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Université De Montréal Relevé Polarimétrique D'étoiles Candidates
Université de Montréal Relevé polarimétrique d’étoiles candidates pour des disques de débris par Amélie Simon Département de physique Faculté des arts et des sciences Mémoire présenté à la Faculté des études supérieures en vue de l’obtention du grade de Maître ès sciences (M.Sc.) en physique Août, 2010 c Amélie Simon, 2010 Université de Montréal Faculté des études supérieures Ce mémoire intitulé: Relevé polarimétrique d’étoiles candidates pour des disques de débris présenté par: Amélie Simon a été évalué par un jury composé des personnes suivantes: Serge Demers, président-rapporteur Pierre Bastien, directeur de recherche Gilles Fontaine, membre du jury Mémoire accepté le: Sommaire Le relevé DEBRIS est effectué par le télescope spatial Herschel. Il permet d’échantillonner les disques de débris autour d’étoiles de l’environnement solaire. Dans la première partie de ce mémoire, un relevé polarimétrique de 108 étoiles des candidates de DEBRIS est présenté. Utilisant le polarimètre de l’Observatoire du Mont-Mégantic, des observations ont été effec- tuées afin de détecter la polarisation due à la présence de disques de débris. En raison d’un faible taux de détection d’étoiles polarisées, une analyse statistique a été réalisée dans le but de comparer la polarisation d’étoiles possédant un excès dans l’infrarouge et la polarisation de celles n’en possédant pas. Utilisant la théorie de diffusion de Mie, un modèle a été construit afin de prédire la polarisation due à un disque de débris. Les résultats du modèle sont cohérents avec les observations. La deuxième partie de ce mémoire présente des tests optiques du polarimètre POL-2, construit à l’Université de Montréal. -
Naming the Extrasolar Planets
Naming the extrasolar planets W. Lyra Max Planck Institute for Astronomy, K¨onigstuhl 17, 69177, Heidelberg, Germany [email protected] Abstract and OGLE-TR-182 b, which does not help educators convey the message that these planets are quite similar to Jupiter. Extrasolar planets are not named and are referred to only In stark contrast, the sentence“planet Apollo is a gas giant by their assigned scientific designation. The reason given like Jupiter” is heavily - yet invisibly - coated with Coper- by the IAU to not name the planets is that it is consid- nicanism. ered impractical as planets are expected to be common. I One reason given by the IAU for not considering naming advance some reasons as to why this logic is flawed, and sug- the extrasolar planets is that it is a task deemed impractical. gest names for the 403 extrasolar planet candidates known One source is quoted as having said “if planets are found to as of Oct 2009. The names follow a scheme of association occur very frequently in the Universe, a system of individual with the constellation that the host star pertains to, and names for planets might well rapidly be found equally im- therefore are mostly drawn from Roman-Greek mythology. practicable as it is for stars, as planet discoveries progress.” Other mythologies may also be used given that a suitable 1. This leads to a second argument. It is indeed impractical association is established. to name all stars. But some stars are named nonetheless. In fact, all other classes of astronomical bodies are named. -
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, -
Transition from Spot to Faculae Domination--An Alternate
