DOCSLIB.ORG

Dharma Planet Survey of Fgkm Dwarfs: Survey Preparation and Early Science Results

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Dharma Planet Survey of Fgkm Dwarfs: Survey Preparation and Early Science Results DHARMA PLANET SURVEY OF FGKM DWARFS: SURVEY PREPARATION AND EARLY SCIENCE RESULTS By SIRINRAT SITHAJAN A DISSERTATION PRESENTED TO THE GRADUATE SCHOOL OF THE UNIVERSITY OF FLORIDA IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY UNIVERSITY OF FLORIDA 2018 ⃝c 2018 Sirinrat Sithajan I dedicate this to my family and friends who always love and support me unconditionally. ACKNOWLEDGMENTS I greatly appreciate many people for helping me achieve this success. Firstly, I would like to thank my parents for encouraging me to follow the career path I love, being an astronomer. This has brought my life full of great experiences and happiness. I especially want to thank my husband, San, who loves me unconditionally and always stands by my side. He usually gives me good advice and cheers me up when I have a hard time. I also would like to thank my advisor, Dr. Jian Ge, who has given me many great work opportunities including working at Kitt Peak Observatory. Staying overnight at the observatory, monitoring target stars, and taking data were a marvelous experience and made me more appreciate my research work. I would like to thank my dissertation committee: Dr. Jian Ge, Dr. Jonathan Tan, Dr. Katia Matcheva, and Dr. James Fry for their constructive advice. I want to thank my close friends from high school for always keeping in touch with me wherever they are in the world. We have been sharing stories about our life living abroad and how to deal with various difficulties. We sometimes meet up and travel together, so I never feel lonely. I would like to thank Dr. Bo Ma who gave me valuable advice when I got stuck on some particular points of my research, and he also helped me find bugs in my programs. I want to thank Nolan Grieves for proofreading my papers and giving constructive comments. Finally, I would like to thank UF classmates who have worked and had fun together. They made me had a wonderful graduate student life in the US. 4 TABLE OF CONTENTS page ACKNOWLEDGMENTS ................................... 4 LIST OF TABLES ...................................... 7 LIST OF FIGURES ..................................... 8 ABSTRACT ......................................... 11 CHAPTER 1 INTRODUCTION ................................... 13 1.1 Dharma Planet Survey .............................. 13 1.2 History of Radial Velocity Method to Detect Planets .............. 14 1.3 Motivations for Improving Planet Detection Sensitivity of Radial Velocity Surveys 15 1.4 Challenges in the Detection of Low Mass Planets ................ 17 1.4.1 Observing Cadence ............................ 17 1.4.2 Measurement Precision .......................... 18 1.5 Areas of Emphasize ............................... 20 2 TARGET SELECTION ................................. 21 2.1 Method ...................................... 21 2.2 Results ...................................... 23 2.3 Conclusions .................................... 25 3 SIMULATIONS OF OBSERVATIONS ......................... 37 3.1 Simulation Method ................................ 37 3.2 Results ...................................... 42 3.3 Conclusions .................................... 48 4 SIMULATIONS OF PLANET DETECTIONS ..................... 53 4.1 Simulation Method ................................ 53 4.1.1 Precision of Radial Velocity Measurements ............... 53 4.1.2 Simulated Radial Velocity Data ..................... 55 4.1.3 Planet Detectability ........................... 58 4.2 Results ...................................... 60 4.2.1 Planet Detectability of the Dharma Planet Survey ........... 60 4.2.2 Planet Yields ............................... 60 4.3 Conclusion .................................... 61 5 EFFECT OF TELLURIC LINES ON RADIAL VELOCITY MEASUREMENTS .... 65 5.1 Simulation Method ................................ 66 5 5.1.1 Simulated Observed Spectra ....................... 66 5.1.2 Precision of Radial Velocity Measurements ............... 70 5.1.3 Telluric Line Correction .......................... 72 5.1.3.1 The masking method ..................... 72 5.1.3.2 The modeling method ..................... 72 5.2 Results ...................................... 75 5.2.1 The Effect of Telluric Lines in Optical, Broad-Optical, and NIR Regions 75 5.2.2 Treatment of Telluric Contamination .................. 