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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, -
Intervening Material in Sight-Lines Towards Grbs and Qsos
Programa de Doctorado en F´ısica y Matem´aticas Universidad de Granada Cosmic Lighthouses at High Redshift: Intervening material in sight-lines towards GRBs and QSOs Rub´en S´anchez Ram´ırez Thesis submitted for the degree of Doctor of Philosophy 10 June 2016 Supervisors: Prof. Javier Gorosabel Urkia, Dr. Antonio de Ugarte Postigo, and Prof. Alberto J. Castro Tirado Instituto de Astrof´ısica de Andaluc´ıa Consejo Superior de Investigaciones Cient´ıficas Para todos aquellos que caminaron a mi lado, a´unsin yo mismo entender hacia d´ondeme dirig´ıa... ii In Memoriam Javier Gorosabel Urquia (1969 - 2015) “El polvo de las estrellas se convirti´oun dia en germen de vida. Y de ´elsurgimos nosotros en algun momento. Y asi vivimos, creando y recreando nuestro ambito. Sin descanso. Trabajando pervivimos. Y a esa dura cadena estamos todos atados.” — Izarren Hautsa, Mikel Laboa “La vida son estos momentos que luego se te olvidan”. Esa fue la conclusi´on a la que lleg´oJavier al final de uno de esos fant´asticos d´ıas intensos y maratonianos a los que me ten´ıa acostumbrado. Vi´endolo ahora con perspectiva estaba en lo cierto, porque por m´as que me esfuerce en recordar y explicar lo que era el d´ıa a d´ıa con ´el, no puedo transmitir con justicia lo que realmente fue. La reconstrucci´on de esos momentos es inevitablemente incompleta. Contaros c´omo era Javier como jefe es muy sencillo: ´el nunca se comport´ocomo un jefe conmigo. Nunca orden´o. Siempre me dec´ıa, lleno de orgullo, que no le hac´ıa ni caso. -
1949 Celebrating 65 Years of Bringing Astronomy to North Texas 2014
1949 Celebrating 65 Years of Bringing Astronomy to North Texas 2014 Contact information: Inside this issue: Info Officer (General Info)– [email protected]@fortworthastro.com Website Administrator – [email protected] Postal Address: Page Fort Worth Astronomical Society July Club Calendar 3 3812 Fenton Avenue Fort Worth, TX 76133 Celestial Events 4 Web Site: http://www.fortworthastro.org Facebook: http://tinyurl.com/3eutb22 Sky Chart 5 Twitter: http://twitter.com/ftwastro Yahoo! eGroup (members only): http://tinyurl.com/7qu5vkn Moon Phase Calendar 6 Officers (2014-2015): Mecury/Venus Data Sheet 7 President – Bruce Cowles, [email protected] Vice President – Russ Boatwright, [email protected] Young Astronomer News 8 Sec/Tres – Michelle Theisen, [email protected] Board Members: Cloudy Night Library 9 2014-2016 The Astrolabe 10 Mike Langohr Tree Oppermann AL Obs Club of the Month 14 2013-2015 Bill Nichols Constellation of the Month 15 Jim Craft Constellation Mythology 19 Cover Photo This is an HaLRGB image of M8 & Prior Club Meeting Minutes 23 M20, composed entirely from a T3i General Club Information 24 stack of one shot color. Collected the data over a period of two nights. That’s A Fact 24 Taken by FWAS member Jerry Keith November’s Full Moon 24 Observing Site Reminders: Be careful with fire, mind all local burn bans! FWAS Foto Files 25 Dark Site Usage Requirements (ALL MEMBERS): Maintain Dark-Sky Etiquettehttp://tinyurl.com/75hjajy ( ) Turn out your headlights at the gate! Sign -
The Nasa-Uc Eta-Earth Program: Ii. a Planet
Submitted to ApJ A Preprint typeset using LTEX style emulateapj v. 04/20/08 THE NASA-UC ETA-EARTH PROGRAM: II. A PLANET ORBITING HD156668 WITH A MINIMUM MASS OF FOUR EARTH MASSES1 Andrew W. Howard2,3, John Asher Johnson4, Geoffrey W. Marcy2, Debra A. Fischer5, Jason T. Wright6, Gregory W. Henry7, Howard Isaacson2, Jeff A. Valenti8, Jay Anderson8, and Nikolai E. Piskunov9 Submitted to ApJ ABSTRACT We report the discovery of HD156668b, an extrasolar planet with a minimum mass of MP sin i = 4.15 M⊕. This planet was discovered through Keplerian modeling of precise radial ve- locities from Keck-HIRES and is the second super-Earth to emerge from the NASA-UC Eta-Earth Survey. The best-fit orbit is consistent with circular and has a period of P = 4.6455 d. The Doppler semi-amplitude of this planet, K = 1.89 m s−1, is among the lowest ever detected, on par with the detection of GJ581e using HARPS. A longer period (P ≈ 