Observations of Group Galaxies 1 Kavli Institute For
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Thesis University of Western Australia
Kinematic and Environmental Regulation of Atomic Gas in Galaxies Jie Li March 2019 Master Thesis University of Western Australia Supervisors: Dr. Danail Obreschkow Dr. Claudia Lagos Dr. Charlotte Welker 20/05/2019 Acknowledgments I would like to thank my supervisors Danail Obreschkow, Claudia Lagos and Charlotte Welker for their guidance and support during this project, Luca Cortese, Robert Dˇzudˇzar and Garima Chauhan for their useful suggestions, my parents for giving me financial support and love, and ICRAR for o↵ering an open and friendly environments. Abstract Recent studies of neutral atomic hydrogen (H i) in nearby galaxies find that all isolated star-forming disk-dominated galaxies, from low-mass dwarfs to massive spirals systems, are H i saturated, in that they carry roughly (within a factor 1.5) as much H i fraction as permitted before this gas becomes gravitationally unstable. By taking this H i saturation for granted, the atomic gas fraction fatm of galactic disks can be predicted as a function of a stability parameter q j/M,whereM and j are the baryonic mass and specific / angular momentum of the disk (Obreschkow et al., 2016). The (logarithmic) di↵erence ∆fq between this predictor and the observed atomic fraction can thus be seen as a physically motivated way of defining a ‘H i deficiency’. While isolated disk galaxies have ∆f 0, q ⇡ objects subject to environmental removal/suppression of H i are expected to have ∆fq > 0. Within this framework, we revisit the H i deficiencies of satellite galaxies in the Virgo cluster (from the VIVA sample), as well as in clusters of the EAGLE simulation. -
Arxiv:0807.3747V2 [Astro-Ph] 13 Sep 2008 Prlsrcuebtltl,I N,Ogigsa Formation
Draft version October 23, 2018 A Preprint typeset using LTEX style emulateapj v. 08/13/06 THE STELLAR POPULATIONS OF STRIPPED SPIRAL GALAXIES IN THE VIRGO CLUSTER Hugh H. Crowl1 and Jeffrey D.P. Kenney Department of Astronomy, Yale University, New Haven, CT 06520 Draft version October 23, 2018 ABSTRACT We present an analysis of the stellar populations of the gas-stripped outer disks of ten Virgo Clus- ter spiral galaxies, utilizing SparsePak integral field spectroscopy on the WIYN 3.5m telescope and GALEX UV photometry. The galaxies in our sample show evidence for being gas-stripped spiral galaxies, with star formation within a truncation radius, and a passive population beyond the trun- cation radius. We find that all of the galaxies with spatially truncated star formation have outer disk stellar populations consistent with star formation ending within the last 500 Myr. The synthe- sis of optical spectroscopy and GALEX observations demonstrate that star formation was relatively constant until the quenching time, after which the galaxies passively evolved. Large starbursts at the time of quenching are excluded for all galaxies, but there is evidence of a modest starburst in at least one galaxy. For approximately half of our galaxies, the timescales derived from our observations are consistent with galaxies being stripped in or near the cluster core, where simple ram-pressure estimates can explain the observed stripping. However, the other half of our sample galaxies were clearly stripped outside the cluster core. Such galaxies provide evidence that the intra-cluster medium is not static and smooth. For three of the most recently stripped galaxies, there are estimates for the stripping timescales from detailed gas stripping simulations. -
Aspects of Supermassive Black Hole Growth in Nearby Active Galactic Nuclei Davide Lena
