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Pdf, Integral-Field Stellar and Ionized Gas Kinematics of Peculiar Virgo
The Astrophysical Journal Supplement Series, 216:9 (34pp), 2015 January doi:10.1088/0067-0049/216/1/9 C 2015. The American Astronomical Society. All rights reserved. INTEGRAL-FIELD STELLAR AND IONIZED GAS KINEMATICS OF PECULIAR VIRGO CLUSTER SPIRAL GALAXIES Juan R. Cortes´ 1,2,3,5, Jeffrey D. P. Kenney4, and Eduardo Hardy1,3,5,6 1 National Radio Astronomy Observatory Avenida Nueva Costanera 4091, Vitacura, Santiago, Chile; [email protected], [email protected] 2 Joint ALMA Observatory Alonso de Cordova´ 3107, Vitacura, Santiago, Chile 3 Departamento de Astronom´ıa, Universidad de Chile Casilla 36-D, Santiago, Chile 4 Department of Astronomy, Yale University, P.O. Box 208101, New Haven, CT 06520-8101, USA; [email protected] Received 2014 March 10; accepted 2014 November 7; published 2014 December 24 ABSTRACT We present the stellar and ionized gas kinematics of 13 bright peculiar Virgo cluster galaxies observed with the DensePak Integral Field Unit at the WIYN 3.5 m telescope in order to look for kinematic evidence that these galaxies have experienced gravitational interactions or gas stripping. Two-dimensional maps of the stellar velocity V, stellar velocity dispersion σ, and the ionized gas velocity (Hβ and/or [O iii]) are presented for the galaxies in the sample. The stellar rotation curves and velocity dispersion profiles are determined for 13 galaxies, and the ionized gas rotation curves are determined for 6 galaxies. Misalignments between the optical and kinematical major axes are found in several galaxies. While in some cases this is due to a bar, in other cases it seems to be associated with gravitational interaction or ongoing ram pressure stripping. -
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. -
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. -
The Recent and Continuing Assembly of Field Ellipticals by Red Mergers Pieter G
ACCEPTED FOR PUBLICATION IN THE ASTRONOMICAL JOURNAL (DECEMBER 2005 ISSUE) Preprint typeset using LATEX style emulateapj v. 11/12/01 THE RECENT AND CONTINUING ASSEMBLY OF FIELD ELLIPTICALS BY RED MERGERS PIETER G. VAN DOKKUM Department of Astronomy, Yale University, New Haven, CT 06520-8101; [email protected] Accepted for publication in the Astronomical Journal (December 2005 issue) ABSTRACT We present a study of tidal debris associated with 126 nearby red galaxies, selected from the 1.2 degree2 Multiwavelength Survey by Yale-Chile (MUSYC) and the 9.3 degree2 NOAO Deep Wide-Field Survey. In the full sample 67 galaxies (53 %) show morphological signatures of tidal interactions, consisting of broad fans of stars, tails, and other asymmetries at very faint surface brightness levels. When restricting the sample to the 86 bulge-dominated early-type galaxies the fraction of tidally disturbed galaxies rises to 71 %, which implies that for every “normal” undisturbed elliptical there are two which show clear signs of interactions. The tidal features are red and smooth, and often extend over 50 kpc. Of the tidally distorted galaxies about 2 ¡ 3 are remnants and 1 ¡ 3 are interacting with a companion galaxy. The companions are usually bright red galaxies as well: the median R-band luminosity ratio of the tidal pairs is 0.31, and the median color difference after correcting for the slope £ ¢ of the color-magnitude relation is ¢ 0 02 in B R. If the ongoing mergers are representative for the progenitors of the remnants ¤ 35 % of bulge-dominated galaxies experienced a merger with mass ratio 1 : 4 in the recent past. -
Download Date 30/09/2021 18:12:24
GALAXY ANGULAR MOMENTUM Item Type text; Dissertation-Reproduction (electronic) Authors Thompson, Laird Alan, 1947- Publisher The University of Arizona. Rights Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author. Download date 30/09/2021 18:12:24 Link to Item http://hdl.handle.net/10150/288356 INFORMATION TO USERS This material was produced from a microfilm copy of the original document. While ihs most advanced technological means to photograph and reproduce this document have been used, the quality is heavily dependent upon the quality of the original submitted. The following explanation of techniques is provided to help you understand markings or patterns which may appear on this reproduction. t 1.The sign or "target" for pages apparently lacking from the document photographed is "Missing Page(s)". If it was possible to obtain the missing page(s) or section, they are spliced into the film along with adjacent pages. This may have necessitated cutting thru an image and duplicating adjacent pages to insure you complete continuity. 2. When an image on the film is obliterated with a large round black mark, it is an indication that the photographer suspected that the copy may have moved during exposure and thus cause a blurred image. You will find a good image of the page in the adjacent frame. 3. When a map, drawing or chart, etc., was part of the material being photographed the photographer followed a definite method in "sectioning" the material. -
Properties of Simulated Milky Way-Mass Galaxies in Loose Group and field Environments
