2018 Annual Report

Total Page:16

File Type:pdf, Size:1020Kb

2018 Annual Report 2018 ANNUALREPORT 18 TABLEOFCONTENTS20 1 Trustee’s Update 2 Director’s Update 3 Astronomy Article 7 Science Highlights 30 Technical Support Highlights 33 Development Highlights 35 Public Program Highlights 38 Putnam Collection Center Highlights 40 Communication Highlights 42 Volunteer Highlights 43 Peer-Reviewed Publications 52 Conference Proceedings & Abstracts 61 Statement of Financial Position TRUSTEE’SUPDATE By W. Lowell Putnam While this report is about 2018, facilities. Thanks to great support from it is published in 2019 on the 125th our donors we will be opening the anniversary of the observatory, so a Giovale Open Deck Observatory as certain amount of reflection is expected. well as adding increased parking, more As you will see is looking through storage, and improved traffic flow… this document, Lowell Observatory with more to come in the next few is continuing to follow the mission years. established by our founder, and the In looking back through our archives current staff are doing an excellent job for this milestone year we came across scientifically and in public outreach. the original seal that Percival used in Supporting those individuals are other publications about research work done hard working groups in technology, at Lowell. There will be a full story operations and development. All about that later, but the Latin motto of them contribute to making this Percival chose for the seal translates institution the success it is today, and all as “Worlds Revealed”. As you look that success is built on the hard work through the science articles noted and efforts of those in prior years all in the following pages, you will see the way back to 1894. that works continues to this day, and We are also looking forward to the increasing success of our public what 2019 has to offer. If you come to programs allows us to help reveal that our main campus on Mars Hill you will work to new guests and generations. see major changes. With over 105,000 Thank you for supporting all this visitors last year we have gone well great work! ■ beyond the capacity of our current Lowell Observatory | 2018 ANNUALREPORT | Trustee’s Update 1 DIRECTOR’SUPDATE By Jeffrey Hall Perchance, I am writing this note for Federal support for science and basic our annual report on the morning of R&D seems increasingly deprioritized, May 28, 2019—125 years to the day private-sector support again comes after Percival Lowell stepped off a train to the fore. The Discovery Channel in the frontier hamlet of Flagstaff and Telescope and its instrument cube made his way up Mars Hill to found the were built entirely with private funds. observatory that bears his name. The Astronomy Discovery Center will Looking out my office window on be substantially or entirely privately- this clear and sunny morning, I can funded as well. With these facilities, see the Clark Telescope dome not far we strive to learn more about the up the hill, where Percival spent many Universe of which we are a part, and nights making meticulous maps of we return our supporters’ investment by Mars. communicating the wonder, the power, A few decades later, Clyde and the fun of science to all. Tombaugh walked into the very office Lowell, Yerkes, Lick, and Carnegie where I am now sitting and said to no doubt understood that this is much then-Director V. M. Slipher, with what more than doing well by doing good. must have been quivering excitement, “I It is a national and ethical imperative, have found your Planet X.” for we are retreating today into almost Quite a few decades after that, medieval superstition. Climate change Trustee William Lowell Putnam, III is a hoax. Vaccines cause autism. Cell and Director Bob Millis committed the tower emissions will kill you. Planes observatory to remain a vital institution spray chemtrails. Evolution is “just a of research, starting us down a 20- theory.” There are canals of intelligent year, $53 million road that would lead construction on Mars. No, no, no; no, to the construction and commissioning no, and no. All of those statements face of the 4.3-meter Discovery Channel overwhelming evidence indicating they Telescope. are false. But increasingly, evidence A few weeks ago, the observatory’s and data no longer matter; perception management team and I met to discuss and Internet trolling are the order of the project and cost management of our day. next massive undertaking, the $35 Everything you’ll read in these million Astronomy Discovery Center. pages is part of our commitment to One hundred and twenty five performing and communicating real years is a long time, and a lot has science, both in our research as well as changed on Mars Hill. But as we our outreach. Here at Percival Lowell’s begin our second 125 years, I see observatory, we would be failing our not just change but an opportunity founder to do any less. Percival was that begins anew a