A Search for Ultraviolet Emission from Liners
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Kinematics of Planetary Nebulae in M51's Tidal Debris
Draft version December 17, 2018 A Preprint typeset using L TEX style emulateapj v. 14/09/00 KINEMATICS OF PLANETARY NEBULAE IN M51’S TIDAL DEBRIS Patrick R. Durrell [email protected] Department of Astronomy and Astrophysics, Penn State University, 525 Davey Lab, University Park, PA 16802 J. Christopher Mihos1, John J. Feldmeier [email protected], [email protected] Department of Astronomy, Case Western Reserve University, 10900 Euclid Ave, Cleveland, OH 44106 George H. Jacoby [email protected] WIYN Observatory2, P.O. Box 26732, Tucson AZ 85726 and Robin Ciardullo [email protected] Department of Astronomy and Astrophysics, Penn State University, 525 Davey Lab, University Park, PA 16802 accepted for publication in the Astrophysical Journal ABSTRACT We report the results of a radial velocity survey of planetary nebulae (PNe) located in the tidal features of the well-known interacting system NGC 5194/95 (M51). We find clear kinematic evidence that M51’s northwestern tidal debris consists of two discrete structures which overlap in projection – NGC 5195’s own tidal tail, and diffuse material stripped from NGC 5194. We compare these kinematic data to a new numerical simulation of the M51 system, and show that the data are consistent with the classic “single passage” model for the encounter, with a parabolic satellite trajectory and a 2:1 mass ratio. We also comment on the spectra of two unusual objects: a high-velocity PN which may be associated with NGC 5194’s halo, and a possible interloping high-redshift galaxy. Subject headings: galaxies: individual (M51) — galaxies: interactions — galaxies: kinematics and dynamics — planetary nebulae: general 1. -
FY08 Technical Papers by GSMTPO Staff
AURA/NOAO ANNUAL REPORT FY 2008 Submitted to the National Science Foundation July 23, 2008 Revised as Complete and Submitted December 23, 2008 NGC 660, ~13 Mpc from the Earth, is a peculiar, polar ring galaxy that resulted from two galaxies colliding. It consists of a nearly edge-on disk and a strongly warped outer disk. Image Credit: T.A. Rector/University of Alaska, Anchorage NATIONAL OPTICAL ASTRONOMY OBSERVATORY NOAO ANNUAL REPORT FY 2008 Submitted to the National Science Foundation December 23, 2008 TABLE OF CONTENTS EXECUTIVE SUMMARY ............................................................................................................................. 1 1 SCIENTIFIC ACTIVITIES AND FINDINGS ..................................................................................... 2 1.1 Cerro Tololo Inter-American Observatory...................................................................................... 2 The Once and Future Supernova η Carinae...................................................................................................... 2 A Stellar Merger and a Missing White Dwarf.................................................................................................. 3 Imaging the COSMOS...................................................................................................................................... 3 The Hubble Constant from a Gravitational Lens.............................................................................................. 4 A New Dwarf Nova in the Period Gap............................................................................................................ -
Infrared Spectroscopy of Nearby Radio Active Elliptical Galaxies
The Astrophysical Journal Supplement Series, 203:14 (11pp), 2012 November doi:10.1088/0067-0049/203/1/14 C 2012. The American Astronomical Society. All rights reserved. Printed in the U.S.A. INFRARED SPECTROSCOPY OF NEARBY RADIO ACTIVE ELLIPTICAL GALAXIES Jeremy Mould1,2,9, Tristan Reynolds3, Tony Readhead4, David Floyd5, Buell Jannuzi6, Garret Cotter7, Laura Ferrarese8, Keith Matthews4, David Atlee6, and Michael Brown5 1 Centre for Astrophysics and Supercomputing Swinburne University, Hawthorn, Vic 3122, Australia; [email protected] 2 ARC Centre of Excellence for All-sky Astrophysics (CAASTRO) 3 School of Physics, University of Melbourne, Melbourne, Vic 3100, Australia 4 Palomar Observatory, California Institute of Technology 249-17, Pasadena, CA 91125 5 School of Physics, Monash University, Clayton, Vic 3800, Australia 