Rochester Institute of Technology RIT Scholar Works Theses Thesis/Dissertation Collections 4-2015 Aspects of Supermassive Black Hole Growth in Nearby Active Galactic Nuclei Davide Lena Follow this and additional works at: http://scholarworks.rit.edu/theses Recommended Citation Lena, Davide, "Aspects of Supermassive Black Hole Growth in Nearby Active Galactic Nuclei" (2015). Thesis. Rochester Institute of Technology. Accessed from This Dissertation is brought to you for free and open access by the Thesis/Dissertation Collections at RIT Scholar Works. It has been accepted for inclusion in Theses by an authorized administrator of RIT Scholar Works. For more information, please contact [email protected]. Aspects of Supermassive Black Hole Growth in Nearby Active Galactic Nuclei A Search for Recoiling Supermassive Black Holes Gas Kinematics in the Circumnuclear Region of Two Seyfert Galaxies Davide Lena A dissertation submitted in partial fulfillment of the requirements for the degree of Ph.D. in Astrophysical Sciences and Technology in the College of Science, School of Physics and Astronomy Rochester Institute of Technology © D. Lena April, 2015 Cover image: flux map for the [NII]λ6583 emission line in the nuclear region of the Seyfert galaxy NGC 1386. The map was derived from integral field observations performed with the Gemini Multi Object Spectrograph on the Gemini-South Observatory. Certificate of Approval Astrophysical Sciences and Technologies R·I·T College of Science Rochester, NY, USA The Ph.D. Dissertation of DAVIDE LENA has been approved by the undersigned members of the dissertation committee as satisfactory for the degree of Doctor of Philosophy in Astrophysical Sciences and Technology. -
Extraplanar HII Regions in the Edge-On Spiral Galaxies NGC 3628 and NGC 4522? Y
A&A 605, A5 (2017) DOI: 10.1051/0004-6361/201730589 Astronomy & c ESO 2017 Astrophysics Extraplanar HII regions in the edge-on spiral galaxies NGC 3628 and NGC 4522? Y. Stein1, D. J. Bomans1; 2, A. M. N. Ferguson3, and R.-J. Dettmar1; 2 1 Astronomisches Institut (AIRUB), Ruhr-Universität Bochum, Universitätsstrasse 150, 44801 Bochum, Germany e-mail: [email protected] 2 Research Department: Plasmas with Complex Interactions, Ruhr-Universität Bochum, Universitätsstrasse 150, 44801 Bochum, Germany 3 Institute for Astronomy, University of Edinburgh, Blackford Hill, Edinburgh EH9 3HJ, UK Received 9 February 2017 / Accepted 30 May 2017 ABSTRACT Context. Gas infall and outflow are critical for determining the star formation rate and chemical evolution of galaxies but direct measurements of gas flows are difficult to make. Young massive stars and Hii regions in the halos of galaxies are potential tracers for accretion and/or outflows of gas. Aims. Gas phase abundances of three Hii regions in the lower halos of the edge-on galaxies NGC 3628 and NGC 4522 are determined by analyzing optical long-slit spectra. The observed regions have projected distances to the midplane of their host from 1.4 to 3 kpc. Methods. With the measured flux densities of the optical nebular emission lines, we derived the oxygen abundance 12 + log(O/H) for the three extraplanar Hii regions. The analysis was based on one theoretical and two empirical strong-line calibration methods. Results. The resulting oxygen abundances of the extraplanar Hii regions are comparable to the disk Hii regions in one case and are a little lower in the other case. -
Professor Catriona Macleod
RRR | Cover 2015 v2 11/9/16 10:17 AM Page 1 C M Y CM MY CY CMY K Composite RRR 2015 | Features 11/12/16 1:36 PM Page 1 C M Y CM MY CY CMY K RHODES UNIVERSITY RESEARCH REPORT A publication of the Rhodes University Research Office, compiled and edited by Tarryn Gillitt, Busi Goba, Patricia Jacob, Jill Macgregor and Jaine Roberts Design & Layout: Sally Dore Research Office Director: Jaine Roberts [email protected] Tel: +27 (46) 603 8756/7572 www.ru.ac.za Cover: Rhodes University researchers Pam Maseko, Nomalanga Mkhize, Heila Lotz-Sisitka, Ruth Simbao, Anthea Garman and Catriona Macleod Cover Photos: Paul Greenway/www.3pphotography.com RESEARCH REPORT 2015 Composite RRR 2015 | Features 11/12/16 1:36 PM Page 2 C M Y CM MY CY CMY K CONTENTS 01 FOREWORD Dr Sizwe Mabizela, Vice-Chancellor 03 INTRODUCTION Dr Peter Clayton, Deputy Vice-Chancellor: Research & Development 05 TOP 30 RESEARCHERS 06 PHD GRADUATES 11 VICE-CHANCELLOR’S BOOK AWARD Professor Anthea Garman 13 VICE-CHANCELLOR’S DISTINGUISHED SENIOR RESEARCH AWARD Professor Catriona Macleod 15 VICE-CHANCELLOR’S DISTINGUISHED RESEARCH AWARD Dr Adrienne Edkins 17 SARChI CHAIRS Professor Heila Lotz-Sisitka, Professor Ruth Simbao and Dr Adrienne Edkins 23 AFRICAN LANGUAGES, SCHOOL OF LANGUAGES AND LITERATURE Associate Professor Pamela Maseko 25 DEPARTMENT OF HISTORY Dr Nomalanga Mkhize RESEARCH REPORT 2015 Composite RRR 2015 | Features 11/12/16 1:34 PM Page 3 C M Y CM MY CY CMY K RHODES RESEARCH 2015 RESEARCH REPORT DEPARTMENT PUBLICATIONS AFFILIATES, INSTITUTES AND 28 Publications from the Vice-Chancellorate -