76 5.2.2.1 Optical wavelength region ................... 76 5.2.2.2 Broad-Optical and NIR wavelength regions .......... 77 5.3 Conclusions .................................... 79 6 CURRENT STATUS OF THE DHARMA PLANET SURVEY AND EARLY SCIENCE RESULTS ....................................... 88 6.1 Instrument and Pipeline Performance ...................... 88 6.2 Observation ................................... 90 6.3 Planet Detection ................................. 96 REFERENCES ........................................ 115 BIOGRAPHICAL SKETCH ................................. 120 6 LIST OF TABLES Table page 2-1 Reference sources of stellar properties used in the target selection. .......... 24 2-2 List of target stars for the Dharma Planet Survey and their stellar parameter values. 32 2-3 Minimum and maximum values for stellar parameters of the DPS targets in each spectral type. ..................................... 36 3-1 Percentage of available time that can be used for observation. ............ 41 3-2 Summary of observations for the target stars. ..................... 49 4-1 Planet yields of 150 target stars observed in the Dharma Planet Survey ....... 62 5-1 Signal to noise ratio of the simulated spectra with different effective temperatures (or spectral types) at 1.25 µm and 0.55 µm. ..................... 70 5-2 The fraction of stellar spectrum remaining for the RV precision calculation after contaminating telluric lines with different strengths are masked. ........... 74 6-1 The DPS target stars observed between October 2016 - April 2018. ......... 93 6-2 List of the planet and planet candidates from the Dharma Planet Survey. ...... 97 7 LIST OF FIGURES Figure page 1-1 Detection probability of planets with different masses and orbital periods around the stars observed in the Lick-Carnegie Exoplanet Survey ............... 18 1-2 Detection probability of planets with different masses and orbital periods around the stars observed in the Eta-Earth Survey ...................... 19 2-1 Distribution of the Right Ascensions and Declinations of the DPS target stars ... 25 2-2 Distance distribution of the DPS Targets ....................... 26 2-3 V magnitude distribution of the DPS Targets ..................... 27 2-4 H-R diagram of the DPS targets ........................... 28 2-5 Stellar mass distribution of the DPS Targets ..................... 29 2-6 Stellar rotational velocity distribution of the DPS Targets .............. 30 0 2-7 Log RHK index distribution of the DPS Targets .................... 31 3-1 Simulated observing schedule for December 29th, 2018 ................ 39 3-2 Kitt Peak weather statistics during 1999-2006 .................... 40 3-3 Comparison between simulated weather patterns of January 2017 and January 2018 42 3-4 Simulated weather in the night of December 29th, 2018 ............... 43 3-5 Simulated observing report for December 29th, 2018 ................. 44 3-6 The number of observations received by the target stars at the end of observing period ......................................... 45 3-7 Time span the target stars needed to obtained 100 observations ........... 45 3-8 Time span the target stars needed to obtained 100 observations as a function of RA 46 3-9 Simulated Observations of GJ 761.1 .......................... 46 3-10 Simulated Observations of GJ 708.4 .......................... 47 3-11 Simulated Observations of GJ 892 ........................... 48 4-1 The overall detection efficiency of the TOU spectrograph as a function of wavelength 55 4-2 Estimated RV measurement precisions of the DPS target stars ............ 56 4-3 Simulated RV data set 1 ................................ 58 8 4-4 Simulated RV data set 2 ................................ 59 4-5 Distribution of planet eccentricities used in simulating RV data ........... 60 4-6 Simulated RV data set 3 ................................ 61 4-7 Planet detectability of 0.5-MJ star .......................... 62 4-8 Planet detectability of the Dharma Planet Survey in the baseline case ........ 63 4-9 Planet detectability of the Dharma Planet Survey in the pessimistic case ...... 64 5-1 Synthetic atmospheric transmission used in simulating observed stellar spectra ... 68 5-2 Simulated stellar spectra with and without telluric lines ............... 69 5-3 Radial velocities measured from simulated observed spectra with different input barycentric velocities ........................................ 