A&A 547, A63 (2012) Astronomy DOI: 10.1051/0004-6361/201219649 & c ESO 2012 Astrophysics Properties of simulated Milky Way-mass galaxies in loose group and field environments C. G. Few1,B.K.Gibson1,2,3,S.Courty4, L. Michel-Dansac4,C.B.Brook5, and G. S. Stinson6 1 Jeremiah Horrocks Institute, University of Central Lancashire, Preston, PR1 2HE, UK e-mail: [email protected] 2 Department of Astronomy & Physics, Saint Mary’s University, Halifax, Nova Scotia, B3H 3C3, Canada 3 Monash Centre for Astrophysics, Monash University, 3800 Victoria, Australia 4 Université de Lyon, Université Lyon 1, Observatoire de Lyon, CNRS, UMR 5574, Centre de Recherche Astrophysique de Lyon, École Normale Supérieure de Lyon, 9 avenue Charles André, 69230 Saint-Genis Laval, France 5 Grupo de Astrofísica, Departamento de Fisica Teorica, Modulo C-15, Universidad Autónoma de Madrid, 28049 Cantoblanco, Spain 6 Max-Planck-Institut für Astronomie, Königstuhl 17, 69117 Heidelberg, Germany Received 22 May 2012 / Accepted 27 September 2012 ABSTRACT Aims. We test the validity of comparing simulated field disk galaxies with the empirical properties of systems situated within envi- ronments more comparable to loose groups, including the Milky Way’s Local Group. Methods. Cosmological simulations of Milky Way-mass galaxies have been realised in two different environment samples: in the field and in loose groups environments with similar properties to the Local Group. Apart from the differing environments of the galaxies, the samples are kept as homogeneous as possible with equivalent ranges in last major merger time, halo mass and halo spin. Comparison of these two samples allow for systematic differences in the simulations to be identified. -
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. -
New Lessons from the HI Size-Mass Relation of Galaxies 3
Mon. Not. R. Astron. Soc. 000, 000–000 (2014) Printed 6 May 2016 (MN LATEX style file v2.2) New Lessons from the HI Size-Mass Relation of Galaxies Jing Wang1⋆, B¨arbel S. Koribalski1, Paolo Serra1, Thijs van der Hulst2, Sambit Roychowdhury3, Peter Kamphuis1,4, Jayaram N. Chengalur4 1Australia Telescope National Facility, CSIRO Astronomy and Space Science, PO Box 76, Epping, NSW 1710, Australia 2University of Groningen, Kapteyn Astronomical Institute, Landleven 12, 9747 AD, Groningen, The Netherlands 3Max-Planck Institut f¨ur Astrophysik, D-85748 Garching, Germany 4National Centre for Radio Astrophysics, TIFR, Ganeshkhind, Pune 411007, India Accepted 2014 ???? ?? Received 2014 ???? ??; in original form 2014 January ABSTRACT We revisit the Hi size-mass (DHI-MHI) relation of galaxies with a sample of more than 500 nearby galaxies covering over five orders of magnitude in Hi mass and more than ten B-band magnitudes. The relation is remarkably tight with a scatter σ ∼0.06 dex, or 14%. The scatter does not change as a function of galaxy luminosity, Hi richness or morphological type. The relation is linked to the fact that dwarf and spiral galaxies have a homogenous radial profile of Hi surface density in the outer regions when the radius is normalised by DHI. The early-type disk galaxies typically have shallower Hi radial profiles, indicating a different gas accretion history. We argue that the process of atomic-to-molecular gas conversion or star formation cannot explain the tightness of the DHI-MHI relation. This simple relation puts strong constraints on simulation models for galaxy formation. Key words: intergalactic medium; galaxies 1 INTRODUCTION samples: Verheijen & Sancisi. -
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 -
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. -
The Norris Survey of the Corona Borealis Supercluster: II. Galaxy
The Norris Survey of the Corona Borealis Supercluster: II. Galaxy Evolution with Redshift and Environment Todd A. Small1 and Wallace L.W. Sargent Palomar Observatory, California Institute of Technology, Pasadena, CA 91125 Electronic mail: [email protected], [email protected] Donald Hamilton Max-Planck-Institut f¨ur Astronomie, K¨onigstuhl 17, Heidelberg D-69117, Germany Electronic mail: [email protected] ABSTRACT We measure the field galaxy luminosity function (LF) as a function of color and redshift from z =0 to z =0.5 using galaxies from the Norris Survey of the Corona Borealis Supercluster. The data set consists of 603 field galaxies with m m 0 < z ≤ 0.5 and spans a wide range in apparent magnitude (14.0 ∼<r ∼< 21.5 ), although our field galaxy LF analysis is limited to 493 galaxies with r ≤ 20.0m. We use the observed g − r colors of the galaxies to compute accurate corrections to the rest BAB and r bands. We find that our local r-band LF, when normalized to counts in high galactic latitude fields, agrees well with the local LF measured in the Las Campanas Redshift Survey. Our BAB-band local LF, however, does not match the bj-band LF from the Stromlo/APM survey, having a normalization 1.6 times higher. We see compelling evidence that the BAB-band field galaxy LF evolves with redshift. The evolution is strongest for arXiv:astro-ph/9705021v1 5 May 1997 the population of star-forming galaxies with [O II] λ3727 rest-frame equivalent widths greater than 10A.˚ The population of red, quiescent galaxies shows no sign of evolution to z = 0.5. -
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.