Made-To-Measure Particle Models of Intermediate-Luminosity Elliptical Galaxies: Regularization, Parameter Estimation, and the Dark Halo of NGC 4494
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Radio Astronom1y G
£t,: ,/ NATIONAL RADIO ASTRONOMY OBSERVATORY QUARTERLY REPORT October 1 - December 31, 1989 RADIO ASTRONOM1Y G.. '8 tO- C~oe'' n,'evI! I E. Vi. t-Li 1 2 1990 TABLE OF CONTENTS A. TELESCOPE USAGE ... .... ...... ............ 1 B. 140-FOOT OBSERVING PROGRAMS . .... .......... ... 1 C. 12-METER TELESCOPE ....... ..... ., .... ........ 5 D. VERY LARGE ARRAY ....... 1...................8 E. SCIENTIFIC HIGHLIGHTS .... ........ 19 F. PUBLICATIONS ............. G. CENTRAL DEVELOPMENT LABORATORY ........ 20 H. GREEN BANK ELECTRONICS . .. .a.. ...... 21 I. 12-METER ELECTRONICS ...... .. 0. I. 22 J. VLA ELECTRONICS ...... 0..... ..... .... a. 24 K. AIPS .... .............. ...... ............. 26 L. VLA COMPUTER ............. .. .0. .0. ... 27 M. VERY LONG BASELINE ARRAY . .. .0 .0 .0 .0 .0 . .0 .. 27 N. PERSONNEL .. ...... .... .0.0 . .0. .0. .. e. 30 APPENDIX A: List of NRAO Preprints A. TELESCOPE USAGE The NRAO telescopes have been scheduled for research and maintenance in the following manner during the fourth quarter of 1989. 140-ft 12-m VLA Scheduled observing (hrs) 1901.75 1583.50 1565.2 Scheduled maintenance and equipment changes 132.00 107.75 259.8 Scheduled tests and calibrations 20.75 425.75 327.1 Time lost 139.25 208.25 107.0 Actual observing 1762.50 1375.25 1458.2 B. 140-FOOT OBSERVING PROGRAMS The following line programs were conducted during this quarter. No. Observer(s) Program A-95 Avery, L (Herzberg) Observations at 18.2, 18.6, and Bell, M. (Herzberg) 23.7 GHz of cyanopolyynes in carbon Feldman, P. (Herzberg) stars part II. MacLeod, J. (Herzberg) Matthews, H. (Herzberg) B-493 Bania, T. (Boston) Measurements at 8.666 GHz of 3He + Rood, R. (Virginia) emission in HII regions and planetary Wilson, T. -
Kinetic Effects on Turbulence Driven by the Magnetorotational Instability
Kinetic Effects on Turbulence Driven by the Magnetorotational Instability in Black Hole Accretion Prateek Sharma A Dissertation Presented to the Faculty of Princeton University in Candidacy for the Degree of Doctor of Philosophy arXiv:astro-ph/0703542v1 20 Mar 2007 Recommended for Acceptance by the department of Astrophysical sciences September 2006 c Copyright by Prateek Sharma, 2018. All Rights Reserved Abstract Many astrophysical objects (e.g., spiral galaxies, the solar system, Saturn’s rings, and luminous disks around compact objects) occur in the form of a disk. One of the important astrophysical problems is to understand how rotationally supported disks lose angular momentum, and accrete towards the bottom of the gravitational potential, converting gravitational energy into thermal (and radiation) energy. The magnetorotational instability (MRI), an instability causing turbulent trans- port in ionized accretion disks, is studied in the kinetic regime. Kinetic effects are important because radiatively inefficient accretion flows (RIAFs), like the one around the supermassive black hole in the center of our Galaxy, are collisionless. The ion Larmor radius is tiny compared to the scale of MHD turbulence so that the drift kinetic equation (DKE), obtained by averaging the Vlasov equation over the fast gy- romotion, is appropriate for evolving the distribution function. The kinetic MHD formalism, based on the moments of the DKE, is used for linear and nonlinear stud- ies. A Landau fluid closure for parallel heat flux, which models kinetic effects like collisionless damping, is used to close the moment hierarchy. We show that the kinetic MHD and drift kinetic formalisms give the same set of linear modes for a Keplerian disk. -
Overview on Spectral Line Source Finding and Visualisation