6 Steward Observatory, University of Arizona (formerly at NOAO), Tucson, AZ 85719 7 Department of Physics, University of Oxford, Denys, Oxford, Keble Road, OX13RH, UK 8 Herzberg Institute of Astrophysics Herzberg, Saanich Road, Victoria V8X4M6, Canada Received 2012 June 6; accepted 2012 September 26; published 2012 November 1 ABSTRACT In preparation for a study of their circumnuclear gas we have surveyed 60% of a complete sample of elliptical galaxies within 75 Mpc that are radio sources. Some 20% of our nuclear spectra have infrared emission lines, mostly Paschen lines, Brackett γ , and [Fe ii]. We consider the influence of radio power and black hole mass in relation to the spectra. Access to the spectra is provided here as a community resource. Key words: galaxies: elliptical and lenticular, cD – galaxies: nuclei – infrared: general – radio continuum: galaxies ∼ 1. INTRODUCTION 30% of the most massive galaxies are radio continuum sources (e.g., Fabbiano et al. -
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. -
Radio Continuum and CO Emission in Star-Forming Galaxies
A&A 385, 412–424 (2002) Astronomy DOI: 10.1051/0004-6361:20020140 & c ESO 2002 Astrophysics Radio continuum and CO emission in star-forming galaxies M. Murgia1,A.Crapsi1,2, L. Moscadelli3, and L. Gregorini1,4 1 Istituto di Radioastronomia del CNR, Via Gobetti 101, 40129, Bologna, Italy 2 Osservatorio Astrofisico di Arcetri, Largo E. Fermi 5, 50125, Firenze, Italy 3 Osservatorio Astronomico di Cagliari, Loc. Poggio dei Pini, Strada 54, 09012 Capoterra (CA), Italy 4 Dipartimento di Fisica, Universit`a di Bologna, Via B. Pichat 6/2, 40127 Bologna, Italy Received 30 October 2001 / Accepted 23 January 2002 Abstract. We combine the radio continuum images from the NRAO VLA Sky Survey with the CO-line observations from the extragalactic CO survey of the Five College Radio Astronomy Observatory to study the relationship between molecular gas and the star formation rate within the disks of 180 spiral galaxies at 4500 resolution. We find a tight correlation between these quantities. On average, the ratio between the radio continuum and the CO emission is constant, within a factor of 3, both inside the same galaxy and from galaxy to galaxy. The mean star formation efficiency deduced from the radio continuum corresponds to convert 3.5% of the available molecular gas into stars on a time scale of 108 yr and depends weakly on general galaxy properties, such as Hubble type or nuclear activity. A comparison is made with another similar analysis performed using the Hα luminosity as star formation indicator. The overall agreement we find between the two studies reinforces the use of the radio luminosity as star formation rate indicator not only on global but also on local scales. -
Core Radio and Optical Emission in Nearby FR I Radio Galaxies
Core Radio and Optical Emission in the Nuclei of Nearby FR I Radio Galaxies1 Gijs A. Verdoes Kleijn,2 Stefi A. Baum,3 P. Tim de Zeeuw,2 Christopher P. O’Dea3 ABSTRACT In this paper we analyze the relation between radio, optical continuum and Hα+[NII] emission from the cores of a sample of 21 nearby Fanaroff & Riley type I galaxies as observed with the VLBA and HST. The emission arises inside the inner tens of parsec of the galaxies. Core radio emission is observed in 19/20 galaxies, optical core continuum emission is detected in 12/21 galaxies and Hα+[NII] core emission is detected in 20/21 galaxies. We confirm the recently detected linear correlation between radio and optical core emission in FR I galaxies and show that both core emissions also correlate with central Hα+[NII] emission. The tight correlations between radio, optical and Hα+[NII] core emission constrain the bulk Lorentz factor to γ 2 5 and γ . 2 for a continuous ∼ − jet and a jet consisting of discrete blobs, respectively, assuming jet viewing angles in the range [30◦, 90◦]. Radio and optical core emissions are likely to be synchrotron radiation from the inner jet, possibly with a significant contribution from emission by an accretion disk and/or flow. Elliptical galaxies with LINER nuclei without large-scale radio jets seem to follow the core emission correlations found in FR I galaxies. This suggests that the central engines could be very similar for the two classes of AGNs. Subject headings: galaxies: active — galaxies: elliptical and lenticular, cD — galaxies: nuclei — galaxies: structure — ISM: dust, extinction. -
