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Dust and Gas in the Disk of Hl Tauri: Surface Density, Dust Settling, and Dust-To-Gas Ratio C
The Astrophysical Journal, 816:25 (12pp), 2016 January 1 doi:10.3847/0004-637X/816/1/25 © 2016. The American Astronomical Society. All rights reserved. DUST AND GAS IN THE DISK OF HL TAURI: SURFACE DENSITY, DUST SETTLING, AND DUST-TO-GAS RATIO C. Pinte1,2, W. R. F. Dent3, F. Ménard1,2, A. Hales3,4, T. Hill3, P. Cortes3,4, and I. de Gregorio-Monsalvo3 1 UMI-FCA, CNRS/INSU, France (UMI 3386), and Dept. de Astronomía, Universidad de Chile, Santiago, Chile; [email protected] 2 Univ. Grenoble Alpes, IPAG, F-38000 Grenoble, France CNRS, IPAG, F-38000 Grenoble, France 3 Atacama Large Millimeter/Submillimeter Array, Joint ALMA Observatory, Alonso de Córdova 3107, Vitacura 763-0355, Santiago, Chile 4 National Radio Astronomy Observatory, 520 Edgemont Road, Charlottesville, VA 22903-2475, USA Received 2015 March 22; accepted 2015 September 8; published 2015 December 29 ABSTRACT The recent ALMA observations of the disk surrounding HL Tau reveal a very complex dust spatial distribution. We present a radiative transfer model accounting for the observed gaps and bright rings as well as radial changes of the emissivity index. We find that the dust density is depleted by at least a factor of 10 in the main gaps compared to the surrounding rings. Ring masses range from 10–100 M⊕ in dust, and we find that each of the deepest gaps is consistent with the removal of up to 40 M⊕ of dust. If this material has accumulated into rocky bodies, these would be close to the point of runaway gas accretion. -
Condensation of the Solar Nebular
Formation of the Sun-like Stars • Collapse of a portion of a molecular cloud 4.5-4.6 Ga – Star dusts in primitive meteorites provide – Fingerprints of neaby stars that preceded our Sun – Stars like our Sun can form in a large number (hundreds to thousands) and close to each other (0.1 pc or ~0.3 lightyear, much closer than the Sun’s neighbor stars) as seen in the Orion Nebular. – Modern molecular clouds also has circumstellar disks, where planets form. – Gas in the molecular clouds is cold (~4K) and relatively dense (104 atoms/cm3). 1 Formation of the Sun-like Stars • Young stars emits more infrared radiation than a blackbody of the same size –Due to dark (opaque) disks around them. –Such disks are dubbed “proplyds” (proto-planetary disks). • Planets in the solar system orbit the Sun in the same direction and the orbits are roughly coplanar. –Suggests the solar system originated from a disk-shaped region of material referred to as the solar nebular. –An old idea conceived at least 2 centuries ago. –Discovery of proplyds now provide strong support. 2 Formation of the Sun-like Stars • Not clear what triggers the collapse of the densest portion of the cloud (“core”) to form stars. – Sequential ages of stars in close proximity in a molecular cloud suggests that formation and evolution of some stars trigger the formation of additional stars. • Gas around the collapsing core of the molecular cloud is moving – Too much angular momentum binary star – Otherwise, a single protostar called a T Tauri star or a pre-main sequence star. -
Hubbl E Space T El Escope Wfpc2 Imaging of Fs Tauri and Haro 6-5B1 John E.Krist,2 Karl R.Stapelfeldt,3 Christopher J.Burrows,2,4 Gilda E.Ballester,5 John T
