2 Galaxy Morphology and Classification
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Globular Clusters - Guides to Galaxies
ESO Astrophysics Symposia Globular Clusters - Guides to Galaxies Proceedings of the Joint ESO-FONDAP Workshop on Globular Clusters held in Concepción, Chile, 6-10 March 2006 Bearbeitet von Tom Richtler, Søren Larsen 1. Auflage 2008. Buch. xx, 456 S. Hardcover ISBN 978 3 540 76960 6 Format (B x L): 15,5 x 23,5 cm Gewicht: 871 g Weitere Fachgebiete > Physik, Astronomie > Angewandte Physik > Astrophysik Zu Leseprobe schnell und portofrei erhältlich bei Die Online-Fachbuchhandlung beck-shop.de ist spezialisiert auf Fachbücher, insbesondere Recht, Steuern und Wirtschaft. Im Sortiment finden Sie alle Medien (Bücher, Zeitschriften, CDs, eBooks, etc.) aller Verlage. Ergänzt wird das Programm durch Services wie Neuerscheinungsdienst oder Zusammenstellungen von Büchern zu Sonderpreisen. Der Shop führt mehr als 8 Millionen Produkte. Contents Open Questions in the Globular Cluster – Galaxy Connection Markus Kissler-Patig ............................................ 1 Part I Detailed Studies of Individual Globular Clusters Detailed Chemical Abundances of Extragalactic Globular Clusters Rebecca Bernstein, Andrew McWilliam ............................ 11 Spectroscopic Abundances and Radial Velocities of the Galactic Globular Clusters 2MASS GC01 and 2MASS GC02: Preliminary Results J. Borissova, V.D. Ivanov, A. Stephens, D. Minniti ................ 17 Abundance Anomalies in Galactic Globular Clusters – Looking for the Stellar Culprits C. Charbonnel, N. Prantzos ...................................... 21 Globular Clusters in the Direction of the Inner Galaxy J. Alonso-Garc´ıa, M. Mateo ...................................... 25 Globular Cluster Research with Astronomical Archives Carol A. Christian .............................................. 27 Super-He-Rich Populations in Globular Clusters Chul Chung, Young-Wook Lee, Suk-Jin Yoon, Seok-Joo Joo, and Sang-Il Han ................................................ 29 Testing the BH 176 and Berkeley 29 Association with GASS/Monoceros Peter M. -
Structure and Kinematics of the Virgo Cluster of Galaxies? Olga G
A&A 635, A135 (2020) Astronomy https://doi.org/10.1051/0004-6361/201936172 & c ESO 2020 Astrophysics Structure and kinematics of the Virgo cluster of galaxies? Olga G. Kashibadze1;??, Igor D. Karachentsev1, and Valentina E. Karachentseva2 1 Special Astrophysical Observatory of the Russian Academy of Sciences, Nizhnij Arkhyz, Karachay-Cherkessia 369167, Russia e-mail: [email protected] 2 Main Astronomical Observatory of the National Academy of Sciences, 27 Akademika Zabolotnoho St., Kyiv 03143, Ukraine Received 25 June 2019 / Accepted 24 January 2020 ABSTRACT Aims. This work considers the Virgo cluster of galaxies, focusing on its structure, kinematics, and morphological landscape. Our principal aim is to estimate the virial mass of the cluster. For this purpose, we present a sample of 1537 galaxies with radial velocities −1 ◦ ◦ VLG < 2600 km s situated within a region of ∆SGL = 30 and ∆SGB = 20 around M 87. About half of the galaxies have distance estimates. Methods. We selected 398 galaxies with distances in a (17 ± 5) Mpc range. Based on their 1D and 2D number-density profiles and their radial velocity dispersions, we made an estimate for the virial mass of the Virgo cluster. Results. We identify the infall of galaxies towards the Virgo cluster core along the Virgo Southern Extension filament. From a 1D 14 profile of the cluster, we obtain the virial mass estimate of (6:3 ± 0:9) × 10 M , which is in tight agreement with its mass estimate via the external infall pattern of galaxies. Conclusions. We conclude that the Virgo cluster outskirts between the virial radius and the zero-velocity radius do not contain significant amounts of dark matter beyond the virial radius. -
SMG20 - Twenty Years of Submillimetre Galaxies Star-Forming Galaxies at High Redshifts 31St July – 2Nd August 2017