The Skyscraper 2009 04.Indd
A Better Galaxy Guide: Early Spring M67: One of the most ancient open clusters known and Craig Cortis is a great novelty in this regard. Located 1.7° due W of mag NGC 2419: 3.25° SE of mag 6.2 66 Aurigae. Hard to find 4.3 Alpha Cancri. and see; at E end of short row of two mag 7.5 stars. Highly NGC 2775: Located 3.7° ENE of mag 3.1 Zeta Hydrae. significant and worth the effort —may be approximately (Look for “Head of Hydra” first.) 300,000 light years distant and qualify as an extragalactic NGC 2903: Easily found at 1.5° due S of mag 4.3 Lambda cluster. Named the Intergalactic Wanderer. Leonis. NGC 2683: Marks NW “crook” of coathanger-type triangle M95: One of three bright galaxies forming a compact with easy double star mag 4.2 Iota Cancri (which is SSW by triangle, along with M96 and M105. All three can be seen 4.8°) and mag 3.1 Alpha Lyncis (at 6° to the ENE). together in a low power, wide field view. M105 is at the NE tip of triangle, midway between stars 52 and 53 Leonis, mag Object Type R.A. Dec. Mag. Size 5.5 and 5.3 respectively —M95 is at W tip. Lynx NGC 3521: Located 0.5° due E of mag 6.0 62 Leonis. M65: One of a pair of bright galaxies that can be seen in NGC 2419 GC 07h 38.1m +38° 53’ 10.3 4.2’ a wide field view along with M66, which lies just E. -
Stellar Population Gradient in Lenticular Galaxies: NGC 1023, NGC 3115 and NGC 4203
A&A 410, 803–812 (2003) Astronomy DOI: 10.1051/0004-6361:20031261 & c ESO 2003 Astrophysics Stellar population gradient in lenticular galaxies: NGC 1023, NGC 3115 and NGC 4203 M. Bassin1 and Ch. Bonatto1 Universidade Federal do Rio Grande do Sul, Instituto de F´ısica, CP 15051, Porto Alegre CEP 91501-970, RS, Brazil Received 11 March 2003 / Accepted 2 July 2003 Abstract. We investigate the stellar population content in the lenticular galaxies NGC 1023, NGC 3115 and NGC 4203 applying a population synthesis method based on a seven component spectral basis with different ages – 2.5 106,10 106,25 106,75 106, 200 106,1.2 109 and older than 1010 years, and metallicity in the range 1.3 ×[Z/Z ] × 0.2. This× study employs× two-dimensional× × STIS spectra in the range λλ2900–5700 Å, obtained from the Hubble− ≤ Space Telescope ≤− public archives. We extracted one-dimensional spectra in adjacent windows 100 pc wide (projected distance) from the nuclear regions up to 300–400 pc. The largest contribution, both in λ5870 Å flux and mass fraction, comes from old stars (age > 1010 years). We verified the possible existence of circumnuclear bursts (CNBs) in NGC 3115 and NGC 4203. Key words. galaxies: elliptical and lenticular, cD – galaxies: stellar content – galaxies: nuclei 1. Introduction the purpose of determining the star formation history in galax- ies based on integrated properties. A precise determination of properties of the stellar content of Two main approaches have been considered: evolutionary galaxies is clearly an important issue, since they are related synthesis, a technique to study the spectrophotometric evolu- to the galaxy formation and evolution. -
Astronomy Magazine Special Issue
γ ι ζ γ δ α κ β κ ε γ β ρ ε ζ υ α φ ψ ω χ α π χ φ γ ω ο ι δ κ α ξ υ λ τ μ β α σ θ ε β σ δ γ ψ λ ω σ η ν θ Aι must-have for all stargazers η δ μ NEW EDITION! ζ λ β ε η κ NGC 6664 NGC 6539 ε τ μ NGC 6712 α υ δ ζ M26 ν NGC 6649 ψ Struve 2325 ζ ξ ATLAS χ α NGC 6604 ξ ο ν ν SCUTUM M16 of the γ SERP β NGC 6605 γ V450 ξ η υ η NGC 6645 M17 φ θ M18 ζ ρ ρ1 π Barnard 92 ο χ σ M25 M24 STARS M23 ν β κ All-in-one introduction ALL NEW MAPS WITH: to the night sky 42,000 more stars (87,000 plotted down to magnitude 8.5) AND 150+ more deep-sky objects (more than 1,200 total) The Eagle Nebula (M16) combines a dark nebula and a star cluster. In 100+ this intense region of star formation, “pillars” form at the boundaries spectacular between hot and cold gas. You’ll find this object on Map 14, a celestial portion of which lies above. photos PLUS: How to observe star clusters, nebulae, and galaxies AS2-CV0610.indd 1 6/10/10 4:17 PM NEW EDITION! AtlAs Tour the night sky of the The staff of Astronomy magazine decided to This atlas presents produce its first star atlas in 2006. -
The Hot, Warm and Cold Gas in Arp 227 - an Evolving Poor Group R
