Now showing items 1-20 of 88

    • 8-13 mu m dust emission features in Galactic bulge planetary nebulae 

      Casassus Montero, Simón; Roche, P. F.; Aitken, D. K.; Smith, C. H. (BLACKWELL SCIENCE LTD, 2001-11-01)
      A sample of 25 infrared-bright planetary nebulae (PNe) towards the Galactic bulge is analysed through 8-13 mum spectroscopy. The classification of the warm dust emission features provides a measure of the C/O chemical ...
    • A centimetre-wave excess over free–free emission in planetary nebulae 

      Casassus Montero, Simón; Nyman, L. A.; Dickinson, C.; Pearson, T. J. (WILEY-BLACKWELL, 2007-12-21)
      We report a centimetre-wave (cm-wave, 5-31 GHz) excess over free-free emission in planetary nebulae (PNe). Accurate 31- and 250-GHz measurements show that the 31-GHz flux densities in our sample are systematically higher ...
    • Accretion kinematics through the warped transition disk in hd142527 from resolved CO(6-5) observations 

      Casassus Montero, Simón; Marino Estay, Sebastián; Pérez, S.; Román, P.; Dunhill, A.; Armitage, P. J.; Cuadra, J.; Wootten, A.; Van der Plas, Gerrit; Cieza, L.; Moral, Víctor; Christiaens, V.; Montesinos, Matías (IOP Publishing, 2015)
      The finding of residual gas in the large central cavity of the HD 142527 disk motivates questions regarding the origin of its non-Keplerian kinematics and possible connections with planet formation. We aim to understand ...
    • ALMA 1.3 mm map of the HD 95086 system 

      Su, Kate Y. L.; MacGregor, Meredith A.; Booth, Mark; Wilner, David J.; Flaherty, Kevin; Hughes, A. Meredith; Phillips, Neil M.; Malhotra, Renu; Hales, Antonio S.; Morrison, Sarah; Ertel, Steve; Matthews, Brenda C.; Dent, William R. F.; Casassus Montero, Simón (IOP Publishing Ltd., 2017)
      Planets and minor bodies such as asteroids, Kuiper-Belt objects, and comets are integral components of a planetary system. Interactions among them leave clues about the formation process of a planetary system. The signature ...
    • An 80 au cavity in the disk around HD 34282 

      Van der Plas, Gerrit; Menard, F.; Canovas, H.; Avenhaus, H.; Casassus Montero, Simón; Pinte, Christophe; Cáceres, C.; Cieza, L. (EDP Sciences, 2017)
      Context. Large cavities in disks are important testing grounds for the mechanisms proposed to drive disk evolution and dispersion, such as dynamical clearing by planets and photoevaporation. Aims. We aim to resolve the ...
    • An inner warp in the DoAr 44 T Tauri transition disc 

      Casassus Montero, Simón; Avenhaus, Henning; Pérez, Sebastián; Navarro, Víctor; Cárcamo, Miguel; Marino, Sebastián; Cieza, Luca; Quanz, Sascha P.; Alarcón, Felipe; Zurlo, Alice; Osses Alvarado, Axel; Rannou, Fernando R.; Román, Pablo E.; Barraza, Marcelo (Oxford University Press, 2018-07)
      Optical/IR images of transition discs (TDs) have revealed deep intensity decrements in the rings of HAeBes HD 142527 and HD 100453 that can be interpreted as shadowing from sharply tilted inner discs, such that the outer ...
    • ANOMALOUS MICROWAVE EMISSION FROM THE H II REGION RCW175 

      Casassus Montero, Simón (IOP PUBLISHING LTD, 2009-01-10)
      We present evidence for anomalous microwave emission in the RCW175 H II region. Motivated by 33 GHz 13' resolution data from the Very Small Array (VSA), we observed RCW175 at 31 GHz with the Cosmic Background Imager ( CBI) ...
    • Anomalous radio emission from dust in the Helix 

