DOCSLIB.ORG

Dynamite Diameters

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Dynamite Diameters CHARA Collaboration Year-Five Science Review Dynamite Diameters Tabetha Boyajian GSU/CHARA Presented by Hal McAlister CHARA Collaboration Year-Five Science Review Goals • To measure the angular diameter (θ) of a large sample of A, F, and G main sequence stars with the CHARA Array to better than 4% accuracy – Establish effective temperatures to better than 2% – Absolute luminosity HR diagram – Test stellar evolution models • Metallicity and age • Duplicity – Rotation effects CHARA Collaboration Year-Five Science Review Target Selection • HIPPARCOS Catalogue Query – Spectral type: defined by B‐V colors – Distance limit: Estimated radii from spectral types gives maximum distance (i.e. angular size) for each spectral type. • The error on diameter is directly related to how far down the visibility curve that you can sample. For 4% accuracy, limits are θ >0.65 mas in K‐band and θ>0.50 mas in H band – Folding in CHARA declination and magnitude observing limits and and filtering out the abnormal stars, there are ~90 stars, all with θ<1.7 mas, 25 with θ>1.0 mas CHARA Collaboration Year-Five Science Review Observing Dynamite Diameters • 50 stars observed over the past 2 years – 20 G stars, 22 F stars and 8 A stars • Observed on more than one – Date – Baseline – Calibrator to obtain highly reliable (and precise) angular diameters for the program stars • H‐band data acquisition not successful CHARA Collaboration Year-Five Science Review Examples CHARA Collaboration Year-Five Science Review Examples CHARA Collaboration Year-Five Science Review Empirical HR Diagram • Linear radii – The measured angular diameter combined with the parallax gives the linear radius of the star • Effective temperatures – The measured angular diameter combined with the bolometric flux gives the effective temperature of the star CHARA Collaboration Year-Five Science Review Fundamentally determined plot from the observations to‐date. The size of circle represents the linear size of the star. The 1‐σ errors are indicated. HD 122563 HD 95418 (A1V) HD 177724 (A0Vn) HD 48737 HD 81937 (F5IV) (F0IV) HD 195564 HD 58946 (G6 IV) (F0V) Sun (G2V) HD 103095 (G8Vp) μ Cas A 61 Cyg A + B (G5Vp); (K5V + K7V) σ Dra (K0V) A0 F0 G0 K0 K7 CHARA Collaboration Year-Five Science Review AnAnAn InterferometricInterferometricInterferometric HRHRHR DiagramDiagramDiagram ComplimentsCompliments of of Tabetha Tabetha Boyajian Boyajian CHARA Collaboration Year-Five Science Review RedRedRed GiantsGiantsGiants ininin thethethe HyadesHyadesHyades KnownKnown Cluster Cluster Age Age is is an an Asset Asset in in Modeling Modeling CHARA Collaboration Year-Five Science Review RedRedRed GiantsGiantsGiants ininin thethethe HyadesHyadesHyades BoyajianBoyajian et et al. al. ApJ ApJ 2009. 2009. 625 Myr (Padova) isochrones with slightly varying heavy element abundances for existing and new results for Hyades giants. CHARA values show the stars sitting pretty on the Red Giant Clump. CHARA Collaboration Year-Five Science Review FirstFirstFirst DiameterDiameterDiameter forforfor aaa PopulationPopulationPopulation IIIIII StarStarStar Cas A CHARA Collaboration Year-Five Science Review DiameterDiameter ofof LowLow-Metallicity-Metallicity StarStar µµ CasCas AA BoyajianBoyajian et et al. al. ApJ ApJ 2008. 2008. For µ Cas A: LD = 0.973 ± 0.009 mas Figure shows radii for EBs and LBOI targets for G to mid-K along with ZAMS for 3 target stars and the evolutionary track for µ Cas A. Models (Y2 and V-R) for such metal-poor stars obviously need improvement..
