Cfa in the News ~ Week Ending 3 January 2010
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Commission 27 of the Iau Information Bulletin
COMMISSION 27 OF THE I.A.U. INFORMATION BULLETIN ON VARIABLE STARS Nos. 2401 - 2500 1983 September - 1984 March EDITORS: B. SZEIDL AND L. SZABADOS, KONKOLY OBSERVATORY 1525 BUDAPEST, Box 67, HUNGARY HU ISSN 0374-0676 CONTENTS 2401 A POSSIBLE CATACLYSMIC VARIABLE IN CANCER Masaaki Huruhata 20 September 1983 2402 A NEW RR-TYPE VARIABLE IN LEO Masaaki Huruhata 20 September 1983 2403 ON THE DELTA SCUTI STAR BD +43d1894 A. Yamasaki, A. Okazaki, M. Kitamura 23 September 1983 2404 IQ Vel: IMPROVED LIGHT-CURVE PARAMETERS L. Kohoutek 26 September 1983 2405 FLARE ACTIVITY OF EPSILON AURIGAE? I.-S. Nha, S.J. Lee 28 September 1983 2406 PHOTOELECTRIC OBSERVATIONS OF 20 CVn Y.W. Chun, Y.S. Lee, I.-S. Nha 30 September 1983 2407 MINIMUM TIMES OF THE ECLIPSING VARIABLES AH Cep AND IU Aur Pavel Mayer, J. Tremko 4 October 1983 2408 PHOTOELECTRIC OBSERVATIONS OF THE FLARE STAR EV Lac IN 1980 G. Asteriadis, S. Avgoloupis, L.N. Mavridis, P. Varvoglis 6 October 1983 2409 HD 37824: A NEW VARIABLE STAR Douglas S. Hall, G.W. Henry, H. Louth, T.R. Renner 10 October 1983 2410 ON THE PERIOD OF BW VULPECULAE E. Szuszkiewicz, S. Ratajczyk 12 October 1983 2411 THE UNIQUE DOUBLE-MODE CEPHEID CO Aur E. Antonello, L. Mantegazza 14 October 1983 2412 FLARE STARS IN TAURUS A.S. Hojaev 14 October 1983 2413 BVRI PHOTOMETRY OF THE ECLIPSING BINARY QX Cas Thomas J. Moffett, T.G. Barnes, III 17 October 1983 2414 THE ABSOLUTE MAGNITUDE OF AZ CANCRI William P. Bidelman, D. Hoffleit 17 October 1983 2415 NEW DATA ABOUT THE APSIDAL MOTION IN THE SYSTEM OF RU MONOCEROTIS D.Ya. -
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. -
Planetary Phase Variations of the 55 Cancri System
The Astrophysical Journal, 740:61 (7pp), 2011 October 20 doi:10.1088/0004-637X/740/2/61 C 2011. The American Astronomical Society. All rights reserved. Printed in the U.S.A. PLANETARY PHASE VARIATIONS OF THE 55 CANCRI SYSTEM Stephen R. Kane1, Dawn M. Gelino1, David R. Ciardi1, Diana Dragomir1,2, and Kaspar von Braun1 1 NASA Exoplanet Science Institute, Caltech, MS 100-22, 770 South Wilson Avenue, Pasadena, CA 91125, USA; [email protected] 2 Department of Physics & Astronomy, University of British Columbia, Vancouver, BC V6T1Z1, Canada Received 2011 May 6; accepted 2011 July 21; published 2011 September 29 ABSTRACT Characterization of the composition, surface properties, and atmospheric conditions of exoplanets is a rapidly progressing field as the data to study such aspects become more accessible. Bright targets, such as the multi-planet 55 Cancri system, allow an opportunity to achieve high signal-to-noise for the detection of photometric phase variations to constrain the planetary albedos. The recent discovery that innermost planet, 55 Cancri e, transits the host star introduces new prospects for studying this system. Here we calculate photometric phase curves at optical wavelengths for the system with varying assumptions for the surface and atmospheric properties of 55 Cancri e. We show that the large differences in geometric albedo allows one to distinguish between various surface models, that the scattering phase function cannot be constrained with foreseeable data, and that planet b will contribute significantly to the phase variation, depending upon the surface of planet e. We discuss detection limits and how these models may be used with future instrumentation to further characterize these planets and distinguish between various assumptions regarding surface conditions. -
L RES~ARCH Coljncll ·
NA~IOf\i'At ACADEMIES OF SCIENCE AND ENGiNEERING 7 ·.· ·.·. : NATIONAL RES~ARCH ColJNCll · of the UNITED STATES OF AMERICA UNITED• STATES NATIONAL COMMITTEEI . International Union of Radio Sden<:e Nationa.1 Radio Science Meeting 13-15 January 1982 · f l··.. ·· Sponsored by USNC/URSI in cooperation with r Institute of Electrical and Electronics Engineers University of· Colorado Boulder, Colorado U.S.A. ~· 1' National Radio Science Meeting 13-15 January 19 82 Condensed Technical Program TUESDAY, 12 JANUARY 0900 CCIR U.S. Study Group 5 OT 8-8 CCIR U.S. Study ,Gr.oup 6 Radio Building 2000-2400 USNC/URSI Meeting Broker Inn WEDNESDAY, 13 JANUARY 0900-1200 A-1 Time Domai~ 1-ieasurements CRl-42 B-1 Scattering CR2-28 