Massive Spectroscopic Surveys of the Distant Universe, the Milky Way Galaxy, and Extra-Solar Planetary Systems1
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Set 4: Active Galaxies
Set 4: Active Galaxies Phenomenology • History: Seyfert in the 1920’s reported that a small fraction (few tenths of a percent) of galaxies have bright nuclei with broad emission lines. 90% are in spiral galaxies • Seyfert galaxies categorized as 1 if emission lines of HI, HeI and HeII are very broad - Doppler broadening of 1000-5000 km/s and narrower forbidden lines of ∼ 500km/s. Variable. Seyfert 2 if all lines are ∼ 500km/s. Not variable. • Both show a featureless continuum, for Seyfert 1 often more luminous than the whole galaxy • Seyferts are part of a class of galaxies with active galactic nuclei (AGN) • Radio galaxies mainly found in ellipticals - also broad and narrow line - extremely bright in the radio - often with extended lobes connected to center by jets of ∼ 50kpc in extent Radio Galaxy 3C31, NGC 383 Phenomenology • Quasars discovered in 1960 by Matthews and Sandage are extremely distant, quasi-starlike, with broad emission lines. Faint fuzzy halo reveals the parent galaxy of extremely luminous object 38−41 11−14 - visible luminosity L ∼ 10 W or ∼ 10 L • Quasars can be both radio loud (QSR) and quiet (QSO) • Blazars (BL Lac) highly variable AGN with high degree of polarization, mostly in ellipticals • ULIRGs - ultra luminous infrared galaxies - possibly dust enshrouded AGN (alternately may be starburst) • LINERS - similar to Seyfert 2 but low ionization nuclear emission line region - low luminosity AGN with strong emission lines of low ionization species Spectrum . • AGN share a basic general form for their continuum emission • Flat broken power law continuum - specific flux −α Fν / ν . -
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. -
Chemo-Kinematics of the Milky Way from the SDSS-III MARVELS Survey
MNRAS 000,1–22 (2018) Preprint 6 October 2020 Compiled using MNRAS LATEX style file v3.0 Chemo-kinematics of the Milky Way from the SDSS-III MARVELS Survey Nolan Grieves,1¢ Jian Ge,1 Neil Thomas,2 Kevin Willis,1 Bo Ma,1 Diego Lorenzo-Oliveira,3,4 A. B. A. Queiroz,5,4 Luan Ghezzi,6 Cristina Chiappini,7,4 Friedrich Anders,7,4 Letícia Dutra-Ferreira,5,4 Gustavo F. Porto de Mello,8,4 Basílio X. Santiago,5,4 Luiz N. da Costa,6,4 Ricardo L. C. Ogando,6,4 E. F. del Peloso,4 Jonathan C. Tan,9,1 Donald P. Schneider,10,11 Joshua Pepper,12 Keivan G. Stassun,13 Bo Zhao,1 Dmitry Bizyaev,14,15 and Kaike Pan14 1Department of Astronomy, University of Florida, Gainesville, FL 32611, USA 2Department of Astronautical Engineering, United States Air Force Academy, CO 80840, USA 3Universidade de São Paulo, Departamento de Astronomia IAG/USP, Rua do Matão 1226, Cidade Universitária, São Paulo, SP 05508-900, Brazil 4Laboratório Interinstitucional de e-Astronomia-LIneA, Rua Gereral José Cristino 77, São Cristóvão, Rio de Janeiro, RJ 20921-400, Brazil 5Instituto de Física, Universidade Federal do Rio Grande do Sul, Caixa Postal 15051,Porto Alegre, RS - 91501-970, Brazil 6Observatório Nacional, Rua General José Cristino 77, São Cristóvão, Rio de Janeiro, RJ 20921-400, Brazil 7Leibniz-Institut für Astrophysik Potsdam, An der Sternwarte 16, 14482 Potsdam, Germany 8Observatório do Valongo, Universidade Federal do Rio de Janeiro, Ladeira do Pedro Antônio 43, Rio de Janeiro, RJ 20080-090, Brazil 9Department of Astronomy, University of Virginia, Charlottesville, VA 22904 10Department of Astronomy and Astrophysics, The Pennsylvania State University, University Park, PA 16802 11Center for Exoplanets and Habitable Worlds, The Pennsylvania State University, University Park, PA 16802 12Department of Physics, Lehigh University, 16 Memorial Drive East, Bethlehem, PA, 18015, USA 13Vanderbilt University, Physics & Astronomy Department, 6301 Stevenson Center Ln., Nashville, TN 37235 14Apache Point Observatory and New Mexico State University, P.O. -
Resolving the Radio Loud/Radio Quiet Dichotomy Without Thick Disks David
