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Observational Studies of the Galaxy Peculiar Velocity Field
OBSERVATIONAL STUDIES OF THE GALAXY PECULIAR VELOCITY FIELD by Philip Andrew James Astrophysics Group Blackett Laboratory Imperial College of Science, Technology and Medicine London SW7 2BZ A thesis submitted for the degree of Doctor of Philosophy of the University of London and for the Diploma of Imperial College November 1988 1 ABSTRACT This thesis describes two observational studies of the peculiar velocity field of galaxies over scales of 50-100 Jr1 Mpc, and the consequences of these measurements for cosmological theories. An introduction is given to observational cosmology, emphasising the crucial questions of the nature of the dark matter and the formation of structure. The principal cosmological models are discussed, and the role of observations in developing these models is stressed. Consideration is given to those observations that are likely to prove good discriminators between the competing models, particular emphasis being given to studies of the coherent velocities of samples of galaxies. The first new study presented here uses optical photometry and redshifts, from the literature, for First Ranked Cluster Galaxies (FRCG’s). These galaxies are excellent standard candles, and thus ideal for peculiar velocity studies. A simple one dimensional analysis detects no relative motion between the Local Group of galaxies and 60 FRCG’s with redshifts of up to 15000 kms-1. This is shown to imply a streaming motion of the cluster galaxies of at least 600 kms_1 relative to the CBR. The second observational study is a reanalysis of the Rubin et al. (1976a,b) sample of Sc galaxies. Near-IR photometry is used in our reanalysis to minimise the effects of extinction and to facilitate the use of luminosity indicators in reducing the effects of selection biases. -
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. -
Arxiv:2001.00331V2 [Astro-Ph.GA] 27 Feb 2020 Et Al
Draft version February 28, 2020 Typeset using LATEX twocolumn style in AASTeX62 The Carnegie-Irvine Galaxy Survey. IX. Classification of Bulge Types and Statistical Properties of Pseudo Bulges Hua Gao (高f),1, 2 Luis C. Ho,2, 1 Aaron J. Barth,3 and Zhao-Yu Li4 1Department of Astronomy, School of Physics, Peking University, Beijing 100871, China 2Kavli Institute for Astronomy and Astrophysics, Peking University, Beijing 100871, China 3Department of Physics and Astronomy, University of California at Irvine, 4129 Frederick Reines Hall, Irvine, CA 92697-4575, USA 4Department of Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China ABSTRACT We study the statistical properties of 320 bulges of disk galaxies in the Carnegie-Irvine Galaxy Survey, using robust structural parameters of galaxies derived from image fitting. We apply the Kormendy relation to classify classical and pseudo bulges and characterize bulge dichotomy with respect to bulge structural properties and physical properties of host galaxies. We confirm previous findings that pseudo bulges on average have smaller S´ersic indices, smaller bulge-to-total ratios, and fainter surface brightnesses when compared with classical bulges. Our sizable sample statistically shows that pseudo bulges are more intrinsically flattened than classical bulges. Pseudo bulges are most frequent (incidence & 80%) in late-type spirals (later than Sc). Our measurements support the picture in which pseudo bulges arose from star formation induced by inflowing gas, while classical bulges were born out of violent processes such as mergers and coalescence of clumps. We reveal differences with the literature that warrant attention: (1) the bimodal distribution of S´ersicindices presented by previous studies is not reproduced in our study; (2) classical and pseudo bulges have similar relative bulge sizes; and (3) the pseudo bulge fraction is considerably smaller in early-type disks compared with previous studies based on one-dimensional surface brightness profile fitting. -
Cold Gas Accretion in Galaxies
