IIA Institutional Repository

Browsing by Author "Garcia-Hernandez, D. A"

Browsing by Author "Garcia-Hernandez, D. A"

Sort by: Order: Results:

  • The Carbon Star DY Persei May Be a Cool R Coronae Borealis Variable 
    Garcia-Hernandez, D. A; Kameswara Rao, N; Lambert, David L; Eriksson, K; Reddy, A. B. S; Masseron, Thomas (American Astronomical Society, 2023-05-01)
    Optical and near-IR photometry suggests that the carbon star DY Persei exhibits fadings similar to those of R Coronae Borealis (RCB) variables. Photometric surveys of the Galaxy and Magellanic Clouds uncovered new DY Per ...
  • Detection of CH+, CH and H2 Molecules in the Young Planetary Nebula IC 4997 
    Kameswara Rao, N; Lambert, D. L; Reddy, A. B. S; Manchado, A; Diaz-Luis, J. J; Garcia-Hernandez, D. A (IOP Publishing, 2020-07-01)
    We have detected CH+ and CH molecular absorption lines from the youngcompact planetary nebula IC 4997 from high resolution optical spectra. A high-resolution infra-red (H and K bands) spectrum provides detection of H2 ...
  • The double dust envelopes of R coronae borealis stars 
    Montiel, Edward J; Clayton, G. C; Sugerman, B. E. K; Evans, A; Garcia-Hernandez, D. A; Kameswara Rao, N; Matsuura, M; Tisserand, P (IOP Publishing, 2018-10)
    The study of extended, cold dust envelopes surrounding R Coronae Borealis (RCB) stars began with their discovery by the Infrared Astronomical Satellite. RCB stars are carbon-rich supergiants characterized by their extreme ...
  • Dust Around R Coronae Borealis Stars. II. Infrared Emission Features in an H-poor Environment 
    Garcia-Hernandez, D. A; Kameswara Rao, N; Lambert, D. L (IOP Publishing, 2013-08-20)
    Residual Spitzer/Infrared Spectrograph spectra for a sample of 31 R Coronae Borealis (RCB) stars are presented and discussed in terms of narrow emission features superimposed on the quasi-blackbody continuous infrared ...
  • First evidence of the possible detection of diffuse circumstellar bands in AGB descendants 
    Di­az-Luis, J. J; Garcia-Hernandez, D. A; Kameswara Rao, N; Manchado, A; Cataldo, F (Societa Astronomica Italiana, 2016-06)
    The short transition phase between asymptotic giant branch stars (AGB; when circumstellar envelopes rich in small organic molecules are efficiently created) and planetary nebulae (PNe) represents a most active phase of ...
  • High-resolution Optical Spectroscopy of DY Cen: Diffuse Interstellar Bands in a Proto-fullerene Circumstellar Environment? 
    Garcia-Hernandez, D. A; Kameswara Rao, N; Lambert, D. L (IOP Publishing, 2012-11-01)
    We search high-resolution and high-quality VLT/UVES optical spectra of the hot R Coronae Borealis star DY Cen for electronic transitions of the C60 molecule and diffuse interstellar bands (DIBs). We report the non-detection ...
  • A New Near-IR C2 Linelist for an Improved Chemical Analysis of Hydrogen-deficient, Carbon-rich Giants\unboldmath 
    Garcia-Hernandez, D. A; Masseron, T; Zamora, O; Manchado, A; Rao, N. K; Reddy, A. B. S; Lambert, D. L; Yurchenko, S; Tennyson, J (Astronomical Society of the Pacific, 2019)
    Diatomic carbon (C2) is ubiquitous in astronomical environments, from comets and stars to translucent clouds and the interstellar medium. In particular, the C2 bands (mainly the Ballik-Ramsay and Phillips transitions) are ...
  • Oxygen isotopic ratios in cool R coronae borealis stars 
    Garcia-Hernandez, D. A; Lambert, D. L; Kameswara Rao, N; Hinkle, K. H; Eriksson, K (Institute of Physics, 2010-05)
    We investigate the relationship between R Coronae Borealis (RCB) stars and hydrogen-deficient carbon (HdC) stars by measuring precise 16O/18O ratios for five cool RCB stars. The 16O/18O ratios are derived by spectrum ...
  • A search for diffuse bands in fullerene planetary nebulae: evidence of diffuse circumstellar bands 
    Diaz-Luis, J. J; Garcia-Hernandez, D. A; Kameswara Rao, N; Manchado, A; Cataldo, F (EDP Sciences, 2015-01)
    Large fullerenes and fullerene-based molecules have been proposed as carriers of diffuse interstellar bands (DIBs). The recent detection of the most common fullerenes (C60 and C70) around some planetary nebulae (PNe) now ...

Search DSpace

Browse

My Account