Browsing by Subject "Circumstellar matter"

Now showing items 21-40 of 50

    • New constraints on the disk characteristics and companion candidates around T Chamaeleontis with VLT/SPHERE 
      Pohl, A.; Sissa, E.; Langlois, M.; Zurlo, A. (EDP Sciences, 2017)
      Context. The transition disk around the T Tauri star T Cha possesses a large gap, making it a prime target for high-resolution imaging in the context of planet formation. Aims. We aim to find signs of disk evolutionary ...
    • Nonazimuthal linear polarization in protoplanetary disks 
      Canovas, H.; Ménard, Francois; Boer, J. de; Pinte, Christophe; Avenhaus, H.; Schreiber, M. (EDP Sciences, 2015)
      Several studies discussing imaging polarimetry observations of protoplanetary disks use the so-called radial Stokes parameters Q and U to discuss the results. This approach has the advantage of providing a direct measure ...
    • Observations of edge-on protoplanetary disks with ALMA I. Results from continuum data 
      Villenave, M.; Menard, F.; Dent, W. R. F.; Duchene, G.; Stapelfeldt, K. R.; Benisty, M.; Boehler, Y.; Van der Plas, G.; Pinte, C.; Telkamp, Z.; Wolff, S.; Flores, C.; Lesur, G.; Louvet, F.; Riols, A.; Dougados, C.; Williams, H.; Padgett, D. (EDP, 2020)
      Aims. We aim to study vertical settling and radial drift of dust in protoplanetary disks from a different perspective: an edge-on view. An estimation of the amplitude of settling and drift is highly relevant to understanding ...
    • On the nature of the tertiary companion to FW Tau: ALMA CO observations and SED modeling 
      Cáceres, Claudio; Hardy, Adam; Schreiber, Matthias R.; Cánovas, Héctor; Cieza, Lucas A.; Williams, Jonathan P.; Hales, Antonio; Pinte, Christophe; Ménard, Francois; Wahhaj, Zahed (IOP Publishing, 2015)
      It is thought that planetary mass companions may form through gravitational disk instabilities or core accretion. Identifying such objects in the process of formation would provide the most direct test for the competing ...
    • On the Source of the Dust Extinction in Type Ia Supernovae and the Discovery of Anomalously Strong Na I Absorption 
      Phillips, M. M.; Simon, Joshua D.; Morrell, Nidia; Burns, Christopher R.; Cox, Nick; Foley, Ryan J.; Karakas, Amanda; Patat, F.; Sternberg, A.; Williams, R.; Gal Yam, Avishay; Hsiao, Eric; Leonard, D.; Persson, Sven; Stritzinger, Maximilian; Thompson, I.; Campillay, Abdo; Contreras, Carlos; Folatelli, Gastón; Freedman, Wendy L.; Hamuy Wackenhut, Mario; Roth, Miguel; Shields, Gregory; Suntzeff, Nicholas B.; Chomiuk, Laura; Ivans, Inese; Madore, Barry; Penprase, B.; Perley, Daniel; Pignata Libralato, Giuliano; Preston, G.; Soderberg, Alicia (The American Astronomical Society, 2013-11-10)
      High-dispersion observations of the Na i D λλ5890, 5896 and K i λλ7665, 7699 interstellar lines, and the diffuse interstellar band at 5780 Å in the spectra of 32 Type Ia supernovae are used as an independent means of ...
    • Optical Imaging Polarimetry of the LkCa 15 protoplanetary Disk with Sphere Zimpol 
      Thalmann, C.; Mulders, G. D.; Janson, M.; Olofsson, J.; Benisty, Myriam; Avenhaus, H.; Quanz, S. P.; Schmid, H. M.; Henning, Thomas; Buenzli, E.; Ménard, Francois; Carson, J. C.; Garufi, A.; Messina, S.; Dominik, C.; Leisenring, J.; Chauvin, G.; Meyer, M. R. (IOP Publishing, 2015)
      We present the first optical (590-890 nm) imaging polarimetry observations of the pre-transitional protoplanetary disk around the young solar analog LkCa 15, addressing a number of open questions raised by previous studies. ...