CSIRO PUBLISHING Publications of the Astronomical Society of Australia, 2012, 29, 359–370 http://dx.doi.org/10.1071/AS12030 Overview on Spectral Line Source Finding and Visualisation B. S. Koribalski CSIRO Astronomy & Space Science, Australia Telescope National Facility, PO Box 76, Epping, NSW 1710, Australia Email: [email protected] Abstract: Here I will outline successes and challenges for finding spectral line sources in large data cubes that are dominated by noise. This is a 3D challenge as the sources we wish to catalog are spread over several spatial pixels and spectral channels. While 2D searches can be applied, e.g. channel by channel, optimal searches take into account the 3-dimensional nature of the sources. In this overview I will focus on HI 21-cm spectral line source detection in extragalactic surveys, in particular HIPASS, the HI Parkes All-Sky Survey and WALLABY, the ASKAP HI All-Sky Survey. I use the original HIPASS data to highlight the diversity of spectral signatures of galaxies and gaseous clouds, both in emission and absorption. Among others, I report the À1 discovery of a 680 km s wide HI absorption trough in the megamaser galaxy NGC 5793. Issues such as source confusion and baseline ripples, typically encountered in single-dish HI surveys, are much reduced in interferometric HI surveys. Several large HI emission and absorption surveys are planned for the Australian Square Kilometre Array Pathfinder (ASKAP): here we focus on WALLABY, the 21-cm survey of the sky (d , þ308; z , 0.26) which will take about one year of observing time with ASKAP. -
Atlas Menor Was Objects to Slowly Change Over Time
C h a r t Atlas Charts s O b by j Objects e c t Constellation s Objects by Number 64 Objects by Type 71 Objects by Name 76 Messier Objects 78 Caldwell Objects 81 Orion & Stars by Name 84 Lepus, circa , Brightest Stars 86 1720 , Closest Stars 87 Mythology 88 Bimonthly Sky Charts 92 Meteor Showers 105 Sun, Moon and Planets 106 Observing Considerations 113 Expanded Glossary 115 Th e 88 Constellations, plus 126 Chart Reference BACK PAGE Introduction he night sky was charted by western civilization a few thou - N 1,370 deep sky objects and 360 double stars (two stars—one sands years ago to bring order to the random splatter of stars, often orbits the other) plotted with observing information for T and in the hopes, as a piece of the puzzle, to help “understand” every object. the forces of nature. The stars and their constellations were imbued with N Inclusion of many “famous” celestial objects, even though the beliefs of those times, which have become mythology. they are beyond the reach of a 6 to 8-inch diameter telescope. The oldest known celestial atlas is in the book, Almagest , by N Expanded glossary to define and/or explain terms and Claudius Ptolemy, a Greco-Egyptian with Roman citizenship who lived concepts. in Alexandria from 90 to 160 AD. The Almagest is the earliest surviving astronomical treatise—a 600-page tome. The star charts are in tabular N Black stars on a white background, a preferred format for star form, by constellation, and the locations of the stars are described by charts. -
Resolving the AGN and Host Emission in the Mid-Infrared Using A
Draft version February 23, 2015 Preprint typeset using LATEX style emulateapj v. 5/2/11 RESOLVING THE AGN AND HOST EMISSION IN THE MID-INFRARED USING A MODEL-INDEPENDENT SPECTRAL DECOMPOSITION Antonio Hernan´ -Caballero,1 Almudena Alonso-Herrero,1 Evanthia Hatziminaoglou,2 Henrik W. W. Spoon,3 Cristina Ramos Almeida,4,5 Tanio D´ıaz Santos,6,7 Sebastian F. H¨onig,8 Omaira Gonzalez´ -Mart´ın,9 and Pilar Esquej10 Draft version February 23, 2015 ABSTRACT We present results on the spectral decomposition of 118 Spitzer Infrared Spectrograph (IRS) spectra from local active galactic nuclei (AGN) using a large set of Spitzer/IRS spectra as templates. The templates are themselves IRS spectra from extreme cases where a single physical component (stellar, interstellar, or AGN) completely dominates the integrated mid-infrared emission. We show that a linear combination of one template for each physical component reproduces the observed IRS spectra of AGN hosts with unprecedented fidelity for a template fitting method, with no need to model extinction separately. We use full probability distribu- tion functions to estimate expectation values and uncertainties for observables, and find that the decomposition results are robust against degeneracies. Furthermore, we compare the AGN spectra derived from the spec- tral decomposition with sub-arcsecond resolution nuclear photometry and spectroscopy from ground-based observations. We find that the AGN component derived from the decomposition closely matches the nuclear spectrum, with a 1-σ dispersion of 0.12 dex in luminosity and typical uncertainties of ∼0.19 in the spectral index and ∼0.1 in the silicate strength. -