SMG20 - Twenty years of Submillimetre Galaxies Star-forming galaxies at high redshifts 31st July – 2nd August 2017 Monday 31th July Session 1 Loretta Dunne “Results from Herschel on galaxy formation and evolution” Cardiff Review talk covering results from Herschel on galaxy formation and evolution. James Geach “The SCUBA-2 Cosmology Legacy Survey and beyond” University of Hertfordshire The SCUBA-2 Cosmology Legacy Survey (S2CLS) is the largest 850 mm survey to date, detecting 1000’s of sub-mm sources over about 5 square degrees and providing exceptionally deep 450+850 mm maps in several extragalactic fields. It is enabling detailed studies of the SMG population and feeds directly into ALMA follow-up programmes. Now complete, I will present an overview of S2CLS and highlight some of the key science results so far. I will conclude with a look to the future of large ground-based sub-mm surveys, in particular what could be achieved with a new large single dish located on the Chajnantor Plateau. SMG20 31st July - 2nd August 2017 2 Scott Chapman “Identifying the brightest galaxies in the SCUBA-2 Cosmology Legacy Survey” Dalhousie University Using the SMA and complemented by ALMA in the UDS, we have identified the 120 brightest SCUBA-2 sources in the SCUBA-2 Cosmology Legacy Survey. This consists of all sources with S850mm > 9 mJy, and includes several unlensed sources with single component fluxes close to 20 mJy. Previous studies have had little sta- tistical constraint on the true bright end count, and therefore on the properties of these maximal star formers. Spectroscopic surveys with Keck, Gemini, and VLT have measured redshifts and line properties for about 30% of these sources. -
Central Coast Astronomy Virtual Star Party May 15Th 7Pm Pacific
Central Coast Astronomy Virtual Star Party May 15th 7pm Pacific Welcome to our Virtual Star Gazing session! We’ll be focusing on objects you can see with binoculars or a small telescope, so after our session, you can simply walk outside, look up, and understand what you’re looking at. CCAS President Aurora Lipper and astronomer Kent Wallace will bring you a virtual “tour of the night sky” where you can discover, learn, and ask questions as we go along! All you need is an internet connection. You can use an iPad, laptop, computer or cell phone. When 7pm on Saturday night rolls around, click the link on our website to join our class. CentralCoastAstronomy.org/stargaze Before our session starts: Step 1: Download your free map of the night sky: SkyMaps.com They have it available for Northern and Southern hemispheres. Step 2: Print out this document and use it to take notes during our time on Saturday. This document highlights the objects we will focus on in our session together. Celestial Objects: Moon: The moon 4 days after new, which is excellent for star gazing! *Image credit: all astrophotography images are courtesy of NASA & ESO unless otherwise noted. All planetarium images are courtesy of Stellarium. Central Coast Astronomy CentralCoastAstronomy.org Page 1 Main Focus for the Session: 1. Canes Venatici (The Hunting Dogs) 2. Boötes (the Herdsman) 3. Coma Berenices (Hair of Berenice) 4. Virgo (the Virgin) Central Coast Astronomy CentralCoastAstronomy.org Page 2 Canes Venatici (the Hunting Dogs) Canes Venatici, The Hunting Dogs, a modern constellation created by Polish astronomer Johannes Hevelius in 1687. -
Messier Objects
Messier Objects From the Stocker Astroscience Center at Florida International University Miami Florida The Messier Project Main contributors: • Daniel Puentes • Steven Revesz • Bobby Martinez Charles Messier • Gabriel Salazar • Riya Gandhi • Dr. James Webb – Director, Stocker Astroscience center • All images reduced and combined using MIRA image processing software. (Mirametrics) What are Messier Objects? • Messier objects are a list of astronomical sources compiled by Charles Messier, an 18th and early 19th century astronomer. He created a list of distracting objects to avoid while comet hunting. This list now contains over 110 objects, many of which are the most famous astronomical bodies known. The list contains planetary nebula, star clusters, and other galaxies. - Bobby Martinez The Telescope The telescope used to take these images is an Astronomical Consultants and Equipment (ACE) 24- inch (0.61-meter) Ritchey-Chretien reflecting telescope. It has a focal ratio of F6.2 and is supported on a structure independent of the building that houses it. It is equipped with a Finger Lakes 1kx1k CCD camera cooled to -30o C at the Cassegrain focus. It is equipped with dual filter wheels, the first containing UBVRI scientific filters and the second RGBL color filters. Messier 1 Found 6,500 light years away in the constellation of Taurus, the Crab Nebula (known as M1) is a supernova remnant. The original supernova that formed the crab nebula was observed by Chinese, Japanese and Arab astronomers in 1054 AD as an incredibly bright “Guest star” which was visible for over twenty-two months. The supernova that produced the Crab Nebula is thought to have been an evolved star roughly ten times more massive than the Sun. -
