DOCSLIB.ORG

Dge, UK) (ESO) (Reipurth/HST/NASA) ESA Neii X-Raysshocks from Against ISM Young Stellar Objects Shock Temperature and Their Impact on the Stellar Environment

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Dge, UK) (ESO) (Reipurth/HST/NASA) ESA Neii X-Raysshocks from Against ISM Young Stellar Objects Shock Temperature and Their Impact on the Stellar Environment X -Ray Jets from Young Stars Manuel Güdel University of Vienna HH34 HH111 Herbig-Haro Objects 100-400 km s-1 Outline • Herbig-Haro Objects • Inner Jets Manuel Güdel ETH• CoolingZürich Protostar Switzerland • Heating Manuel Güdel (University of Vienna), Barbara Ercolano (Munich, Germany), • Conclusions James Owen (Cambridge, UK) (ESO) (Reipurth/HST/NASA) ESA NeII X-RaysShocks from against ISM Young Stellar Objects Shock temperature and their Impact on the Stellar Environment (Raga et al. 2002) requires a few 100 km s-1: OK Luminosity for radiative or non-radiative shock: Manuel Güdel ETH Zürich Switzerland (Raga et al. 2002) typically works OK (L ≈ 1029-31 erg s-1). Manuel Güdel (University Xof Vies Owen (Cambridge, UK) 6 29 -1 HH 2 (Orion): at bow shock of HH object, 10 K, LX ≈ 5x10 erg s V = 200 km s-1 shock HST required for heating measured motion: 230 km s-1 (Pravdo et al. 2001) 30 -1 HH210 (Orion): T = 0.8 MK in fastest HH feature, LX ≈ 10 erg s : -1 V = 170-240 km s required shock observed bow-shock velocity 133-425 km s-1 X-rays HST [SII] (Grosso et al. 2006) HH 80/81 (from very luminous source) 6 31 -1 1.5x10 K, LX ≈ 4.5x10 erg s -1 Vshock = 320 km s required some optical features are much faster (600-1400 km s-1) (Pravdo et al. 2004; contours: HST H) X opt (HST; NASA/ESA) X Cepheus A East & West: HH168 X 6.4x106 K, L ≈ 1.7x1030 erg s-1 H X X-rays behind Hα: cooling post-shock gas? -1 Vshock = 280-680 km s sufficient ~consistent with optical line width in some places (200-600 km s-1) (Pravdo et al. 2005, Schneider et al. 2009) [OI] (Dougados et al. 2000) DG Tau X-Rays (Güdel et al. 2005/08)) X-rays located close to jet base: Internal shocks, or collimation shocks? 5” L1551 IRS5, binary protostar (Favata et al. 2002, Bally et al. 2003) Jet Base? L1551 IRS 5 Star absorbed, inner jet X-ray strong • Cooling jet due to expansion • standing structure at 0.5-1” (Schneider+ 2011) 3 spectra over 1 week Spectroscopic X-Ray Jets DG Tau soft/cool: hard/hot: variable hard/hotconstant high NH low NH >> NH(AV) ? (Güdel et al. 2010) Coronal (hard) emission absorbed by dust-depleted accretion flows with 22 -2 NH > 10 cm Extreme case: edge-on Sz 102 Spectrum very soft, T = 2.1 MK star absorbed, see only jet? ESA 0.3” Chandra ACIS-S image, soft band (0.3-1.5 keV) T = 1.8-3.3 MK -1 vshock = 350-470 km s Deconvolution of SER-treated ACIS data (Güdel+ 2012) 1pixel = 0.0615” 0.15” (33 AU along jet) 2-8 keV 0.3-1.5 keV T = 3.8 MK -1 vshock = 500 km s Offset in 2010 approx. identical to 2005/06 (Schneider et al.: POSTER P47): standing structure; collimation region! Complete picture of DG Tau X-ray jet filling factor f Radiative Cooling V DG Tau: EM = 1.39x1052 cm-3 f = 3.5x10-5 43 -3 6 -3 V = 1.77x10 cm ne = 4.8x10 cm 6 T = 3.7x10 K τ = 0.6 yr 29 -1 LX = 1.8x10 erg s IRS 5: EM = 8.0x1051 cm-3 f = 1.23x10-5 45 -3 5 -3 V = 5x10 cm ne = 3.6x10 cm 6 T = 7.0x10 K τ = 15 yr 28 -1 LX = 8.0x10 erg s DG Tau 0.35” (Dougados et al. 2008) half opening angle for DG Tau ≈ 