cycle of discovery wrong about Mars, and that’s OK: he and inspiration. The fin de siècle era inspired generations of scientists to when that train arrived in Flagstaff was learn more about the true nature of our one when a number of private-sector neighbor planet, and that’s how science visionaries and philanthropists like works. As we begin our second 125 Percival Lowell, Charles Yerkes, James years, we’ll use the Discovery Channel Lick, and Andrew Carnegie devoted Telescope and, soon, the Astronomy their energy and their fortunes to the Discovery Center to continue to explore advancement of science. Their vision our weird and wondrous Universe, and led to the creation of several great to promote to the greatest extent we observatories that pushed forward the can the rational, data-driven thinking national frontier of astronomy and and decision-making our technical inspired generations to come. Today, as society must have. ■ Lowell Observatory | 2018 ANNUALREPORT | Director’s Update 2 John Hendricks proposed what A unique history MEET THE RESEARCHERS AT LOWELL would become a $16 million Lowell Observatory’s story gift to commence the 4.3-meter begins with Percival Lowell Deputy Director for Science Michael West is a searching for exoplanetary magnetic fields and (1855–1916), part of the famous longtime galaxy expert whose research interests understanding how they may shield a planet from Discovery Channel Telescope include star clusters, galaxy formation and evolu- overpowering radiation. (DCT), the largest and most America’s observatory Lowell family of Boston. Percival graduated from tion, clusters of galaxies, and the large-scale struc- Phil Massey is the principal investigator for the sophisticated telescope in RIGHT: The refurbished and ture of the cosmos. He is also very active in Large Monolithic Imager, the primary optical camera northern Arizona. rededicated Pluto Telescope Harvard University and MIT, astronomy education and outreach, as well as on the Discovery Channel Telescope. He is interested The DCT completely gleams in its dome in June 2018. and he spent his younger days promotion of dark skies. in studying massive stars, binary stars, young star reworked Lowell and sent the running the family business BELOW: In Lowell’s Collection Astronomer George Jacoby, former deputy clusters, and the young stars in nearby galaxies to organization into a more mod- based in Lowell and Lawrence, director for technology, is an expert on planetary understand how the most luminous stars evolve. Center, you can see the Slipher ern, more complex era of oper- Spectrograph, with which V.M. enters a new age Massachusetts. Keenly inter- nebulae who spent most of his career at the Focusing on the solar system, Michael Mommert National Optical Astronomy Observatory in Tucson. is chiefly absorbed with studying the physical ations, one that depends on a Slipher discovered the expansion ested in science from his youth, committed staff of around 120 of the universe and the existence however, he was especially Jacoby, who retired last fall, also conducted a great properties of asteroids and comets. He observes of the interstellar medium. deal of research at Kitt Peak National Observatory, these objects in wavelengths ranging from optical employees and many hard- In the January 2019 issue of attracted to the mystery of where he served as director of WIYN Observatory. to near-infrared to help unravel their compositions, working volunteers. The DCT RIGHT: Clyde Tombaugh’s son Astronomy magazine, editor Mars. In 1894, he set about Ted Dunham, who also retired last fall, was masses, reflectivities, rotational properties, and saw first light in 2015 and has and daughter, Alden and Annette (and Lowell Observatory establishing his childhood responsible for astronomical instrumentation devel- overall shapes. Tombaugh, stand next to the Pluto been a workhorse ever since. dream: building an observatory oped at Lowell Observatory. His research centered Also highly interested in small solar system Telescope, with which their father Advisory Board member) on stellar occultations by planets in the solar system, objects is Nick Moskovitz, who studies asteroids The DCT is by no means all discovered Pluto in 1930. Dave Eicher wrote an dedicated to studying Mars and using observations made aboard the airborne using observations and modeling. His work focuses of Lowell’s science activities. outstanding article about other phenomena. observatory SOFIA. on collecting data to understand the link between Some 12 miles (19 kilometers) “America’s Observatory”, Lowell chose what would be Members of the Lowell, Putnam, Tombaugh, Sykes, Slipher, and Christy families stand in front of the rededicated Focusing on icy outer solar system objects, asteroids and meteorites, the origins of asteroid southwest of Flagstaff stands as he calls Lowell. With called Mars Hill in Flagstaff Pluto Telescope on Mars Hill during a historic gathering last June.