Load more

Recommended publications
  • Download This Article in PDF Format
    A&A 646, A77 (2021) Astronomy https://doi.org/10.1051/0004-6361/202039765 & c ESO 2021 Astrophysics Stellar chromospheric activity of 1674 FGK stars from the AMBRE-HARPS sample I. A catalogue of homogeneous chromospheric activity? J. Gomes da Silva1, N. C. Santos1,2, V. Adibekyan1,2, S. G. Sousa1, T. L. Campante1,2, P. Figueira3,1, D. Bossini1, E. Delgado-Mena1, M. J. P. F. G. Monteiro1,2, P. de Laverny4, A. Recio-Blanco4, and C. Lovis5 1 Instituto de Astrofísica e Ciências do Espaço, Universidade do Porto, CAUP, Rua das Estrelas, 4150-762 Porto, Portugal e-mail: [email protected] 2 Departamento de Fiísica e Astronomia, Faculdade de Ciências, Universidade do Porto, 4169-007 Porto, Portugal 3 European Southern Observatory, Alonso de Cordova 3107, Vitacura, Santiago, Chile 4 Université Côte d’Azur, Observatoire de la Côte d’Azur, CNRS, Laboratoire Lagrange, Nice, France 5 Observatoire Astronomique de l’Université de Genève, 51 Ch. des Maillettes, 1290 Versoix, Switzerland Received 26 October 2020 / Accepted 15 December 2020 ABSTRACT Aims. The main objective of this project is to characterise chromospheric activity of FGK stars from the HARPS archive. We start, in this first paper, by presenting a catalogue of homogeneously determined chromospheric emission (CE), stellar atmospheric parameters, and ages for 1674 FGK main sequence (MS), subgiant, and giant stars. The analysis of CE level and variability is also performed. Methods. We measured CE in the Ca ii H&K lines using more than 180 000 high-resolution spectra from the HARPS spectrograph, as compiled in the AMBRE project, obtained between 2003 and 2019.
    [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]
  • Do We Know of Any Maunder Minimum Stars?1
    Do We Know of any Maunder Minimum Stars?1 J. T. Wright Department of Astronomy, University of California at Berkeley, 601 Campbell Hall, Berkeley, CA 94720-3411 [email protected] Received ; accepted 1Based on observations obtained at the W. M. Keck Observatory, which is operated jointly by the University of California and the California Institute of Technology. The Keck Observatory was made possible by the generous financial support of the W.M. Keck Foundation. –2– ABSTRACT Most stars previously identified as Maunder minimum stars are old stars evolved off of the main sequence. Analysis of activity measurements from the California and Carnegie Planet Search program stars and Hipparcos parallaxes implies that the canonical age-chromospheric activity relation breaks down for stars older than ∼ 6 Gyr when activity is calculated from Mount Wilson S values. Stars only 1 magnitude above the main sequence exhibit significantly suppressed activity levels which have been mistaken for examples of Maunder minimum behavior. Subject headings: Sun: activity, stars: activity, chromospheres, evolution –3– 1. Introduction Studies of the star formation history of the galaxy, searches for extrasolar planets, and studies of the Sun as a star often benefit from the ability to determine the age of sun-like stars. But, because stars change very little during their lifetime on the main sequence, determining their age is difficult. An important tool for making that determination is the simple, monotonic relation between age and chromospheric activity. As stars age, they lose angular momentum and have less magnetic activity on their surfaces. Magnetic fields lead to chromospheric heating, which is balanced by cooling in, among others, the Ca II H&K lines.
    [Show full text]
  • Publications of the Astronomical Society of the Pacific 106: 382-396, 1994 April
    Publications of the Astronomical Society of the Pacific 106: 382-396, 1994 April An Atlas of Southern MK Standards From 5800 to 10,200 A1 Anthony C. Danks Hughes STX/Goddard Space Flight Center, Code 683.0, Greenbelt, Maryland 20771 Michel Dennefeld Institut d'Astrophysique, 98bis Boulevard Arago, F-75014 Paris, France Received 1992 December 30; accepted 1994 February 2 ABSTRACT. An atlas of stellar spectra covering the wavelength range from 5800 to 10,200 A is presented of 126 southern MK standard stars, covering the luminosity classes I, III, and V. Some peculiar stars are included for comparison purposes. The spectra were obtained at a resolution of 4.3 A per pixel using a Cassegrain-mounted Boiler and Chivens spectrograph equipped with a Reticon detector. The quality and utility of the data are discussed and examples of the spectra are presented. The atlas is available in digital format through the NSSDC. 1. INTRODUCTION tion of 15 A which is lower than that used in this atlas, but overlaps nicely in wavelength. Mantegazza (1992) has be- Spectral synthesis of galaxies is one of the major driving forces for producing new stellar libraries covering as large gun the work of extending calibration to the Magellanic a spectral interval as possible. The "photographic" wave- clouds by observing 34 LMC and 15 SMC supergiants be- length region from 3800 to 4800 A, initially used for the tween AO and G5 in the wavelength range from 5600 to MK classification scheme, has been extended to shorter 9000 A, interestingly made with the same spectrograph as wavelengths through space technology.