10 deg (Agra-Amboage+ 2011: possibly smaller) Cooling of inner source including expansion initial radius: 0.1” half opening: 10 deg DG Tau 6 -3 Requirement: Cooling time ~0.6 yrs: n0 > 10 cm L1551 IRS5 (Schneider et al. 2011) Pressure in the Plasma: Stationary Source (Lavalley-Fouquet et al. 2000) optical n ≈ 106 cm-3 T ≈ 104 K nT = 1010 K cm-3 DG Tau 6 -3 6 13 -3 X-ray ne = 4.8x10 cm T ≈ 3.7 x10 K nT = 1.8x10 K cm (Itoh et al. 2000) optical n ≈ 106 cm-3 T ≈ 104 K nT = 1010 K cm-3 IRS 5 5 -3 6 12 -3 X-ray ne = 3.6x10 cm T ≈ 7 x10 K nT = 2.5x10 K cm Hot gas contributes to jet expansion if not located at surface of jet or confined by magnetic fields Origin of X-Ray Sources X-ray shocks in collimation region X-ray scattering Colliding winds/jets from the two components (Bally et al. 2003) Rhodos, 10 July 2008 NeII X-Rays fromShocks Young Stellar Objects and their Impact on the For high-T plasma close to star (L1551 IRS5, DG Tau) measured shock Stellar speeds 50 -100Environment km/s (Agra-Amboage et al. 2009, Lavalley-Fouquet et al. 2000) Even bulk flow speeds often < 300 km s-1 But then, shock temperatures Manuel Güdel ETH Zürich Switzerland (Raga et al. 2002) too low. Manuel Güdel (University of Vies Owen (Cambridge, UK) Plasma Mass Loss Rate A DG Tau: radiative heating dominates in center d radiative decay time cooling distance emission measure v (Agra-Amboage+ 2011) Small amount of high-velocity gas that has escaped detection in the optical? (Günther et al. 2009) NeIIPulsed jetsX -Rays from X- rays density • Periodically ejected Young blobs Stellar Objects • Random velocity and their Impact on the Collisions between blobs Stellar Environment and environment: knots Depending on shocks, chains of X-ray knots especially in low-density jets mostly at jet base Manuel Güdel ETH Zürich Higher ejection rate Switzerland higher LX Manuel Güdel (University of Vienna), Barbara Ercolano (Munich, Germany), James Owen (Cambridge, UK) (Bonito et al. 2010) density X-rays density Diamond shock at nozzle, 1500 km s-1 8 MK (Bonito et al. 2011 for L1551 IRS5) Reconnection (Montmerle et al. 2000): Winding up star-disk fields Antiparallel fields Heating and Reconnection Ejection of hot plasmoids Further shock heating Jets? (Hayashi et al. 1996) Photoevaporation by X-Ray Jets? Mass loss rate absorbed star from DG Tau disk jet dominated by jet irradiation at r > 22 AU X (Owen et al. in prep.) …although this wind does not compete with accretion: -10 -1 star: dM/dt ≈ 3x10 M yr -10 -1 jet: dM/dt ≈ 7x10 M yr HH OBJECTS: HH81 ç√HH168 -Cep A HH210 HH2 ç√ JETS: L1551 ç√ DG Tau IRS5 Z CMa HD 163296 OMC-3 RY Tau “SPECTROSCOPIC X-RAY JETS”: DG Tau GV Tau DP Tau HN Tau Sz 102 Beehive NeII Conclusions • X-rays found in protostellar and T Tauri jets from the base (collimation region?) to distant Herbig-Haro objects Manuel Güdel • Plasma close ETHto stars: Zürich high densities in standing structure Switzerland Manuel • GüdelHeating: (University shocks or magnetic? of Vienna), Barbara• ImportantErcolano influence (Munich, on protoplanetary Germany), disks: James heating, Owen ionisation, (Cambridge, chemistry, UK) photoevaporation NeII X-Rays from Young Stellar Objects and their Impact on the Stellar Environment END Manuel Güdel ETH Zürich Switzerland Manuel Güdel (University of Vienna), Barbara Ercolano (Munich, Germany), James Owen (Cambridge, UK) ESA .