THE ASTROPHYSICAL JOURNAL, 501:841È852, 1998 July 10 ( 1998. The American Astronomical Society. All rights reserved. Printed in U.S.A. HUBBL E SPACE T EL ESCOPE WFPC2 IMAGING OF FS TAURI AND HARO 6-5B1 JOHN E.KRIST,2 KARL R.STAPELFELDT,3 CHRISTOPHER J.BURROWS,2,4 GILDA E.BALLESTER,5 JOHN T. CLARKE,5 DAVID CRISP,3 ROBIN W.EVANS,3 JOHN S.GALLAGHER III,6 RICHARD E.GRIFFITHS,7 J. JEFF HESTER,8 JOHN G.HOESSEL,6 JON A.HOLTZMAN,9 JEREMY R.MOULD,10 PAUL A. SCOWEN,8 JOHN T.TRAUGER,3 ALAN M. WATSON,11 AND JAMES A. WESTPHAL12 Received 1997 December 18; accepted 1998 February 16 ABSTRACT We have observed the Ðeld of FS Tauri (Haro 6-5) with the Wide Field Planetary Camera 2 on the Hubble Space Telescope. Centered on Haro 6-5B and adjacent to the nebulous binary system of FS Tauri A there is an extended complex of reÑection nebulosity that includes a di†use, hourglass-shaped structure. H6-5B, the source of a bipolar jet, is not directly visible but appears to illuminate a compact, bipolar nebula which we assume to be a protostellar disk similar to HH 30. The bipolar jet appears twisted, which explains the unusually broad width measured in ground-based images. We present the Ðrst resolved photometry of the FS Tau A components at visual wavelengths. The Ñuxes of the fainter, eastern component are well matched by a 3360 K blackbody with an extinction ofAV \ 8. For the western star, however, any reasonable, reddened blackbody energy distribution underestimates the K-band photometry by over 2 mag. -
Exoplanet.Eu Catalog Page 1 # Name Mass Star Name
exoplanet.eu_catalog # name mass star_name star_distance star_mass OGLE-2016-BLG-1469L b 13.6 OGLE-2016-BLG-1469L 4500.0 0.048 11 Com b 19.4 11 Com 110.6 2.7 11 Oph b 21 11 Oph 145.0 0.0162 11 UMi b 10.5 11 UMi 119.5 1.8 14 And b 5.33 14 And 76.4 2.2 14 Her b 4.64 14 Her 18.1 0.9 16 Cyg B b 1.68 16 Cyg B 21.4 1.01 18 Del b 10.3 18 Del 73.1 2.3 1RXS 1609 b 14 1RXS1609 145.0 0.73 1SWASP J1407 b 20 1SWASP J1407 133.0 0.9 24 Sex b 1.99 24 Sex 74.8 1.54 24 Sex c 0.86 24 Sex 74.8 1.54 2M 0103-55 (AB) b 13 2M 0103-55 (AB) 47.2 0.4 2M 0122-24 b 20 2M 0122-24 36.0 0.4 2M 0219-39 b 13.9 2M 0219-39 39.4 0.11 2M 0441+23 b 7.5 2M 0441+23 140.0 0.02 2M 0746+20 b 30 2M 0746+20 12.2 0.12 2M 1207-39 24 2M 1207-39 52.4 0.025 2M 1207-39 b 4 2M 1207-39 52.4 0.025 2M 1938+46 b 1.9 2M 1938+46 0.6 2M 2140+16 b 20 2M 2140+16 25.0 0.08 2M 2206-20 b 30 2M 2206-20 26.7 0.13 2M 2236+4751 b 12.5 2M 2236+4751 63.0 0.6 2M J2126-81 b 13.3 TYC 9486-927-1 24.8 0.4 2MASS J11193254 AB 3.7 2MASS J11193254 AB 2MASS J1450-7841 A 40 2MASS J1450-7841 A 75.0 0.04 2MASS J1450-7841 B 40 2MASS J1450-7841 B 75.0 0.04 2MASS J2250+2325 b 30 2MASS J2250+2325 41.5 30 Ari B b 9.88 30 Ari B 39.4 1.22 38 Vir b 4.51 38 Vir 1.18 4 Uma b 7.1 4 Uma 78.5 1.234 42 Dra b 3.88 42 Dra 97.3 0.98 47 Uma b 2.53 47 Uma 14.0 1.03 47 Uma c 0.54 47 Uma 14.0 1.03 47 Uma d 1.64 47 Uma 14.0 1.03 51 Eri b 9.1 51 Eri 29.4 1.75 51 Peg b 0.47 51 Peg 14.7 1.11 55 Cnc b 0.84 55 Cnc 12.3 0.905 55 Cnc c 0.1784 55 Cnc 12.3 0.905 55 Cnc d 3.86 55 Cnc 12.3 0.905 55 Cnc e 0.02547 55 Cnc 12.3 0.905 55 Cnc f 0.1479 55 -
Exoplanet Meteorology: Characterizing the Atmospheres Of