Stellar Tidal Streams As Cosmological Diagnostics: Comparing Data and Simulations at Low Galactic Scales
RUPRECHT-KARLS-UNIVERSITÄT HEIDELBERG DOCTORAL THESIS Stellar Tidal Streams as Cosmological Diagnostics: Comparing data and simulations at low galactic scales Author: Referees: Gustavo MORALES Prof. Dr. Eva K. GREBEL Prof. Dr. Volker SPRINGEL Astronomisches Rechen-Institut Heidelberg Graduate School of Fundamental Physics Department of Physics and Astronomy 14th May, 2018 ii DISSERTATION submitted to the Combined Faculties of the Natural Sciences and Mathematics of the Ruperto-Carola-University of Heidelberg, Germany for the degree of DOCTOR OF NATURAL SCIENCES Put forward by GUSTAVO MORALES born in Copiapo ORAL EXAMINATION ON JULY 26, 2018 iii Stellar Tidal Streams as Cosmological Diagnostics: Comparing data and simulations at low galactic scales Referees: Prof. Dr. Eva K. GREBEL Prof. Dr. Volker SPRINGEL iv NOTE: Some parts of the written contents of this thesis have been adapted from a paper submitted as a co-authored scientific publication to the Astronomy & Astrophysics Journal: Morales et al. (2018). v NOTE: Some parts of this thesis have been adapted from a paper accepted for publi- cation in the Astronomy & Astrophysics Journal: Morales, G. et al. (2018). “Systematic search for tidal features around nearby galaxies: I. Enhanced SDSS imaging of the Local Volume". arXiv:1804.03330. DOI: 10.1051/0004-6361/201732271 vii Abstract In hierarchical models of galaxy formation, stellar tidal streams are expected around most galaxies. Although these features may provide useful diagnostics of the LCDM model, their observational properties remain poorly constrained. Statistical analysis of the counts and properties of such features is of interest for a direct comparison against results from numeri- cal simulations. In this work, we aim to study systematically the frequency of occurrence and other observational properties of tidal features around nearby galaxies. -
April Constellations of the Month
April Constellations of the Month Leo Small Scope Objects: Name R.A. Decl. Details M65! A large, bright Sa/Sb spiral galaxy. 7.8 x 1.6 arc minutes, magnitude 10.2. Very 11hr 18.9m +13° 05’ (NGC 3623) high surface brighness showing good detail in medium sized ‘scopes. M66! Another bright Sb galaxy, only 21 arc minutes from M65. Slightly brighter at mag. 11hr 20.2m +12° 59’ (NGC 3627) 9.7, measuring 8.0 x 2.5 arc minutes. M95 An easy SBb barred spiral, 4 x 3 arc minutes in size. Magnitude 10.5, with 10hr 44.0m +11° 42’ a bright central core. The bar and outer ring of material will require larger (NGC 3351) aperature and dark skies. M96 Another bright Sb spiral, about 42 arc minutes east of M95, but larger and 10hr 46.8m +11° 49’ (NGC 3368) brighter. 6 x 4 arc minutes, magnitude 10.1. Located about 48 arc minutes NNE of M96. This small elliptical galaxy measures M105 only 2 x 2.1 arc minutes, but at mag. 10.3 has very high surface brightness. 10hr 47.8m +12° 35’ (NGC 3379) Look for NGC 3384! (110NGC) and NGC 3389 (mag 11.0 and 12.2) which form a small triangle with M105. NGC 3384! 10hr 48.3m +12° 38’ See comment for M105. The brightest galaxy in Leo, this Sb/Sc spiral galaxy shines at mag. 9.5. Look for NGC 2903!! 09hr 32.2m +21° 30’ a hazy patch 11 x 4.7 arc minutes in size 1.5° south of l Leonis. -
Lecture 6: Galaxy Dynamics (Basic) Elliptical Galaxy Dynamics