Recommended publications
  • Astro2020 APC White Papers the Navy Precision Optical Interferometer
    Astro2020 APC White Papers The Navy Precision Optical Interferometer Type of Activity: Ground Based Project Space Based Project Infrastructure Activity 4 Technological Development Activity State of the Professions Consideration4 Other Principal Author: Name: Gerard van Belle Institution: Lowell Observatory Email: [email protected] Phone: 928-255-7865 Co-authors: (names, institutions, emails) J. Thomas Armstrong (NRL, [email protected]), Ellyn Baines (NRL, [email protected]), Joe Llama (Lowell, [email protected]), Henrique Schmitt (NRL, [email protected]) Abstract: The Navy Precision Optical Interferometer (NPOI) is one of the premier U.S. long-baseline optical interferometric facilities, capable of providing sub-milliarcsecond imaging in the visible. We outline a plan for NPOI for 2020-2030 that will cement its leadership as the highest resolution optical system on the planet, with multi-kilometer baselines. This capability will serve a wide variety of Astro2020 science needs, resolving the sizes and shapes of stars, resolving AGNs, imaging protoplanetary disks, and observing the passage of exoplanets across their stellar disks. 1 1 Introduction The Navy Precision Optical Interferometer (NPOI), a long baseline optical interferometer located on Anderson Mesa, near Flagstaff, Arizona, is operated as a partnership between Lowell Observatory, the Naval Research Laboratory (NRL), and the US Naval Observatory (USNO). It features a Y-shaped layout with 250 m arms, telescopes that can be moved among 30 stations along the arms, visible-band beam combiners, and a vacuum feed system to avoid ground seeing and differential longitudinal dispersion. NPOI currently operates with up to six telescopes simultaneously feeding the beam combination laboratory with 12-cm effective apertures, on baselines (separations between the apertures) up to 98-m.
    [Show full text]
  • Programme Book
    SANTANDER INTERNATIONAL SUMMER SCHOOLS FOR DOCTORAL STUDENTS REACHING THE LIMITS OF THE SKY ASTRONOMICAL INSTRUMENTATION IN THE 21ST CENTURY PROGRAMME BOOK NOVEMBER 17 TO 28, 2014 HEIDELBERG CENTER FOR LATIN AMERICA (HCLA), SANTIAGO DE CHILE COOPERATION PARTNERS Pontificia Universidad Católica de Chile (PUC) Planetarium – Universidad de Santiago de Chile (USACH) ESO Vitacura Office ESO Observatory Cerro Paranal SANTANDER INTERNATIONAL SUMMER SCHOOLS FOR DOCTORAL STUDENTS REACHING THE LIMITS OF THE SKY ASTRONOMICAL INSTRUMENTATION IN THE 21ST CENTURY CONTENT Universität Heidelberg 5 Santander Universidades 5 Programme Overview 7 Detailed Programme 8 Coordinators 14 Speakers 15 Doctoral Students 17 Abstracts of Summer School Speakers 18 Abstracts of Symposium Speakers 26 Description of Doctoral Projects 28 Venues 34 4/ SANTANDER Summer School 2014 Programme Book Thema des Kapitels Universität Heidelberg, University Square UNIVERSITÄT HEIDELBERG Heidelberg University, founded in 1386, is Germany’s old- International Profile est university and one of the strongest research universities Heidelberg University is tied into a worldwide network of re- in Europe. The successes in both rounds of the Excellence search and teaching collaborations. Exchange programmes Initiative of the German federal and state governments have been established with more than 400 universities and in international rankings prove its leading role in the worldwide. Heidelberg’s marked global interconnectedness scientific community. In terms of educating students and is also evidenced by its 19 university partnerships and promoting promising young academics, Heidelberg relies three International Research Training Groups as well as its on research-based teaching and a well-structured training membership in European networks such as the League of for doctoral candidates.