71 5-4 Spectral regions that are masked out from RV precision calculation due to strong telluric lines ...................................... 73 5-5 Simulated observed spectra after telluric lines are modeled and subtracted out ... 76 5-6 Radial velocity measurement error caused by telluric lines in the Optical, Broad-Optical, and NIR regions. .................................... 77 5-7 Radial velocity precision of the Optical, Broad-Optical, and NIR spectra contaminated with telluric lines, assuming SNR=200 ........................ 78 5-8 Radial velocity precision of the Optical, Broad-Optical, and NIR spectra contaminated with telluric lines, assuming SNR=1000 ........................ 79 5-9 Radial velocity precision of the Optical region when strong telluric lines are masked out,
Load more

Recommended publications
  • Lurking in the Shadows: Wide-Separation Gas Giants As Tracers of Planet Formation
    Lurking in the Shadows: Wide-Separation Gas Giants as Tracers of Planet Formation Thesis by Marta Levesque Bryan In Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy CALIFORNIA INSTITUTE OF TECHNOLOGY Pasadena, California 2018 Defended May 1, 2018 ii © 2018 Marta Levesque Bryan ORCID: [0000-0002-6076-5967] All rights reserved iii ACKNOWLEDGEMENTS First and foremost I would like to thank Heather Knutson, who I had the great privilege of working with as my thesis advisor. Her encouragement, guidance, and perspective helped me navigate many a challenging problem, and my conversations with her were a consistent source of positivity and learning throughout my time at Caltech. I leave graduate school a better scientist and person for having her as a role model. Heather fostered a wonderfully positive and supportive environment for her students, giving us the space to explore and grow - I could not have asked for a better advisor or research experience. I would also like to thank Konstantin Batygin for enthusiastic and illuminating discussions that always left me more excited to explore the result at hand. Thank you as well to Dimitri Mawet for providing both expertise and contagious optimism for some of my latest direct imaging endeavors. Thank you to the rest of my thesis committee, namely Geoff Blake, Evan Kirby, and Chuck Steidel for their support, helpful conversations, and insightful questions. I am grateful to have had the opportunity to collaborate with Brendan Bowler. His talk at Caltech my second year of graduate school introduced me to an unexpected population of massive wide-separation planetary-mass companions, and lead to a long-running collaboration from which several of my thesis projects were born.
    [Show full text]
  • Speckle Observations and Orbits of Multiple Stars 3
    Draft version September 2, 2019 A Preprint typeset using LTEX style emulateapj v. 12/16/11 , SPECKLE OBSERVATIONS AND ORBITS OF MULTIPLE STARS Andrei Tokovinin Cerro Tololo Inter-American Observatory, Casilla 603, La Serena, Chile Mark E. Everett National Optical Astronomy Observatory, 950 North Cherry Avenue, Tucson, AZ 85719, USA Elliott P. Horch∗ Department of Physics, Southern Connecticut State University, 501 Crescent Street, New Haven, CT 06515, USA Guillermo Torres Center for Astrophysics — Harvard & Smithsonian, 60 Garden Street, Cambridge, MA 02138, USA David W. Latham Center for Astrophysics — Harvard & Smithsonian, 60 Garden Street, Cambridge, MA 02138, USA Draft version September 2, 2019 ABSTRACT We report results of speckle-interferometric monitoring of visual hierarchical systems using the newly commissioned instrument NESSI at the 3.5-m WIYN telescope. During one year, 390 measurements of 129 resolved subsystems were made, while some targets were unresolved. Using our astrometry and archival data, we computed 36 orbits (27 for the first time). Spectro-interferometric orbits of seven pairs are determined by combining positional measurements with radial velocities measured, mostly, with the Center for Astrophysics digital speedometers. For the hierarchical systems HIP 65026 (periods 49 and 1.23 years) and HIP 85209 (periods 34 and 1.23 years) we determined both the inner and the outer orbits using astrometry and radial velocities and measured the mutual orbit inclinations of 11◦.3±1◦.0 and 12◦.0±3◦.0, respectively. Four bright stars are resolved for the first time; two of those are triple systems. Several visual subsystems announced in the literature are shown to be spurious.