      Casassus Montero, Simón; Readhead, A. C. S.; Pearson, T. J.; Nyman, L. A.; Shepherd, M. C.; Bronfman Aguiló, Leonardo (UNIV CHICAGO PRESS, 2004-03-10)
      A by-product of experiments designed to map the cosmic microwave background is the recent detection of a new component of foreground Galactic emission. The anomalous foreground at similar to 10 - 30 GHz, unexplained by ...
    • Atomic gas in debris discs 

      Hales, Antonio S.; Barlow, M. J.; Crawford, I. A.; Casassus Montero, Simón (Oxford University, 2017)
      We have conducted a search for optical circumstellar absorption lines in the spectra of 16 debris disc host stars. None of the stars in our sample showed signs of emission line activity in either Hα, CaII or Na I, confirming ...
    • Azimuthal asymmetries in the debris disk around HD61005 A massive collision of planetesimals? 

      Olofsson, J.; Samland, M.; Avenhaus, Henning; Cáceres, C.; Henning, Thomas; Moor, A.; Milli, Julien; Cánovas, Héctor; Quanz, Sascha; Schreiber, Matthias; Augereau, J. C.; Bayo, A.; Bazzon, A.; Beuzit, J.L.; Boccaletti, Anthony; Buenzli, E.; Casassus Montero, Simón; Chauvin, G.; Dominik, C.; Desidera, S.; Feldt, M.; Gratton, R.; Janson, M.; Lagrange, Anne Marie; Langlois, Maud; Lannier, J.; Maire, Anne-Lise; Mesa, D.; Pinte, Christophe; Rouan, D.; Salter, G.; Thalmann, Christian; Vigan, A. (EDP Sciences, 2016)
      Context. Debris disks off er valuable insights into the latest stages of circumstellar disk evolution, and can possibly help us to trace the outcomes of planetary formation processes. In the age range 10 to 100 Myr, most ...
    • Bayesian image reconstruction based on Voronoi diagrams 

      Cabrera, G. F.; Casassus Montero, Simón; Hitschfeld Kahler, Nancy (UNIV CHICAGO PRESS, 2008-01-10)
      We present a Bayesian Voronoi image reconstruction ( VIR) technique for interferometric data. Bayesian analysis applied to the inverse problem allows us to derive the a posteriori probability of a novel parameterization ...
    • Bayesian Image Reconstruction Based on Voronoi Diagrams 

      Cabrera Vives, Guillermo (Universidad de ChilePrograma Cybertesis, 2008)
    • Cavity and other radial substructures in the disk around HD 97048 

      Van Der Plas, G.; Wright, C. M.; Ménard, F.; Casassus Montero, Simón; Cánovas, H.; Pinte, C.; Maddison, S. T.; Maaskant, K.; Avenhaus, H.; Cieza, L.; Pérez, S.; Ubach, C. (EDP Sciences, 2017)
      Context. Gaps, cavities, and rings in circumstellar disks are signposts of disk evolution and planet-disk interactions. We follow the recent suggestion that Herbig Ae/Be disks with a flared disk harbor a cavity, and ...
    • Centimetre-wave continuum radiation from the rho Ophiuchi molecular cloud 

      Casassus Montero, Simón; Dickinson, Clive; Cleary, Kieran; Paladini, Roberta; Etxaluze, Mireya; Lim, Tanya; White, Glenn J.; Burton, Michael; Indermuehle, Balt; Stahl, Otmar; Roche, Patrick (BLACKWELL PUBLISHING, 2008-12-11)
      The rho Oph molecular cloud is undergoing intermediate-mass star formation. Ultraviolet radiation from its hottest young stars heats and dissociates exposed layers, but does not ionize hydrogen. Only faint radiation from ...
    • Circumbinary, not transitional: on the spiral arms, cavity, shadows, fast radial flows, streamers, and horseshoe in the HD 142527 disc 