Load more

Recommended publications
  • Open Research Online Oro.Open.Ac.Uk
    Open Research Online The Open University’s repository of research publications and other research outputs What are the hot R Coronae Borealis stars? Journal Item How to cite: De Marco, Orsola; Clayton, Geoffrey C.; Herwig, F.; Pollacco, D. L.; Clark, J. S. and Kilkenny, David (2002). What are the hot R Coronae Borealis stars? Astronomical Journal, 123(6) pp. 3387–3408. For guidance on citations see FAQs. c 2002 The American Astronomical Society Version: [not recorded] Link(s) to article on publisher’s website: http://dx.doi.org/doi:10.1086/340569 http://www.iop.org/EJ/abstract/1538-3881/123/6/3387 Copyright and Moral Rights for the articles on this site are retained by the individual authors and/or other copyright owners. For more information on Open Research Online’s data policy on reuse of materials please consult the policies page. oro.open.ac.uk The Astronomical Journal, 123:3370–3379, 2002 June # 2002. The American Astronomical Society. All rights reserved. Printed in U.S.A. EXTENDED NEAR-INFRARED EMISSION FROM CANDIDATE PROTOSTARS IN THE TAURUS-AURIGA MOLECULAR CLOUD Shinae Park Department of Physics, 366 Le Conte Hall, University of California, Berkeley, Berkeley, CA 94720-7300 and Scott J. Kenyon Smithsonian Astrophysical Observatory, 60 Garden Street, Cambridge, MA 02138 Received 2001 December 17; accepted 2002 February 28 ABSTRACT We describe near-IR imaging data for a sample of 23 Class I sources in the Taurus-Auriga dark clouds. Combining our data with previous photometry, we detect brightness variations of 0.1–0.5 mag in many sources. The near-IR morphologies are consistent with millimeter continuum measurements.
    [Show full text]
  • The XMM-Newton Extended Survey of the Taurus Molecular Cloud (XEST),
    A&A 468, 353–377 (2007) Astronomy DOI: 10.1051/0004-6361:20065724 & c ESO 2007 Astrophysics The XMM-Newton extended survey of the Taurus molecular cloud Special feature The XMM-Newton extended survey of the Taurus molecular cloud (XEST), M. Güdel1, K. R. Briggs1, K. Arzner1, M. Audard2,, J. Bouvier3, E. D. Feigelson4, E. Franciosini5, A. Glauser1, N. Grosso3, G. Micela5, J.-L. Monin3, T. Montmerle3, D. L. Padgett6, F. Palla7, I. Pillitteri8, L. Rebull6, L. Scelsi8, B. Silva9,10, S. L. Skinner11, B. Stelzer5, and A. Telleschi1 1 Paul Scherrer Institut, Würenlingen and Villigen, 5232 Villigen PSI, Switzerland e-mail: [email protected] 2 Columbia Astrophysics Laboratory, Mail Code 5247, 550 West 120th Street, New York, NY 10027, USA 3 Laboratoire d’Astrophysique de Grenoble, Université Joseph Fourier - CNRS, BP 53, 38041 Grenoble Cedex, France 4 Department of Astronomy & Astrophysics, Penn State University, 525 Davey Lab, University Park, PA 16802, USA 5 INAF - Osservatorio Astronomico di Palermo, Piazza del Parlamento 1, 90134 Palermo, Italy 6 Spitzer Science Center, California Institute of Technology, Mail Code 220-6, Pasadena, CA 91125, USA 7 INAF - Osservatorio Astrofisico di Arcetri, Largo Enrico Fermi, 5, 50125 Firenze, Italy 8 Dipartimento di Scienze Fisiche ed Astronomiche, Università di Palermo, Piazza del Parlamento 1, 90134 Palermo, Italy 9 Centro de Astrofísica da Universidade do Porto, Rua das Estrelas, 4150 Porto, Portugal 10 Departamento de Matemática Aplicada, Faculdade de Ciêcias da Universidade do Porto, 4169 Porto, Portugal 11 CASA, 389, University of Colorado, Boulder, CO 80309-0389, USA Received 31 May 2006 / Accepted 5 August 2006 ABSTRACT Context.