Extended H I Disks in Dust–Lane Elliptical Galaxies1
View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by CERN Document Server Extended H I disks in dust{lane elliptical galaxies1 Thomas A. Oosterloo ASTRON, PO Box 2, 7990 AA, Dwingeloo, The Netherlands Raffaella Morganti ASTRON, PO Box 2, 7990 AA, Dwingeloo, The Netherlands Elaine M. Sadler School of Physics, University of Sydney, NSW 2006, Australia Daniela Vergani Dipartimento di Astronomia, Universit`a di Bologna, via Zamboni 33, I-40126 Bologna, Italy Nelson Caldwell Smithsonian Institution, Steward Observatory, 949 N Cherry Avenue, Tucson Arizona 85719, USA ABSTRACT –2– We present the results of H I observations of five dust-lane ellipticals with the Aus- tralia Telescope Compact Array. Two galaxies (NGC 3108 and NGC 1947) are detected, and sensitive upper limits are obtained for the other three. In the two detected galaxies, the H I is distributed in a regular, extended and warped disk-like structure of low surface brightness. Adding data from the literature, we find that several more dust-lane ellipti- cals have regular H I structures. This H I is likely to be a remnant of accretions/mergers which took place a considerable time ago, and in which a significant fraction of the gas survived to form a disk. The presence of regular H I structures suggests that some mergers lead to galaxies with extended low surface brightness density gas disks. These gas disk will evolve very slowly and these elliptical galaxies will remain gas rich for a long period of time. One of the galaxies we observed (NGC 3108) has a very large amount of neutral 9 hydrogen (MHI =4:5 10 M ; MHI=LB 0:09), which is very regularly distributed × ∼ in an annulus extending to a radius of 6 Reff . -
Multi-Species Measurements of the Firehose and Mirror Instability Thresholds in the Solar Wind C
The Astrophysical Journal Letters, 825:L26 (5pp), 2016 July 10 doi:10.3847/2041-8205/825/2/L26 © 2016. The American Astronomical Society. All rights reserved. MULTI-SPECIES MEASUREMENTS OF THE FIREHOSE AND MIRROR INSTABILITY THRESHOLDS IN THE SOLAR WIND C. H. K. Chen1,2, L. Matteini1, A. A. Schekochihin3,4, M. L. Stevens5, C. S. Salem2, B. A. Maruca2, M. W. Kunz6, and S. D. Bale2,7 1 Department of Physics, Imperial College London, London SW7 2AZ, UK; [email protected] 2 Space Sciences Laboratory, University of California, Berkeley, CA 94720, USA 3 Rudolf Peierls Centre for Theoretical Physics, University of Oxford, Oxford OX1 3NP, UK 4 Merton College, Oxford OX1 4JD, UK 5 Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138, USA 6 Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544, USA 7 Department of Physics, University of California, Berkeley, CA 94720, USA Received 2016 April 11; revised 2016 June 8; accepted 2016 June 8; published 2016 July 8 ABSTRACT The firehose and mirror instabilities are thought to arise in a variety of space and astrophysical plasmas, constraining the pressure anisotropies and drifts between particle species. The plasma stability depends on all species simultaneously, meaning that a combined analysis is required. Here, we present the first such analysis in the solar wind, using the long-wavelength stability parameters to combine the anisotropies and drifts of all major species (core and beam protons, alphas, and electrons). At the threshold, the firehose parameter was found to be dominated by protons (67%), but also to have significant contributions from electrons (18%) and alphas (15%). -
190 Index of Names