Astronomy & Astrophysics manuscript no. AC2_arxiv c ESO 2018 October 30, 2018 Transition from spot to faculae domination An alternate explanation for the dearth of intermediate Kepler rotation periods Timo Reinhold1; 2, Keaton J. Bell1; 2, James Kuszlewicz1; 2, Saskia Hekker1; 2, Alexander I. Shapiro1 1 Max-Planck-Institut für Sonnensystemforschung, Justus-von-Liebig-Weg 3, 37077 Göttingen, Germany 2 Stellar Astrophysics Centre, Department of Physics and Astronomy, Aarhus University, 120 Ny Munkegade, Building 1520, DK- 8000 Aarhus C, Denmark Received day month year / Accepted day month year ABSTRACT Context. The study of stellar activity cycles is crucial to understand the underlying dynamo and how it causes magnetic activity signatures such as dark spots and bright faculae. Having knowledge about the dominant source of surface activity might allow us to draw conclusions about the star’s age and magnetic field topology, and to put the solar cycle in context. Aims. We investigate the underlying process that causes magnetic activity by studying the appearance of activity signatures in con- temporaneous photometric and chromospheric time series. Methods. Lomb-Scargle periodograms are used to search for cycle periods present in the photometric and chromospheric time series. To emphasize the signature of the activity cycle we account for rotation-induced scatter in both data sets by fitting a quasi-periodic Gaussian process model to each observing season. After subtracting the rotational variability, cycle amplitudes and the phase differ- ence between the two time series are obtained by fitting both time series simultaneously using the same cycle period. Results. We find cycle periods in 27 of the 30 stars in our sample. -
The Rotation of the Sun As a Star from the Integrated Coronal Green-Line Emission M
ISSN 1063-7729, Astronomy Reports, 2009, Vol. 53, No. 4, pp. 343–354. c Pleiades Publishing, Ltd., 2009. Original Russian Text c M.M. Katsova, I.M. Livshits, J. Sykora, 2009, published in Astronomicheski˘ı Zhurnal, 2009, Vol. 86, No. 4, pp. 379–391. The Rotation of the Sun as a Star from the Integrated Coronal Green-Line Emission M. M. Katsova1, I. M. Livshits2,andJ.Sykora3 1Sternberg Astronomical Institute, Universitetskii pr. 13, Moscow, 119899, Russia 2Pushkov Institute of Terrestrial Magnetism, Ionosphere and Radio Wave Propagation, IZMIRAN, Troitsk, Moscow Region, 142190, Russia 3Institute of Astronomy, Slovak Academy of Sciences, Tatranska Lomnica, Slovakia Received 2008; in final form, July 2, 2008 Abstract—A new representation for the database collected by J. Sykora on the Fe XIV 5303 A˚ line emission observed from 1939 to 2001 is proposed. Observations of the corona at an altitude of 60 above the limb reduced to a single photometric scale provide estimates of the emission of the entire visible solar surface. It is proposed to use the resulting series of daily measurements as a new index of the solar activity, GLSun (The Green-Line Sun). This index is purely observational and is free of the model-dependent limitations imposed on other indices of coronal activity. GLSun describes well both the cyclic activity and the rotational modulation of the brightness of the corona of the Sun as a star. The GLSun series was subject to a wavelet analysis similar to that applied to long-term variations in the chromospheric emission of late active stars. The brightness irregularities in the solar corona rotate more slowly during epochs of high activity than their average rotational speed over the entire observational interval. -
Double and Multiple Star Measurements in the Northern Sky with a 10” Newtonian and a Fast CCD Camera in 2006 Through 2009