    [Show full text]
  • Extrasolar Planets and Their Host Stars
    Kaspar von Braun & Tabetha S. Boyajian Extrasolar Planets and Their Host Stars July 25, 2017 arXiv:1707.07405v1 [astro-ph.EP] 24 Jul 2017 Springer Preface In astronomy or indeed any collaborative environment, it pays to figure out with whom one can work well. From existing projects or simply conversations, research ideas appear, are developed, take shape, sometimes take a detour into some un- expected directions, often need to be refocused, are sometimes divided up and/or distributed among collaborators, and are (hopefully) published. After a number of these cycles repeat, something bigger may be born, all of which one then tries to simultaneously fit into one’s head for what feels like a challenging amount of time. That was certainly the case a long time ago when writing a PhD dissertation. Since then, there have been postdoctoral fellowships and appointments, permanent and adjunct positions, and former, current, and future collaborators. And yet, con- versations spawn research ideas, which take many different turns and may divide up into a multitude of approaches or related or perhaps unrelated subjects. Again, one had better figure out with whom one likes to work. And again, in the process of writing this Brief, one needs create something bigger by focusing the relevant pieces of work into one (hopefully) coherent manuscript. It is an honor, a privi- lege, an amazing experience, and simply a lot of fun to be and have been working with all the people who have had an influence on our work and thereby on this book. To quote the late and great Jim Croce: ”If you dig it, do it.
    [Show full text]
  • Arxiv:1306.2974V1
    Draft version June 14, 2013 Preprint typeset using LATEX style emulateapj v. 03/07/07 STELLAR DIAMETERS AND TEMPERATURES III. MAIN SEQUENCE A, F, G, & K STARS: ADDITIONAL HIGH-PRECISION MEASUREMENTS AND EMPIRICAL RELATIONS Tabetha S. Boyajian1,2, Kaspar von Braun3,4, Gerard van Belle5, Chris Farrington6, Gail Schaefer6, Jeremy Jones1, Russel White1, Harold A. McAlister1, Theo A. ten Brummelaar6, Stephen Ridgway7, Douglas Gies1, Laszlo Sturmann6, Judit Sturmann6, Nils H. Turner6, P. J. Goldfinger6, Norm Vargas6 Draft version June 14, 2013 ABSTRACT Based on CHARA Array measurements, we present the angular diameters of 23 nearby, main- sequence stars, ranging from spectral type A7 to K0, five of which are exoplanet host stars. We derive linear radii, effective temperatures, and absolute luminosities of the stars using HIPPARCOS parallaxes and measured bolometric fluxes. The new data are combined with previously published values to create an Angular Diameter Anthology of measured angular diameters to main-sequence stars (luminosity class V and IV). This compilation consists of 125 stars with diameter uncertainties of less than 5%, ranging in spectral types from A to M. The large quantity of empirical data are used to derive color-temperature relations to an assortment of color indices in the Johnson (BV RJIJJHK), Cousins (RCIC), Kron (RKIK), Sloan (griz), and WISE (W3W4) photometric systems. These relations have an average standard deviation of ∼ 3% and are valid for stars with spectral types A0 to M4. To derive even more accurate relations for Sun-like stars, we also determined these temperature relations omitting early-type stars (Teff > 6750 K) that may have biased luminosity estimates because of rapid rotation; for this subset the dispersion is only ∼ 2.5%.