    [Show full text]
  • The Near-Infrared Multi-Band Ultraprecise Spectroimager for SOFIA
    NIMBUS: The Near-Infrared Multi-Band Ultraprecise Spectroimager for SOFIA Michael W. McElwaina, Avi Mandella, Bruce Woodgatea, David S. Spiegelb, Nikku Madhusudhanc, Edward Amatuccia, Cullen Blaked, Jason Budinoffa, Adam Burgassere, Adam Burrowsd, Mark Clampina, Charlie Conroyf, L. Drake Demingg, Edward Dunhamh, Roger Foltza, Qian Gonga, Heather Knutsoni, Theodore Muencha, Ruth Murray-Clayf, Hume Peabodya, Bernard Rauschera, Stephen A. Rineharta, Geronimo Villanuevaj aNASA Goddard Space Flight Center, Greenbelt, MD, USA; bInstitute for Advanced Study, Princeton, NJ, USA; cYale University, New Haven, CT, USA; dPrinceton University, Princeton, NJ, USA; eUniversity of California, San Diego, La Jolla, CA, USA; fHarvard-Smithsonian Center for Astrophysics, Cambridge, MA, USA; gUniversity of Maryland, College Park, MD, USA; hLowell Observatory, Flagstaff, AZ, USA; iCalifornia Institute of Technology, Pasadena, CA; jCatholic University of America, Washington, DC, USA. ABSTRACT We present a new and innovative near-infrared multi-band ultraprecise spectroimager (NIMBUS) for SOFIA. This design is capable of characterizing a large sample of extrasolar planet atmospheres by measuring elemental and molecular abundances during primary transit and occultation. This wide-field spectroimager would also provide new insights into Trans-Neptunian Objects (TNO), Solar System occultations, brown dwarf atmospheres, carbon chemistry in globular clusters, chemical gradients in nearby galaxies, and galaxy photometric redshifts. NIMBUS would be the premier ultraprecise
    [Show full text]
  • The Copernican Principle Rules out BLC1 As a Technological Radio Signal from the Alpha Centauri System
    Draft version January 13, 2021 Typeset using LATEX twocolumn style in AASTeX62 The Copernican Principle Rules Out BLC1 as a Technological Radio Signal from the Alpha Centauri System Amir Siraj1 and Abraham Loeb1 1Department of Astronomy, Harvard University, 60 Garden Street, Cambridge, MA 02138, USA ABSTRACT Without evidence for occupying a special time or location, we should not assume that we inhabit privileged circumstances in the Universe. As a result, within the context of all Earth-like planets orbiting Sun-like stars, the origin of a technological civilization on Earth should be considered a single outcome of a random process. We show that in such a Copernican framework, which is inherently optimistic about the prevalence of life in the Universe, the likelihood of the nearest star system, Alpha Centauri, hosting a radio-transmitting civilization is ∼ 10−8. This rules out, a priori, Breakthrough Listen Candidate 1 (BLC1) as a technological radio signal from the Alpha Centauri system, as such a scenario would violate the Copernican principle by about eight orders of magnitude. We also show that the Copernican principle is consistent with the vast majority of Fast Radio Bursts being natural in origin. Keywords: technosignatures; astrobiology; search for extraterrestrial intelligence; biosignatures 1. INTRODUCTION lihood of searches for primitive and intelligent life, us- The Copernican principle asserts that we are not priv- ing a Drake-type approach. Westby & Conselice(2020) ileged observers of the Universe. Successes of its appli- applied the Copernican principle to the search for intel- cation include the rejection of Ptolemaic geocentrism ligent life, but in forms that featured strict boundaries and the adoption of the modern cosmological princi- in time, thereby not reflecting a truly random process.
    [Show full text]
  • YETI – Search for Young Transiting Planets
    YETI – search for young transiting planets Ronny Errmann, Astrophysikalisches Institut und Universitäts-Sternwarte Jena, in collaboration with: Ralph Neuhäuser, AIU Jena Gracjan Maciejewski, Centre for Astronomy of the Nicolaus Copernicus University Ronald Redmer, University of Rostock Martin Seeliger, AIU Jena YETI Observers, all over the world Mercury transit Hot Planets and Cool Stars 8. Nov. 06 (SOHO) Garching 12. November 2012 Venus transit 6. June 12 Motivation youngest transiting planets: ●Corot 2: 130 – 500 Myr (from star spots) 30 – 40 Myr (from planet radius) ●Corot 20: 100 – 800 Myr (from Li-abundance) M = 1 MJup ●Wasp 10: 200 – 350 Myr (from gyro-chronology) → younger transiting planets (Radius+true Mass) needed, to test models, and planet formation scenarios Observation strategies increase probability for transiting planet: monitoring of many young stars -> Young open clusters orbital periods: ~1 to ~10 days transit duration: ~1 to few hours → 1 to 5% of orbit in transit phase observation with single telescope: data gaps because of daytime, weather, ... increase probability for observing transit signal: long continuous observation -> YETI YETI-network (Young Exoplanet Transit Initiative) Tenagra II Llano del Gettysburg Sierra Nevada Jena Stara Lesna Byurakan Xinglong Gunma Hato Astrophysical 0.8-m telescope Observatory Collage Astronomical 1.0 and 2.6 Observatory Astronomical 1.5-m telescope Institute Observatory Institute telescopes 90/60 cm Observatory 0.9/0.6-m 0.6-m telescope 1.5-m telescope 1-m Schmidt 0.4-m telescope