B-2 Electromagnetic Theory CR2-28 C-1 Topics in Information Theory CR0-30 F-1 Propagation Theory and Models CR2-26 J-1 Millimeter-Wave Astronomy UMC Ballroom 1330-1700 A-2 Microwave/Millimeter Wave Measurements CRl-42 B-3 Antenna Theory and Practice CR2-28 B-4 Inverse Scattering CR2-6 C-2 Digital HF: Equaltz ation and Reiated CR0-30 Techniques E-1 EM Noise in the Sea CRl-40 F-2 Ground-Based Remote Sensing CR2-26 H-1 VLF-ELF Wave Injection Into the CRl-46 Magnetosphere J-2 Very Long Baseline Interferometry UMC 157 1700 Commission A Business Meeting CRl-42 Commission C Business Meeting CR0-30 Commission E Business Meeting CRl-40 Commission F Business Meeting CR2-26 Commission H Business Meeting CRl-46 1800-2000 Reception Engineering Center 2000-2200 IEEE Wave Propagation Standards Committee CRl-46 TH.URSDAY, 14 JANUARY 0830-1200 A-3 -
Interior Dynamics of Super-Earth 55 Cancri E Constrained by General Circulation Models
Geophysical Research Abstracts Vol. 21, EGU2019-4167, 2019 EGU General Assembly 2019 © Author(s) 2019. CC Attribution 4.0 license. Interior dynamics of super-Earth 55 Cancri e constrained by general circulation models Tobias Meier (1), Dan J. Bower (1), Tim Lichtenberg (2), and Mark Hammond (2) (1) Center for Space and Habitability, Universität Bern , Bern, Switzerland , (2) Department of Physics, University of Oxford, Oxford, United Kingdom Close-in and tidally-locked super-Earths feature a day-side that always faces the host star and are thus subject to intense insolation. The thermal phase curve of 55 Cancri e, one of the best studied super-Earths, reveals a hotspot shift (offset of the maximum temperature from the substellar point) and a large day-night temperature contrast. Recent general circulation models (GCMs) aiming to explain these observations determine the spatial variability of the surface temperature of 55 Cnc e for different atmospheric masses and compositions. Here, we use constraints from the GCMs to infer the planet’s interior dynamics using a numerical geodynamic model of mantle flow. The geodynamic model is devised to be relatively simple due to uncertainties in the interior composition and structure of 55 Cnc e (and super-Earths in general), which preclude a detailed treatment of thermophysical parameters or rheology. We focus on several end-member models inspired by the GCM results to map the variety of interior regimes relevant to understand the present-state and evolution of 55 Cnc e. In particular, we investigate differences in heat transport and convective style between the day- and night-sides, and find that the thermal structure close to the surface and core-mantle boundary exhibits the largest deviations. -
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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). -
A Concise Dictionary of Middle English
A Concise Dictionary of Middle English A. L. Mayhew and Walter W. Skeat A Concise Dictionary of Middle English Table of Contents A Concise Dictionary of Middle English...........................................................................................................1 A. L. Mayhew and Walter W. Skeat........................................................................................................1 PREFACE................................................................................................................................................3 NOTE ON THE PHONOLOGY OF MIDDLE−ENGLISH...................................................................5 ABBREVIATIONS (LANGUAGES),..................................................................................................11 A CONCISE DICTIONARY OF MIDDLE−ENGLISH....................................................................................12 A.............................................................................................................................................................12 B.............................................................................................................................................................48 C.............................................................................................................................................................82 D...........................................................................................................................................................122 -