Vol. 6 No. 3 July 1, 2010 Journal of Double Star Observations Page 180 Double and Multiple Star Measurements in the Northern Sky with a 10” Newtonian and a Fast CCD Camera in 2006 through 2009 Rainer Anton Altenholz/Kiel, Germany e-mail: rainer.anton”at”ki.comcity.de Abstract: Using a 10” Newtonian and a fast CCD camera, recordings of double and multiple stars were made at high frame rates with a notebook computer. From superpositions of “lucky images”, measurements of 139 systems were obtained and compared with literature data. B/w and color images of some noteworthy systems are also presented. mented double stars, as will be described in the next Introduction section. Generally, I used a red filter to cope with By using the technique of “lucky imaging”, seeing chromatic aberration of the Barlow lens, as well as to effects can strongly be reduced, and not only the reso- reduce the atmospheric spectrum. For systems with lution of a given telescope can be pushed to its limits, pronounced color contrast, I also made recordings but also the accuracy of position measurements can be with near-IR, green and blue filters in order to pro- better than this by about one order of magnitude. This duce composite images. This setup was the same as I has already been demonstrated in earlier papers in used with telescopes under the southern sky, and as I this journal [1-3]. Standard deviations of separation have described previously [1-3]. Exposure times varied measurements of less than +/- 0.05 msec were rou- between 0.5 msec and 100 msec, depending on the tinely obtained with telescopes of 40 or 50 cm aper- star brightness, and on the seeing. -
Events: General Meeting : Monday, May 4, 2015 at the Temecula Library, 30600 Pauba Rd, Rm
The monthly newsletter of the Temecula Valley Astronomers May 2015 Events: General Meeting : Monday, May 4, 2015 at the Temecula Library, 30600 Pauba Rd, Rm. B at 7 pm. Tim Deardorff with his What's Up in the night sky and Curtis Croulet presents the “Illustrated history of the building of Palomar Observatory ”. Curtis is a Master Docent at the Observatory. For the latest on Star Parties, check the web page. APOD: Ring Galaxy AM 0644-741 from Hubble Image Credit: Hubble Heritage Team (AURA / STScI), J. Higdon (Cornell) ESA, NASA WHAT’S INSIDE THIS MONTH: General information: Subscription to the TVA is included in the annual $25 membership (regular members) donation ($9 student; $35 Cosmic Comments family). by President Mark Baker Looking Up President: Mark Baker 951-691-0101 by Curtis Croulet ([email protected]) Art's Night Out Vice President & Facebook: Tim Deardorff 951-775-1036 ([email protected]) by Art Cobb Outreach: John Garrett 951-609-3021 Art's Night Out Reloaded (May 2004) ([email protected]) by Art Cobb Treasurer: Curtis Croulet ([email protected]) For Sale or Trade Secretary: Deborah Cheong ([email protected]) Club Librarian: Bob Leffler 951-541-5400 Send newsletter submissions to Mark DiVecchio ([email protected]) ([email protected]) by the 20th of the month for the next month's issue. Star Party Coordinator: Deborah Cheong ([email protected]) Address renewals or other correspondence to: Like us on Facebook Temecula Valley Astronomers PO Box 1292 Murrieta, CA 92564 Mailing List: [email protected] -
Optical Counterparts of ROSAT X-Ray Sources in Two Selected Fields at Low
Astronomy & Astrophysics manuscript no. sbg˙comsge˙ed c ESO 2018 October 16, 2018 Optical counterparts of ROSAT X-ray sources in two selected fields at low vs. high Galactic latitudes J. Greiner1, G.A. Richter2 1 Max-Planck-Institut f¨ur extraterrestrische Physik, 85740 Garching, Germany 2 Sternwarte Sonneberg, 96515 Sonneberg, Germany Received 14 October 2013 / Accepted 12 August 2014 ABSTRACT Context. The optical identification of large number of X-ray sources such as those from the ROSAT All-Sky Survey is challenging with conventional spectroscopic follow-up observations. Aims. We investigate two ROSAT All-Sky Survey fields of size 10◦× 10◦ each, one at galactic latitude b = 83◦ (26 Com), the