    • Precession and accretion in circumbinary discs: the case of HD 104237 
      Dunhill, A. C.; Cuadra, J.; Dougados, Catherine (Royal Astronomical Society, 2015)
      We present the results of smoothed particle hydrodynamics (SPH) simulations of the disc around the young, eccentric stellar binary HD 104237. We find that the binary clears out a large cavity in the disc, driving a ...
    • Probing protoplanetary disk evolution in the Chamaeleon II region 
      Villenave, M.; Ménard, F.; Dent, W. R. F.; Benisty, Myriam; Van der Plas, G.; Williams, J. P.; Ansdell, M.; Ribas, A.; Cáceres, C.; Cánovas, H.; Cieza, L.; Hales, A.; Kamp, I.; Pinte, C.; Principe, D. A.; Schreiber, M. R. (EDP Sciences, 2021)
      Context. Characterizing the evolution of protoplanetary disks is necessary to improve our understanding of planet formation. Constraints on both dust and gas are needed to determine the dominant disk dissipation ...
    • Resolving asymmetries along the pulsation cycle of the Mira star X Hydrae 
      Haubois, X.; Wittkowski, M.; Perrin, G.; Kervella, Pierre; Mérand, A.; Thiébaut, E.; Ridgway, S.; Ireland, M.; Scholz, M. (EDP Sciences, 2015)
      Context. The mass-loss process in Mira stars probably occurs in an asymmetric way where dust can form in inhomogeneous circumstellar molecular clumps. Following asymmetries along the pulsation cycle can give us clues about ...
    • Resolving structure of the disc around HD100546 at 7 mm with ATCA 
      Wright, C. M.; Maddison, S. T.; Wilner, D. J.; Burton, M. G.; Lommen, D.; Dishoeck, E. F. van; Pinilla, P.; Bourke, T. L.; Ménard, Francois; Walsh, C. (Royal Astronomical Society, 2015)
      There is much evidence that planet formation is occurring in the disc around the Herbig Be star HD100546. To learn more about the processes occurring in this disc, we conducted high-resolution imaging at 43/45 GHz with the ...
    • Resolving the planetesimal belt of HR 8799 with ALMA 
      Booth, Mark; Jordán, Andrés; Casassus Montero, Simón; Hales, Antonio; Dent, William R. F.; Faramaz, Virginie; Matra, Luca; Barkats, Denis; Brahm, Rafael; Cuadra, Jorge (Oxford University Press, 2016)
      The star HR 8799 hosts one of the largest known debris discs and at least four giant planets. Previous observations have found evidence for a warm belt within the orbits of the planets, a cold planetesimal belt beyond their ...
    • SALT observations of the chromospheric activity of transiting planet hosts: Mass-loss and star-planet interactions 
      Staab, D.; Haswell, C. A.; Smith, Gareth D.; Fossati, L.; Barnes, J. R.; Busuttil, R.; Jenkins, James Stewart (Oxford University, 2017)
      We measured the chromospheric activity of the four hot Jupiter hosts WASP-43, WASP-51/HAT-P-30, WASP-72 and WASP-103 to search for anomalous values caused by the close-in companions. The Mount Wilson CaIIH&KS-index was ...
    • Searching for light echoes due to circumstellar matter in SNe la Spectra 
      Marino, Sebastián; González Gaitán, Santiago; Förster, Francisco; Folatelli, Gastón; Hamuy Wackenhut, Mario; Hsiao, Eric (The American Astronomical Society, 2015)
      We present an analytical model for light echoes (LEs) coming from circumstellar material (CSM) around Type Ia Supernovae (SNe Ia). Using this model we find two spectral signatures at 4100 angstrom and 6200 angstrom that ...
    • Size and structures of disks around very low mass stars in the taurus star-forming region 
      Kurtovic, N. T.; Pinilla, P.; Long, F.; Benisty, Myriam; Manara, C. F.; Natta, A.; Pascucci, I.; Ricci, L.; Scholz, A.; Testi, L. (EDP Sciences, 2021)
      Context. The discovery of giant planets orbiting very low mass stars (VLMS) and the recent observed substructures in disks around VLMS is challenging planet formation models. Specifically, radial drift of dust particles ...