2.3 yr), low-amplitude signal of unknown origin was also detected in the radial velocities and was filtered out of the data while fitting the short-period planet. Additional data are required to determine if the long-period signal is due to a second planet, stellar activity, or another source. Photometric observations using the Automated Photometric Telescopes at Fairborn Observatory show that HD156668 (an old, quiet K3 dwarf) is photometrically constant over the radial velocity period to 0.1 mmag, supporting the existence of the planet. No transits were detected down to a photometric limit of ∼3 mmag, ruling out transiting planets dominated by extremely bloated atmospheres, but not precluding a transiting solid/liquid planet with a modest atmosphere. -
Evidence for Enhanced Chromospheric Ca II H and K Emission in Stars with Close-In Extrasolar Planets
A&A 540, A82 (2012) Astronomy DOI: 10.1051/0004-6361/201118247 & c ESO 2012 Astrophysics Evidence for enhanced chromospheric Ca II H and K emission in stars with close-in extrasolar planets T. Krejcovᡠ1 and J. Budaj2 1 Department of Theoretical Physics and Astrophysics, Masaryk University, Kotlárskᡠ2, 61137 Brno, Czech Republic e-mail: [email protected] 2 Astronomical Institute, Slovak Academy of Sciences, 05960 Tatranská Lomnica, Slovak Republic e-mail: [email protected] Received 11 October 2011 / Accepted 13 February 2012 ABSTRACT Context. The planet-star interaction is manifested in many ways. It has been found that a close-in exoplanet causes small but mea- surable variability in the cores of a few lines in the spectra of several stars, which corresponds to the orbital period of the exoplanet. Stars with and without exoplanets may have different properties. Aims. The main goal of our study is to search for the influence that exoplanets might have on atmospheres of their host stars. Unlike the previous studies, we do not study changes in the spectrum of a host star or differences between stars with and without exoplanets. We aim to study a large number of stars with exoplanets and the current level of their chromospheric activity and to look for a possible correlation with the exoplanetary properties. Methods. To analyse the chromospheric activity of stars, we exploited our own and publicly available archival spectra, measured the equivalent widths of the cores of Ca II H and K lines, and used them to trace their activity. Subsequently, we searched for their dependence on the orbital parameters and the mass of the exoplanet. -
July 2014 BRAS Newsletter
July, 2014 Next Meeting July 19th, 11:00AM at LIGO The LIGO facility in Livingston Parish, LA What's In This Issue? President's Message Secretary's Summary of June Meeting Astroshort- Not-So-Rare Earths Message from the HRPO Globe At Night EBR Parish Library Children's Reading Program Recent BRAS Forum Entries Observing Notes from John Nagle President's Message WE WILL NOT MEET ON THE SECOND MONDAY NIGHT, AS WE USUALLY DO. Our next meeting will be Saturday, July 19, 2014, 11 AM – 4 PM at LIGO, Livingston. It will be a picnic/star-b-cue and enjoy each other’s company. We will meet under the pavilion by the pond at 11 AM to begin the picnic. BRAS will provide the main course. You can bring a small dish if you wish. At 1 PM, we can join the public for LIGO’s regular Saturday Science day activities. That includes the museum, hands on experiments, a video about LIGO “Einstein’s Messengers”, and a tour of the facility. One new thing we would like to do is set a table aside for anyone who has astronomical equipment they want to sell – telescopes, mounts, accessories, binoculars, cameras, books, etc. The idea is to have an impromptu garage sale (or swap meet). Bring what you have and let’s see if we can move it. LIGO is only open during the day, so the only stargazing we will be able to do will be solar. However, we will demonstrate the 35mm Lundt solar scope BRAS is raffling and sell tickets for the raffle. -
Survival of Exomoons Around Exoplanets 2
