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Phase Closure Nulling of HD 59717 with AMBER/VLTI. Detection of the Close Faint Companion
Astronomy & Astrophysics manuscript no. 11037 c ESO 2018 May 19, 2018 Phase closure nulling of HD 59717 with AMBER/VLTI⋆ Detection of the close faint companion G. Duvert, A. Chelli, F. Malbet and P. Kern Laboratoire d’Astrophysique de Grenoble and Mariotti Center, UMR 5571 Universit´eJoseph Fourier/CNRS, B.P. 53, 38041 Grenoble Cedex 9, France e-mail: [email protected] date received; date accepted ABSTRACT Aims. The detection of close and faint companions is an essential step in many astrophysical fields, including the search for planetary companions. A new method called “phase closure nulling” has been proposed for the detection of such faint and close companions based on interferometric observations when the system visibility amplitude is close to zero due to the large diameter of the primary star. We aim at demonstrating this method by analyzing observations obtained on the spectroscopic binary HD 59717. Methods. Using the AMBER/VLTI instrument in the K-band with 1500 spectral resolution, we record the spectrally dispersed closures phases of the SB1 binary HD 59717 with a three-baseline combination∼ adequate for applying phase closure methods. After a careful data reduction, we fit the primary diameter, the binary flux ratio, and the separation using the phase closure data. Results. We detect the 5-mag fainter companion of HD 59717 at a distance of 4 stellar radii from the primary. We determine the diameter of the primary, infer the secondary’s spectral type and determine the masses and sizes of the stars in the binary system. This is one of the highest contrasts detected by interferometry between a companion and its parent star. -
Radial Velocity Variations in Red Giant Stars: Pulsations, Spots and Planets
RADIAL VELOCITY VARIATIONS IN RED GIANT STARS: PULSATIONS, SPOTS AND PLANETS RADIAL VELOCITY VARIATIONS IN RED GIANT STARS: PULSATIONS, SPOTS AND PLANETS Proefschrift ter verkrijging van de graad van Doctor aan de Universiteit Leiden, op gezag van de Rector Magnificus prof. mr. P. F. van der Heijden, volgens besluit van het College voor Promoties te verdedigen op 18 september 2007 klokke 13:45 uur door Saskia Hekker geboren te Heeze in 1978 Promotiecommissie Promotor: Prof. dr. A. Quirrenbach Sterrewacht Leiden Landessternwarte Heidelberg Promotor: Prof. dr. C. Aerts Katholieke Universiteit Leuven Radboud Universiteit Nijmegen Co-promotor: Dr. I. A. G. Snellen Sterrewacht Leiden Overige leden: Prof. dr. E. F. van Dishoeck Sterrewacht Leiden Prof. dr. K. H. Kuijken Sterrewacht Leiden Prof. dr. P. T. de Zeeuw Sterrewacht Leiden Dr. M. Hogerheijde Sterrewacht Leiden Dr. J. Lub Sterrewacht Leiden Dit proefschrift is tot stand gekomen met steun van No pain, no gain Contents 1 Introduction 1 1.1 Redgiantstars................................... 2 1.2 Observations ................................... 4 1.2.1 Iodinecell................................. 4 1.2.2 SimultaneousThAr............................ 4 1.3 Oscillations .................................... 5 1.3.1 Excitationmechanism .......................... 9 1.3.2 Asymptoticrelation. 10 1.3.3 Scalingrelations ............................. 10 1.4 Starspots...................................... 11 1.5 Sub-stellarcompanions . ... 12 1.6 Why can oscillations, spots and companions be observed as -