other at b = –5◦ (γ Sge), in order to optically identify the majority of sources. Methods. We used optical variability, among other more standard methods, as a means of identifying a large number of ROSAT All- Sky Survey sources. All objects fainter than about 12 mag and brighter than about 17 mag, in or near the error circle of the ROSAT positions, were tested for optical variability on hundreds of archival plates of the Sonneberg field patrol. Results. The present paper contains probable optical identifications of altogether 256 of the 370 ROSAT sources analysed. In partic- ular, we found 126 AGN (some of them may be misclassified CVs), 17 likely clusters of galaxies, 16 eruptive double stars (mostly CVs), 43 chromospherically active stars, 65 stars brighter than about 13 mag, 7 UV Cet stars, 3 semiregular resp. slow irregular variable stars of late spectral type, 2 DA white dwarfs, 1 Am star, 1 supernova remnant and 1 planetary nebula. -
A Survey of Active Galaxies at Tev Photon Energies with the HAWC Gamma-Ray Observatory
Draft version September 22, 2020 Typeset using LATEX default style in AASTeX63 A survey of active galaxies at TeV photon energies with the HAWC gamma-ray observatory A. Albert,1 C. Alvarez,2 J.R. Angeles Camacho,3 J.C. Arteaga-Velazquez,´ 4 K.P. Arunbabu,5 D. Avila Rojas,3 H.A. Ayala Solares,6 V. Baghmanyan,7 E. Belmont-Moreno,3 S.Y. BenZvi,8 C. Brisbois,9 K.S. Caballero-Mora,2 T. Capistran´ ,10 A. Carraminana~ ,10 S. Casanova,7 U. Cotti,4 J. Cotzomi,11 S. Coutino~ de Leon´ ,10 E. De la Fuente,12 B.L. Dingus,1 M.A. DuVernois,13 M. Durocher,1 J.C. D´ıaz-Velez´ ,12 K. Engel,9 C. Espinoza,3 K.L. Fan,9 M. Fernandez´ Alonso,6 H. Fleischhack,14 N. Fraija,15 A. Galvan-G´ amez,´ 15 D. Garc´ıa,3 J.A. Garc´ıa-Gonzalez´ ,3 F. Garfias,15 M.M. Gonzalez´ ,15 J.A. Goodman,9 J.P. Harding,1 S. Hernandez´ ,3 B. Hona,14 D. Huang,14 F. Hueyotl-Zahuantitla,2 P. Huntemeyer,¨ 14 A. Iriarte,15 A. Jardin-Blicq,16, 17, 18 V. Joshi,19 D. Kieda,20 G.J. Kunde,1 A. Lara,5 W.H. Lee,15 H. Leon´ Vargas,3 J.T. Linnemann,21 A.L. Longinotti,10 G. Luis-Raya,22 J. Lundeen,21 K. Malone,1 O. Mart´ınez,11 I. Martinez-Castellanos,9 J. Mart´ınez-Castro,23 J.A. Matthews,24 P. Miranda-Romagnoli,25 J.A. Morales-Soto,4 E. Moreno,11 M. -
Starview Visible Object Listing For: April 15, 2017 Local Time (Z4
StarView Visible Object Listing for: April 15, Local Time (Z4): Lat: Minimum Criteria: 2017 21:30 41.5 Elev: 5° / Mag: 6 Sidereal Time: Lon: Sep: 10 arcmin / Size: 2 09:41 81.5 arcsec Name Con Type Mag Sep/Size Elev 30x75 Little Fish Aur Open Cluster 4.5 39° arcmin kappa Bootes Asellus Tertius Boo Double Star 4.5, 6.6 13.4 arcsec 44° 0.8, 99 Zeta Bootis Boo Double Star 4.6, 4.5 20° arcsec Iota Cancri Can Double Star 4.2, 6.6 30.6 arcsec 73° M44 Beehive Cluster, Praesepe Can Open Cluster 3.7 95 arcmin 65° Eta Cassiopeiae Achrid Cas Double Star 3.4, 7.5 13 arcsec 17° Delta Cephei Cep Star 4 10° 145 Canis Majoris h3945 Cma Double Star 4.8, 6.8 27 arcsec 17° Beta Canis Majoris Murzim Cma Star 2 15° Delta Canis Majoris Wezen Cma Star 1.8 13° Eta Canis Majoris Aludra Cma Star 2.4 12° Gamma Canis Majoris Cma Star 4.1 22° Muliphein M41 Cma Open Cluster 4.5 38 arcmin 16° 24 Comae Berenices Com Double Star 5.2, 6.7 20.3 arcsec 46° 35 Comae Berenices Com Double Star 4.91 29 arcsec 45° Alpha Canum Venaticorum CVn Double Star 2.9, 5.5 19.6 arcsec 53° Cor Caroli Y Cvn La Superba Cvn Star 5 57° Nu Draconis Dra Double Star 4.88 63.4 arcsec 20° 4, 71 Alpha Geminorum Castor Gem Double Star 1.9, 2.9 63° arcsec M35 Collinder 82 Gem Open Cluster 5.3 28 arcmin 43° Globular M13 Hercules Cluster Her 5.8 20 arcmin 14° Cluster M48 Hyd Open Cluster 5.5 54 arcmin 39° Gamma Leporis Lep Double Star 3.7, 6.3 96 arcsec 6° 19 Lyncis Struve 1062 Lyn Double Star 5.6 14.8 arcsec 64° 7.3, 10 Beta Monocerotis Mon Double Star 4.7, 5.2 25° arcsec -