Survival of exomoons around exoplanets V. Dobos1,2,3, S. Charnoz4,A.Pal´ 2, A. Roque-Bernard4 and Gy. M. Szabo´ 3,5 1 Kapteyn Astronomical Institute, University of Groningen, 9747 AD, Landleven 12, Groningen, The Netherlands 2 Konkoly Thege Mikl´os Astronomical Institute, Research Centre for Astronomy and Earth Sciences, E¨otv¨os Lor´and Research Network (ELKH), 1121, Konkoly Thege Mikl´os ´ut 15-17, Budapest, Hungary 3 MTA-ELTE Exoplanet Research Group, 9700, Szent Imre h. u. 112, Szombathely, Hungary 4 Universit´ede Paris, Institut de Physique du Globe de Paris, CNRS, F-75005 Paris, France 5 ELTE E¨otv¨os Lor´and University, Gothard Astrophysical Observatory, Szombathely, Szent Imre h. u. 112, Hungary E-mail: [email protected] January 2020 Abstract. Despite numerous attempts, no exomoon has firmly been confirmed to date. New missions like CHEOPS aim to characterize previously detected exoplanets, and potentially to discover exomoons. In order to optimize search strategies, we need to determine those planets which are the most likely to host moons. We investigate the tidal evolution of hypothetical moon orbits in systems consisting of a star, one planet and one test moon. We study a few specific cases with ten billion years integration time where the evolution of moon orbits follows one of these three scenarios: (1) “locking”, in which the moon has a stable orbit on a long time scale (& 109 years); (2) “escape scenario” where the moon leaves the planet’s gravitational domain; and (3) “disruption scenario”, in which the moon migrates inwards until it reaches the Roche lobe and becomes disrupted by strong tidal forces. -
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. -
Theory of Stellar Atmospheres
© Copyright, Princeton University Press. No part of this book may be distributed, posted, or reproduced in any form by digital or mechanical means without prior written permission of the publisher. EXTENDED BIBLIOGRAPHY References [1] D. Abbott. The terminal velocities of stellar winds from early{type stars. Astrophys. J., 225, 893, 1978. [2] D. Abbott. The theory of radiatively driven stellar winds. I. A physical interpretation. Astrophys. J., 242, 1183, 1980. [3] D. Abbott. The theory of radiatively driven stellar winds. II. The line acceleration. Astrophys. J., 259, 282, 1982. [4] D. Abbott. The theory of radiation driven stellar winds and the Wolf{ Rayet phenomenon. In de Loore and Willis [938], page 185. Astrophys. J., 259, 282, 1982. [5] D. Abbott. Current problems of line formation in early{type stars. In Beckman and Crivellari [358], page 279. [6] D. Abbott and P. Conti. Wolf{Rayet stars. Ann. Rev. Astr. Astrophys., 25, 113, 1987. [7] D. Abbott and D. Hummer. Photospheres of hot stars. I. Wind blan- keted model atmospheres. Astrophys. J., 294, 286, 1985. [8] D. Abbott and L. Lucy. Multiline transfer and the dynamics of stellar winds. Astrophys. J., 288, 679, 1985. [9] D. Abbott, C. Telesco, and S. Wolff. 2 to 20 micron observations of mass loss from early{type stars. Astrophys. J., 279, 225, 1984. [10] C. Abia, B. Rebolo, J. Beckman, and L. Crivellari. Abundances of light metals and N I in a sample of disc stars. Astr. Astrophys., 206, 100, 1988. [11] M. Abramowitz and I. Stegun. Handbook of Mathematical Functions. (Washington, DC: U.S. Government Printing Office), 1972. -
An Eclipsing Double-Line Spectroscopic Binary at the Stellar/Substellar Boundary in the Upper Scorpius OB Association
A&A 584, A128 (2015) Astronomy DOI: 10.1051/0004-6361/201527464 & c ESO 2015 Astrophysics An eclipsing double-line spectroscopic binary at the stellar/substellar boundary in the Upper Scorpius OB association N. Lodieu1,2, R. Alonso1,2, J. I. González Hernández1,2, R. Sanchis-Ojeda3,, N. Narita4,5,6, Y. Kawashima7, K. Kawauchi8, A. Suárez Mascareño1,2,H.Deeg1,2, J. Prieto Arranz1,2,R.Rebolo1,2, E. Pallé1,2,V.J.S.Béjar1,2, A. Ferragamo1,2, and J. A. Rubiño-Martín1,2 1 Instituto de Astrofísica de Canarias (IAC), Calle Vía Láctea s/n, 38200 La Laguna, Tenerife, Spain e-mail: [email protected] 2 Departamento de Astrofísica, Universidad de La Laguna (ULL), 38206 La Laguna, Tenerife, Spain 3 Department of Astronomy, University of California, Berkeley, CA 94720, USA 4 National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, 181-8588 Tokyo, Japan 5 Astrobiology Center, National Institutes of Natural Sciences, 2-21-1 Osawa, Mitaka, 181-8588 Tokyo, Japan 6 SOKENDAI (The Graduate University for Advanced Studies), Shonan Village, Hayama, 240-0193 Kanagawa, Japan 7 Department of Earth and Planetary Science, The University of Tokyo, 7-3-1 Bunkyo-ku, 113-0033 Tokyo, Japan 8 Department of Earth and Planetary Sciences, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, 152-8551 Tokyo, Japan Received 28 September 2015 / Accepted 9 November 2015 ABSTRACT Aims. We aim at constraining evolutionary models at low mass and young ages by identifying interesting transiting system members of the nearest OB association to the Sun, Upper Scorpius (USco), which has been targeted by the Kepler mission. -