    • SN 2011A: A Low-Luminosity Interacting Transient With A Double Plateau And Strong Sodium Absorption 
      De Jaeger, Thomas; Anderson, J. P.; Pignata Libralato, Giuliano; Hamuy Wackenhut, Mario; Kankare, E.; Stritzinger, M. D.; Benetti, S.; Bufano, Filomena; Elias-Rosa, Nancy; Folatelli, Gastón; Forster, Francisco; González Gaitán, Santiago; Gutiérrez, C. P.; Inserra, C.; Kotak, R.; Lira Teillery, Paulina; Morrell, N.; Taddia, F.; Tomasella, L. (IOP Publisihing, 2015)
      We present optical photometry and spectroscopy of the optical transient SN 2011A. Our data span 140 days after discovery including BVRI u'g'r'i'z' photometry and 11 epochs of optical spectroscopy. Originally classified as ...
    • Sparse aperture masking observations of the FL Cha pre-transitional disk 
      Cieza, Lucas A.; Lacour, Sylvestre; Schreiber, Matthias R.; Casassus Montero, Simón; Jordán, Andrés; Mathews, Geoffrey S.; Cánovas, Héctor; Ménard, Francois; Kraus, Adam L.; Pérez, Sebastián; Tuthill, Peter; Ireland, Michael J. (The American Astronomical Society, 2013)
      We present deep Sparse Aperture Masking (SAM) observations obtained with the ESO Very Large Telescope of the pre-transitional disk object FL Cha (SpT = K8, d = 160 pc), the disk of which is known to have a wide optically thin ...
    • Spiral arms in the protoplanetary disc HD100453 detected with ALMA: evidence for binary-disc interaction ... 
      Rosotti, G. P.; Benisty, M.; Juhasz, A.; Teague, R.; Clarke, C.; Dominik, C.; Dullemond, C. P.; Klaassen, P. D.; Matra, L.; Stolker, T. (Oxford Univ Press, 2020)
      Scattered light high-resolution imaging of the protoplanetary disc orbiting HD100453 shows two symmetric spiral arms, possibly launched by an external stellar companion. In this paper, we present new, sensitive high-resolution ...
    • Submilliarcsecond optical interferometry of the high-mass X-Ray binary BP Cru with VLTI/GRAVITY 
      Waisberg, I.; Dexter, J.; Pfuhl, O.; Kervella, P. (IOP Publishing Ltd, 2017)
      We observe the high-mass X-ray binary (HMXB) BP Cru using interferometry in the near-infrared K band with VLTI/GRAVITY. Continuum visibilities are at most partially resolved, consistent with the predicted size of the ...
    • The ALMA early science view of FUor/EXor objects - V. Continuum disc masses and sizes 
      Cieza, Lucas A.; Ruiz Rodriguez, Dary; Pérez, Sebastián; Casassus Montero, Simón; Williams, Jonathan P.; Zurlo, Alice; Principe, David A.; Hales, Antonio; Prieto, Jose L.; Tobin, John J.; Zhu, Zhaohuan; Marino, Sebastián (Oxford University Press, 2018)
      Low-mass stars build a significant fraction of their total mass during short outbursts of enhanced accretion known as FUor and EXor outbursts. FUor objects are characterized by a sudden brightening of similar to 5 mag at ...
    • The Circumstellar Disk and Asymmetric Outflow of the EX Lup Outburst System 
      Hales, A. S.; Pérez, S.; Saito, M.; Pinte, C.; Knee, L. B. G.; De Gregorio Monsalvo, Itziar; Dent, B.; López, C.; Plunkett, A.; Cortés, P.; Corder, S.; Cieza, L. (Institute of Physics Publishing, 2018)
      We present Atacama Large Millimeter/submillimeter Array (ALMA) observations at 0farcs3 resolution of EX Lup, the prototype of the EXor class of outbursting pre-main-sequence stars. The circumstellar disk of EX Lup is ...