Exoplanet Meteorology: Characterizing the Atmospheres of Directly Imaged Sub-Stellar Objects by Abhijith Rajan A Dissertation Presented in Partial Fulfillment of the Requirements for the Degree Doctor of Philosophy Approved April 2017 by the Graduate Supervisory Committee: Jennifer Patience, Co-Chair Patrick Young, Co-Chair Paul Scowen Nathaniel Butler Evgenya Shkolnik ARIZONA STATE UNIVERSITY May 2017 ©2017 Abhijith Rajan All Rights Reserved ABSTRACT The field of exoplanet science has matured over the past two decades with over 3500 confirmed exoplanets. However, many fundamental questions regarding the composition, and formation mechanism remain unanswered. Atmospheres are a window into the properties of a planet, and spectroscopic studies can help resolve many of these questions. For the first part of my dissertation, I participated in two studies of the atmospheres of brown dwarfs to search for weather variations. To understand the evolution of weather on brown dwarfs we conducted a multi- epoch study monitoring four cool brown dwarfs to search for photometric variability. These cool brown dwarfs are predicted to have salt and sulfide clouds condensing in their upper atmosphere and we detected one high amplitude variable. Combining observations for all T5 and later brown dwarfs we note a possible correlation between variability and cloud opacity. For the second half of my thesis, I focused on characterizing the atmospheres of directly imaged exoplanets. In the first study Hubble Space Telescope data on HR8799, in wavelengths unobservable from the ground, provide constraints on the presence of clouds in the outer planets. Next, I present research done in collaboration with the Gemini Planet Imager Exoplanet Survey (GPIES) team including an exploration of the instrument contrast against environmental parameters, and an examination of the environment of the planet in the HD 106906 system. -
![Arxiv:1808.00476V1 [Astro-Ph.SR] 1 Aug 2018 Big Ae Stars but Not for Several Herbig Be Stars (Fairlamb Et Al](https://docslib.b-cdn.net/cover/2783/arxiv-1808-00476v1-astro-ph-sr-1-aug-2018-big-ae-stars-but-not-for-several-herbig-be-stars-fairlamb-et-al-672783.webp)
Arxiv:1808.00476V1 [Astro-Ph.SR] 1 Aug 2018 Big Ae Stars but Not for Several Herbig Be Stars (Fairlamb Et Al
Astronomy & Astrophysics manuscript no. Vioque_et_al_2018 c ESO 2018 August 3, 2018 Gaia DR2 study of Herbig Ae/Be stars M. Vioque1; 2?, R. D. Oudmaijer1, D. Baines3, I. Mendigutía4, and R. Pérez-Martínez2 1 School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, UK. 2 Ingeniería de Sistemas para la Defensa de España (Isdefe), XMM/Newton Science Operations Centre, ESA-ESAC Campus, PO Box 78, 28691 Villanueva de la Cañada, Madrid, Spain. 3 Quasar Science Resources for ESA-ESAC, ESAC Science Data Center, PO Box 78, 28691 Villanueva de la Cañada, Madrid, Spain. 4 Centro de Astrobiología (CSIC-INTA), Departamento de Astrofísica, ESA-ESAC Campus, PO Box 78, 28691 Villanueva de la Cañada, Madrid, Spain. Accepted for publication in Astronomy & Astrophysics. ABSTRACT Aims. We use Gaia Data Release 2 (DR2) to place 252 Herbig Ae/Be stars in the HR diagram and investigate their characteristics and properties. Methods. For all known Herbig Ae/Be stars with parallaxes in Gaia DR2, we collected their atmospheric parameters and photometric and extinction values from the literature. To these data we added near- and mid-infrared photometry, collected Hα emission line properties such as equivalent widths and line profiles, and their binarity status. In addition, we developed a photometric variability indicator from Gaia’s DR2 information. Results. We provide masses, ages, luminosities, distances, photometric variabilities and infrared excesses homogeneously derived for the most complete sample of Herbig Ae/Be stars to date. We find that high mass stars have a much smaller infrared excess and have much lower optical variabilities compared to lower mass stars, with the break at around 7M .Hα emission is generally correlated with infrared excess, with the correlation being stronger for infrared emission at wavelengths tracing the hot dust closest to the star. -