The Long-Period Galactic Cepheid RS Puppis - I
The long-period Galactic Cepheid RS Puppis - I. A geometric distance from its light echoes Pierre Kervella, Antoine Mérand, Laszlo Szabados, Pascal Fouqué, David Bersier, Emanuela Pompei, Guy Perrin To cite this version: Pierre Kervella, Antoine Mérand, Laszlo Szabados, Pascal Fouqué, David Bersier, et al.. The long- period Galactic Cepheid RS Puppis - I. A geometric distance from its light echoes. Astronomy and Astrophysics - A&A, EDP Sciences, 2007, 480 ( 1), pp.167 - 178. 10.1051/0004-6361:20078961. hal-00250342 HAL Id: hal-00250342 https://hal.archives-ouvertes.fr/hal-00250342 Submitted on 11 Feb 2008 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Astronomy & Astrophysics manuscript no. ms8961.hyper15682 c ESO 2008 February 11, 2008 The long-period Galactic Cepheid RS Puppis I. A geometric distance from its light echoes⋆ P. Kervella1, A. M´erand2, L. Szabados3, P. Fouqu´e4, D. Bersier5, E. Pompei6, and G. Perrin1 1 LESIA, Observatoire de Paris, CNRS UMR 8109, UPMC, Universit´eParis Diderot, 5 Place Jules Janssen, F-92195 Meudon, France 2 Center for High Angular Resolution Astronomy, Georgia State University, PO Box 3965, Atlanta, Georgia 30302-3965, USA 3 Konkoly Observatory, H-1525 Budapest XII, P. -
Target Selection for the SUNS and DEBRIS Surveys for Debris Discs in the Solar Neighbourhood
Mon. Not. R. Astron. Soc. 000, 1–?? (2009) Printed 18 November 2009 (MN LATEX style file v2.2) Target selection for the SUNS and DEBRIS surveys for debris discs in the solar neighbourhood N. M. Phillips1, J. S. Greaves2, W. R. F. Dent3, B. C. Matthews4 W. S. Holland3, M. C. Wyatt5, B. Sibthorpe3 1Institute for Astronomy (IfA), Royal Observatory Edinburgh, Blackford Hill, Edinburgh, EH9 3HJ 2School of Physics and Astronomy, University of St. Andrews, North Haugh, St. Andrews, Fife, KY16 9SS 3UK Astronomy Technology Centre (UKATC), Royal Observatory Edinburgh, Blackford Hill, Edinburgh, EH9 3HJ 4Herzberg Institute of Astrophysics (HIA), National Research Council of Canada, Victoria, BC, Canada 5Institute of Astronomy (IoA), University of Cambridge, Madingley Road, Cambridge, CB3 0HA Accepted 2009 September 2. Received 2009 July 27; in original form 2009 March 31 ABSTRACT Debris discs – analogous to the Asteroid and Kuiper-Edgeworth belts in the Solar system – have so far mostly been identified and studied in thermal emission shortward of 100 µm. The Herschel space observatory and the SCUBA-2 camera on the James Clerk Maxwell Telescope will allow efficient photometric surveying at 70 to 850 µm, which allow for the detection of cooler discs not yet discovered, and the measurement of disc masses and temperatures when combined with shorter wavelength photometry. The SCUBA-2 Unbiased Nearby Stars (SUNS) survey and the DEBRIS Herschel Open Time Key Project are complimentary legacy surveys observing samples of ∼500 nearby stellar systems. To maximise the legacy value of these surveys, great care has gone into the target selection process. This paper describes the target selection process and presents the target lists of these two surveys. -
Precise Radial Velocities of Giant Stars. III. Spectroscopic Stellar Parameters