    [Show full text]
  • Arxiv:1207.6212V2 [Astro-Ph.GA] 1 Aug 2012
    Draft: Submitted to ApJ Supp. A Preprint typeset using LTEX style emulateapj v. 5/2/11 PRECISE RADIAL VELOCITIES OF 2046 NEARBY FGKM STARS AND 131 STANDARDS1 Carly Chubak2, Geoffrey W. Marcy2, Debra A. Fischer5, Andrew W. Howard2,3, Howard Isaacson2, John Asher Johnson4, Jason T. Wright6,7 (Received; Accepted) Draft: Submitted to ApJ Supp. ABSTRACT We present radial velocities with an accuracy of 0.1 km s−1 for 2046 stars of spectral type F,G,K, and M, based on ∼29000 spectra taken with the Keck I telescope. We also present 131 FGKM standard stars, all of which exhibit constant radial velocity for at least 10 years, with an RMS less than 0.03 km s−1. All velocities are measured relative to the solar system barycenter. Spectra of the Sun and of asteroids pin the zero-point of our velocities, yielding a velocity accuracy of 0.01 km s−1for G2V stars. This velocity zero-point agrees within 0.01 km s−1 with the zero-points carefully determined by Nidever et al. (2002) and Latham et al. (2002). For reference we compute the differences in velocity zero-points between our velocities and standard stars of the IAU, the Harvard-Smithsonian Center for Astrophysics, and l’Observatoire de Geneve, finding agreement with all of them at the level of 0.1 km s−1. But our radial velocities (and those of all other groups) contain no corrections for convective blueshift or gravitational redshifts (except for G2V stars), leaving them vulnerable to systematic errors of ∼0.2 km s−1 for K dwarfs and ∼0.3 km s−1 for M dwarfs due to subphotospheric convection, for which we offer velocity corrections.
    [Show full text]
  • On the Mass Estimation for FGK Stars: Comparison of Several Methods
    Mon. Not. R. Astron. Soc. 000, 1–?? (2002) Printed 29 August 2014 (MN LATEX style file v2.2) On the mass estimation for FGK stars: comparison of several methods F. J. G. Pinheiro1,2⋆, J. M. Fernandes1,2,3, M. S. Cunha4,5, M. J. P. F. G. Monteiro4,5,6, N. C. Santos4,5,6, S. G. Sousa4,5,6, J. P. Marques7, J.-J. Fang8, A. Mortier9 and J. Sousa4,5 1Centro de Geofísica da Universidade de Coimbra 2Observatório Geofísico e Astronómico da Universidade de Coimbra 3Departamento de Matemática da Universidade de Coimbra, Largo D. Dinis, P-3001-454 Coimbra, Portugal 4Instituto de Astrofísica e Ciências do Espaço, Universidade do Porto, CAUP, Rua das Estrelas, PT4150-762 Porto, Portugal 5Centro de Astrofísica, Universidade do Porto, Rua das Estrelas, 4150-762 Porto, Portugal 6Departamento de Física e Astronomia, Faculdade de Ciências, Universidade do Porto, Portugal 7The Institut d’Astrophysique Spatiale, Orsay, France 8Centro de Física Computacional, Department of Physics, University of Coimbra, P-3004-516 Coimbra, Portugal 9SUPA, School of Physics and Astronomy, University of St Andrews, St Andrews KY16 9SS, UK Accepted . Received ABSTRACT Stellar evolutionary models simulate well binary stars when individual stellar mass and system metallicity are known. The mass can be derived directly from observations only in the case of multiple stellar systems, mainly binaries. Yet the number of such stars for which ls accurate stellar masses are available is rather small. The main goal of this project is to provide realistic mass estimates for an homogeneous sample of about a thousand FGK single stars, using four different methods and techniques.
    [Show full text]
  • Astrophysical Insights Into Radial Velocity Jitter from an Analysis of 600 Planet-Search Stars
    The Astronomical Journal, 159:235 (33pp), 2020 May https://doi.org/10.3847/1538-3881/ab855a © 2020. The American Astronomical Society. All rights reserved. Astrophysical Insights into Radial Velocity Jitter from an Analysis of 600 Planet-search Stars Jacob K. Luhn1,2,5 , Jason T. Wright1,2 , Andrew W. Howard3 , and Howard Isaacson4 1 Department of Astronomy, The Pennsylvania State University, 525 Davey Lab, University Park, PA 16802, USA; [email protected] 2 Center for Exoplanets and Habitable Worlds, 525 Davey Lab, The Pennsylvania State University, University Park, PA 16802, USA 3 Department of Astronomy, California Institute of Technology, Pasadena, CA, USA 4 Astronomy Department, University of California, Berkeley, CA, USA Received 2019 October 23; revised 2020 March 2; accepted 2020 March 3; published 2020 April 27 Abstract Radial velocity (RV) detection of planets is hampered by astrophysical processes on the surfaces of stars that induce a stochastic signal, or “jitter,” which can drown out or even mimic planetary signals. Here, we empirically and carefully measure the RV jitter of more than 600 stars from the California Planet Search sample on a star by star basis. As part of this process, we explore the activity–RV correlation of stellar cycles and include appendices listing every ostensibly companion-induced signal we removed and every activity cycle we noted. We then use precise stellar properties from Brewer et al. to separate the sample into bins of stellar mass and examine trends with activity and with evolutionary state. We find that RV jitter tracks stellar evolution and that in general, stars evolve through different stages of RV jitter: the jitter in younger stars is driven by magnetic activity, while the jitter in older stars is convectively driven and dominated by granulation and oscillations.