Resolving the radio loud/radio quiet dichotomy without thick disks David Garofalo Department of Physics, Kennesaw State University, Marietta GA 30060, USA Abstract Observations of radio loud active galaxies in the XMM-Newton archive by Mehdipour & Costantini show a strong anti-correlation between the column density of the ionized wind and the radio loudness parameter, providing evidence that jets may thrive in thin disks. This is in contrast with decades of analytic and numerical work suggesting jet formation is contingent on the presence of an inner, geometrically thick disk structure, which serves to both collimate and accelerate the jet. Thick disks emerge in radiatively inefficient disks which are associated with sub-Eddington as well as super-Eddington accretion regimes yet we show that the inverse correlation between winds and jets survives where it should not, namely in a luminosity regime normally attributed to radio quiet active galaxies which are modeled with thin disks. This along with other lines of evidence argues against thick disks as the foundation behind the radio loud/radio quiet dichotomy, opening up the possibility that jetted versus non jetted black holes may be understood within the context of radiatively efficient thin disk accretion. 1. Introduction Sikora et al (2007) explored the inverse correlation between radio loudness and Eddington accretion rate for a large sample of active galaxies (AGN) including Seyfert galaxies and LINERs, optically selected quasars, FRI radio galaxies, FRII quasars, and broad line radio galaxies. Despite a clear dichotomy in radio loudness between objects referred to as radio loud and those as radio quiet, the data was insufficiently detailed to shed light on the jet-disk connection near the Eddington limit where we traditionally model the radio quiet subset of the AGN family. -
Formation of Disc Galaxies from Cosmological Simulations: Galactic Outflows and Chemical Evolution
Scuola Internazionale Superiore di Studi Avanzati - Trieste Formation of disc galaxies from cosmological simulations: galactic outflows and chemical evolution Author: Milena Valentini Supervisors: Prof. Stefano Borgani, Prof. Alessandro Bressan, Dr. Giuseppe Murante International School for Advanced Studies SISSA/ISAS A thesis submitted in fulfilment of the requirements for the degree of Doctor Philosophiae in ASTROPHYSICS and COSMOLOGY October 2018 SISSA - Via Bonomea 265 - 34136 TRIESTE - ITALY To Nicola Abstract In this Thesis, I study the formation of late-type galaxies and the role that feedback from stars and supermassive black holes (SMBHs) plays in galaxy evolution across cosmic time. By carrying out cosmological hydrodynamical simulations, I investigate how different processes, such as the cosmological gas accretion from the large scale environment, star formation and chemical enrichment, stellar and AGN (Active Galactic Nucleus) feedback, affect the early stages of forming galaxies and contribute to determine their present-day properties. Driven by the challenging task of simulating late-type galaxies with a limited bulge and a dominant disc in a cosmological context, I study the impact of galactic outflow modelling on the formation and evolution of a disc galaxy. I find that galactic outflows regulate the timing of gas accretion and determine the star formation history of the forming galaxy. Also, I quantify the strong interplay between the adopted hydrodynamical scheme and the sub-resolution model describing star formation and stellar feedback. Throughout this Thesis, I devote particular emphasis to connect chemical evolution and gas dynamics, in order to interpret observations of metal abundance in the interstellar medium (ISM) and circumgalactic medium (CGM). -
Powerful Jets from Radiatively Efficient Disks, a Decades-Old Unresolved Problem in High Energy Astrophysics