Astronomy & Astrophysics manuscript no. finalversionlcor6nov1 c ESO 2018 October 28, 2018 Precise radial velocities of giant stars. III.⋆ Spectroscopic stellar parameters S. Hekker1 and J. Mel´endez2 1 Leiden Observatory, Leiden University, P.O. Box 9513, 2300 RA Leiden, The Netherlands 2 Research School of Astronomy & Astrophysics, Mount Stromlo Observatory, Cotter Road, Weston Creek, ACT 2611, Australia Received ¡date¿; accepted ¡date¿ ABSTRACT Context. A radial velocity survey of about 380 G and K giant stars is ongoing at Lick observatory. For each star we have a high signal to noise ratio template spectrum, which we use to determine spectroscopic stellar parameters. Aims. The aim of this paper is to present spectroscopic stellar parameters, i.e. effective temperature, surface gravity, metallicity and rotational velocity for our sample of G and K giant stars. Methods. Effective temperatures, surface gravities and metallicities are determined from the equivalent width of iron lines, by imposing exci- tation and ionisation equilibrium through stellar atmosphere models. Rotational velocities are determined from the full width at half maximum (FWHM) of moderate spectral lines. A calibration between the FWHM and total broadening (rotational velocity and macro turbulence) is ob- tained from stars in common between our sample and the sample from Gray (1989). Macro turbulence is determined from the macro turbulence vs. spectral type relations from Gray (2005). Results. The metallicity we derive is essentially equal to the literature values, while the effective temperature and surface gravity are slightly higher by 56 K and 0.15 dex, respectively. A method comparison is performed with 72 giants in common with Luck and Heiter (2007), which shows that both methods give similar results. -
Exploring Milky Way Halo Substructures with Large-Area Sky Surveys
EXPLORING MILKY WAY HALO SUBSTRUCTURES WITH LARGE-AREA SKY SURVEYS A Dissertation by TING LI Submitted to the Office of Graduate and Professional Studies of Texas A&M University in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY Chair of Committee, Darren L. DePoy Co-Chair of Committee, Jennifer L. Marshall Committee Members, Nicholas B. Suntzeff Casey J. Papovich Sherry J. Yennello Head of Department, George R. Welch August 2016 Major Subject: Physics Copyright 2016 Ting Li ABSTRACT Over the last two decades, our understanding of the Milky Way has been improved thanks to large data sets arising from large-area digital sky surveys. The stellar halo is now known to be inhabited by a variety of spatial and kinematic stellar substructures, including stellar streams and stellar clouds, all of which are predicted by hierarchical Lambda Cold Dark Matter models of galaxy formation. In this dissertation, we first present the analysis of spectroscopic observations of individual stars from the two candidate structures discovered using an M-giant catalog from the Two Micron All-Sky Survey. The follow-up observations show that one of the candidates is a genuine structure which might be associated with the Galactic Anticenter Stellar Structure, while the other one is a false detection due to the systematic photometric errors in the survey or dust extinction in low Galactic latitudes. We then presented the discovery of an excess of main sequence turn-off stars in the direction of the constellations of Eridanus and Phoenix from the first-year data of the Dark Energy Survey (DES) { a five-year, 5,000 deg2 optical imaging survey in the Southern Hemisphere. -
STTR) Program Proposals Selected for Negotiation of STTR Phase I Contracts Sorted by Company and Proposal Number