    [Show full text]
  • Spitzer Irs Spectra and Envelope Models of Class I Protostars in Taurus E
    The Astrophysical Journal Supplement Series, 176:184Y215, 2008 May A # 2008. The American Astronomical Society. All rights reserved. Printed in U.S.A. SPITZER IRS SPECTRA AND ENVELOPE MODELS OF CLASS I PROTOSTARS IN TAURUS E. Furlan,1,2,3 M. McClure,4 N. Calvet,5 L. Hartmann,5 P. D’Alessio,6 W. J. Forrest,4 D. M. Watson,4 K. I. Uchida,1 B. Sargent,4 J. D. Green,4 and T. L. Herter1 Received 2007 September 11; accepted 2007 November 18 ABSTRACT We present Spitzer Infrared Spectrograph (IRS) spectra of 28 Class I protostars in the Taurus star-forming region. The 5Y36 m spectra reveal excess emission from the inner regions of the envelope and accretion disk surrounding these predecessors of low-mass stars, as well as absorption features due to silicates and ices. Together with shorter and longer wavelength data from the literature, we construct spectral energy distributions and fit envelope models to 22 protostars of our sample, most of which are well constrained due to the availability of the IRS spectra. We infer that the envelopes of the Class I objects in our sample cover a wide range in parameter space, particularly in density and centrifugal radius, implying different initial conditions for the collapse of protostellar cores. Subject headinggs: circumstellar matter — infrared: stars — stars: formation — stars: preYmain-sequence Online material: color figures 1. INTRODUCTION Besides accreting matter, young stars generate powerful out- flows which are launched along magnetic field lines; mass accre- In a now widely accepted evolutionary sequence based on the tion onto the star and mass loss in the form of outflows seem to shape of the spectral energy distribution (SED) in the infrared, be correlated (e.g., Hartigan et al.
    [Show full text]
  • Arxiv:1608.03799V1 [Astro-Ph.SR] 12 Aug 2016 Department of Physics and Astronomy, Graduate School of Science and Engineering, Kagoshima University, 1-21-35
    Draft version November 15, 2018 Preprint typeset using LATEX style AASTeX6 v. 1.0 FORMATION OF THE UNEQUAL-MASS BINARY PROTOSTARS IN L1551 NE BY ROTATIONALLY-DRIVEN FRAGMENTATION Jeremy Lim Department of Physics, The University of Hong Kong, Pokfulam Road, Hong Kong & Laboratory for Space Research, Faculty of Science, The University of Hong Kong, Pokfulam Road, Hong Kong Tomoyuki Hanawa Center for Frontier Science, Chiba University, Inage-ku, Chiba 263-8522, Japan Paul K. H. Yeung Department of Physics, The University of Hong Kong, Pokfulam Road, Hong Kong Shigehisa Takakuwa arXiv:1608.03799v1 [astro-ph.SR] 12 Aug 2016 Department of Physics and Astronomy, Graduate School of Science and Engineering, Kagoshima University, 1-21-35 Korimoto, Kagoshima, Kagoshima, 890-0065, Japan Tomoaki Matsumoto Faculty of Humanity and Environment, Hosei University, Chiyoda-ku, Tokyo 102-8160, Japan 2 Kazuya Saigo Department of Physical Science, Graduate School of Science, Osaka Prefecture University, 1-1 Gakuen-cho, Naka-ku, Sakai, Osaka 599-8531, Japan ABSTRACT We present observations at 7 mm that fully resolve the two circumstellar disks, and a reanalyses of archival observations at 3.5 cm that resolve along their major axes the two ionized jets, of the class I binary protostellar system L1551 NE. We show that the two circumstellar disks are better fit by a shallow inner and steep outer power-law than a truncated power-law. The two disks have very different transition radii between their inner and outer regions of ∼18.6 AU and ∼8.9 AU respectively. Assuming that they are intrinsically circular and geometrically thin, we find that the two circumstellar disks are parallel with each other and orthogonal in projection to their respective ionized jets.