Celebrating the Wonder of the Night Sky
Celebrating the Wonder of the Night Sky The heavens proclaim the glory of God. The skies display his craftsmanship. Psalm 19:1 NLT Celebrating the Wonder of the Night Sky Light Year Calculation: Simple! [Speed] 300 000 km/s [Time] x 60 s x 60 m x 24 h x 365.25 d [Distance] ≈ 10 000 000 000 000 km ≈ 63 000 AU Celebrating the Wonder of the Night Sky Milkyway Galaxy Hyades Star Cluster = 151 ly Barnard 68 Nebula = 400 ly Pleiades Star Cluster = 444 ly Coalsack Nebula = 600 ly Betelgeuse Star = 643 ly Helix Nebula = 700 ly Helix Nebula = 700 ly Witch Head Nebula = 900 ly Spirograph Nebula = 1 100 ly Orion Nebula = 1 344 ly Dumbbell Nebula = 1 360 ly Dumbbell Nebula = 1 360 ly Flame Nebula = 1 400 ly Flame Nebula = 1 400 ly Veil Nebula = 1 470 ly Horsehead Nebula = 1 500 ly Horsehead Nebula = 1 500 ly Sh2-106 Nebula = 2 000 ly Twin Jet Nebula = 2 100 ly Ring Nebula = 2 300 ly Ring Nebula = 2 300 ly NGC 2264 Nebula = 2 700 ly Cone Nebula = 2 700 ly Eskimo Nebula = 2 870 ly Sh2-71 Nebula = 3 200 ly Cat’s Eye Nebula = 3 300 ly Cat’s Eye Nebula = 3 300 ly IRAS 23166+1655 Nebula = 3 400 ly IRAS 23166+1655 Nebula = 3 400 ly Butterfly Nebula = 3 800 ly Lagoon Nebula = 4 100 ly Rotten Egg Nebula = 4 200 ly Trifid Nebula = 5 200 ly Monkey Head Nebula = 5 200 ly Lobster Nebula = 5 500 ly Pismis 24 Star Cluster = 5 500 ly Omega Nebula = 6 000 ly Crab Nebula = 6 500 ly RS Puppis Variable Star = 6 500 ly Eagle Nebula = 7 000 ly Eagle Nebula ‘Pillars of Creation’ = 7 000 ly SN1006 Supernova = 7 200 ly Red Spider Nebula = 8 000 ly Engraved Hourglass Nebula -
Probing the Physics of Narrow Line Regions in Active Galaxies II: the Siding Spring Southern Seyfert Spectroscopic Snapshot Survey (S7)
Probing the Physics of Narrow Line Regions in Active Galaxies II: The Siding Spring Southern Seyfert Spectroscopic Snapshot Survey (S7) Michael A. Dopita1,2, Prajval Shastri3, Rebecca Davies1, Lisa Kewley1,4, Elise Hampton1, Julia Scharw¨achter5, Ralph Sutherland1, Preeti Kharb3, Jessy Jose3, Harish Bhatt3, S. Ramya 3, Chichuan Jin6, Julie Banfield7, Ingyin Zaw8, St´ephanie Juneau9, Bethan James10 & Shweta Srivastava11 [email protected] ABSTRACT Here we describe the Siding Spring Southern Seyfert Spectroscopic Snapshot Survey (S7) and present results on 64 galaxies drawn from the first data release. The S7 uses the Wide Field Spectrograph (WiFeS) mounted on the ANU 2.3m telescope located at the Siding Spring Observatory to deliver an integral field of 38×25 arcsec at a spectral resolution of R = 7000 in the red (530−710nm), and R = 3000 in the blue (340 − 560nm). From these data cubes we have extracted the Narrow Line Region (NLR) spectra from a 4 arc sec aperture centred on the nucleus. We also determine the Hβ and [O III] λ5007 fluxes in the narrow lines, the nuclear reddening, the reddening-corrected relative intensities of the observed emission lines, and the Hβ and [O III] λ5007 luminosities determined 1RSAA, Australian National University, Cotter Road, Weston Creek, ACT 2611, Australia 2Astronomy Department, King Abdulaziz University, P.O. Box 80203, Jeddah, Saudi Arabia 3Indian Institute of Astrophysics, Koramangala 2B Block, Bangalore 560034, India 4Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI, USA 5LERMA, Observatoire de Paris, CNRS, UMR 8112, 61 Avenue de l’Observatoire, 75014, Paris, France 6Qian Xuesen Laboratory for Space Technology, Beijing, China 7CSIRO Astronomy & Space Science, P.O. -
The Virgo Supercluster