Chemistry in Circumstellar Disks: CS Toward HL Tauri
THE AsTROPHYSICAL JoURNAL, 391 : L99--L103, 1992 June 1 © 1992. The American Astronomical Society. All rights reserved. Printed in U.S.A. 1992ApJ...391L..99B CHEMISTRY IN CIRCUMSTELLAR DISKS: CS TOWARD HL TAURI GEOFFREY A. BLAKE,1 EWINE F. VAN DISHOECK,1 ' 2 AND ANNEILA I. SARGENT3 Received 1991 December 27; accepted 1992 March 19 ABSTRACT High-resolution millimeter-wave aperture synthesis images of the CS J = 2-+ 1 and dust continuum emission toward the young star HL Tauri have been combined with single-dish spectra of the higher J CS transitions in order to probe the chemical and physical structure of circumstellar material in this source. We find that the extended molecular cloud surrounding HL Tau is similar to other Taurus dark cloud cores, having 'Jk· r ~ 4 5 3 8 10-20 K, nH2 ~ 10 -10 cm- , and x(CS) = N(CS)/N(H 2) ~ (1-2) x 10- • In contrast, the gas-phase cs'~b~n dance in the circumstellar disk is depleted by factors of at least 25-50, and perhaps considerably more. These results are consistent with substantial depletion onto grains, or a transition from kinetically controlled chem istry in the molecular cloud to thermodynamically controlled chemistry in the outer regions of the circumstel lar disk. Dust continuum emission at 3.06 mm, although unresolved in a 3':0 beam, appears centered on the stellar position; combined with other millimeter-wave measurements its intensity indicates an emissivity index of P = 1.2 ± 0.3. This P may reflect grain growth via depletion and aggregation or compositional evolution, and suggests that the 3.06 mm dust opacity exceeds unity within 8-10 AU of HL Tauri. -
Astronomy Astrophysics
A&A 453, 101–119 (2006) Astronomy DOI: 10.1051/0004-6361:20053894 & c ESO 2006 Astrophysics On the difference between nuclear and contraction ages, W. Lyra1,2,3,A.Moitinho4,N.S.vanderBliek1,andJ.Alves5 1 Cerro Tololo Interamerican Observatory, Casilla 603 La Serena, Chile 2 Observatório do Valongo/UFRJ, Ladeira do Pedro Antônio 43, 20080-090 Rio de Janeiro, Brazil 3 Department of Astronomy and Space Physics, Uppsala Astronomical Observatory, Box 515, 751 20 Uppsala, Sweden e-mail: [email protected] 4 Observatório Astronómico de Lisboa, Tapada da Ajuda, 1349-018 Lisbon, Portugal 5 European Southern Observatory, Karl-Schwarzschild 2, 85748 Garching, Germany Received 23 July 2005 / Accepted 20 February 2006 ABSTRACT Context. Ages derived from low mass stars still contracting onto the main sequence often differ from ages derived from the high mass ones that have already evolved away from it. Aims. We investigate the general claim of disagreement between these two independent age determinations by presenting UBVRI pho- tometry for the young galactic open clusters NGC 2232, NGC 2516, NGC 2547 and NGC 4755, spanning the age range ∼10–150 Myr Methods. We derived reddenings, distances, and nuclear ages by fitting ZAMS and isochrones to color–magnitudes and color–color di- agrams. To derive contraction ages, we used four different pre-main sequence models, with an empirically calibrated color-temperature relation to match the Pleiades cluster sequence. Results. When exclusively using the V vs. V − I color–magnitude diagram and empirically calibrated isochrones, there is consistency between nuclear and contraction ages for the studied clusters. -