Astron Astrophys Rev (2008) 15:189–223 DOI 10.1007/s00159-008-0010-0 REVIEW ARTICLE Cold gas accretion in galaxies Renzo Sancisi · Filippo Fraternali · Tom Oosterloo · Thijs van der Hulst Received: 28 January 2008 / Published online: 17 April 2008 © The Author(s) 2008 Abstract Evidence for the accretion of cold gas in galaxies has been rapidly accumulating in the past years. H I observations of galaxies and their environment have brought to light new facts and phenomena which are evidence of ongoing or recent accretion: (1) A large number of galaxies are accompanied by gas-rich dwarfs or are surrounded by H I cloud complexes, tails and filaments. This suggests ongoing minor mergers and recent arrival of external gas. It may be regarded, therefore, as direct evidence of cold gas accretion in the local universe. It is probably the same kind of phenomenon of material infall as the stellar streams observed in the halos of our galaxy and M 31. (2) Considerable amounts of extra-planar H I have been found in nearby spiral galaxies. While a large fraction of this gas is undoubtedly produced by galactic fountains, it is likely that a part of it is of extragalactic origin. Also the Milky Way has extra-planar gas complexes: the Intermediate- and High-Velocity Clouds (IVCs and HVCs). (3) Spirals are known to have extended and warped outer layers of H I. It is not clear how these have formed, and how and for how long the warps can R. Sancisi (B) Osservatorio Astronomico di Bologna, Via Ranzani 1, 40127 Bologna, Italy e-mail: [email protected] R. -
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¼¼ÇwªÂÐw¦¹Á¼ºËw£ÀÊËw II - C ll r l 400 e e l G C k i 200 r he Dec. P.A. w R.A. Size Size Chart N a he ss d l Object Type Con. Mag. Class t NGC Description l AS o o sc e s r ( h m ) max min No. C a ( ' ) ( ) sc R AAS e r e M C T e B H H NGC 7192 GALXY IND 22 06.8 -64 19 11.2 1.9 m 1.8 m Elliptical pB,S,R,pmbM 134 NGC 7219 GALXY TUC 22 13.1 -64 51 12.5 1.7 m 1 m 27 SBa pB,S,R,2st nr 134 NGC 7329 GALXY TUC 22 40.4 -66 29 11.3 3.7 m 2.7 m 107 SBbc Ring pB,pS,mE90 134 NGC 7417 GALXY TUC 22 57.8 -65 02 12.3 1.9 m 1.3 m 2 SBab Ring pB,cS,R,gpmbM 134 NGC 7637 GALXY OCT 23 26.5 -81 55 12.5 2.1 m 1.9 m Sc vF,pL,R,vlbM,* nr 134 «ÆÊ¿ÀÄÀww«¸ÂÀ ¼¼ÇwªÂÐw¦¹Á¼ºËw£ÀÊËw II - C ll r l 400 e e l G C k i 200 r he Dec. P.A. w R.A. Size Size Chart N a he ss d l Object Type Con. Mag. Class t NGC Description l AS o o sc e s r ( h m ) max min No. C a ( ' ) ( ) sc R AAS e r e M C T e B H H Mel 227 OPNCL OCT 20 12.1 -79 19 5.3 50.0 m II 2 p 135 NGC 6872 GALXY PAV 20 17.0 -70 46 11.8 6.3 m 2.2 m 66 SBb/P F,pS,lE,glbM,1st of 4 135 NGC 6876 GALXY PAV 20 18.3 -70 52 11.1 3 m 2.6 m 80 E3 pB,S,R,eS* sf,2nd of 4 135 NGC 6877 GALXY PAV 20 18.6 -70 51 12.2 2 m 1 m 169 E6 vF,vS,R,3rd of 4 135 NGC 6880 GALXY PAV 20 19.5 -70 52 12.2 2.1 m 1.3 m 35 SBO-a F,S,R,r,vS* att,4 of 4 135 NGC 6920 GALXY OCT 20 44.0 -80 00 12.5 1.8 m 1.5 m SO pB,cS,R,psmbM 135 NGC 6943 GALXY PAV 20 44.6 -68 45 11.4 4 m 2.2 m 130 SBc pF,L,mE,vglbM vS* 135 IC 5052 GALXY PAV 20 52.1 -69 12 11.2 5.9 m 0.9 m 143 SBcd F,L,eE 140 deg 135 NGC 7020 GALXY PAV 21 11.3 -64 02 11.8 3.5 m 1.6 m 165 SBO-a Ring pB,cS,lE,pgbM 135 NGC 7083 GALXY IND 21 35.7 -63 54 11.2 3.6 m 2.1 m 5 Sbc pF,cL,vlE,vgpmbM,r 135 NGC 7096 GALXY IND 21 41.3 -63 55 11.9 1.8 m 1.6 m 130 Sa vF,S,R,vS** nf 135 NGC 7098 GALXY OCT 21 44.3 -75 07 11.3 4 m 2.6 m 74 SB Ring pF,R,g,psmbM,am st 135 NGC 7095 GALXY OCT 21 52.4 -81 32 11.5 4 m 3.3 m Sc F,pL,R,vglbM,*13 inv 135 «ÆÊ¿ÀÄÀww«¸ÂÀ ¼¼ÇwªÂÐw¦¹Á¼ºËw£ÀÊËw II - C ll r l 400 e e l G C k i 200 r he Dec. -
X-Ray Luminosities for a Magnitude-Limited Sample of Early-Type Galaxies from the ROSAT All-Sky Survey
Mon. Not. R. Astron. Soc. 302, 209±221 (1999) X-ray luminosities for a magnitude-limited sample of early-type galaxies from the ROSAT All-Sky Survey J. Beuing,1* S. DoÈbereiner,2 H. BoÈhringer2 and R. Bender1 1UniversitaÈts-Sternwarte MuÈnchen, Scheinerstrasse 1, D-81679 MuÈnchen, Germany 2Max-Planck-Institut fuÈr Extraterrestrische Physik, D-85740 Garching bei MuÈnchen, Germany Accepted 1998 August 3. Received 1998 June 1; in original form 1997 December 30 Downloaded from https://academic.oup.com/mnras/article/302/2/209/968033 by guest on 30 September 2021 ABSTRACT For a magnitude-limited optical sample (BT # 13:5 mag) of early-type galaxies, we have derived X-ray luminosities from the ROSATAll-Sky Survey. The results are 101 detections and 192 useful upper limits in the range from 1036 to 1044 erg s1. For most of the galaxies no X-ray data have been available until now. On the basis of this sample with its full sky coverage, we ®nd no galaxy with an unusually low ¯ux from discrete emitters. Below log LB < 9:2L( the X-ray emission is compatible with being entirely due to discrete sources. Above log LB < 11:2L( no galaxy with only discrete emission is found. We further con®rm earlier ®ndings that Lx is strongly correlated with LB. Over the entire data range the slope is found to be 2:23 60:12. We also ®nd a luminosity dependence of this correlation. Below 1 log Lx 40:5 erg s it is consistent with a slope of 1, as expected from discrete emission. -