12-1 How Far Away Is It – The Virgo Supercluster The Virgo Supercluster {Abstract – In this segment of our “How far away is it” video book, we cover our local supercluster, the Virgo Supercluster. We begin with a description of the size, content and structure of the supercluster, including the formation of galaxy clusters and galaxy clouds. We then take a look at some of the galaxies in the Virgo Supercluster including: NGC 4314 with its ring in the core, NGC 5866, Zwicky 18, the beautiful NGC 2841, NGC 3079 with is central gaseous bubble, M100, M77 with its central supermassive black hole, NGC 3949, NGC 3310, NGC 4013, the unusual NGC 4522, NGC 4710 with its "X"-shaped bulge, and NGC 4414. At this point, we have enough distant galaxies to formulate Hubble’s Law and calculate Hubble’s Red Shift constant. From a distance ladder point of view, once we have the Hubble constant, and we can measure red shift, we can calculate distance. So we add Red Shift to our ladder. Then we continue with galaxy gazing with: NGC 1427A, NGC 3982, NGC 1300, NGC 5584, the dusty NGC 1316, NGC 4639, NGC 4319, NGC 3021 with is large number of Cepheid variables, NGC 3370, NGC 1309, and 7049. We end with a review of the distance ladder now that Red Shift has been added.} Introduction [Music: Antonio Vivaldi – “The Four Seasons – Winter” – Vivaldi composed "The Four Seasons" in 1723. "Winter" is peppered with silvery pizzicato notes from the high strings, calling to mind icy rain. The ending line for the accompanying sonnet reads "this is winter, which nonetheless brings its own delights." The galaxies of the Virgo Supercluster will also bring us their own visual and intellectual delight.] Superclusters are among the largest structures in the known Universe. -
Integral Field Unit Spectroscopy of 10 Early Type Galactic Nuclei: I-Principal
Mon. Not. R. Astron. Soc. 000, 1–?? (2002) Printed 10 October 2018 (MN LaTEX style file v2.2) Integral field unit spectroscopy of 10 early type galactic nuclei: I - Principal component analysis Tomography and nuclear activity T.V. Ricci,1? J.E. Steiner,1 R.B. Menezes1 1Instituto de Astronomia, Geofísica e Ciências Atmosféricas, Universidade de São Paulo, 05508-900, São Paulo, Brazil Released 2002 Xxxxx XX ABSTRACT Most massive galaxies show emission lines that can be characterized as LINERs. To what extent this emission is related to AGNs or to stellar processes is still an open question. In this paper, we analysed a sample of such galaxies to study the central re- gion in terms of nuclear and circumnuclear emission lines, as well as the stellar compo- nent properties. For this reason, we selected 10 massive (σ >200 km s−1) nearby (d < 31 Mpc) galaxies and observed them with the IFU/GMOS (integral field unit/Gemini Multi-Object Spectrograph) spectrograph on the Gemini South Telescope. The data were analysed with principal component analysis (PCA) Tomography to assess the main properties of the objects. Two spectral regions were analysed: a yellow region (5100-5800 Å), adequate to show the properties of the stellar component, and a red region (6250-6800 Å), adequate to analyse the gaseous component. We found that all objects previously known to present emission lines have a central AGN-type emitting source. They also show gaseous and stellar kinematics typical of discs. Such discs may be co-aligned (NGC 1380 and ESO 208 G-21), in counter-rotation (IC 1459 and NGC 7097) or misaligned (IC 5181 and NGC 4546). -
ALABAMA University Libraries
THE UNIVERSITY OF ALABAMA University Libraries O VI In Elliptical Galaxies: Indicators of Cooling Flows Joel N. Bregman – University of Michigan Eric D. Miller – MIT Alex E. Athey – Carnegie Institution of Washington Jimmy A. Irwin – University of Michigan Deposited 09/13/2018 Citation of published version: Bregman, J., Miller, E., Athey, A., Irwin, J. (2005): O VI In Elliptical Galaxies: Indicators of Cooling Flows The Astrophysical Journal, 635(2). DOI: 10.1086/497421 © 2005. The American Astronomical Society. All rights reserved. Printed in U.S.A. The Astrophysical Journal, 635:1031–1043, 2005 December 20 # 2005. The American Astronomical Society. All rights reserved. Printed in U.S.A. O vi IN ELLIPTICAL GALAXIES: INDICATORS OF COOLING FLOWS Joel N. Bregman Department of Astronomy, University of Michigan, Ann Arbor, MI 48109; [email protected] Eric D. Miller Kavli Institute for Astrophysics and Space Science, MIT, Cambridge, MA 02139; [email protected] Alex E. Athey The Observatories, Carnegie Institution of Washington, Pasadena, CA 91101; [email protected] and Jimmy A. Irwin Department of Astronomy, University of Michigan, Ann Arbor, MI 48109; [email protected] Received 2005 April 25; accepted 2005 August 23 ABSTRACT Early-type galaxies often contain a hot X-ray–emitting interstellar medium [(3 8) ; 106 K] with an apparent radiative cooling time much less than a Hubble time. If unopposed by a heating mechanism, the gas will radiatively 4 À1 cool to temperatures P10 K at a rate proportional to LX /TX , typically 0.03–1 M yr . We can test whether gas is cooling through the 3 ; 105 K range by observing the O vi doublet, whose luminosity is proportional to the cooling rate. -