Index of names Ancora Leonis 389 NGC 3664, Arp 005 Andriscus Centauri 879 IC 3290 Anemodes Ceti 85 NGC 0864 Name CMG Identification Angelica Canum Venaticorum 659 NGC 5377 Accola Leonis 367 NGC 3489 Angulatus Ursae Majoris 247 NGC 2654 Acer Leonis 411 NGC 3832 Angulosus Virginis 450 NGC 4123, Mrk 1466 Acritobrachius Camelopardalis 833 IC 0356, Arp 213 Angusticlavia Ceti 102 NGC 1032 Actenista Apodis 891 IC 4633 Anomalus Piscis 804 NGC 7603, Arp 092, Mrk 0530 Actuosus Arietis 95 NGC 0972 Ansatus Antliae 303 NGC 3084 Aculeatus Canum Venaticorum 460 NGC 4183 Antarctica Mensae 865 IC 2051 Aculeus Piscium 9 NGC 0100 Antenna Australis Corvi 437 NGC 4039, Caldwell 61, Antennae, Arp 244 Acutifolium Canum Venaticorum 650 NGC 5297 Antenna Borealis Corvi 436 NGC 4038, Caldwell 60, Antennae, Arp 244 Adelus Ursae Majoris 668 NGC 5473 Anthemodes Cassiopeiae 34 NGC 0278 Adversus Comae Berenices 484 NGC 4298 Anticampe Centauri 550 NGC 4622 Aeluropus Lyncis 231 NGC 2445, Arp 143 Antirrhopus Virginis 532 NGC 4550 Aeola Canum Venaticorum 469 NGC 4220 Anulifera Carinae 226 NGC 2381 Aequanimus Draconis 705 NGC 5905 Anulus Grahamianus Volantis 955 ESO 034-IG011, AM0644-741, Graham's Ring Aequilibrata Eridani 122 NGC 1172 Aphenges Virginis 654 NGC 5334, IC 4338 Affinis Canum Venaticorum 449 NGC 4111 Apostrophus Fornac 159 NGC 1406 Agiton Aquarii 812 NGC 7721 Aquilops Gruis 911 IC 5267 Aglaea Comae Berenices 489 NGC 4314 Araneosus Camelopardalis 223 NGC 2336 Agrius Virginis 975 MCG -01-30-033, Arp 248, Wild's Triplet Aratrum Leonis 323 NGC 3239, Arp 263 Ahenea -
Super-Massive Black Hole Scaling Relations and Peculiar Ringed Galaxies
SUPER-MASSIVE BLACK HOLE SCALING RELATIONS AND PECULIAR RINGED GALAXIES A DISSERTATION SUBMITTED TO THE FACULTY OF THE GRADUATE SCHOOL OF THE UNIVERSITY OF MINNESOTA BY BURCIN MUTLU IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY MARC S. SEIGAR June, 2017 c BURCIN MUTLU 2017 ALL RIGHTS RESERVED Acknowledgements There are several people who I would like to acknowledge for directly or indirectly contributing to this dissertation. First and foremost, I would like to acknowledge the guidance and support of my ad- visor, Marc S. Seigar. I am thankful to him for his continuous encouragement, patience, and kindness. I appreciate all his contributions of knowledge, expertise, and time, which were invaluable to my success in graduate school. He has set an example of excellence as a researcher, mentor, and role model. In addition, I would like to thank my dissertation committee, Liliya L. R. Williams, M. Claudia Scarlata, and Robert Lysak, for their insightful input, constructive criticism and direction during the course of this dissertation. I have crossed paths with many collaborators who have influenced and enhanced my research. Patrick Treuthardt has been a collaborator for most of the work during my dissertation. The addition of his scientific point of view has improved the quality of the work in this dissertation tremendously. Our discussions have always been stimulating and rewarding. I am thankful to him for mentoring me and being a dear friend to me. I would also like to thank Benjamin L. Davis for numerous helpful advice and inspiring discussions. He has directly involved with many aspects of Chapter 1. -
The Carnegie-Irvine Galaxy Survey. Iii. the Three-Component Structure of Nearby Elliptical Galaxies
DRAFT VERSION 6 Preprint typeset using LATEX style emulateapj v. 26/01/00 THE CARNEGIE-IRVINE GALAXY SURVEY. III. THE THREE-COMPONENT STRUCTURE OF NEARBY ELLIPTICAL GALAXIES 1 2 3 2 4 5 6 SONG HUANG (黄崧) , , LUIS C. HO , CHIEN Y. PENG ,ZHAO-YU LI (李兆聿) , AND AARON J. BARTH Draft version 6 ABSTRACT Motivated by recent developments in our understanding of the formation and evolution of massive galaxies, we explore the detailed photometric structure of a representative sample of 94 bright, nearby elliptical galaxies, using high-quality optical images from the Carnegie-Irvine Galaxy Survey. The sample spans a range of environ- 10.2 12.0 ments and stellar masses, from M∗ = 10 to 10 M⊙. We exploit the unique capabilities of two-dimensional image decomposition to explore the possibility that local elliptical galaxies may contain photometrically