    [Show full text]
  • THE STAR FORMATION NEWSLETTER an Electronic Publication Dedicated to Early Stellar Evolution and Molecular Clouds
    THE STAR FORMATION NEWSLETTER An electronic publication dedicated to early stellar evolution and molecular clouds No. 8 — 1 April 1993 Editor: Bo Reipurth ([email protected]) Abstracts of recently accepted papers Explosive Ejection associated with Star Formation in Orion David Allen1, Michael Burton1,2 1 Anglo-Australian Observatory, PO Box 296, Epping, NSW 2121, Australia 2 School of Physics, University of New South Wales, PO Box 1, Kensington, NSW 2033, Australia Tightly collimated outflows are often found associated with young stars, interacting with the ambient medium to produce shock-excited emission knots known as Herbig-Haro (HH) objects. Of two interpretations for HH objects one, ejection of a dense clump of material, has fallen from favour. More popular interpretations invoke the shocking of stationary blobs by a fast, low-density jet. We report the discovery of a complex of HH objects and associated wakes in the Orion Molecular Cloud—One that requires compact knots of material to have been ejected over a wide opening angle in a seemingly explosive event. Accepted by Nature Modeling of IR Emission of Interstellar Clouds J.P. Bernard1,2, F. Boulanger1,3 and J.L. Puget1 1 IAS, bat 120, Campus d’Orsay, 91405 Orsay CEDEX, France 2 Caltech 320-47, Pasadena CA 91125, U.S.A. 3 IPAC, Caltech 100-22, Pasadena CA 91125, U.S.A. A numerical model was developed to compute the penetration of heating radiation inside molecular clouds and the resulting IR emission of dust when thermal fluctuations of small dust particles is considered. It has been used to investigate physical conditions of some selected clouds heated either by the galactic diffuse Inter Stellar Radiation Field (ISRF) or receiving radiation from nearby young stars.
    [Show full text]
  • Arxiv:0706.2206V1 [Astro-Ph] 14 Jun 2007 1983; Beichman Et Al
    Accepted to the Astrophysical Journal Supplemental Series Preprint typeset using LATEX style emulateapj v. 08/22/09 A CASE STUDY OF LOW-MASS STAR FORMATION Jonathan J. Swift Institute for Astronomy, 2680 Woodlawn Dr., Honolulu, HI 96822-1897: [email protected] William J. Welch Department of Astronomy and Radio Astronomy Laboratory, University of California, 601 Campbell Hall, Berkeley, CA 94720-3411 Accepted to the Astrophysical Journal Supplemental Series ABSTRACT This article synthesizes observational data from an extensive program aimed toward a comprehensive understanding of star formation in a low-mass star-forming molecular cloud. New observations and published data spanning from the centimeter wave band to the near infrared reveal the high and low density molecular gas, dust, and pre-main sequence stars in L1551. The total cloud mass of ∼ 160 M contained within a 0.9 pc has a dynamical timescale, tdyn = 1:1 Myr. Thirty-five pre-main sequence stars with masses from ∼ 0:1 to 1.5 M are selected to be members of the L1551 association constituting a total of 22 ± 5 M of stellar mass. The observed star formation efficiency, SFE = 12%, while the total efficiency, SFEtot, is estimated to fall between 9 and 15%. L1551 appears to have been forming stars for several tdyn with the rate of star formation increas- ing with time. Star formation has likely progressed from east to west, and there is clear evidence that another star or stellar system will form in the high column density region to the northwest of L1551 IRS5. High-resolution, wide-field maps of L1551 in CO isotopologue emission display the structure of the molecular cloud at 1600 AU physical resolution.