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 -
Making a Sky Atlas
Appendix A Making a Sky Atlas Although a number of very advanced sky atlases are now available in print, none is likely to be ideal for any given task. Published atlases will probably have too few or too many guide stars, too few or too many deep-sky objects plotted in them, wrong- size charts, etc. I found that with MegaStar I could design and make, specifically for my survey, a “just right” personalized atlas. My atlas consists of 108 charts, each about twenty square degrees in size, with guide stars down to magnitude 8.9. I used only the northernmost 78 charts, since I observed the sky only down to –35°. On the charts I plotted only the objects I wanted to observe. In addition I made enlargements of small, overcrowded areas (“quad charts”) as well as separate large-scale charts for the Virgo Galaxy Cluster, the latter with guide stars down to magnitude 11.4. I put the charts in plastic sheet protectors in a three-ring binder, taking them out and plac- ing them on my telescope mount’s clipboard as needed. To find an object I would use the 35 mm finder (except in the Virgo Cluster, where I used the 60 mm as the finder) to point the ensemble of telescopes at the indicated spot among the guide stars. If the object was not seen in the 35 mm, as it usually was not, I would then look in the larger telescopes. If the object was not immediately visible even in the primary telescope – a not uncommon occur- rence due to inexact initial pointing – I would then scan around for it. -
Black Hole Mass, Host Galaxy Classification and AGN Activity
Mon. Not. R. Astron. Soc. 407, 2399–2410 (2010) doi:10.1111/j.1365-2966.2010.17068.x Black hole mass, host galaxy classification and AGN activity B. McKernan,1,2 K. E. S. Ford1,2 and C. S. Reynolds3 1Department of Science, Borough of Manhattan Community College, City University of New York, New York, NY 10007, USA 2Department of Astrophysics, American Museum of Natural History, New York, NY 10024, USA 3Department of Astronomy, University of Maryland, College Park, MD 20742, USA Accepted 2010 May 21. Received 2010 May 11; in original form 2009 October 6 Downloaded from https://academic.oup.com/mnras/article/407/4/2399/1000419 by guest on 27 September 2021 ABSTRACT We investigate the role of host galaxy classification and black hole mass (MBH) in a hetero- geneous sample of 276 mostly nearby (z < 0.1) X-ray and IR-selected active galactic nuclei (AGN). Around 90 per cent of Seyfert 1 AGN in bulge-dominated host galaxies (without disc contamination) span a very narrow range in the observed 12 μm to 2–10 keV luminosity ratio (1 < RIR/X < 7). This narrow dispersion incorporates all possible variations among AGN central engines, including accretion mechanism and efficiency, disc opening angle, orientation to sightline, covering fraction of absorbing material, patchiness of X-ray corona and measured variability. As a result, all models of X-ray and IR production in AGN are very strongly constrained. Among Seyfert 1 AGN, median X-ray and IR luminosities increase with black hole mass at >99 per cent confidence. Using ring morphology of the host galaxy as a proxy for lack of tidal interaction, we find that AGN luminosity in host galaxies within 70 Mpc is independent of host galaxy interaction for ∼ Gyr, suggesting that the timescale of AGN activity due to secular evolution is much shorter than that due to tidal interactions. -
Cold Gas Accretion in Galaxies