High-Resolution Optical and Near-Infrared Imaging of Young Circumstellar Disks
HIGH-RESOLUTION OPTICAL AND NEAR-INFRARED IMAGING OF YOUNG CIRCUMSTELLAR DISKS MARK McCAUGHREAN Astrophysikalisches Institut Potsdam KARL STAPELFELDT Jet Propulsion Laboratory, California Institute of Technology and LAIRD CLOSE Institute for Astronomy, University of Hawaii In the past five years, observations at optical and near-infrared wavelengths obtained with the Hubble Space Telescope and ground-based adaptive op- tics have provided the first well-resolved images of young circumstellar disks which may form planetary systems. We review these two observational tech- niques and highlight their results by presenting prototype examples of disks imaged in the Taurns-Auriga and Orion star-forming regions. As appropri- ate, we discuss the disk parameters that may be typically derived from the observations, as well as the implications that the observations may have on our understanding of, for example, the role of the ambient environment in shaping the disk evolution. We end with a brief summary of the prospects for future improvements in space- and ground-based optical/IR imaging tech- niques, and how they may impact disk studies. I. DIRECT IMAGING OF CIRCUMSTELLAR DISKS The Copernican demotion of humankind away from the center of our local planetary system also provided the shift in perspective re- quired to understand its cosmogony. Once it was apparent that the solar system comprised a number of planets in essentially circular and coplanar orbits around the Sun, theories for its formation were devel- oped involving condensation from a rotating disk-shaped primordial nebula, or Urnebel. The so-called "Kant-Laplace nebular hypothesis" eventually held sway in the latter half of the twentieth century af- ter lengthy competition with rival "catastrophic" theories (see Koerner 1997 for a review), and was subsequently vindicated by the discovery of analogues to the Urnebel around young stars elsewhere in the galaxy. -
WIS-2015-07-Radioastronomie ALMA Teil4.Pdf (Application/Pdf 4.0
Das Projekt ALMA Mater* Teil 4: Eine Beobachtung, die es in sich hat: eine „Kinderstube“ für Planeten *Wir verwenden die Bezeichnung Alma Mater als Synonym für eine Universität. Seinen Ursprung hat das Doppelwort im Lateinischen (alma: nähren, mater: Mutter). Im übertragenen Sinne ernährt die (mütterliche) Universität ihre Studenten mit Wissen. Und weiter gesponnen ernährt das Projekt ALMA auch die Schüler und Studenten mit Anreizen für das Lernen. (Zudem bedeutet das spanische Wort ‚Alma‘: Seele.) In Bezug (Materie bei T-Tauri-Sternen) zum Beitrag „Der Staubring von GG Tauri“ von Wolfgang Brandner in der Zeitschrift „Sterne und Weltraum“ (SuW) 7/2015, S.30/31, WIS-ID: 1285836 Olaf Fischer Im folgenden WIS-Beitrag steht ein atemberaubendes Beobachtungsergebnis von ALMA im Brennpunkt – die detaillierte Abbildung einer protoplanetaren Scheibe um einen entstehenden Stern – die potentielle Geburtsstätte für Planeten. Neben Beschreibungen und Erklärungen werden vor allem verschiedenartige Aktivitäten (Rechnungen zur Ma und Ph, Arbeit mit Karten, Bildauswertung, Diagramminterpretation, Papiermodell, Quartett) für Schüler angeboten, um diese Beobachtung und damit im Zusammenhang stehende Inhalte (insbesondere die Sternentstehung) besser zu verstehen, auch indem diese den Nutzen des Schulwissen entdecken. Der Wert von Kenntnissen auf verschiedenen Gebieten (Sprache, Mathematik, Naturwis- senschaft, Technik) wird spürbar. Der Beitrag eignet sich als Grundlage für Schülervorträge, die Arbeit in einer AG, wie auch für den Fachunterricht in der Oberstufe. -