Instruction Manual
iOptron® GEM28 German Equatorial Mount Instruction Manual Product GEM28 and GEM28EC Read the included Quick Setup Guide (QSG) BEFORE taking the mount out of the case! This product is a precision instrument and uses a magnetic gear meshing mechanism. Please read the included QSG before assembling the mount. Please read the entire Instruction Manual before operating the mount. You must hold the mount firmly when disengaging or adjusting the gear switches. Otherwise personal injury and/or equipment damage may occur. Any worm system damage due to improper gear meshing/slippage will not be covered by iOptron’s limited warranty. If you have any questions please contact us at [email protected] WARNING! NEVER USE A TELESCOPE TO LOOK AT THE SUN WITHOUT A PROPER FILTER! Looking at or near the Sun will cause instant and irreversible damage to your eye. Children should always have adult supervision while observing. 2 Table of Content Table of Content ................................................................................................................................................. 3 1. GEM28 Overview .......................................................................................................................................... 5 2. GEM28 Terms ................................................................................................................................................ 6 2.1. Parts List ................................................................................................................................................. -
Starview Visible Object Listing For: May 15, 2017 Local
StarView Visible Object Listing for: May 15, Local Time (Z4): Lat: Minimum Criteria: 2017 21:30 41.5 Elev: 5° / Mag: 6 Sidereal Time: Lon: Sep: 10 arcmin / Size: 2 11:39 81.5 arcsec Name Con Type Mag Sep/Size Elev Little Fish Aur Open Cluster 4.5 30x75 arcmin 18° 4.5, kappa Bootes Asellus Tertius Boo Double Star 13.4 arcsec 62° 6.6 4.6, Zeta Bootis Boo Double Star 0.8, 99 arcsec 42° 4.5 4.2, Iota Cancri Can Double Star 30.6 arcsec 53° 6.6 M44 Beehive Cluster, Praesepe Can Open Cluster 3.7 95 arcmin 47° 3.4, Eta Cassiopeiae Achrid Cas Double Star 13 arcsec 10° 7.5 Delta Cephei Cep Star 4 11° 5.2, 24 Comae Berenices Com Double Star 20.3 arcsec 64° 6.7 35 Comae Berenices Com Double Star 4.91 29 arcsec 64° Alpha Canum Venaticorum 2.9, CVn Double Star 19.6 arcsec 75° Cor Caroli 5.5 Y Cvn La Superba Cvn Star 5 77° 31 Cygni Omicron 1 Cyg Double Star 3.8 9° 32 Cygni Omicron 2 Cyg Double Star 3.98 10° Nu Draconis Dra Double Star 4.88 63.4 arcsec 34° 1.9, Alpha Geminorum Castor Gem Double Star 4, 71 arcsec 41° 2.9 M35 Collinder 82 Gem Open Cluster 5.3 28 arcmin 21° Globular M13 Hercules Cluster Her 5.8 20 arcmin 33° Cluster M48 Hyd Open Cluster 5.5 54 arcmin 23° 19 Lyncis Struve 1062 Lyn Double Star 5.6 14.8 arcsec 47° Epsilon Lyrae The Double Lyr Double Star 4.6, 5, 200,150,64 15° Double 6 arcsec Caldwell 50 Mon Open Cluster 4.8 24 arcmin 13° Christmas Tree Cone Nebula Mon Nebula 3.9 20 arcmin 18° M50 Mon Open Cluster 5.9 16 arcmin 10° Beta Perseus Algol Per Double Star 2.1 5° Double Cluster Caldwell 14, 3.7, Per Open Cluster 60 arcmin 14° Chi Persei 3.8 M47 Pup Open Cluster 5.2 30 arcmin 11° 2.3, Zeta Ursae Majoris Mizar Uma Double Star 14 arcsec 68° 4.0 Alpha Ursae Minoris Polaris Umi Double Star 2.1, 9 18 arcsec 41° End of Listing: 28 of 134 Stars matched criteria Developer: Bruce Bream [email protected] Little Fish (Aur) RA: 5h 18m Mag(v): 4.5 Type: Open Cluster Dec: 33d 30m Size: 30x75 arcmin Distance: ly El: 18° / Az: 299° More than a dozen stars in this cluster.