Arxiv:0809.1275V2
How eccentric orbital solutions can hide planetary systems in 2:1 resonant orbits Guillem Anglada-Escud´e1, Mercedes L´opez-Morales1,2, John E. Chambers1 [email protected], [email protected], [email protected] ABSTRACT The Doppler technique measures the reflex radial motion of a star induced by the presence of companions and is the most successful method to detect ex- oplanets. If several planets are present, their signals will appear combined in the radial motion of the star, leading to potential misinterpretations of the data. Specifically, two planets in 2:1 resonant orbits can mimic the signal of a sin- gle planet in an eccentric orbit. We quantify the implications of this statistical degeneracy for a representative sample of the reported single exoplanets with available datasets, finding that 1) around 35% percent of the published eccentric one-planet solutions are statistically indistinguishible from planetary systems in 2:1 orbital resonance, 2) another 40% cannot be statistically distinguished from a circular orbital solution and 3) planets with masses comparable to Earth could be hidden in known orbital solutions of eccentric super-Earths and Neptune mass planets. Subject headings: Exoplanets – Orbital dynamics – Planet detection – Doppler method arXiv:0809.1275v2 [astro-ph] 25 Nov 2009 Introduction Most of the +300 exoplanets found to date have been discovered using the Doppler tech- nique, which measures the reflex motion of the host star induced by the planets (Mayor & Queloz 1995; Marcy & Butler 1996). The diverse characteristics of these exoplanets are somewhat surprising. Many of them are similar in mass to Jupiter, but orbit much closer to their 1Carnegie Institution of Washington, Department of Terrestrial Magnetism, 5241 Broad Branch Rd. -
The Rings and Inner Moons of Uranus and Neptune: Recent Advances and Open Questions
Workshop on the Study of the Ice Giant Planets (2014) 2031.pdf THE RINGS AND INNER MOONS OF URANUS AND NEPTUNE: RECENT ADVANCES AND OPEN QUESTIONS. Mark R. Showalter1, 1SETI Institute (189 Bernardo Avenue, Mountain View, CA 94043, mshowal- [email protected]! ). The legacy of the Voyager mission still dominates patterns or “modes” seem to require ongoing perturba- our knowledge of the Uranus and Neptune ring-moon tions. It has long been hypothesized that numerous systems. That legacy includes the first clear images of small, unseen ring-moons are responsible, just as the nine narrow, dense Uranian rings and of the ring- Ophelia and Cordelia “shepherd” ring ε. However, arcs of Neptune. Voyager’s cameras also first revealed none of the missing moons were seen by Voyager, sug- eleven small, inner moons at Uranus and six at Nep- gesting that they must be quite small. Furthermore, the tune. The interplay between these rings and moons absence of moons in most of the gaps of Saturn’s rings, continues to raise fundamental dynamical questions; after a decade-long search by Cassini’s cameras, sug- each moon and each ring contributes a piece of the gests that confinement mechanisms other than shep- story of how these systems formed and evolved. herding might be viable. However, the details of these Nevertheless, Earth-based observations have pro- processes are unknown. vided and continue to provide invaluable new insights The outermost µ ring of Uranus shares its orbit into the behavior of these systems. Our most detailed with the tiny moon Mab. Keck and Hubble images knowledge of the rings’ geometry has come from spanning the visual and near-infrared reveal that this Earth-based stellar occultations; one fortuitous stellar ring is distinctly blue, unlike any other ring in the solar alignment revealed the moon Larissa well before Voy- system except one—Saturn’s E ring. -
10. Scientific Programme 10.1