galaxies Article Powerful Jets from Radiatively Efficient Disks, a Decades-Old Unresolved Problem in High Energy Astrophysics Chandra B. Singh 1,*,†, David Garofalo 2,† and Benjamin Lang 3 1 South-Western Institute for Astronomy Research, Yunnan University, University Town, Chenggong, Kunming 650500, China 2 Department of Physics, Kennesaw State University, Marietta, GA 30060, USA; [email protected] 3 Department of Physics & Astronomy, California State University, Northridge, CA 91330, USA; [email protected] * Correspondence: [email protected] † These authors contributed equally to this work. Abstract: The discovery of 3C 273 in 1963, and the emergence of the Kerr solution shortly thereafter, precipitated the current era in astrophysics focused on using black holes to explain active galactic nuclei (AGN). But while partial success was achieved in separately explaining the bright nuclei of some AGN via thin disks, as well as powerful jets with thick disks, the combination of both powerful jets in an AGN with a bright nucleus, such as in 3C 273, remained elusive. Although numerical simulations have taken center stage in the last 25 years, they have struggled to produce the conditions that explain them. This is because radiatively efficient disks have proved a challenge to simulate. Radio quasars have thus been the least understood objects in high energy astrophysics. But recent simulations have begun to change this. We explore this milestone in light of scale-invariance and show that transitory jets, possibly related to the jets seen in these recent simulations, as some have proposed, cannot explain radio quasars. We then provide a road map for a resolution. -
The Milky Way Tomography with SDSS I. Stellar Number Density
The Astrophysical Journal, 673:864Y914, 2008 February 1 A # 2008. The American Astronomical Society. All rights reserved. Printed in U.S.A. THE MILKY WAY TOMOGRAPHY WITH SDSS. I. STELLAR NUMBER DENSITY DISTRIBUTION Mario Juric´,1,2 Zˇ eljko Ivezic´,3 Alyson Brooks,3 Robert H. Lupton,1 David Schlegel,1,4 Douglas Finkbeiner,1,5 Nikhil Padmanabhan,4,6 Nicholas Bond,1 Branimir Sesar,3 Constance M. Rockosi,3,7 Gillian R. Knapp,1 James E. Gunn,1 Takahiro Sumi,1,8 Donald P. Schneider,9 J. C. Barentine,10 Howard J. Brewington,10 J. Brinkmann,10 Masataka Fukugita,11 Michael Harvanek,10 S. J. Kleinman,10 Jurek Krzesinski,10,12 Dan Long,10 Eric H. Neilsen, Jr.,13 Atsuko Nitta,10 Stephanie A. Snedden,10 and Donald G. York14 Received 2005 October 21; accepted 2007 September 6 ABSTRACT Using the photometric parallax method we estimate the distances to 48 million stars detected by the Sloan Digital Sky Survey (SDSS) and map their three-dimensional number density distribution in the Galaxy. The currently avail- able data sample the distance range from 100 pc to 20 kpc and cover 6500 deg2 of sky, mostly at high Galactic lati- tudes (jbj > 25). These stellar number density maps allow an investigation of the Galactic structure with no a priori assumptions about the functional form of its components. The data show strong evidence for a Galaxy consisting of an oblate halo, a disk component, and a number of localized overdensities. The number density distribution of stars as traced by M dwarfs in the solar neighborhood (D < 2 kpc) is well fit by two exponential disks (the thin and thick disk) with scale heights and lengths, bias corrected for an assumed 35% binary fraction, of H1 ¼ 300 pc and L1 ¼ 2600 pc, and H2 ¼ 900 pc and L2 ¼ 3600 pc, and local thick-to-thin disk density normalization thick(R )/thin(R ) ¼ 12%. -
The Age of the Galaxy's Thick Disk
The Ages of Stars Proceedings IAU Symposium No. 258, 2008 c 2009 International Astronomical Union E.E. Mamajek, D.R. Soderblom & R.F.G. Wyse, eds. doi:10.1017/S1743921309031676 The age of the Galaxy’s thick disk Sofia Feltzing1† and Thomas Bensby2 1 Lund Observatory, Box 43, SE-22100, Lund, Sweden email: [email protected] 2 European Southern Observatory, Alonso de Cordova 3107, Vitacura, Casilla 19001, Santiago, Chile email: [email protected] Abstract. We discuss the age of the stellar disks in the solar neighborhood. After reviewing the various methods for age dating, we discuss current estimates of the ages of both the thin- and the thick disks. We present preliminary results for kinematically-selected stars that belong to the thin- as well as the thick disk. All of these dwarf and sub-giant stars have been studied spectroscopically and we have derived both