      Price, Daniel J.; Cuello, Nicolás; Pinte, Christophe; Mentiplay, Daniel; Casassus Montero, Simón; Christiaens, Valentin; Kennedy, Grant M.; Cuadra, Jorge; Pérez M., Sebastián; Marino, Sebastian; Armitage, Philip J.; Zurlo, Alice; Juhasz, Attila; Ragusa, Enrico; Laibe, Guillaume; Lodato, Giuseppe (Oxford University Press, 2018-06)
      We present 3D hydrodynamical models of the HD 142527 protoplanetary disc, a bright and well-studied disc that shows spirals and shadows in scattered light around a 100 au gas cavity, a large horseshoe dust structure in mm ...
    • Co gas inside the protoplanetary disk cavity in HD142527: disk structure from ALMA 

      Pérez, S.; Casassus Montero, Simón; Ménard, Francois; Román, P.; Van der Plas, Gerrit; Cieza, L.; Pinte, Christophe; Christiaens, V.; Hales, A. (IOP Pub, 2015)
      Inner cavities and annular gaps in circumstellar disks are possible signposts of giant planet formation. The young star HD142527 hosts a massive protoplanetary disk with a large cavity that extends up to 140 AU from the ...
    • A co survey in planet-forming disks: characterizing the gas content in the epoch of planet formation 

      Hales, A.; De Gregorio Monsalvo, Itziar; Montesinos, B.; Casassus Montero, Simón; Dent, William R. F.; Dougados, Catherine; Eiroa, C.; Hughes, A.M.; Garay Brignardello, Guido; Mardones Pérez, Diego; Ménard, Francois; Palau, Aina; Pérez, Sebastián; Phillips, N.; Torrelles, J. M.; Wilner, D. (The American Astronomical Society., 2014-07-31)
      We carried out a 12CO(3-2) survey of 52 southern stars with a wide range of IR excesses (L IR/L *) using the single-dish telescopes APEX and ASTE. The main aims were (1) to characterize the evolution of molecular gas in ...
    • CO(6−5) and [C i](2−1) pointed observations of five protoplanetary disks: Warm gas in HD 142527 

      Casassus Montero, Simón; Hales, A.; De Gregorio Monsalvo, Itziar; Dent, B.; Belloche, A.; Güsten, R.; Ménard, Francois; Hughes, A.M.; Wilner, D.; Salinas, V. (EDP Sciences, 2013-05)
      Context. The molecular gas in protoplanetary disks can be traced with single-dish instruments in low J rotational lines of CO, in systems clear of coincident extended emission. Other rotational lines of CO also sample the ...
    • A Compact Concentration of Large Grains in the HD 142527 Protoplanetary Dust Trap 

      Casassus Montero, Simón; Wright, Chris; Marino, Sebastian; Maddison, Sarah; Wootten, Al; Roman, Pablo; Pérez, Sebastian; Pinilla, Paola; Wyatt, Mark; Moral, Victor; Ménard, Francois; Christiaens, Valentin; Cieza, Lucas; Van der Plas, Gerrit (The American Astronomical Society, 2015-10-20)
      A pathway to the formation of planetesimals, and eventually giant planets, may occur in concentrations of dust grains trapped in pressure maxima. Dramatic crescent-shaped dust concentrations have been seen in recent ...
    • A compact concentration of large grains in the HD 142527 protoplanetary dust trap 

      Casassus Montero, Simón; Wright, Chris; Marino Estay, Sebastián; Maddison, Sarah T.; Wootten, Al; Román Asenjo, Pablo; Pérez, Sebastián; Pinilla, Paola; Wyatt, Mark; Moral, Víctor; Ménard, Francois; Christiaens, Valentín; Cieza, Lucas; Van der Plas, Gerrit (IOP Publishing, 2015)
      A pathway to the formation of planetesimals, and eventually giant planets, may occur in concentrations of dust grains trapped in pressure maxima. Dramatic crescent-shaped dust concentrations have been seen in recent radio ...