Basic Notations
Appendix A Basic Notations In this Appendix, the basic notations for the mathematical operators and astronom- ical and physical quantities used throughout the book are given. Note that only the most frequently used quantities are mentioned; besides, overlapping symbol definitions and deviations from the basically adopted notations are possible, when appropriate. Mathematical Quantities and Operators kxk is the length (norm) of vector x x y is the scalar product of vectors x and y rr is the gradient operator in the direction of vector r f f ; gg is the Poisson bracket of functions f and g K.m/ or K.k/ (where m D k2) is the complete elliptic integral of the first kind with modulus k E.m/ or E.k/ is the complete elliptic integral of the second kind F.˛; m/ is the incomplete elliptic integral of the first kind E.˛; m/ is the incomplete elliptic integral of the second kind ƒ0 is Heuman’s Lambda function Pi is the Legendre polynomial of degree i x0 is the initial value of a variable x Coordinates and Frames x, y, z are the Cartesian (orthogonal) coordinates r, , ˛ are the spherical coordinates (radial distance, longitude, and latitude) © Springer International Publishing Switzerland 2017 171 I. I. Shevchenko, The Lidov-Kozai Effect – Applications in Exoplanet Research and Dynamical Astronomy, Astrophysics and Space Science Library 441, DOI 10.1007/978-3-319-43522-0 172 A Basic Notations In the three-body problem: r1 is the position vector of body 1 relative to body 0 r2 is the position vector of body 2 relative to the center of mass of the inner -
Planet Formation Phil Armitage
Planet Formation Phil Armitage Colorado è Stony Brook / Simons CCA overview • stone age planet formation – formation of planetary systems from a smooth radial distribution of km-scale planetesimals embedded in gas, with no migration • planetesimal • planetesimals formation or pebbles? • migration • gas accretion How do we form observed systems? Is there a timing problem? classical planet formation Adopt effective initial conditions: radially smooth distribution of small (100m – km) planetesimals embedded in gas, which acts to damp {e,i} but does not cause migration • growth phases: runaway, oligarchic final assembly / giant impacts • if fast enough final outcome is ~determined by stability M 1/3 r = p a Hill 3M ✓ ⇤ ◆ 1/4 tinstability = f(∆a/Mp ) • collisions make a small-N system more stable classical planet formation t / Myr 100 Ratio of collisions to scatterings is 10 f(vK / vesc), favors collisions for MSun at a ~ AU and less 1 “in situ” formation e 1 AU 2 AU 3 AU • disk with a few ME / AU at 1 AU will work • requirement of stability can hide a multitude of sins • many important but lesser constraints (small mass of Mars…) classical planet formation quasi-static envelope extends to rHill, rBondi core grows from accretion of planetesimals cooling is limited by grain opacity in radiative zone in the envelope “success” requires reaching Menv ~ Mcore ~ 5-20 ME within gas disk lifetime possible at few AU if the gravitational focusing factor 2 [1 + (vesc / σ) ] is large (small planetesimals) and κ low what’s wrong with this story? • major