    [Show full text]
  • A Survey of Stellar Families: Multiplicity of Solar-Type Stars
    to appear in the Astrophysical Journal A Survey of Stellar Families: Multiplicity of Solar-Type Stars Deepak Raghavan1,2, Harold A. McAlister1, Todd J. Henry1, David W. Latham3, Geoffrey W. Marcy4, Brian D. Mason5, Douglas R. Gies1, Russel J. White1, Theo A. ten Brummelaar6 ABSTRACT We present the results of a comprehensive assessment of companions to solar- type stars. A sample of 454 stars, including the Sun, was selected from the Hipparcos catalog with π > 40 mas, σπ/π < 0.05, 0.5 ≤ B − V ≤ 1.0 (∼ F6– K3), and constrained by absolute magnitude and color to exclude evolved stars. These criteria are equivalent to selecting all dwarf and subdwarf stars within 25 pc with V -band flux between 0.1 and 10 times that of the Sun, giving us a physical basis for the term “solar-type”. New observational aspects of this work include surveys for (1) very close companions with long-baseline interferometry at the Center for High Angular Resolution Astronomy (CHARA) Array, (2) close companions with speckle interferometry, and (3) wide proper motion companions identified by blinking multi-epoch archival images. In addition, we include the re- sults from extensive radial-velocity monitoring programs and evaluate companion information from various catalogs covering many different techniques. The results presented here include four new common proper motion companions discovered by blinking archival images. Additionally, the spectroscopic data searched reveal five new stellar companions. Our synthesis of results from many methods and sources results in a thorough evaluation of stellar and brown dwarf companions to nearby Sun-like stars. 1Center for High Angular Resolution Astronomy, Georgia State University, P.O.
    [Show full text]
  • Cal. Legacy Survey I
    The Astrophysical Journal Supplement Series, 255:8 (67pp), 2021 July https://doi.org/10.3847/1538-4365/abe23c © 2021. The American Astronomical Society. All rights reserved. The California Legacy Survey. I. A Catalog of 178 Planets from Precision Radial Velocity Monitoring of 719 Nearby Stars over Three Decades Lee J. Rosenthal1 , Benjamin J. Fulton1,2 , Lea A. Hirsch3 , Howard T. Isaacson4 , Andrew W. Howard1 , Cayla M. Dedrick1,5 , Ilya A. Sherstyuk1, Sarah C. Blunt1,18 , Erik A. Petigura6 , Heather A. Knutson7 , Aida Behmard7,18 , Ashley Chontos8,18 , Justin R. Crepp9 , Ian J. M. Crossfield10, Paul A. Dalba11,19 , Debra A. Fischer12 , Gregory W. Henry13 , Stephen R. Kane11 , Molly Kosiarek14,18 , Geoffrey W. Marcy4 , Ryan A. Rubenzahl1,18 , Lauren M. Weiss8 , and Jason T. Wright15,16,17 1 Cahill Center for Astronomy & Astrophysics, California Institute of Technology, Pasadena, CA 91125, USA 2 IPAC-NASA Exoplanet Science Institute, Pasadena, CA 91125, USA 3 Kavli Institute for Particle Astrophysics and Cosmology, Stanford University, Stanford, CA 94305, USA 4 Department of Astronomy, University of California Berkeley, Berkeley, CA 94720, USA 5 Department of Astronomy & Astrophysics, The Pennsylvania State University, 525 Davey Lab, University Park, PA 16802, USA 6 Department of Physics & Astronomy, University of California Los Angeles, Los Angeles, CA 90095, USA 7 Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125, USA 8 Institute for Astronomy, University of Hawaii, Honolulu, HI 96822,
    [Show full text]