    [Show full text]
  • Download This Article in PDF Format
    A&A 562, A92 (2014) Astronomy DOI: 10.1051/0004-6361/201321493 & c ESO 2014 Astrophysics Li depletion in solar analogues with exoplanets Extending the sample, E. Delgado Mena1,G.Israelian2,3, J. I. González Hernández2,3,S.G.Sousa1,2,4, A. Mortier1,4,N.C.Santos1,4, V. Zh. Adibekyan1, J. Fernandes5, R. Rebolo2,3,6,S.Udry7, and M. Mayor7 1 Centro de Astrofísica, Universidade do Porto, Rua das Estrelas, 4150-762 Porto, Portugal e-mail: [email protected] 2 Instituto de Astrofísica de Canarias, C/ Via Lactea s/n, 38200 La Laguna, Tenerife, Spain 3 Departamento de Astrofísica, Universidad de La Laguna, 38205 La Laguna, Tenerife, Spain 4 Departamento de Física e Astronomia, Faculdade de Ciências, Universidade do Porto, 4169-007 Porto, Portugal 5 CGUC, Department of Mathematics and Astronomical Observatory, University of Coimbra, 3049 Coimbra, Portugal 6 Consejo Superior de Investigaciones Científicas, CSIC, Spain 7 Observatoire de Genève, Université de Genève, 51 ch. des Maillettes, 1290 Sauverny, Switzerland Received 18 March 2013 / Accepted 25 November 2013 ABSTRACT Aims. We want to study the effects of the formation of planets and planetary systems on the atmospheric Li abundance of planet host stars. Methods. In this work we present new determinations of lithium abundances for 326 main sequence stars with and without planets in the Teff range 5600–5900 K. The 277 stars come from the HARPS sample, the remaining targets were observed with a variety of high-resolution spectrographs. Results. We confirm significant differences in the Li distribution of solar twins (Teff = T ± 80 K, log g = log g ± 0.2and[Fe/H] = [Fe/H] ±0.2): the full sample of planet host stars (22) shows Li average values lower than “single” stars with no detected planets (60).
    [Show full text]
  • Arxiv:2105.11583V2 [Astro-Ph.EP] 2 Jul 2021 Keck-HIRES, APF-Levy, and Lick-Hamilton Spectrographs
    Draft version July 6, 2021 Typeset using LATEX twocolumn style in AASTeX63 The California Legacy Survey I. A Catalog of 178 Planets from Precision Radial Velocity Monitoring of 719 Nearby Stars over Three Decades Lee J. Rosenthal,1 Benjamin J. Fulton,1, 2 Lea A. Hirsch,3 Howard T. Isaacson,4 Andrew W. Howard,1 Cayla M. Dedrick,5, 6 Ilya A. Sherstyuk,1 Sarah C. Blunt,1, 7 Erik A. Petigura,8 Heather A. Knutson,9 Aida Behmard,9, 7 Ashley Chontos,10, 7 Justin R. Crepp,11 Ian J. M. Crossfield,12 Paul A. Dalba,13, 14 Debra A. Fischer,15 Gregory W. Henry,16 Stephen R. Kane,13 Molly Kosiarek,17, 7 Geoffrey W. Marcy,1, 7 Ryan A. Rubenzahl,1, 7 Lauren M. Weiss,10 and Jason T. Wright18, 19, 20 1Cahill Center for Astronomy & Astrophysics, California Institute of Technology, Pasadena, CA 91125, USA 2IPAC-NASA Exoplanet Science Institute, Pasadena, CA 91125, USA 3Kavli Institute for Particle Astrophysics and Cosmology, Stanford University, Stanford, CA 94305, USA 4Department of Astronomy, University of California Berkeley, Berkeley, CA 94720, USA 5Cahill Center for Astronomy & Astrophysics, California Institute of Technology, Pasadena, CA 91125, USA 6Department of Astronomy & Astrophysics, The Pennsylvania State University, 525 Davey Lab, University Park, PA 16802, USA 7NSF Graduate Research Fellow 8Department of Physics & Astronomy, University of California Los Angeles, Los Angeles, CA 90095, USA 9Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125, USA 10Institute for Astronomy, University of Hawai`i,
    [Show full text]
  • Fy10 Budget by Program