    [Show full text]
  • THE STAR FORMATION NEWSLETTER an Electronic Publication Dedicated to Early Stellar Evolution and Molecular Clouds
    THE STAR FORMATION NEWSLETTER An electronic publication dedicated to early stellar evolution and molecular clouds No. 12 — 1 August 1993 Editor: Bo Reipurth ([email protected]) Abstracts of recently accepted papers An Alternative to Unseen Companions to T Tauri Stars Alan P. Boss1 and Harold W. Yorke2 1 DTM, Carnegie Institution of Washington, 5241 Broad Branch Road, NW, Washington, DC 20015, USA 2 Institut f¨ur Astronomie und Astrophysik, Universit¨atW¨urzburg, am Hubland, D-8700 W¨urzburg, FRG Emission at infrared to millimeter wavelengths from the prototypical pre–main-sequence star T Tauri is consistent with the existence of a low mass circumstellar disk around T Tauri. T Tauri’s spectrum can be characterized as flat, but with a significant dip at mid-infrared wavelengths. Mid-infrared dips can result from gaps in the circumstellar disk, and such gaps are thought to imply the existence of unseen companions which produce the gaps through gravitational effects. We show here that mid-infrared dips in T Tauri star spectra may have a more prosaic cause, and may be simply the result of dust grain opacity and the vertical structure of a low mass circumstellar disk without a gap. Accepted by Astrophys. J. Letters Dust Emission Features in 3 µm Spectra of Herbig Ae/Be Stars T.Y. Brooke1, A.T. Tokunaga2 and S.E. Strom3 1 MS 169-237, Jet Propulsion Laboratory, 4800 Oak Grove Dr., Pasadena, CA, 91109 2 Institute for Astronomy, University of Hawaii, 2680 Woodlawn Dr., Honolulu, HI 96822 3 Five College Astronomy Department, University of Massachusetts, Amherst, MA 01002 Low and medium resolution spectra in the 3 µm region were obtained of 24 Herbig Ae/Be stars in a search for organic features from the dust around young stars.
    [Show full text]
  • THE STAR FORMATION NEWSLETTER an Electronic Publication Dedicated to Early Stellar Evolution and Molecular Clouds
    THE STAR FORMATION NEWSLETTER An electronic publication dedicated to early stellar evolution and molecular clouds No. 193 — 13 Jan 2009 Editor: Bo Reipurth ([email protected]) Abstracts of recently accepted papers [O i] sub-arcsecond study of a microjet from an intermediate mass young star: RY Tau V. Agra-Amboage1, C. Dougados1, S. Cabrit2, P.J.V. Garcia3,4,1 and P. Ferruit5 1 Laboratoire d’Astrophysique de l’Observatoire de Grenoble, UMR 5521 du CNRS, 38041 Grenoble C´edex 9, France 2 LERMA, Observatoire de Paris, UMR 8112 du CNRS, 61 Avenue de l’Observatoire, 75014 Paris, France 3 Departamento de Engenharia Fisica,Faculdade de Engenharia,Universidade do Porto, 4200-465 Porto, Portugal 4 Centro de Astrofisica, Universidade do Porto, Porto, Portugal 5 CRAL, Observatoire de Lyon, 9 Av. Charles Andr´e, F-69230 St. Genis Laval, France E-mail contact: Catherine.Dougados at obs.ujf-grenoble.fr High-resolution studies of microjets in T Tauri stars (cTTs) reveal key information on the jet collimation and launching mechanism, but only a handful of systems have been mapped so far. We perform a detailed study of the microjet from the 2 M⊙ young star RY Tau, to investigate the influence of its higher stellar mass and claimed close binarity on jet properties. Spectro-imaging observations of RY Tau were obtained in [O i]λ6300 with resolutions of 0.4′′ and 135 km s−1, using the integral field spectrograph OASIS at the Canada-France-Hawaii Telescope. Deconvolved images reach a resolution of 0.2′′. The blueshifted jet is detected within 2′′ of the central star.