distinct substructure that can shed light on their evolutionary history. Compared with the traditional one-dimensional ap- proach, these two-dimensional models are capable of consistently recovering the surface brightness distribution and the systematic radial variation of geometric informationat the same time. Contrary to conventionalperception, we find that the global light distribution of the majority (>75%) of elliptical galaxies is not well described by a single Sérsic function. Instead, we propose that local elliptical∼ galaxies generically contain three subcomponents: a compact (Re <1 kpc) inner component with luminosity fraction f 0.1 − 0.15; an intermediate-scale (Re 2.5 ≈ ≈ kpc) middle component∼ with f 0.2 − 0.25; and a dominant ( f =0.6), extended (Re 10 kpc) outer envelope. -
ASEM Newsletter December2015
ASEM Newsletter December2015 Comet C/2013 US10 Catalina December 1st, 2015 image from Gregg Ruppel December Calendar Social December 3 – 7-9pm Beginner Meeting @ Weldon Springs Interpretive Center, 7295 HWY 94 South, St. Charles, MO 63304 December 12 – Monthly Meeting. 5pm Open House, hors d’oeuvres @ Weldon Springs Interpretive Center, 7295 HWY 94 South, St. Charles, MO 63304. 6pm ham dinner provided by Marv and Barb Stewart followed by monthly meeting at 7pm. Complimentary dishes and desserts are welcome. Carla Kamp is turning over hospitality hosting duties with the January meeting. December 22- 7pm DigitalSIG Astrophoto group meeting Weldon Spring, 7295 Highway 94 South, St. Charles, MO 63304. Note this is the FOURTH Tuesday for just this month. We’ll go back to the 3rd Tuesday in January. December 23- 7PM DIY-ATMSIG Weldon Spring, 7295 Highway 94 South, St. Charles, MO 63304 December 4, 11, 18, 25- 7 pm start times Broemmelsiek Park Public viewing, weather permitting. ASTRONOMICAL DELIGHTS If you’re very careful, on December 7 a very old crescent moon will occult Venus in daylight, late morning. You’ll need to look to the west of the sun-don’t catch the sun in your binoculars- around 11:10 or so for the disappearance on the bright side of the moon. Start your search before 11am so you know where Venus and the moon are. Venus will be occulted for about 90 minutes. There’s a really good lunar libration on December 21 at the north Polar region. Good night to poke around the north polar landscape craters that are not normally discernible. -
National Radio Astronomy Observatory Observing
NATIONAL RADIO ASTRONOMY OBSERVATORY OBSERVING SUMMARY-1989 STATISTICS February 1990 Cover The Radio Galaxy Fornax A The cover photograph is a superposition of the VLA radio emission (shown as red) from the radio galaxy Fornax A and the visible light in the vicinity of NGC 1316 (shown as blue-white). The two main radio emitting lobes are produced by relativistic electrons in magnetic fields which have been transported hundreds of thousands of light years outward from the elliptical galaxy NGC 1316 which lies between the two regions. The energy for the relativistic flow apparently was provided by the gravitational capture of small galaxies by NGC 1316. The shock waves and trails of the infallen galaxies produce the features in the radio lobes seen as filaments and rings. The small galaxy near NGC 1316 may soon be captured. Observation details: Observers: E. Fomalont (NRAO), R. Ekers (Australia Telescope), K. Ebneter and W. Van Breugel (U. California) Frequency of 1.384 GHz; five hours of D-configuration and five hours of C-configuration Resolution of 15"; field of view is 60' x 40' NATIONAL RADIO ASTRONOMY OBSERVATORY OBSERVING SUMMARY 1989 STATISTICS FEBRUARY 1990 SOME HIGHLIGHTS OF THE 1989 RESEARCH PROGRAM A second Einstein Ring has been identified from new A-configuration VLA observations of MG1652+138, the second candidate for an Einstein ring gravitational lens system to be selected from the MIT-Green Bank 5 GHz survey. Optical images and spectra established the redshift of a faint blue quasar between the two radio sources, while the VLA results have both detected the quasar core at its optical location and improved the ring image quality.