A New Generation of Cool White Dwarf Atmosphere Models. I
Accepted for publication in The Astrophysical Journal Preprint typeset using LATEX style emulateapj v. 08/22/09 A NEW GENERATION OF COOL WHITE DWARF ATMOSPHERE MODELS. I. THEORETICAL FRAMEWORK AND APPLICATIONS TO DZ STARS S. Blouin1, P. Dufour1, and N.F. Allard2,3 Accepted for publication in The Astrophysical Journal ABSTRACT The photospheres of the coolest helium-atmosphere white dwarfs are characterized by fluid-like densities. Under those conditions, standard approximations used in model atmosphere codes are no longer appropriate. Unfortunately, the majority of cool He-rich white dwarfs show no spectral features, giving us no opportunities to put more elaborate models to the test. In the few cases where spectral features are observed (such as in cool DQ or DZ stars), current models completely fail to reproduce the spectroscopic data, signaling shortcomings in our theoretical framework. In order to fully trust parameters derived solely from the energy distribution, it is thus important to at least succeed in reproducing the spectra of the few coolest stars exhibiting spectral features, especially since such stars possess even less extreme physical conditions due to the presence of heavy elements. In this paper, we revise every building block of our model atmosphere code in order to eliminate low-density approximations. Our updated white dwarf atmosphere code incorporates state-of-the-art constitutive physics suitable for the conditions found in cool helium-rich stars (DC and DZ white dwarfs). This includes new high-density metal line profiles, nonideal continuum opacities, an accurate equation of state and a detailed description of the ionization equilibrium. In particular, we present new ab initio calculations to assess the ionization equilibrium of heavy elements (C, Ca, Fe, Mg and Na) in a dense helium medium and show how our improved models allow us to achieve better spectral fits for two cool DZ stars, Ross 640 and LP 658-2. -
Modern Physics
REVIEWS OF MODERN PHYSICS VoLUME 29, NuMBER 4 OcroBER, 1957 Synthesis of the Elements in Stars* E. MARGARET BURBIDGE, G. R. BURBIDGE, WILLIAM: A. FOWLER, AND F. HOYLE Kellogg Radiation1Laboratory, California Institute of Technology, and M aunt Wilson and Palomar Observatories, Carnegie Institution of Washington, California Institute of Technology, Pasadena, California "It is the stars, The stars above us, govern our conditions"; (King Lear, Act IV, Scene 3) but perhaps "The fault, dear Brutus, is not in our stars, But in ourselves," (Julius Caesar, Act I, Scene 2) TABLE OF CONTENTS Page I. Introduction ...............................................................· ............... 548 A. Element Abundances and Nuclear Structure. 548 B. Four Theories of the Origin of the Elements ............................................... 550 C. General Features of Stellar Synthesis ..................................................... 550 II. Physical Processes Involved in Stellar Synthesis, Their Place of Occurrence, and the Time-Scales Associated with Them ...............· ..................... · ................................. 551 A. Modes of Element Synthesis ............................................................. 551 B. Method of Assignment of Isotopes among Processes (i) to (viii) .............................. 553 C. Abundances and Synthesis Assignments Given in the Appendix. 555 D. Time-Scales for Different Modes of Synthesis .............................................. 556 III. Hydrogen Burning, Helium Burning, the a Process,