Distances from Stellar Kinematics for Peculiar Virgo Cluster Spiral Galaxies
Distances from Stellar Kinematics for Peculiar Virgo Cluster Spiral Galaxies Juan R. Cort´es Departamento de Astronom´ıa, Universidad de Chile Casilla 36-D, Santiago, Chile [email protected] National Astronomical Observatory of Japan 2-21-1 Osawa, Mitaka, Tokyo, 181-8588 Jeffrey D. P. Kenney Department of Astronomy, Yale University P.0. Box 208101, New Haven, CT 06520-8101 [email protected] Eduardo Hardy1 National Radio Astronomy Observatory Casilla El Golf 16-10, Las Condes, Santiago, Chile [email protected] Departamento de Astronom´ıa, Universidad de Chile2 Casilla 36-D, Santiago, Chile ABSTRACT We present distance estimates for eleven peculiar Virgo cluster spiral galaxies based on mea- surements of the stellar kinematics of their central 2 kpc. Stellar circular velocities were obtained using two-integral dynamical models. Distances were obtained by comparing, at each radius, the stellar circular velocities with synthetic Hα rotation curves derived from NIR Tully-Fisher relations. The results show that most of our galaxies are located within 4 Mpc of the core arXiv:0803.3638v2 [astro-ph] 14 Apr 2008 of the cluster. Three of these galaxies, previously classified as “low rotator galaxies” or with “Truncated/Compact” Hα radial distributions, have stellar kinematics-based distances that are discrepant with HI-based distances by at least 60%, and are likely to be located within the virial radius of the cluster. These discrepancies appear due to very truncated gas distributions plus non-circular gas motions or gas motions not in the plane of the stellar disk, perhaps as the result of gravitational interactions. Our results show that environmental effects can significantly re- duce the measured HI linewidths for some disturbed cluster galaxies, thus affecting the accurate determination of distances based on gas kinematics methods. -
Spitzer Observations of Environmental Effects on Virgo Cluster Galaxies
The Evolving ISM in the Milky Way & Nearby Galaxies Spitzer Observations of Environmental Effects on Virgo Cluster Galaxies Jeffrey D. P. Kenney1, O. Ivy Wong1, Anne Abramson1, Justin H. Howell2, Eric J. Murphy2 and George X. Helou2 1Astronomy Department, Yale University, P.O. Box 208101 New Haven, CT 06520-8101 2Spitzer Science Center, California Institute of Technology, Pasadena, CA 91125 [email protected] ABSTRACT We present initial results from SPITSOV, the Spitzer Survey of Virgo, which includes MIPS and IRAC observations for a carefully selected sample of 44 Virgo cluster spiral and peculiar galaxies. SPITSOV is part of a multiwavelength cam- paign to understand the effects of the cluster environment on galaxy evolution. These Virgo galaxies are different from galaxies outside of clusters, since most of them have been significantly modified by their environment. The SPITSOV data can serve the community as the Spitzer sample of nearby cluster spiral galaxies, a complement to the SINGS data for nearby non-cluster galaxies. In this paper we describe the sample, the goals of the study, and present pre- liminary results in 3 areas: 1. Evidence for ram pressure-induced disturbances in radio morphologies based on changes in the FIR-radio (70µm-20cm) correlation. 2. Evidence for ram-pressure stripped extraplanar gas tails from comparisons of dust/PAH (8µm) emission and optical dust extinction. 3. Evidence for unob- scured star-forming regions with large ratios of Hα to 24µm emission in some galaxies due to ram pressure stripping of dust. Subject headings: clusters: general | galaxy clusters: individual (Virgo) 1. Introduction Studies of galaxies near and far show broad evidence for the basic picture of hierarchical galaxy formation, in which large galaxies assemble from smaller pieces, and interactions { 2 { play a large role in evolution.