    [Show full text]
  • Fundamental Stellar Parameters
    Astro2020 Science White Paper High Angular Resolution Astrophysics: Fundamental Stellar Parameters Thematic Areas: Planetary Systems Star and Planet Formation Formation and Evolution of Compact Objects Cosmology and Fundamental Physics 3Stars and Stellar Evolution Resolved Stellar Populations and their Environments Galaxy Evolution Multi-Messenger Astronomy and Astrophysics Principal Author: Name: Gerard van Belle Institution: Lowell Observatory Email: [email protected] Phone: 928-233-3207 Co-authors: (names and institutions) Ellyn Baines, Naval Research Laboratory Tabetha Boyajian, Louisiana State University Doug Gies, Georgia State University Jeremy Jones, Georgia State University John Monnier, University of Michigan Ryan Norris, Georgia State University Rachael Roettenbacher, Yale University Theo ten Brummelaar, Georgia State University Kaspar von Braun, Lowell Observatory Russel White, Georgia State University Abstract: Direct determination of fundamental stellar parameters has many profound and wide-ranging impacts throughout astrophysics. These determinations are rooted in high angular resolution observations. In particular, as long-baseline optical interferometry has matured over the past decade, increasingly large survey samples are serving to empirically ground the basic parameters of these building blocks of the universe. True imaging and improved parametric fitting are becoming routinely available, an essential component of fully characterizing stars, stellar environments, and planets these stars may host. 1 1 Fundamental Stellar Parameters There are about a trillion stars in the Milky Way. Some are single, some are bound in hierarchical systems, perhaps members of star clusters, but it is readily apparent that the parent star or parent stars of every stellar system dominates the system in multiple, fundamental ways. First, stars will be the principal mass repository in the system, which may additionally contain planets, dust, and gas.
    [Show full text]
  • Lowell Observatory Issue 92 Fall 2011 from Discovering to Describing Near-Earth Asteroids by Tom Vitron
    LOWELL EXPANDING OUR UNIVERSE OBSERVER The quarterly newsletter of Lowell Observatory Issue 92 Fall 2011 From Discovering to Describing Near-Earth Asteroids by Tom Vitron When the Lowell Observatory Near-Earth Object Search (LONEOS) Asteroids like Ida can have small companion moons like Dactyl (right). Discovering companions is one came to a close in 2008, it did not of the tasks for NEAPS researchers. (Photo courtesy: NASA/JPL) mark the end of near-Earth object research at Lowell. Rather, it marked a With the 24-inch Schmidt Telescope project’s main data output. However, shift from discovering these objects to as the workhorse instrument, research more work is required before robust characterizing them. “[Dr. Ted Bowell] assistant Brian Skiff and other observers statistics about NEA rotation can be opted to use our resources to study one generated a lot of data over the course compiled. of the physical properties of near-Earth of the project. For example, one of the Since this research does not require asteroids (NEAs): rotational period,” most challenging asteroids observed by the biggest, most modern telescopes, says Dr. Bruce Koehn, who recently NEAPS was 2011 AL37. This asteroid amateur astronomers are participating in took the reigns from Dr. Bowell (see closely approached Earth on January asteroid research. “Their data, combined article on page 5) and is the principal 26, 2011 and was moving at almost with ours, will likely make a very good investigator to LONEOS’s successor, the 60 degrees per day. Fortunately, it was data set,” says Dr. Koehn. “We have Near-Earth Asteroid Photometric Survey bright enough that Skiff took short made a significant contribution to the (NEAPS).