Lecture 6: Galaxy Dynamics (Basic) • Basic dynamics of galaxies – Ellipticals, kinematically hot random orbit systems – Spirals, kinematically cool rotating system • Key relations: – The fundamental plane of ellipticals/bulges – The Faber-Jackson relation for ellipticals/bulges – The Tully-Fisher for spirals disks • Using FJ and TF to calculate distances – The extragalactic distance ladder – Examples 1 Elliptical galaxy dynamics • Ellipticals are triaxial spheroids • No rotation, no flattened plane • Typically we can measure a velocity dispersion, σ – I.e., the integrated motions of the stars • Dynamics analogous to a gravitational bound cloud of gas (I.e., an isothermal sphere). • I.e., dp GM(r)ρ(r) HYDROSTATIC − = EQUILIBRIUM dr r2 Check Wikipedia “Hydrostatic PRESSURE FORCE GRAVITATIONAL FORCE Equilibrium” to see PER UNIT VOLUME PER UNIT VOLUME deriiation. € 2 1 Elliptical galaxy dynamics • For an isothermal sphere gas pressure is given by: 2 Reminder from p = ρ(r)σ Thermodynamics: P=nRT/V=ρT, 1 E=(3/2)kT=(1/2)mv^2 ρ(r) ∝ r2 σ 2 GM(r) 2 ⇒ 3 ∝ 4 2σ r r r M(r) = G M(r) ∝σ 2r € 3 € Elliptical galaxy dynamics • As E/S0s are centrally concentrated if σ is measured over sufficient area M(r)=>M, I.e., Total Mass ∝σ 2r • σ is measured from either: – Radial velocity distributions from individual stellar spectra – From line widths€ in integrated galaxy spectra [See Galactic Astronomy, Binney & Merrifield for details on how these are measured in practice] 4 2 Elliptical galaxy dynamices • We have three measureable quantities: – L = luminosity (or magnitude) – Re = effective or half-light radius – σ = velocity dispersion • From these we can derive Σο the central surface brightness (nb: one of these four is redundant as its calculable from the others.) • How are these related observationally and theoretically ? x y • I.e., what does: L ∝ Σ o σ ν look like ? Σο Log logL THE FUNDAMENTAL PLANE € Logσ 5 Fundamental Plane Theory 2 (I.e., stars behaving as if isothermal sphere) IF σν ∝ M Re 2 Surf. -
Isolated Elliptical Galaxies in the Local Universe
A&A 588, A79 (2016) Astronomy DOI: 10.1051/0004-6361/201527844 & c ESO 2016 Astrophysics Isolated elliptical galaxies in the local Universe I. Lacerna1,2,3, H. M. Hernández-Toledo4 , V. Avila-Reese4, J. Abonza-Sane4, and A. del Olmo5 1 Instituto de Astrofísica, Pontificia Universidad Católica de Chile, Av. V. Mackenna 4860, Santiago, Chile e-mail: [email protected] 2 Centro de Astro-Ingeniería, Pontificia Universidad Católica de Chile, Av. V. Mackenna 4860, Santiago, Chile 3 Max Planck Institute for Astronomy, Königstuhl 17, 69117 Heidelberg, Germany 4 Instituto de Astronomía, Universidad Nacional Autónoma de México, A.P. 70-264, 04510 México D. F., Mexico 5 Instituto de Astrofísica de Andalucía IAA – CSIC, Glorieta de la Astronomía s/n, 18008 Granada, Spain Received 26 November 2015 / Accepted 6 January 2016 ABSTRACT Context. We have studied a sample of 89 very isolated, elliptical galaxies at z < 0.08 and compared their properties with elliptical galaxies located in a high-density environment such as the Coma supercluster. Aims. Our aim is to probe the role of environment on the morphological transformation and quenching of elliptical galaxies as a function of mass. In addition, we elucidate the nature of a particular set of blue and star-forming isolated ellipticals identified here. Methods. We studied physical properties of ellipticals, such as color, specific star formation rate, galaxy size, and stellar age, as a function of stellar mass and environment based on SDSS data. We analyzed the blue and star-forming isolated ellipticals in more detail, through photometric characterization using GALFIT, and infer their star formation history using STARLIGHT. -
2) Adolgov-PACTS.Pdf
Primordial black holes, dark matter, and other cosmological puzzles A. D. Dolgov Novosibirsk State University, Novosibirsk, Russia ITEP, Moscow, Russia Particle, Astroparticle, and Cosmology Tallinn Symposium Tallinn, Estonia, June 18-22 2018 A. D. Dolgov PBH, DM, and other cosmological puzzles 19 June 2018 1 / 39 Recent astronomical data, which keep on appearing almost every day, show that the contemporary, z ∼ 0, and early, z ∼ 10, universe is much more abundantly populated by all kind of black holes, than it was expected even a few years ago. They may make a considerable or even 100% contribution to the cosmological dark matter. Among these BH: massive, M ∼ (7 − 8)M , 6 9 supermassive, M ∼ (10 − 