National Aeronautics and Space Administration Small Business Technology Transfer (STTR) Program Proposals Selected for Negotiation of STTR Phase I Contracts Sorted by Company and Proposal Number AEROMOVER SYSTEMS COW 2500 BISHOP CIRCLE DEXTER, MI 48130 RONALD A. MEYER 313-426-2376 THE UNIIVERSITY OF MICHIGAN 3003 SOUTH STATE ST A” ARBOR, MI 48109 94-03-940085 LaRC DIFFERENTIATED UNIVERSAL END EFFECTOR AIRBORNE RESEARCH ASSOCIATES 46 KENDAL COMMON RD WESTON, MA 02193 RALPH J. MARKSON 617-899-1834 MASSACHUSETTS INSTITUTE OF TECHNOLOGY 244 WOOD ST LEXINGTON, MA 02173 94-0 1-940092 LaRC LASI: LIGHTNING AND STORM INTENSITY/WEATHER WARNING SYSTEM AMHERST SYSTEMS INC 30 WILSON RD BUFFALO, NY 14221 DONALD A. HESS 716-631-0610 STATE UNWERSlTY OF NEW YORK AT BUFFALO 3435 MAIN ST BUFFALO, NY 14214 94-03-940 104 LaRC FOVEAL SENSOR AND IMAGE PROCESSOR PROTOTYPE ARNAV SYSTEMS INC 16923 MERIDIAN EAST PUYALLUP, WA 98373 FRANK WILLIAMS 206-848-6060 RESEARCH TRIANGLE INSTITUTE 525 BUTLER FARM RD SUITE 108 HAMPTON, VA 23666-1564 94-0 1-940024 LaRC AN AFFORDABLE GENERAL AVIATION INTEGRATED COCKPIT DISPLAY SYSTEM -more- -2- CIRRUS DESIGN COW 4515 TAYLOR CIRCLE DULUTH, MN 55811 DEAN VOGEL 218-727-2737 RESEARCH TRIANGLE INSTITUTE 3040 CORNWALLIS RD RESEARCH TRIANGLE PARK, NC 27709 94-0 1-940152 LaRC LOW COST AIRCRAFT ENGINE AND FLIGHT DATA RECORDING SYSTEM CYBER.NET SYSTEMS COW 1919 GREEN RD, SUITE B-101 ANN ARBOR, MI 48105 HEIDI N. JACOBUS 3 13-668-2567 THE UNIVERSITY OF MICHIGAN COLLEGE OF ENGINEERING OFFICE OF TECHNOLOGY TRANSFER 2901 HUBBARD ANN ARBOR, MI 48109-2106 94-0 1-940060 LaRC A LOW-COST HIGH-PERFORMANCE VISUAL-AUDITORY-TACTILE VIRTUAL REALITY TRAINER ENDOROBOTICS COW 5 DEERWOOD TRAIL P.O. -
Observed Stellar Spectra As Templates for Gaia
Universit`adegli Studi di Padova DIPARTIMENTO DI ASTRONOMIA Dottorato di Ricerca in Astronomia XXIII ciclo Observed Stellar Spectra As Templates For Gaia Coordinatore: Prof. Giampaolo Piotto Supervisori: Prof. Antonella Vallenari Prof. Ulisse Munari Dottoranda: Tenay Saguner 2 31 Gennaio 2011 To My Family & To Prof. I. Ethem Derman Contents Index i Figures List x Tables List x 1 Introduction 1 2 The Gaia Mission 3 2.1 OverviewOfTheGaiaMission . 5 2.1.1 MeasurementPrinciples . 5 2.1.2 ObservationPrinciple . 7 2.1.3 Instruments And Performances . 7 2.1.4 TheAccuracyOfGaiaMeasurements . 10 2.2 The Classification of Gaia objects . ..... 15 2.3 TheFinalCatalogue ............................... 16 2.4 TheImportanceoftrainingdata . 16 3 The Red Clump Stars 19 3.1 The Structure And The Evolution Of the Red Clump . 19 3.2 RedClumpStarsInTheLiterature. 21 4 Target Selection and The Input Catalog 23 4.1 TargetSelectionCriteria. 23 i ii 5 Observations And Data Reduction 27 5.1 The B&C Spectrograph At The 1.22 meter TelescopeInAsiago ............................... 27 5.2 Softwares To Use The 1.22 meter Telescope . ..... 29 5.3 DataAcquisitionAtTheTelescope . 29 5.4 Selecting The Wavelength Interval To Observe . ....... 31 5.5 DataReduction.................................. 35 5.5.1 WavelengthCalibration . 38 5.5.2 ContinuumNormalization . 38 5.5.3 HeliocentricCorrection . 41 6 Measuring Radial Velocities 45 6.1 Cross-CorrelationTechnique. 45 6.2 Accuracy Tests With IAU Radial Velocity Standards . ........ 48 6.3 ExtendedTestsOnRadialVelocities . ..... 52 7 Atmospheric Parameter Determonation 55 7.1 χ2 Technique ................................... 55 7.1.1 TheSyntheticspectralLibrary . 56 7.1.2 The χ2 Methods ............................. 58 7.2 Accuracy Tests With Red Clump Stars In the Literature . -
