ≈ 7500) spectroscopic ...
  • Lithium abundances of the local thin disc stars 
    Lambert, D. L; Reddy, B. E (Royal Astronomical Society, 2004-04-01)
    Lithium abundances are presented for a sample of 181 nearby F and G dwarfs with accurate Hipparcos parallaxes. The stars are on circular orbits about the Galactic centre and, hence, are identified as belonging to the thin ...
  • Lithium enrichment in the Galaxy: A study using the GALAH and Gaia surveys 
    Deepak; Reddy, B. E (Cambridge University Press, 2019-06)
    Here, we explore the enrichment of Lithium in the Galaxy using a large sample of stars common among large spectroscopic surveys such as the GALAH and astrometric survey by the Gaia satellite. For this study we used about ...
  • Lithium in the Galaxy: current status and contribution from the low-mass giants? 
    Deepak; Reddy, B. E (Societa Astronomica Italiana, 2020)
    We discuss the evolution of Li in the Galaxy based on a large sample of dwarfs and giants collected from the cross-match of the Gaia and GALAH surveys. Data spans a wide range in metallicity and cover various Galactic ...
  • Moving groups in the galactic disc 
    Ramya, P; Reddy, B. E (Cambridge University Press, 2014-01)
    We present results of chemical abundance study of a few representative stellar streams of Galactic thick and thin discs. Arcturus stream, which was proposed to have an extragalactic origin, and a recently detected stream ...
  • Origin of Lithium Enrichment in K Giants 
    Bharat Kumar, Y; Reddy, B. E; Lambert, D. L (Institute of Physics Publishing, 2011-03-20)
    In this Letter, we report on a low-resolution spectroscopic survey for Li-rich K giants among 2000 low-mass (M ≤ 3 M sun) giants spanning the luminosity range from below to above the luminosity of the clump. Fifteen new ...
  • Post-AGB A-F supergiant stars 
    Parthasarathy, M; Reddy, B. E (Astronomical Society of India, 1993)
    We have searched the IRAS Polar Stratospheric Clouds (PSC) for dust shells around A-F supergiant stars similar to the high galactic latitude A-F supergiants with circumstellar dust shells. We have found that HD 114855 ...
  • Probing infrared excess connection with Li enhancement among red clump giants 
    Mallick, Anohita; Reddy, B. E; Muthumariappan, C (Oxford University Press on behalf of Royal Astronomical Society, 2022-04)
    We have performed a search among low-mass red giants for finding evidence for merger scenario for triggering He-flash and subsequent Li enhancement. We chose a sample of red giants from GALAH survey with well-measured Li ...
  • R Coronae Borealis stars at minimum light - UW Cen 
    Kameswara Rao, N; Reddy, B. E; Lambert, D. L (Blackwell Publishing, 2004-12)
    Two high-resolution optical spectra of the R Coronae Borealis (R CrB) star UW Cen in decline are discussed. A spectrum from mid-1992 when the star had faded by 3 mag shows just a few differences with the spectrum at maximum ...
  • Radial velocity comparison of Gaia DR2 and RAVE DR5 survey: A systematic offset in radial velocities among a group of highly accurate radial velocity stars 
    Deepak; Reddy, B. E (IOP Publishing, 2018-10)
    Here, we report a comparative study of radial velocity (RV) data of two major surveys: Gaia Data Release 2 and RAVE Data Release 5. We restricted the sample to stars with relatively accurate RVs. The difference between ...
  • A road map for the generation of a near-infrared guide star catalog for thirty meter telescope observations 
    Subramanian, S; Subramaniam, A; Sivarani, T; Simard, Luc; Anupama, G. C; Gillies, Kim; Ramaprakash, A. N; Reddy, B. E (Indian Academy of Sciences, 2016-09)
    The near-infrared instruments in the upcoming Thirty Meter Telescope (TMT) will be assisted by a multi conjugate Adaptive Optics (AO) system. For the efficient operation of the AO system, during observations, a near-infrared ...
  • Searching for the metal-weak thick disc in the solar neighbourhood 
    Reddy, B. E; Lambert, D. L (Royal Astronomical Society, 2008-11)
    An abundance analysis is presented of 60 metal-poor stars drawn from catalogues of nearby stars provided by Arifyanto et al. and Schuster et al. In an attempt to isolate a sample of metal-weak thick disc stars, we applied ...
  • SN 1993J in M 81: Optical photometry and spectrophotometry during the first two months 
    Prabhu, T. P; Mayya, Y. D; Singh, K. P; Kameswara Rao, N; Ghosh, K. K; Mekkaden, M. V; Pati, A. K; Raveendran, A. V; Reddy, B. E; Sagar, R; Subramaniam, A; Surendiranath, R (The European Southern Observatory, 1995-03)
    CCD photometric and spectrophotometric data on the type IIb supernova 1993J in M 81 (NGC 3031) obtained from Vainu Bappu Observatory, Kavalur, during the first two months since the outburst are reported. The evolution of ...
  • Spectroscopic study of two new super Li-rich red clump K giants 
    Raghubar, Singh; Reddy, B. E; Bharat Kumar, Y (Oxford University Press on behalf of the Royal Astronomical Society, 2019-01)
    In this paper, we report the discovery of two new super Li-rich K giants: HD 24960 and TYC 1751-1713-1. Based on high-resolution (R ≈ 60 000) spectroscopy, we have derived Li abundance of A(Li) ≈ 4.0 dex for both ...
  • Spectroscopy of IRAS sources with far IR colors similar to those of planetary nebulae 
    Reddy, B. E; Parthasarathy, M (Astronomical Society of India, 1993)
    Optical candidates of 17 unidentified IRAS sources with far-infrared colors similar to planetary nebulae have been detected on sky survey plates. Low resolution CCD spectra of seven optical candidates suggests that they ...
  • Stellar streams in the Galactic thick disk: preliminary results 
    Ramya, P; Reddy, B. E (Astronomical Society of India, 2012)
    Here we report preliminary results of our study of chemical tagging of member stars of two Galactic stellar streams. Both the streams, kinematically belong to the thick disk component of the Galaxy. We analysed high ...
  • Studies of Post-AGB Stars and Proto-planetary Nebulae 
    Reddy, B. E (Indian Institute of Astrophysics, 1996-08)
  • Study of Lithium-rich giants with the GALAH spectroscopic survey 
    Deepak; Reddy, B. E (Oxford University Press on behalf of the Royal Astronomical Society, 2019-04)
    In this article, we speculate on the possible mechanisms for Li enhancement origin in RGB stars based on a large data set of around 340 299 stars collected from the GALAH survey combined with the Gaia astrometry. Data has ...

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