    [Show full text]
  • PRESS RELEASE for IMMEDIATE RELEASE May 2, 2017 ***Contact
    PRESS RELEASE FOR IMMEDIATE RELEASE May 2, 2017 ***Contact details appear below*** ***Text and images https://lowell.edu/category/news/*** LOWELL OBSERVATORY TO LEAD $3.25-MILLION PROJECT TO UPGRADE TELESCOPE ARRAY Flagstaff, AZ. – The Naval Research Laboratory (NRL) has awarded $3,269,000 to Lowell Observatory to upgrade the Navy Precision Optical Interferometer (NPOI) in Flagstaff, Arizona. This will support a project aimed at developing advanced techniques for high-resolution imaging. The improved imaging capability will be applied to astrophysical targets, which will result in new revelations about the nature of extrasolar planets, stellar surface imaging, and the shapes and structures of asteroids. The NPOI upgrade consists of the addition of three 1.0-meter PlaneWave telescopes. In parallel with this initial 24-month facility upgrade period, a five-year program for the development of advanced techniques for the facility will potentially raise the total grant amount to over $7 million. Lowell operates the NPOI in partnership with NRL and the U.S. Naval Observatory (USNO). It is an advanced telescope array which links multiple optical telescopes together to form a single, larger synthetic telescope. This technique delivers spatial resolution – the ability for a telescope to ‘zoom’ and pick out fine detail – greater than any single traditional telescope can provide. Lowell Observatory’s Dr. Gerard van Belle heads the project, nicknamed PALANTIR (Precision Array of Large-Aperture New Telescopes for Image Reconstruction; the name also pays homage to the far-seeing stones in Lord of the Rings). He said, “By combining the already powerful capacity of the NPOI with the new PlaneWave telescopes, we can expect to see an increase of light-gathering capability by a factor of 70 times, enabling detailed observations of significantly fainter objects.” Lowell will work in conjunction with the NRL on the project.
    [Show full text]
  • An Evaluation of Magnetic Bode's Law for Extrasolar Planetary Systems Sânzia Alves (UFRN, Brazil)
    An Evaluation of Magnetic Bode's law for Extrasolar Planetary Systems Sânzia Alves (UFRN, Brazil) Quantitative stellar spectral classification Matthias Ammler-von Eiff (Thueringer Landessternwarte, Tautenburg, Germany) Detection of Occultation by a Proto-planetary Clump in the Habitable Zone in GM Cephei Wen-Ping Chen (National Central University, Taiwan) Status of the Visible Nulling Coronagraph Technology Demonstration Program Mark Clampin (NASA/GSFC) Characterizing Extrasolar planets with WIRCam at CFHT Daniel Devost (Canada-France-Hawaii Telescope) The missing cavities in the SEEDS polarized scattered light images of transitional protoplanetary disks: a new transitional disk model Ruobing Dong (Princeton University) The azimuthal distribution of dusts in an eccentric proto-planetary disk with an embedded gas giant planet Pin-Gao Gu (Institute of Astronomy & Astrophysics, Academia Sinica Taiwan) Water vapor observations in the atmospheres of Earth and Mars Paul Hartogh (null, Germany) Benefits of ultraviolet and near-IR spectra in characterizing habitable planets Sara Heap (NASA's Goddard Space Flight Center) Habitable planets – problems and opportunities Alisher HOJAEV (National University of Uzbekistan) Stability of Giant Planet Moons in Planet-Planet Scattering Events Yu-Cian Hong (Astronomy and Space Science, Cornell University) Simulator for Microlens Planet Surveys Sergei Ipatov (Alsubai Est. for Scientific Studies, Doha, Qatar) The Transit Observations and Orbital Configurations of TrES3 and WASP10 Planetary Systems Ing-Guey
    [Show full text]
  • Community Access for Long Baseline Optical/Infrared Interferometry