The Long-Period Galactic Cepheid RS Puppis-I. a Geometric Distance from Its Light Echoes
Astronomy & Astrophysics manuscript no. ms8961 c ESO 2018 October 24, 2018 The long-period Galactic Cepheid RS Puppis I. A geometric distance from its light echoes⋆ P. Kervella1, A. M´erand2, L. Szabados3, P. Fouqu´e4, D. Bersier5, E. Pompei6, and G. Perrin1 1 LESIA, Observatoire de Paris, CNRS UMR 8109, UPMC, Universit´eParis Diderot, 5 Place Jules Janssen, F-92195 Meudon, France 2 Center for High Angular Resolution Astronomy, Georgia State University, PO Box 3965, Atlanta, Georgia 30302-3965, USA 3 Konkoly Observatory, H-1525 Budapest XII, P. O. Box 67, Hungary 4 Observatoire Midi-Pyr´en´ees, Laboratoire d’Astrophysique, CNRS UMR 5572, Universit´ePaul Sabatier - Toulouse 3, 14 avenue Edouard Belin, F-31400 Toulouse, France 5 Astrophysics Research Institute, Liverpool John Moores University, Twelve Quays House, Egerton Wharf, Birkenhead, CH411LD, United Kingdom 6 European Southern Observatory, Alonso de Cordova 3107, Casilla 19001, Vitacura, Santiago 19, Chile Received ; Accepted ABSTRACT Context. The bright southern Cepheid RS Pup is surrounded by a circumstellar nebula reflecting the light from the central star. The propagation of the light variations from the Cepheid inside the dusty nebula creates spectacular light echoes that can be observed up to large distances from the star itself. This phenomenon is currently unique in this class of stars. Aims. For this relatively distant star, the trigonometric parallax available from Hipparcos has a low accuracy. A careful observation of the light echoes has the potential to provide a very accurate, geometric distance to RS Pup. Methods. We obtained a series of CCD images of RS Pup with the NTT/EMMI instrument covering the variation period of the star (P = 41.4 d), allowing us to track the progression of the light wavefronts over the nebular features surrounding the star. -
The Circumstellar Envelopes of the Cepheids L Car and RS
The circumstellar envelopes of the Cepheids L Car and RS Pup - Comparative study in the infrared with Spitzer, VLT/VISIR and VLTI/MIDI Pierre Kervella, Antoine M´erand,Alexandre Gallenne To cite this version: Pierre Kervella, Antoine M´erand,Alexandre Gallenne. The circumstellar envelopes of the Cepheids L Car and RS Pup - Comparative study in the infrared with Spitzer, VLT/VISIR and VLTI/MIDI. Astronomy and Astrophysics - A&A, EDP Sciences, 2009, In press. <hal- 00358742> HAL Id: hal-00358742 https://hal.archives-ouvertes.fr/hal-00358742 Submitted on 4 Feb 2009 HAL is a multi-disciplinary open access L'archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destin´eeau d´ep^otet `ala diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publi´esou non, lished or not. The documents may come from ´emanant des ´etablissements d'enseignement et de teaching and research institutions in France or recherche fran¸caisou ´etrangers,des laboratoires abroad, or from public or private research centers. publics ou priv´es. Astronomy & Astrophysics manuscript no. ms1307astroph.hyper16481 c ESO 2009 February 10, 2009 The circumstellar envelopes of the Cepheids ℓ Car and RS Pup⋆ Comparative study in the infrared with Spitzer, VLT/VISIR and VLTI/MIDI P. Kervella1, A. M´erand2, and A. Gallenne2,1 1 LESIA, Observatoire de Paris, CNRS, UPMC, Universit´eParis Diderot, 5 Place Jules Janssen, F-92195 Meudon Cedex, France 2 European Southern Observatory, Alonso de C´ordova 3107, Casilla 19001, Santiago 19, Chile Received ; Accepted ABSTRACT Context. Compact circumstellar envelopes (CSEs) have now been detected around several Cepheids by interferometry. -