The hot, warm and cold gas in Arp 227 - an evolving poor group R. Rampazzo, P. Alexander, C. Carignan, M.S. Clemens, H. Cullen, O. Garrido, M. Marcelin, K. Sheth, G. Trinchieri To cite this version: R. Rampazzo, P. Alexander, C. Carignan, M.S. Clemens, H. Cullen, et al.. The hot, warm and cold gas in Arp 227 - an evolving poor group. Monthly Notices of the Royal Astronomical Society, Oxford University Press (OUP): Policy P - Oxford Open Option A, 2006, 368, pp.851. 10.1111/j.1365- 2966.2006.10179.x. hal-00083833 HAL Id: hal-00083833 https://hal.archives-ouvertes.fr/hal-00083833 Submitted on 13 Dec 2020 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Mon. Not. R. Astron. Soc. 368, 851–863 (2006) doi:10.1111/j.1365-2966.2006.10179.x The hot, warm and cold gas in Arp 227 – an evolving poor group R. Rampazzo,1 P. Alexander,2 C. Carignan,3 M. S. Clemens,1 H. Cullen,2 O. Garrido,4 M. Marcelin,5 K. Sheth6 and G. Trinchieri7 1Osservatorio Astronomico di Padova, Vicolo dell’Osservatorio 5, I-35122 Padova, Italy 2Astrophysics Group, Cavendish Laboratories, Cambridge CB3 OH3 3Departement´ de physique, Universite´ de Montreal,´ C. -
Hubble Sights Galaxy Stuck in the Middle 30 April 2018
Hubble sights galaxy stuck in the middle 30 April 2018 from Earth in the constellation of Camelopardalis (the Giraffe). Camelopardalis contains many other interesting deep-sky objects, including the open cluster NGC 1502, the elegant Kemble's Cascade asterism, and the starburst galaxy NGC 2146. Provided by NASA Credit: ESA/Hubble & NASA, A. Fillipenko This pretty, cloud-like object may not look much like a galaxy—it lacks the well-defined arms of a spiral galaxy, or the reddish bulge of an elliptical—but it is in fact something known as a lenticular galaxy. Lenticular galaxies sit somewhere between the spiral and elliptical types; they are disk-shaped, like spirals, but they no longer form large numbers of new stars and thus contain only aging populations of stars, like ellipticals. NGC 2655's core is extremely luminous, resulting in its additional classification as a Seyfert galaxy: a type of active galaxy with strong and characteristic emission lines. This luminosity is thought to be produced as matter is dragged onto the accretion disk of a supermassive black hole sitting at the center of NGC 2655. The structure of NGC 2655's outer disk, on the other hand, appears calmer, but it is oddly shaped. The complex dynamics of the gas in the galaxy suggest that it may have had a turbulent past, including mergers and interactions with other galaxies. NGC 2655 is located about 80 million light-years 1 / 2 APA citation: Hubble sights galaxy stuck in the middle (2018, April 30) retrieved 28 September 2021 from https://phys.org/news/2018-04-hubble-sights-galaxy-stuck-middle.html This document is subject to copyright. -
Do Normal Galaxies Host a Black Hole? the High Energy Perspective
DO NORMAL GALAXIES HOST A BLACK HOLE? THE HIGH ENERGY PERSPECTIVE 1 Y. Terashima2 Nagoya University ABSTRACT We review ASCA results on a search for low luminosity active nuclei at the center of nearby normal galaxies. More than a dozen low-luminosity AGN have been discovered with 2–10 keV − − luminosity in the range 1040 41 ergs s 1. Their X-ray properties are in some respects similar to those of luminous Seyfert galaxies, but differ in other respects. We also present estimated black hole masses in low luminosity AGNs and a drastic activity decline in the nucleus of the radio galaxy Fornax A. These results altogether suggest that relics of the past luminous AGNs lurk in nearby normal galaxies. KEYWORDS: Galaxies; Low luminosity AGNs; LINERs; Black holes 1. Introduction The number density of quasars is peaked at a redshift of z ∼ 2 and rapidly de- creases toward smaller redshifts. In the local universe, there is no AGN emitting at huge luminosity like quasars. These facts infer that quasars evolve to supermassive black holes in nearby apparently normal galaxies (e.g. Rees 1990). The growing evidence for supermassive black holes in nearby galaxies are ob- tained from recent optical and radio observations of gas/stellar kinematics around the center of galaxies (e.g. Ho 1998a; Magorrian et al. 1998; Kormendy & Rich- stone 1995). If fueling to the supermassive black hole takes place with a small arXiv:astro-ph/9905218v1 17 May 1999 mass accretion rate, they are expected to be observed as very low luminosity AGNs compared to quasars. Recent optical spectroscopic surveys have shown that low level activity is fairly common in nearby galaxies.