    Community Access for Long Baseline Optical/Infrared Interferometry Gail H. Schaefer (CHARA, Georgia State University), Theo ten Brummelaar (CHARA, GSU), Gerard van Belle (Lowell Observatory), Michelle Creech-Eakman (New Mexico Tech, MRO), Douglas Gies (CHARA, GSU), and Stephen Ridgway (NOAO) Long baseline optical/infrared interferometry (LBOI) provides a milliarcsecond view of the universe. The technique of LBOI is used to investigate a wide range of topics in stellar astrophysics involving high spatial resolution studies of stars and their circumstellar environments. Open access time to interferometers is moving LBOI into the mainstream of astronomical techniques. Continued support of open access time through NOAO into the next decade will expand the scientific productivity of U.S.- based interferometric arrays. This access will also help optimize the science return from large scale ground and space-based surveys by following up targets of interest discovered by these missions. Access to existing infrastructure will aid the development of technologies necessary for building the next generation of astronomical observatories that will push the limits on sensitivity and spatial resolution. Science at Milliarcsecond Resolution – Resolving the size, shape, and surface features of nearby stars provides a detailed understanding of stellar structure and evolution that can be applied to our understanding of the global properties of distant populations. Over 700 refereed science publications based on results from LBOI have appeared over the last two decades. The main science topics include: ● Measuring radii and effective temperatures of stars across the H-R diagram. ● Investigating the impact of rotation on stellar structure (oblateness, gravity darkening). ● Imaging spots and convection patterns on the surfaces of stars.
    [Show full text]
  • Lowellobserver
    THE ISSUE 112 WINTER 2017 LOWELL OBSERVER THE QUARTERLY NEWSLETTER OF LOWELL OBSERVATORY HOME OF PLUTO Lowell Observatory engineers Frank Cornelius and Ben Hardesty hoist the EXPRES vacuum enclosure. IN THIS ISSUE 2 Director’s Update 2 Trustee’s Update 3 Gerard van Belle Heads NPOI EXPRES By Debra Fischer, Yale University EXPRES is the EXtreme PREcision and acquisition system, new targets 4 Giovale Open Deck Observatory Spectrograph. Designed and built at always fell within a 10” radius of the Yale University, this will be the first fiber. David Sawyer, who was a system 5 Junior Astronomer Program spectrograph with the precision to detect engineer at Yale before becoming 7 Expanding LOCKs analogs of our Earth around nearby stars. Lowell’s technical project manager, said Lowell Observatory’s Discovery Channel this was the smoothest commissioning Telescope (DCT) is the perfect telescope that he has seen in his 25-year career. for collecting the photons that EXPRES One of the most important will use for exoplanet detection. efforts for extreme precision and the While work on the spectrograph detectability of Earthlike planets is the continued in the Yale Exoplanet Lab this ability to disentangle velocities that summer, the first stage of commissioning arise on the surface of stars from orbital at the DCT was completed, with velocities. We are making exciting installation of the three-ton vacuum progress with new statistical techniques 8 Stephen Riggs Joins Lowell enclosure; the front end module; and using simulated data. The high fidelity 9 The Next Chapter critical software – the data-taking data from EXPRES are critical to the GUI for controlling EXPRES and for successful application of the methods 10 The Lowells’ Love of Plants communicating with the telescope control continued on page 21 11 Dispatches from the Universe system.