10 )M , 3 5 intermediate mass M ∼ (10 − 10 )M , and a lot between and out of the intervals. Most natural is to assume that these black holes are primordial, PBH. Existence of such primordial black holes was essentially predicted a quarter of century ago (A.D. and J.Silk, 1993). A. D. Dolgov PBH, DM, and other cosmological puzzles 19 June 2018 2 / 39 However, this interpretation encounters natural resistance from the astronomical establishment. Sometimes the authors of new discoveries admitted that the observed phenomenon can be the explained by massive BHs, which drove the effect, but immediately retreated, saying that there was no known way to create sufficiently large density of such BHs. A. D. Dolgov PBH, DM, and other cosmological puzzles 19 June 2018 3 / 39 Astrophysical BH versus PBH Astrophysical BHs are results of stellar collapce after a star exhausted its nuclear fuel. -
OBSERVING BASICS by GUY MACKIE
OBSERVING BASICS by GUY MACKIE Observing Reports The colorful and detailed photographs we see of celestial objects are not at all like the ubiquitous "fuzzy blobs" we see at the eyepiece. Nevertheless, you are freezing your buns off and loosing much needed sleep for work, the next day so why not make a description of your observations that will make the hunt worthwhile. Here are some suggestions to fill the empty spaces in your logbook and to imprint the observing experience more deeply in your memory. The Basics Your website www.m51.ca has a downloadable log sheet template that is just super, but you can also make up one for yourself or customize the website version to your own needs. The main things to start your report should be the circumstances under which you observed: Observing Location Time (of observing session and of the observation of each object) Optics (type of instrument, eyepiece, filters, power of magnification) Transparency (page 56 of the Observers Handbook) Seeing (for me this is a subjective rating of the atmospheric stability based on Planet features and double star observations) It is good to know the field of view (FOV) of each of your eyepieces in minutes of degree, then you can estimate the approximate size of the object. The sketchpad I use has the FOV for every eyepiece I use taped to the back, a handy reference. To calculate your field of view there are websites that will punch out the both the magnification and the FOV for most eyepieces. You can do it yourself: With any motor drives turned off, place a star near the celestial equator just outside the field of view in the eyepiece so that it will drift across the middle of the field of view. -
12 Strong Gravitational Lenses
12 Strong Gravitational Lenses Phil Marshall, MaruˇsaBradaˇc,George Chartas, Gregory Dobler, Ard´ısEl´ıasd´ottir,´ Emilio Falco, Chris Fassnacht, James Jee, Charles Keeton, Masamune Oguri, Anthony Tyson LSST will contain more strong gravitational lensing events than any other survey preceding it, and will monitor them all at a cadence of a few days to a few weeks. Concurrent space-based optical or perhaps ground-based surveys may provide higher resolution imaging: the biggest advances in strong lensing science made with LSST will be in those areas that benefit most from the large volume and the high accuracy, multi-filter time series. In this chapter we propose an array of science projects that fit this bill. We first provide a brief introduction to the basic physics of gravitational lensing, focusing on the formation of multiple images: the strong lensing regime. Further description of lensing phenomena will be provided as they arise throughout the chapter. We then make some predictions for the properties of samples of lenses of various kinds we can expect to discover with LSST: their numbers and distributions in redshift, image separation, and so on. This is important, since the principal step forward provided by LSST will be one of lens sample size, and the extent to which new lensing science projects will be enabled depends very much on the samples generated. From § 12.3 onwards we introduce the proposed LSST science projects. This is by no means an exhaustive list, but should serve as a good starting point for investigators looking to exploit the strong lensing phenomenon with LSST.