The Astronomy and Astrophysics Review (2011) DOI 10.1007/s00159-008-0010-0 REVIEWARTICLE Renzo Sancisi · Filippo Fraternali · Tom Oosterloo · Thijs van der Hulst Cold gas accretion in galaxies Received: 28 January 2008 c The Author(s) 2008 Abstract Evidence for the accretion of cold gas in galaxies has been rapidly accumulating in the past years. H I observations of galaxies and their environ- ment have brought to light new facts and phenomena which are evidence of on- going or recent accretion: (1) A large number of galaxies are accompanied by gas-rich dwarfs or are surrounded by H I cloud complexes, tails and filaments. This suggests ongoing minor mergers and recent arrival of external gas. It may be regarded, therefore, as direct evidence of cold gas accretion in the local universe. It is probably the same kind of phenomenon of material infall as the stellar streams observed in the halos of our galaxy and M 31. (2) Considerable amounts of extra- planar H I have been found in nearby spiral galaxies. While a large fraction of this gas is undoubtedly produced by galactic fountains, it is likely that a part of it is of extragalactic origin. Also the Milky Way has extra-planar gas complexes: the Intermediate- and High-Velocity Clouds (IVCs and HVCs). (3) Spirals are known to have extended and warped outer layers of H I. It is not clear how these have formed, and how and for how long the warps can be sustained. Gas infall has been R. Sancisi Osservatorio Astronomico di Bologna Via Ranzani 1 40127 Bologna, Italy san- [email protected] · R. -
Arxiv:Astro-Ph/0203514V1 29 Mar 2002 Ashv Enpooe Ysa Ta.(93 N Heller and Primary (1993) the Al
Accepted by The Astronomical Journal Preprint typeset using LATEX style emulateapj v. 14/09/00 DOUBLE BARS, INNER DISKS, AND NUCLEAR RINGS IN EARLY-TYPE DISK GALAXIES Peter Erwin Instituto de Astrofisica de Canarias, C/ Via L´actea s/n, 38200 La Laguna, Tenerife, Spain [email protected] and Linda S. Sparke University of Wisconsin-Madison, 475 North Charter Street, Madison, WI 53706 [email protected] Accepted by The Astronomical Journal ABSTRACT We present results from a survey of an unbiased sample of thirty-eight early-type (S0–Sa), low- inclination, optically barred galaxies in the field, using images both from the ground and from space. Our goal was to find and characterize central stellar and gaseous structures: secondary bars, inner disks, and nuclear rings. We find that bars inside bars are surprisingly common: at least one quarter of the sample galaxies (possibly as many as 40%) are double-barred, with no preference for Hubble type or the strength of the primary bar. A typical secondary bar is ∼ 12% of the size of its primary bar and extends to 240–750 pc in radius. Secondary bars are not systematically either parallel or perpendicular to the primary; we see cases where they lead the primary bar in rotation and others where they trail, which supports the hypothesis that the two bars of a double-bar system rotate independently. We see no significant effect of secondary bars on nuclear activity: our double-barred galaxies are no more likely to harbor a Seyfert or LINER nucleus than our single-barred galaxies. -
Atlante Grafico Delle Galassie
ASTRONOMIA Il mondo delle galassie, da Kant a skylive.it. LA RIVISTA DELL’UNIONE ASTROFILI ITALIANI Questo è un numero speciale. Viene qui presentato, in edizione ampliata, quan- [email protected] to fu pubblicato per opera degli Autori nove anni fa, ma in modo frammentario n. 1 gennaio - febbraio 2007 e comunque oggigiorno di assai difficile reperimento. Praticamente tutte le galassie fino alla 13ª magnitudine trovano posto in questo atlante di più di Proprietà ed editore Unione Astrofili Italiani 1400 oggetti. La lettura dell’Atlante delle Galassie deve essere fatto nella sua Direttore responsabile prospettiva storica. Nella lunga introduzione del Prof. Vincenzo Croce il testo Franco Foresta Martin Comitato di redazione e le fotografie rimandano a 200 anni di studio e di osservazione del mondo Consiglio Direttivo UAI delle galassie. In queste pagine si ripercorre il lungo e paziente cammino ini- Coordinatore Editoriale ziato con i modelli di Herschel fino ad arrivare a quelli di Shapley della Via Giorgio Bianciardi Lattea, con l’apertura al mondo multiforme delle altre galassie, iconografate Impaginazione e stampa dai disegni di Lassell fino ad arrivare alle fotografie ottenute dai colossi della Impaginazione Grafica SMAA srl - Stampa Tipolitografia Editoria DBS s.n.c., 32030 metà del ‘900, Mount Wilson e Palomar. Vecchie fotografie in bianco e nero Rasai di Seren del Grappa (BL) che permettono al lettore di ripercorrere l’alba della conoscenza di questo Servizio arretrati primo abbozzo di un Universo sempre più sconfinato e composito. Al mondo Una copia Euro 5.00 professionale si associò quanto prima il mondo amatoriale. Chi non è troppo Almanacco Euro 8.00 giovane ricorderà le immagini ottenute dal cielo sopra Bologna da Sassi, Vac- Versare l’importo come spiegato qui sotto specificando la causale.