10. SCIENTIFIC PROGRAMME 10.1. OVERVIEW (a) Invited Discourses Plenary Hall B 18:00-19:30 ID1 “The Zoo of Galaxies” Karen Masters, University of Portsmouth, UK Monday, 20 August ID2 “Supernovae, the Accelerating Cosmos, and Dark Energy” Brian Schmidt, ANU, Australia Wednesday, 22 August ID3 “The Herschel View of Star Formation” Philippe André, CEA Saclay, France Wednesday, 29 August ID4 “Past, Present and Future of Chinese Astronomy” Cheng Fang, Nanjing University, China Nanjing Thursday, 30 August (b) Plenary Symposium Review Talks Plenary Hall B (B) 8:30-10:00 Or Rooms 309A+B (3) IAUS 288 Astrophysics from Antarctica John Storey (3) Mon. 20 IAUS 289 The Cosmic Distance Scale: Past, Present and Future Wendy Freedman (3) Mon. 27 IAUS 290 Probing General Relativity using Accreting Black Holes Andy Fabian (B) Wed. 22 IAUS 291 Pulsars are Cool – seriously Scott Ransom (3) Thu. 23 Magnetars: neutron stars with magnetic storms Nanda Rea (3) Thu. 23 Probing Gravitation with Pulsars Michael Kremer (3) Thu. 23 IAUS 292 From Gas to Stars over Cosmic Time Mordacai-Mark Mac Low (B) Tue. 21 IAUS 293 The Kepler Mission: NASA’s ExoEarth Census Natalie Batalha (3) Tue. 28 IAUS 294 The Origin and Evolution of Cosmic Magnetism Bryan Gaensler (B) Wed. 29 IAUS 295 Black Holes in Galaxies John Kormendy (B) Thu. 30 (c) Symposia - Week 1 IAUS 288 Astrophysics from Antartica IAUS 290 Accretion on all scales IAUS 291 Neutron Stars and Pulsars IAUS 292 Molecular gas, Dust, and Star Formation in Galaxies (d) Symposia –Week 2 IAUS 289 Advancing the Physics of Cosmic -
The Third Catalog of Active Galactic Nuclei Detected by the Fermi Large Area Telescope M
The Astrophysical Journal, 810:14 (34pp), 2015 September 1 doi:10.1088/0004-637X/810/1/14 © 2015. The American Astronomical Society. All rights reserved. THE THIRD CATALOG OF ACTIVE GALACTIC NUCLEI DETECTED BY THE FERMI LARGE AREA TELESCOPE M. Ackermann1, M. Ajello2, W. B. Atwood3, L. Baldini4, J. Ballet5, G. Barbiellini6,7, D. Bastieri8,9, J. Becerra Gonzalez10,11, R. Bellazzini12, E. Bissaldi13, R. D. Blandford14, E. D. Bloom14, R. Bonino15,16, E. Bottacini14, T. J. Brandt10, J. Bregeon17, R. J. Britto18, P. Bruel19, R. Buehler1, S. Buson8,9, G. A. Caliandro14,20, R. A. Cameron14, M. Caragiulo13, P. A. Caraveo21, B. Carpenter10,22, J. M. Casandjian5, E. Cavazzuti23, C. Cecchi24,25, E. Charles14, A. Chekhtman26, C. C. Cheung27, J. Chiang14, G. Chiaro9, S. Ciprini23,24,28, R. Claus14, J. Cohen-Tanugi17, L. R. Cominsky29, J. Conrad30,31,32,70, S. Cutini23,24,28,R.D’Abrusco33,F.D’Ammando34,35, A. de Angelis36, R. Desiante6,37, S. W. Digel14, L. Di Venere38, P. S. Drell14, C. Favuzzi13,38, S. J. Fegan19, E. C. Ferrara10, J. Finke27, W. B. Focke14, A. Franckowiak14, L. Fuhrmann39, Y. Fukazawa40, A. K. Furniss14, P. Fusco13,38, F. Gargano13, D. Gasparrini23,24,28, N. Giglietto13,38, P. Giommi23, F. Giordano13,38, M. Giroletti34, T. Glanzman14, G. Godfrey14, I. A. Grenier5, J. E. Grove27, S. Guiriec10,2,71, J. W. Hewitt41,42, A. B. Hill14,43,68, D. Horan19, R. Itoh40, G. Jóhannesson44, A. S. Johnson14, W. N. Johnson27, J. Kataoka45,T.Kawano40, F. Krauss46, M. Kuss12, G. La Mura9,47, S. Larsson30,31,48, L. -
The B3-VLA CSS Sample⋆
A&A 528, A110 (2011) Astronomy DOI: 10.1051/0004-6361/201015379 & c ESO 2011 Astrophysics The B3-VLA CSS sample VIII. New optical identifications from the Sloan Digital Sky Survey The ultraviolet-optical spectral energy distribution of the young radio sources C. Fanti1,R.Fanti1, A. Zanichelli1, D. Dallacasa1,2, and C. Stanghellini1 1 Istituto di Radioastronomia – INAF, via Gobetti 101, 40129 Bologna, Italy e-mail: [email protected] 2 Dipartimento di Astronomia, Università di Bologna, via Ranzani 1, 40127 Bologna, Italy Received 12 July 2010 / Accepted 22 December 2010 ABSTRACT Context. Compact steep-spectrum radio sources and giga-hertz peaked spectrum radio sources (CSS/GPS) are generally considered to be mostly young radio sources. In recent years we studied at many wavelengths a sample of these objects selected from the B3-VLA catalog: the B3-VLA CSS sample. Only ≈60% of the sources were optically identified. Aims. We aim to increase the number of optical identifications and study the properties of the host galaxies of young radio sources. Methods. We cross-correlated the CSS B3-VLA sample with the Sloan Digital Sky Survey (SDSS), DR7, and complemented the SDSS photometry with available GALEX (DR 4/5 and 6) and near-IR data from UKIRT and 2MASS. Results. We obtained new identifications and photometric redshifts for eight faint galaxies and for one quasar and two quasar candi- dates. Overall we have 27 galaxies with SDSS photometry in five bands, for which we derived the ultraviolet-optical spectral energy distribution (UV-O-SED). We extended our investigation to additional CSS/GPS selected from the literature.