elemental abundances as well as ages for them. A general conclusion is that in the solar neighborhood, on average, the thick disk is older than the thin disk. However, we caution that the exclusion of stars with effective temperatures around 6500 K might result in a biased view of the full age distribution for the stars in the thick disk. Keywords. Galaxy: structure, Galaxy: disk, kinematics and dynamics, solar neighborhood, Hertzsprung-Russell diagram, stars: late-type 1. Introduction The age of a stellar population can be determined in several ways. For groups of stars, isochrones may be fitted to the stellar sequence in the Hertzsprung-Russell diagram (HRD; see, e.g., Schuster et al. -
Stacking Emission Lines from Distant Galaxies
DF A study of galaxy evolution: stacking emission lines from distant galaxies JEAN-BAPTISTE JOLLY Department of Space Earth and Environment CHALMERS UNIVERSITY OF TECHNOLOGY Gothenburg, Sweden 2019 Thesis for the degree of Licentiate of Engineering A study of galaxy evolution: stacking emission lines from distant galaxies Jean-Baptiste Jolly DF Department of Space Earth and Environment Division of Astronomy and Plasma Physics Chalmers University of Technology Gothenburg, Sweden 2019 A study of galaxy evolution: stacking emission lines from distant galaxies Jean-Baptiste Jolly © Jean-Baptiste Jolly, 2019. Division of Astronomy and Plasma Physics Department of Space Earth and Environment Chalmers University of Technology SE-412 96 Gothenburg Telephone +46 31 772 1000 Contact information: Jean-Baptiste Jolly Onsala Space Observatory Chalmers University of Technology SE–439 92 Onsala, Sweden Phone: +46 (0)31 772 55 44 Email: [email protected] Cover image: This image from the NASA/ESA Hubble Space Telescope shows the galaxy cluster MACSJ0717.5+3745. This is one of six being studied by the Hub- ble Frontier Fields programme, which together have produced the deepest images of gravitational lensing ever made. Due to the huge mass of the cluster it is bending the light of background objects, acting as a magnifying lens. It is one of the most massive galaxy clusters known, and it is also the largest known gravitational lens. Of all of the galaxy clusters known and measured, MACS J0717 lenses the largest area of the sky. Credit: NASA, ESA and the HST Frontier Fields team (STScI) Printed by Chalmers Reproservice Gothenburg, Sweden 2019 A study of galaxy evolution: stacking emission lines from distant galaxies Jean-Baptiste Jolly Department of Space Earth and Environment Chalmers University of Technology Abstract To draw up a thorough description of galaxy evolution exhaustive observations are needed, of distant but mainly of faint galaxies. -
The Galaxy in Context: Structural, Kinematic & Integrated Properties
The Galaxy in Context: Structural, Kinematic & Integrated Properties Joss Bland-Hawthorn1, Ortwin Gerhard2 1Sydney Institute for Astronomy, School of Physics A28, University of Sydney, NSW 2006, Australia; email: [email protected] 2Max Planck Institute for extraterrestrial Physics, PO Box 1312, Giessenbachstr., 85741 Garching, Germany; email: [email protected] Annu. Rev. Astron. Astrophys. 2016. Keywords 54:529{596 Galaxy: Structural Components, Stellar Kinematics, Stellar This article's doi: 10.1146/annurev-astro-081915-023441 Populations, Dynamics, Evolution; Local Group; Cosmology Copyright c 2016 by Annual Reviews. Abstract All rights reserved Our Galaxy, the Milky Way, is a benchmark for understanding disk galaxies. It is the only galaxy whose formation history can be stud- ied using the full distribution of stars from faint dwarfs to supergiants. The oldest components provide us with unique insight into how galaxies form and evolve over billions of years. The Galaxy is a luminous (L?) barred spiral with a central box/peanut bulge, a dominant disk, and a diffuse stellar halo. Based on global properties, it falls in the sparsely populated \green valley" region of the galaxy colour-magnitude dia- arXiv:1602.07702v2 [astro-ph.GA] 5 Jan 2017 gram. Here we review the key integrated, structural and kinematic pa- rameters of the Galaxy, and point to uncertainties as well as directions for future progress. Galactic studies will continue to play a fundamen- tal role far into the future because there are measurements that can only be made in the near field and much of contemporary astrophysics depends on such observations. 529 Redshift (z) 20 10 5 2 1 0 1012 1011 ) ¯ 1010 M ( 9 r i 10 v 8 M 10 107 100 101 102 ) c p 1 k 10 ( r i v r 100 10-1 0.3 1 3 10 Time (Gyr) Figure 1 Left: The estimated growth of the Galaxy's virial mass (Mvir) and radius (rvir) from z = 20 to the present day, z = 0. -