    AURA/NOAO FISCAL YEAR ANNUAL REPORT FY 2010 Revised Submitted to the National Science Foundation March 16, 2011 This image, aimed toward the southern celestial pole atop the CTIO Blanco 4-m telescope, shows the Large and Small Magellanic Clouds, the Milky Way (Carinae Region) and the Coal Sack (dark area, close to the Southern Crux). The 33 “written” on the Schmidt Telescope dome using a green laser pointer during the two-minute exposure commemorates the rescue effort of 33 miners trapped for 69 days almost 700 m underground in the San Jose mine in northern Chile. The image was taken while the rescue was in progress on 13 October 2010, at 3:30 am Chilean Daylight Saving time. Image Credit: Arturo Gomez/CTIO/NOAO/AURA/NSF National Optical Astronomy Observatory Fiscal Year Annual Report for FY 2010 Revised (October 1, 2009 – September 30, 2010) Submitted to the National Science Foundation Pursuant to Cooperative Support Agreement No. AST-0950945 March 16, 2011 Table of Contents MISSION SYNOPSIS ............................................................................................................ IV 1 EXECUTIVE SUMMARY ................................................................................................ 1 2 NOAO ACCOMPLISHMENTS ....................................................................................... 2 2.1 Achievements ..................................................................................................... 2 2.2 Status of Vision and Goals ................................................................................
    [Show full text]
  • View of the Interior Structure
    UNIVERSITY OF CINCINNATI Date: 17-Sep-2010 I, Benjamin Frank Bubnick , hereby submit this original work as part of the requirements for the degree of: Master of Science in Physics It is entitled: Massive Stellar Clusters in the Disk of the Milky Way Galaxy Student Signature: Benjamin Frank Bubnick This work and its defense approved by: Committee Chair: Margaret Hanson, PhD Margaret Hanson, PhD 10/4/2010 1,102 Massive Stellar Clusters in the Disk of the Milky Way Galaxy A Thesis submitted to the Graduate School of the University of Cincinnati in partial fulfillment of the requirements for the degree of Master of Science in the Department of Physics of the College of Arts and Sciences 2010 by Benjamin Bubnick Committee Chair: Margaret Hanson ABSTRACT Title of thesis: Massive Stellar Clusters in the Disk Of the Milky Way Galaxy Benjamin Bubnick, Master of Science, 2010 Thesis directed by: Professor Margaret Hanson Department of Physics This thesis outlines successful efforts for identifying and characterizing the stellar content of two Galactic disk star clusters using near-infrared observations. Astronomers have a great wealth of knowledge about globular clusters. They are easy to see as most lie outside the plane of the galaxy in the halo. Extinction is low, the stellar population is dense in the cluster, and they are fairly common. However, in the plane of the galaxy, relatively little is known of the open cluster population. Galactic disk open clusters, such as the two discussed in this thesis, are hidden behind gas, dust, and projected against a multitude of field stars.
    [Show full text]
  • A Method of Correcting Near-Infrared Spectra for Telluric Absorption1
    Publications of the Astronomical Society of the Pacific, 115:389–409, 2003 March ᭧ 2003. The Astronomical Society of the Pacific. All rights reserved. Printed in U.S.A. A Method of Correcting Near-Infrared Spectra for Telluric Absorption1 William D. Vacca,2 Michael C. Cushing, and John T. Rayner Institute for Astronomy, University of Hawaii, Honolulu, HI 96822; [email protected], [email protected], [email protected] Received 2002 October 29; accepted 2002 November 8 ABSTRACT. We present a method for correcting near-infrared medium-resolution spectra for telluric absorption. The method makes use of a spectrum of an A0 V star, observed near in time and close in air mass to the target object, and a high-resolution model of Vega, to construct a telluric correction spectrum that is free of stellar absorption features. The technique was designed specifically to perform telluric corrections on spectra obtained with SpeX, a 0.8–5.5 mm medium-resolution cross-dispersed spectrograph at the NASA Infrared Telescope Facility, and uses the fact that for medium resolutions there exist spectral regions uncontaminated by atmospheric absorption lines. However, it is also applicable (in a somewhat modified form) to spectra obtained with other near-infrared spectrographs. An IDL-based code that carries out the procedures is available for downloading via the World Wide Web. 1. INTRODUCTION are designed to study the H lines in the spectrum of the object Ground-based near-infrared spectroscopy (∼1–5 mm) has of interest. One technique commonly adopted in order to pre- always been hampered by the strong and variable absorption serve the other desirable qualities of A stars as telluric and flux features due to the Earth’s atmosphere.