    [Show full text]
  • Searching for Gas Emission Lines in Spitzer Infrared Spectrograph \(IRS
    A&A 528, A22 (2011) Astronomy DOI: 10.1051/0004-6361/201015622 & c ESO 2011 Astrophysics Searching for gas emission lines in Spitzer Infrared Spectrograph (IRS) spectra of young stars in Taurus C. Baldovin-Saavedra1,2, M. Audard1,2, M. Güdel3,L.M.Rebull4,D.L.Padgett4, S. L. Skinner5, A. Carmona1,2,A.M.Glauser6,7, and S. B. Fajardo-Acosta8 1 ISDC Data Centre for Astrophysics, Université de Genève, 16 chemin d’Ecogia, 1290 Versoix, Switzerland e-mail: [email protected] 2 Observatoire Astronomique de l’Université de Genève, 51 chemin de Maillettes, 1290 Sauverny, Switzerland 3 University of Vienna, Department of Astronomy, Türkenschanzstrasse 17, 1180 Vienna, Austria 4 Spitzer Science Center, California Institute of Technology, 220-6 1200 East California Boulevard, CA 91125 Pasadena, USA 5 Center for Astrophysics and Space Astronomy, University of Colorado, CO 80309-0389 Boulder, USA 6 ETH Zürich, 27 Wolfgang-Pauli-Str., 8093 Zürich, Switzerland 7 UK Astronomy Technology Centre, Royal Observatory, Blackford Hill, EH3 9HJ Edinburgh, UK 8 IPAC, California Institute of Technology, 770 South Wilson Avenue, CA 91125 Pasadena, USA Received 19 August 2010 / Accepted 14 January 2011 ABSTRACT Context. Our knowledge of circumstellar disks has traditionally been based on studies of dust. However, gas dominates the disk mass and its study is key to our understanding of accretion, outflows, and ultimately planet formation. The Spitzer Space Telescope provides access to gas emission lines in the mid-infrared, providing crucial new diagnostics of the physical conditions in accretion disks and outflows. Aims. We seek to identify gas emission lines in mid-infrared spectra of 64 pre-main-sequence stars in Taurus.
    [Show full text]
  • Searching for Gas Emission Lines in Spitzer Infrared Spectrograph (IRS
    Astronomy & Astrophysics manuscript no. 15622 c ESO 2018 February 7, 2018 Searching for gas emission lines in Spitzer Infrared Spectrograph (IRS) spectra of young stars in Taurus Baldovin-Saavedra, C.1,2, Audard, M.1,2, G¨udel, M.3, Rebull, L. M.4, Padgett, D. L.4, Skinner, S. L.5, Carmona, A.1,2, Glauser, A. M.6,7, and Fajardo-Acosta, S. B.8 1 ISDC Data Centre for Astrophysics, Universit´ede Gen`eve, 16 Chemin d’Ecogia, CH-1290 Versoix, Switzerland 2 Observatoire Astronomique de l’Universit´ede Gen`eve, 51 Chemin de Maillettes, CH-1290 Sauverny, Switzerland 3 University of Vienna, Department of Astronomy, T¨urkenschanzstrasse 17, A-1180 Vienna, Austria 4 Spitzer Science Center, California Institute of Technology, 220-6 1200 East California Boulevard, Pasadena, CA 91125 USA 5 Center for Astrophysics and Space Astronomy, University of Colorado, Boulder, CO 80309-0389, USA 6 ETH Z¨urich, 27 Wolfgang-Pauli-Str., CH-8093 Z¨urich, Switzerland 7 UK Astronomy Technology Centre, Royal Observatory, Blackford Hill, EH3 9HJ Edinburgh, UK 8 IPAC, California Institute of Technology, 770 South Wilson Avenue, Pasadena, CA 91125, USA Received August 2010; accepted January 2011 ABSTRACT Context. Our knowledge of circumstellar disks has traditionally been based on studies of dust. However, gas dominates the disk mass and its study is key to our understanding of accretion, outflows, and ultimately planet formation. The Spitzer Space Telescope provides access to gas emission lines in the mid-infrared, providing crucial new diagnostics of the physical conditions in accretion disks and outflows. Aims. We seek to identify gas emission lines in mid-infrared spectra of 64 pre-main-sequence stars in Taurus.