New Front of Exoplanetary Science: High Dispersion Coronagraphy (HDC)
New Front of Exoplanetary Science: High Dispersion Coronagraphy (HDC) Ji Wang Caltech Transmission Spectroscopy Fischer et al. 2016 8/1/17 Knutson et al. 2007 Cloud and Haze Sing et al. 2011 Sing et al. 2016 Kreidberg et al. 2014 8/1/17 High Resolution Spectroscopy Wyttenbach et al. 2015 HD 189733b See also Khalafinejad et al. 2016 Atmospheric Composition From High- Resolution Spectroscopy HD 209458, Snellen et al. 2010 8/1/17 Planet Rotation – Beta Pic b Snellen et al. 2014 Dashed - Instrument Profile Solid – Measured Line Profile Doppler Imaging – Luhman 16 A & B DeViation from mean line profile Vs. time CCloud map of Lunman 16 B Luhman 16 B (Crossfield et al. 2014) Detection of H2O and CO on HR 8799 c Keck OSIRIS Konopacky et al. 2013 8/1/17 High Dispersion Coronagraphy Snellen et al. 2015 Keck NIRSPEC Keck NIRC2 Vortex 8/1/17 Keck Planet Imager and Characterizer PI: D. Mawet (Caltech) • Upgrade to Keck II AO and instrument suite: – L-band Vortex coronagraph in NIRC2 - deployed – IR PyWFS – funded (NSF) – SMF link to upgraded NIRSPEC (FIU) - funded (HSF & NSF) – High contrast FIU – seeking funding – MODIUS: New fiber-fed, Multi-Object Diffraction limited IR Ultra-high resolution (R~150k-200k) Spectrograph – design study encouraged by KSSC • Pathfinder to ELT planet imager exploring new high contrast imaging/spectroscopy instrument paradigms: – Decouple search and discoVery from characterization: specialized module/strategy for each task – New hybrid coronagraph designs: e.g. apodized vortex – Wavefront control: e.g. speckle nulling on SMF HDC Instruments • CRIRES • SPHERE + ESPRESSO • SCExAO + IRD • MagAO-X + RHEA • Keck Planet Imager and Characterizer (KPIC) Science cases for HDC • Planet detection and confirmation at moderate contrast from ground • Detecting molecular species in planet atmospheres • Measuring planet rotation • Measuring cloud map for brown dwarfs and exoplanets HDC Simulator Template Matching Mawet et al. -
The Discovery of Segue 2: a Prototype of the Population of Satellites of Satellites
Mon. Not. R. Astron. Soc. 397, 1748–1755 (2009) doi:10.1111/j.1365-2966.2009.15106.x The discovery of Segue 2: a prototype of the population of satellites of satellites V. Belokurov,1 M. G. Walker,1 N. W. Evans,1 G. Gilmore,1 M. J. Irwin,1 M. Mateo,2 L. Mayer,3 E. Olszewski,4 J. Bechtold4 and T. Pickering5 1Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA 2Department of Astronomy, University of Michigan, Ann Arbor, MI 48109, USA 3Institute for Theoretical Physics, University of Zurich,¨ CH-8057 Zurich,¨ Switzerland 4Steward Observatory, University of Arizona, Tucson, AZ 85721, USA 5MMT Observatory, University of Arizona, Tucson, AZ 85271, USA Accepted 2009 May 12. Received 2009 April 23; in original form 2009 March 3 ABSTRACT We announce the discovery of a new Milky Way satellite Segue 2 found in the data of the Sloan Extension for Galactic Understanding and Exploration (SEGUE). We followed this up with deeper imaging and spectroscopy on the Multiple Mirror Telescope (MMT). From this, we derive a luminosity of Mv =−2.5, a half-light radius of 34 pc and a systemic velocity of ∼−40 km s−1. Our data also provide evidence for a stream around Segue 2 at a similar heliocentric velocity, and the SEGUE data show that it is also present in neighbouring fields. We resolve the velocity dispersion of Segue 2 as 3.4 km s−1 and the possible stream as ∼7kms−1. This object shows points of comparison with other recent discoveries, Segue 1, Boo II and Coma.