    [Show full text]
  • Searching For, Finding, and Imaging Young Extrasolar Planets with HST
    Searching for, Finding, and Imaging Young Extrasolar Planets with HST/NICMOS 2MASSWJ 1207-334-393254b (2M1207b): A Common Proper Motion Companion of Planetary Mass to a Young Brown Dwarf G. Schneider (Steward Obs., UofA), I. Song, J. Farihi, (Gemini Obs.), B. Zuckerman, E. Becklin (UCLA), P. Lowrance (Caltech), B. Macintosh (LLNL), M. Bessell (ANU) ABSTRACT: Imaging discovery and subsequent characterization of extrasolar planet NICMOS CORONAGRAPHY DETECTION LIMITS & UNCERTAINTIES (EP) mass companions to stars has been observationally challenging due to the severe planet-to-star contrast ratios. Since the detection of the extrasolar giant planet (EGP) The ability to detect faint point sources near bright objects (e.g., planetary mass SINGLE ORBIT observations which roll the telescope about the target axis companion to 51 Peg [1], continuing discoveries of 1 – 10 Jupiter mass companions by companions to stars) is instrumentally enhanced by reducing the brightness of the (unfortunately, technically unfeasible with HST's soon to be implemented two-gyro indirect methods have revealed an unanticipated diversity in mass ranges, dynamical central star. To enable such observations, HST has provided unique resources for high guiding mode) are highly efficient and permit optimal self-subtraction of the properties, and primary-star characteristics. The past decade has seen an explosion of contrast imaging with its panchromatic complement of coronagraphically augmented underlying coronagraphic point-spread function. Such observations yield total indirect detections of EGP companions to solar-like stars through radial velocity imagers: NICMOS (near-IR), ACS (UV/Optical) and, until recently, STIS (broadband integration times of, typically, ~ 1300s. Highly repeatable point source detection limits surveys [2] and more recently, in much smaller numbers, via photometric transits [e.g., Optical).
    [Show full text]
  • Stellar Population Synthesis Models Between 2.5 and 5Μm Based on The
    MNRAS 449, 2853–2874 (2015) doi:10.1093/mnras/stv503 Stellar population synthesis models between 2.5 and 5 µm based on the empirical IRTF stellar library B. Rock,¨ 1,2‹ A. Vazdekis,1,2‹ R. F. Peletier,3‹ J. H. Knapen1,2 and J. Falcon-Barroso´ 1,2 1Instituto de Astrof´ısica de Canarias, V´ıa Calle Lactea,´ E-38205 La Laguna, Tenerife, Spain 2Departamento de Astrof´ısica, Universidad de La Laguna, E-38205 La Laguna, Tenerife, Spain 3Kapteyn Astronomical Institute, University of Groningen, Postbus 800, NL-9700 AV Groningen, the Netherlands Downloaded from https://academic.oup.com/mnras/article/449/3/2853/2893016 by guest on 27 September 2021 Accepted 2015 March 5. Received 2014 December 21; in original form 2014 July 23 ABSTRACT We present the first single-burst stellar population models in the infrared wavelength range between 2.5 and 5 µm which are exclusively based on empirical stellar spectra. Our models take as input 180 spectra from the stellar IRTF (Infrared Telescope Facility) library. Our final single-burst stellar population models are calculated based on two different sets of isochrones and various types of initial mass functions of different slopes, ages larger than 1 Gyr and metallicities between [Fe/H] =−0.70 and 0.26. They are made available online to the scien- tific community on the MILES web page. We analyse the behaviour of the Spitzer [3.6]−[4.5] colour calculated from our single stellar population models and find only slight dependences on both metallicity and age. When comparing to the colours of observed early-type galaxies, we find a good agreement for older, more massive galaxies that resemble a single-burst popu- lation.
    [Show full text]