Phase Closure Nulling of HD 59717 with AMBER/VLTI . Detection of the Close Faint Companion G
View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by HAL-INSU Phase closure nulling of HD 59717 with AMBER/VLTI . Detection of the close faint companion G. Duvert, A. Chelli, F. Malbet, P. Kern To cite this version: G. Duvert, A. Chelli, F. Malbet, P. Kern. Phase closure nulling of HD 59717 with AM- BER/VLTI . Detection of the close faint companion. Astronomy and Astrophysics - A&A, EDP Sciences, 2010, 509, pp.66. <10.1051/0004-6361/200811037>. <insu-00450990> HAL Id: insu-00450990 https://hal-insu.archives-ouvertes.fr/insu-00450990 Submitted on 27 Jan 2010 HAL is a multi-disciplinary open access L'archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destin´eeau d´ep^otet `ala diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publi´esou non, lished or not. The documents may come from ´emanant des ´etablissements d'enseignement et de teaching and research institutions in France or recherche fran¸caisou ´etrangers,des laboratoires abroad, or from public or private research centers. publics ou priv´es. Astronomy & Astrophysics manuscript no. 11037.hyper5122 c ESO 2010 January 27, 2010 Phase closure nulling of HD 59717 with AMBER/VLTI⋆ Detection of the close faint companion G. Duvert, A. Chelli, F. Malbet and P. Kern Laboratoire d’Astrophysique de Grenoble and Mariotti Center, UMR 5571 Universit´eJoseph Fourier/CNRS, B.P. 53, 38041 Grenoble Cedex 9, France e-mail: [email protected] date received; date accepted ABSTRACT Aims. -
New Debris Disks Around Nearby Main-Sequence Stars: Impact on the Direct Detection of Planets C
The Astrophysical Journal, 652:1674Y1693, 2006 December 1 # 2006. The American Astronomical Society. All rights reserved. Printed in U.S.A. NEW DEBRIS DISKS AROUND NEARBY MAIN-SEQUENCE STARS: IMPACT ON THE DIRECT DETECTION OF PLANETS C. A. Beichman,1 G. Bryden,2 K. R. Stapelfeldt,2 T. N. Gautier,2 K. Grogan,2 M. Shao,2 T. Velusamy,2 S. M. Lawler,1 M. Blaylock,3 G. H. Rieke,3 J. I. Lunine,3 D. A. Fischer,4 G. W. Marcy,5 J. S. Greaves,6 M. C. Wyatt,7 W. S. Holland,8 and W. R. F. Dent8 Received 2006 April 17; accepted 2006 July 28 ABSTRACT Using the MIPS instrument on Spitzer, we have searched for infrared excesses around a sample of 82 stars, mostly F, G, and K main-sequence field stars, along with a small number of nearby M stars. These stars were selected for their suitability for future observations by a variety of planet-finding techniques. These observations provide information on the asteroidal and cometary material orbiting these stars, data that can be correlated with any planets that may even- tually be found. We have found significant excess 70 m emission toward 12 stars. Combined with an earlier study, we find an overall 70 m excess detection rate of 13% Æ 3% for mature cool stars. Unlike the trend for planets to be found preferentially toward stars with high metallicity, the incidence of debris disks is uncorrelated with metallicity. By newly identifying four of these stars as having weak 24 mexcesses(fluxes10% above the stellar photosphere), we confirm a trend found in earlier studies wherein a weak 24 m excess is associated with a strong 70 m excess.