    [Show full text]
  • Arxiv:1908.04649V1 [Astro-Ph.SR] 13 Aug 2019 of a Circumstellar Disk) Or from the Inside (In Case of a Depth and the Grain Size Distribution (Birnstiel Et Al
    Draft version August 14, 2019 Typeset using LATEX twocolumn style in AASTeX62 Resolved ALMA continuum image of the circumbinary ring and circumstellar disks in the L1551 IRS 5 system Fernando Cruz-Saenz´ de Miera,1 Agnes´ Kosp´ al,´ 1, 2 Peter´ Abrah´ am,´ 1 Hauyu Baobab Liu,3 and Michihiro Takami3 1Konkoly Observatory, Research Centre for Astronomy and Earth Sciences, Hungarian Academy of Sciences, Konkoly-Thege Mikl´os´ut15-17, 1121 Budapest, Hungary 2Max Planck Institute for Astronomy, K¨onigstuhl17, 69117 Heidelberg, Germany 3Institute of Astronomy and Astrophysics, Academia Sinica, 11F of Astronomy-Mathematics Building, AS/NTU, No.1, Sec. 4, Roosevelt Rd., Taipei 10617, Taiwan, R.O.C. (Accepted August 9, 2019) Submitted to The Astrophysical Journal Letters ABSTRACT L1551 IRS 5 is a FUor-like object located in the Taurus star forming region. We present ALMA 1.3 mm continuum observations using a wide range of baselines. The observations recovered the two circumstellar disks composing the system and, for the first time, resolved the circumbinary ring. We determined the geometry and estimated lower mass limits for the circumstellar disks using simple models. We calculated lower limits for the total mass of both circumstellar disks. After subtracting the two circumstellar disk models from the image, the residuals show a clearly resolved circumbinary ring. Using a radiative transfer model, we show that geometrical effects can explain some of the brightness asymmetries found in the ring. The remaining features are interpreted as enhancements in the dust density. Keywords: stars: pre-main sequence | circumstellar matter | stars: individual(L1551 IRS 5) 1. INTRODUCTION may feed material to circumstellar disks, helping planet Stellar multiplicity is widespread: although the mul- formation (Dutrey et al.
    [Show full text]
  • From Stars to Planets II - Participants 1 Akimkin, Vitaly (Inst
    From Stars to Planets II - Participants 1 Akimkin, Vitaly (Inst. of Astronomy, Russian Academy of Sciences) - Early evolution of self-gravitating circumstellar disks with a dust component 2 Andersen, Morten (Gemini Obs.) - The formation of massive star clusters 3 Angarita Arenas, Yenifer (Leeds) - Pattern Finding in Samples of Spectroscopic Data 4 Bisbas, Thomas (Athens/Koln) - How do the observables of molecular clouds depend on the ISM environmental parameters? 5 Bitsch, Bertram (MPIA) - Formation and composition of super-Earths 6 Bjerkeli, Per (Chalmers) - Resolving star and planet formation with ALMA 7 Booth, Alice (Leeds) - The First Detection of 13C17O in a Protoplanetary Disk: A Robust Tracer of Disk Mass 8 Bosman, Arthur (Leiden) - Probing planet formation and disk substructures in the inner disk 9 Brandeker, Alexis (Stockholm) - Is it raining lava in the evening on the super Earth 55 Cancri e? 10 Cai, Maxwell Xu (Leiden) - Diverse stellar environments result in diverse exoplanet architectures 11 Calcino, Josh (Queensland) - Signatures of an eccentric disc: Dust and gas in IRS48 12 Calcutt, Hannah (Chalmers) - From low-mass to high-mass: Chemical variability across the Galaxy 13 Cao, Yue (Nanjing) - Striking resemblance between the mass spectrum of sub-pc clumps and the initial mass function 14 Carpenter, Vincent (MPIA) - Simulations of the Onset of Collective Motion of Sedimenting Particles 15 Chabrier, Gilles (CRAL, ENS-Lyon) - Exploring new fundamental physical mechanisms in star and planet formation and evolution 16 Chen, Lei
    [Show full text]