Browsing by Author "Casassus Montero, Simón"

Now showing items 1-20 of 41

    • 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 ...
    • ALMA Observations of Elias 2-24: A Protoplanetary Disk with Multiple Gaps in the Ophiuchus Molecular Cloud 
      Cieza, Lucas; Casassus Montero, Simón; Pérez, Sebastián; Hales, Antonio; Cárcamo, Miguel; Ansdell, Megan; Avenhaus, Henning; Bayo, Amelia; Bertrang, Gesa; Cánovas, Hector; Christiaens, Valentin; Dent, William; Ferrero, Gabriel; Gamen, Roberto; Olofsson, Johan; Orcajo, Santiago; Osses, Axel; Peña-Ramirez, Karla; Principe, David; Ruíz-Rodríguez, Dary; Schreiber, Matthias; Van der Plas, Gerrit; Williams, Jonathan; Zurlo, Alice (Institute of Physics Publishing, 2017)
      We present ALMA 1.3 mm continuum observations at 0."2 (25 au) resolution of Elias 2-24, one of the largest andbrightest protoplanetary disks in the Ophiuchus Molecular Cloud, and we report the presence of three partiallyresolved ...
    • 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 ...
    • 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 ... 
      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)
      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 ...
    • 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 ...
    • Constraints on free–free emission from anomalous microwave emission sources in the perseus molecular cloud 
      Tibbs, C.; Paladini, R.; Dickinson, C.; Mason, B.S.; Casassus Montero, Simón; Cleary, K.; Davies, R.D.; Davis, R.J.; Watson, R.A. (The American Astronomical Society, 2013-06-20)
      We present observations performed with the Green Bank Telescope at 1.4 and 5 GHz of three strips coincident with the anomalous microwave emission features previously identified in the Perseus molecular cloud at 33 GHz ...
    • Disks around T tauri stars with SPHERE (DARTTS-S). I. SPHERE/IRDIS polarimetric imaging of eight prominent ... 
      Avenhaus, Henning; Quanz, Sascha P.; Garufi, Antonio; Pérez, Sebastián; Casassus Montero, Simón; Pinte, Christophe; Bertrang, Gesa H. -M; Cáceres, Claudio; Benisty, Myriam; Dominik, Carsten (IOP Publishing, 2018)
      We present the first part of our Disks ARound T Tauri Stars with SPHERE (DARTTS-S) survey: observations of eight T Tauri stars that were selected based on their strong (sub)millimeter excesses using SPHERE/IRDIS polarimetric ...
    • Dust-correlated centimetre-wave radiation from the M78 reflection nebula 
      Castellanos, Pablo; Casassus Montero, Simón; Dickinson, Clive; Vidal, Matías; Paladini, Roberta; Cleary, Kieran; Davies, Rodney D.; Davis, Richard J.; White, Glenn J.; Taylor, Angela C. (WILEY-BLACKWELL, 2011-02)
      An anomalous radio continuum component at cm-wavelengths has been observed in various sources, including dark clouds. This continuum component represents a new property of the ISM. In this work we focus on one particular ...
    • Dust-correlated cm wavelength continuum emission from translucent clouds ζ Oph and LDN 1780 
      Vidal, M.; Casassus Montero, Simón; Dickinson, C.; Witt, A. N.; Castellanos, P.; Davies, R. D.; Davis, R. J.; Cabrera, G.; Cleary, K.; Allison, J. R.; Bond, J. R.; Bronfman Aguiló, Leonardo; Bustos, R.; Jones, M. E.; Paladini, R.; Pearson, T. J.; Readhead, A. C. S.; Reeves, R.; Sievers, J. L.; Taylor, A. C. (2011)
      The diffuse cm wave IR-correlated signal, the ‘anomalous’ CMB foreground, is thought to arise in the dust in cirrus clouds.We present Cosmic Background Imager (CBI) cm wave data of two translucent clouds, ζ Oph and LDN ...
    • Gas Inside the 97 AU Cavity around the Transition Disk Sz 91 
      Canovas, H.; Schreiber, M. R.; Cáceres, C.; Ménard, Francois; Pinte, Christophe; Mathews, G.; Cieza, L.; Casassus Montero, Simón; Hales, A.; Williams, J. P.; Román, P.; Hardy, A. (The American Astronomical Society, 2015-05-20)
      We present ALMA (Cycle 0) band 6 and band 3 observations of the transition disk Sz 91. The disk inclination and position angle are determined to be i = 49◦ . 5 ± 3◦ . 5°and PA = 18◦ . 2 ± 3◦ . 5 and the dusty and ...
    • Hydrodynamical simulations of dust traps in protoplanetary disks 
      Barraza Alfaro, Marcelo Fernando (Universidad de Chile, 2018)
      Las teorías actuales de formación planetaria concuerdan que los planetas se forman dentro de discos de gas y polvo alrededor de una estrella jóven. Sin embargo, no es claro cuál es el mecanismo detrás de la formación ...
    • Hyperfine splitting of [Al VI] 3.66 mu m and the Al isotopic ratio in NGC 6302 
      Casassus Montero, Simón; Storey, P. J.; Barlow, M. J.; Roche, P. F. (WILEY-BLACKWELL, 2005-06-01)
      The core of planetary nebula NGC 6302 is filled with high-excitation photoionized gas at low expansion velocities. It represents a unique astrophysical situation in which to search for hyperfine structure (HFS) in coronal ...
    • Imaging of interactions between circumstellar disks and extrasolar planets 
      Christiaens, Valentín André (Universidad de Chile, 2018)
      Se necesitan observaciones para restringir los mecanismos involucrados en el proceso de formación de planetas. Los discos circunestelares ricos en gas y polvo, llamados discos protoplanetarios, son el lugar esperado de ...
    • Improving signal-to-noise in the direct imaging of exoplanets and circumstellar disks with MLOCI 
      Wahhaj, Zahed; Cieza, Lucas; Mawet, Dimitri; Yang, Bin; Canovas, Héctor; Boer, Jozua de; Casassus Montero, Simón; Ménard, Francois; Schreiber, Matthias; Liu, Michael; Biller, Beth; Nielsen, Eric; Hayward, Thomas (EDP Sciences, 2015)
      We present a new algorithm designed to improve the signal-to-noise ratio (S/N) of point and extended source detections around bright stars in direct imaging data. One of our innovations is that we insert simulated point ...
    • The inner environment of Z Canis Majoris: High-contrast imaging polarimetry with NaCo 
      Canovas, H.; Pérez, Sebastián; Dougados, C.; de Boer, J.; Ménard, Francois; Casassus Montero, Simón; Schreiber, M. R.; Cieza, L. A.; Caceres, C.; Girard, J. H. (EDP SCIENCES, 2015)
      Context. Z CMa is a binary composed of an embedded Herbig Be and an FU Ori class star separated by ∼100 au. Observational evidence indicates a complex environment in which each star has a circumstellar disk and drives a ...