    [Show full text]
  • Resolving the Effects of Rotation in Altair with Long-Baseline
    Submitted to the Astrophysical Journal June 9, 2005 Revised draft of June 21, 2018 A Preprint typeset using LTEX style emulateapj v. 6/22/04 RESOLVING THE EFFECTS OF ROTATION IN ALTAIR WITH LONG-BASELINE INTERFEROMETRY D. M. Peterson1, C. A. Hummel2,4, T. A. Pauls3, J. T. Armstrong3, J. A. Benson5, C. G. Gilbreath3, R. B. Hindsley3, D. J. Hutter5, K. J. Johnston4, D. Mozurkewich6, & H. Schmitt3,7 (Received 2005 June 9) Submitted to the Astrophysical Journal June 9, 2005 Revised draft of June 21, 2018 ABSTRACT We report successful fitting of a Roche model, with a surface temperature gradient following the von Zeipel gravity darkening law, to observations of Altair made with the Navy Prototype Optical Interferometer. We confirm the claim by Ohishi, Nordgren, & Hutter that Altair displays an asym- metric intensity distribution due to rotation, the first such detection in an isolated star. Instrumental effects due to the high visible flux of this first magnitude star appear to be the limiting factor in the accuracy of this fit, which nevertheless indicates that Altair is rotating at 0.90 ± 0.02 of its breakup (angular) velocity. Our results are consistent with the apparent oblateness found by van Belle et al. and show that the true oblateness is significantly larger owing to an inclination of the rotational axis of ∼ 64◦ to the line of sight. Of particular interest, we conclude that instead of being substantially evolved as indicated by its classification, A7 VI-V, Altair is only barely off the ZAMS and represents a good example of the difficulties rotation can introduce in the interpretation of this part of the HR diagram.
    [Show full text]
  • Stellar Diameters and Temperatures. I. Main-Sequence A, F, and G Stars
    The Astrophysical Journal, 746:101 (26pp), 2012 February 10 doi:10.1088/0004-637X/746/1/101 C 2012. The American Astronomical Society. All rights reserved. Printed in the U.S.A. STELLAR DIAMETERS AND TEMPERATURES. I. MAIN-SEQUENCE A, F, AND G STARS Tabetha S. Boyajian1,6, Harold A. McAlister1, Gerard van Belle2, Douglas R. Gies1, Theo A. ten Brummelaar3, Kaspar von Braun4, Chris Farrington3, P. J. Goldfinger3, David O’Brien1, J. Robert Parks1, Noel D. Richardson1, Stephen Ridgway5, Gail Schaefer3, Laszlo Sturmann3, Judit Sturmann3, Yamina Touhami1, Nils H. Turner3, and Russel White1 1 Center for High Angular Resolution Astronomy and Department of Physics and Astronomy, Georgia State University, Atlanta, GA 30302-4106, USA 2 Lowell Observatory, Flagstaff, AZ 86001, USA 3 The CHARA Array, Mount Wilson Observatory, Mount Wilson, CA 91023, USA 4 NASA Exoplanet Science Institute, California Institute of Technology, MC 100-22, Pasadena, CA 91125, USA 5 National Optical Astronomy Observatory, Tucson, AZ 85726-6732, USA Received 2011 October 28; accepted 2011 December 14; published 2012 January 27 ABSTRACT We have executed a survey of nearby, main-sequence A-, F-, and G-type stars with the CHARA Array, successfully measuring the angular diameters of forty-four stars with an average precision of ∼1.5%. We present new measures of the bolometric flux, which in turn leads to an empirical determination of the effective temperature for the stars observed. In addition, these CHARA-determined temperatures, radii, and luminosities are fit to Yonsei–Yale model isochrones to constrain the masses and ages of the stars. These results are compared to indirect estimates of these quantities obtained by collecting photometry of the stars and applying them to model atmospheres and evolutionary isochrones.
    [Show full text]
  • Astro2020 Science White Paper Cool, Evolved Stars: Results, Challenges, and Promises for the Next Decade
    Astro2020 Science White Paper Cool, evolved stars: results, challenges, and promises for the next decade Thematic Areas: Planetary Systems Star and Planet Formation Formation and Evolution of Compact Objects Cosmology and Fundamental Physics 3Stars and Stellar Evolution Resolved Stellar Populations and their Environments Galaxy Evolution Multi-Messenger Astronomy and Astrophysics Principal Author: Name: Gioia Rau Institution: NASA/GSFC & CUA Email: [email protected] Phone: +1 (301) 286-6322 Co-authors: Rodolfo Montez Jr. (Center for Astrophysics (CfA) j Harvard & Smithsonian), Kenneth Carpenter (NASA/GSFC), Markus Wittkowski (ESO/Garching), Sara Bladh (Uppsala University), Margarita Karovska (CfA/Harvard & Smithsonian), Vladimir Airapetian (NASA/GFSC), Tom Ayres (University of Colorado), Martha Boyer (STScI), Andrea Chiavassa (OCA/Nice), Geoffrey Clayton (Louisiana State University), William Danchi (NASA/GSFC), Orsola De Marco (Macquarie University), Andrea K. Dupree (CfA/Harvard & Smithsonian), Tomasz Kaminski (CfA/Harvard & Smithsonian), Joel H. Kastner (RIT), Franz Kerschbaum (University of Vienna), Jeffrey Linsky (University of Colorado), Bruno Lopez (OCA/Nice), John Monnier (University of Michigan), Miguel Montarges` (KU Leuven), Krister Nielsen (CUA), Keiichi Ohnaka (Universidad Catolica del Norte Chile), Sofia Ramstedt (Uppsala University), Rachael Roettenbacher (Yale University), Theo ten Brummelaar (CHARA/GSU), Claudia Paladini (ESO/Chile), Arkaprabha Sarangi (NASA/GSFC & CRESST II-CUA), Gerard van Belle (Lowell Observatory), Paolo Ventura (INAF/OAR). Abstract: Cool, evolved stars are the main source of chemical enrichment of the interstellar medium (ISM), and understanding their mass loss and structure offers a unique opportunity to study the cycle of matter in the Universe. Pulsation, convection, and other dynamic processes in cool evolved stars create an atmosphere where molecules and dust can form, including those necessary to the formation of life (e.g.
    [Show full text]
  • Arxiv:1807.11559V1 [Astro-Ph.IM] 30 Jul 2018 2 Monnier, Kraus, Ireland, Et Al
    Experimental Astronomy manuscript No. (will be inserted by the editor) The Planet Formation Imager John D. Monnier, Stefan Kraus, Michael J. Ireland, Fabien Baron, Amelia Bayo, Jean-Philippe Berger, Michelle Creech-Eakman, Ruobing Dong, Gaspard Duchene, Catherine Espaillat, Chris Haniff, Sebastian H¨onig,Andrea Isella, Attila Juhasz, Lucas Labadie, Sylvestre Lacour, Stephanie Leifer, Antoine Merand, Ernest Michael, Stefano Minardi, Christoph Mordasini, David Mozurkewich, Johan Olofsson, Claudia Paladini, Romain Petrov, J¨org-Uwe Pott, Stephen Ridgway, Stephen Rinehart, Keivan Stassun, Jean Surdej, Theo ten Brummelaar, Neal Turner, Peter Tuthill, Kerry Vahala, Gerard van Belle, Gautam Vasisht, Ed Wishnow, John Young, Zhaohuan Zhu Received: date / Accepted: date Abstract The Planet Formation Imager (PFI, www.planetformationimager.org) is a next-generation infrared interferometer array with the primary goal of imaging the active phases of planet formation in nearby star forming regions. PFI will be sensitive to warm dust emission using mid-infrared capabilities made possible by precise fringe tracking in the near-infrared. An L/M band combiner will be especially sensitive to thermal emission from young exo- planets (and their disks) with a high spectral resolution mode to probe the kinematics of CO and H2O gas. In this paper, we give an overview of the main science goals of PFI, define a baseline PFI architecture that can achieve those goals, point at remaining technical challenges, and suggest activities today that will help make the Planet Formation Imager facility a reality. Keywords interferometry · infrared · planet formation · exoplanets John D. Monnier 1085 S. University Ave 311 West Hall Ann Arbor, MI 48109 USA Tel.: +1-734-763-5822 E-mail: [email protected] arXiv:1807.11559v1 [astro-ph.IM] 30 Jul 2018 2 Monnier, Kraus, Ireland, et al 1 Introduction Planet formation is one of the most exciting areas of modern astronomy.
    [Show full text]