Mapping the Universe: Improving Photometric Redshift Accuracy and Computational Efficiency
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Quantitative Morphology of Galaxies in the Core of the Coma Cluster
To appear in Astrophys. Journal Quantitative Morphology of Galaxies in the Core of the Coma Cluster Carlos M. Guti´errez, Ignacio Trujillo1, Jose A. L. Aguerri Instituto de Astrof´ısica de Canarias, E-38205, La Laguna, Tenerife, Spain Alister W. Graham Department of Astronomy, University of Florida, Gainesville, Florida, USA and Nicola Caon Instituto de Astrof´ısica de Canarias, E-38205, La Laguna, Tenerife, Spain ABSTRACT We present a quantitative morphological analysis of 187 galaxies in a region covering the central 0.28 square degrees of the Coma cluster. Structural param- eters from the best-fitting S´ersic r1/n bulge plus, where appropriate, exponential disc model, are tabulated here. This sample is complete down to a magnitude of R=17 mag. By examining the Edwards et al. (2002) compilation of galaxy redshifts in the direction of Coma, we find that 163 of the 187 galaxies are Coma arXiv:astro-ph/0310527v1 19 Oct 2003 cluster members, and the rest are foreground and background objects. For the Coma cluster members, we have studied differences in the structural and kine- matic properties between early- and late-type galaxies, and between the dwarf and giant galaxies. Analysis of the elliptical galaxies reveals correlations among the structural parameters similar to those previously found in the Virgo and Fornax clusters. Comparing the structural properties of the Coma cluster disc galaxies with disc galaxies in the field, we find evidence for an environmental dependence: the scale lengths of the disc galaxies in Coma are 30% smaller. A kinematical analysis shows marginal differences between the velocity distri- butions of ellipticals with S´ersic index n < 2 (dwarfs) and those with n > 2 1Present address: Max–Planck–Institut f¨ur Astronomie, K¨onigstuhl 17, D–69117, Heidelberg, Germany –2– (giants); the dwarf galaxies having a greater (cluster) velocity dispersion. -
Spatially Resolved Spectroscopy of Coma Cluster Early–Type Galaxies
ASTRONOMY & ASTROPHYSICS FEBRUARY I 2000, PAGE 449 SUPPLEMENT SERIES Astron. Astrophys. Suppl. Ser. 141, 449–468 (2000) Spatially resolved spectroscopy of Coma cluster early–type galaxies I. The database ? D. Mehlert1,2,??,???,????, R.P. Saglia1,R.Bender1,andG.Wegner3 1 Universit¨atssternwarte M¨unchen, 81679 M¨unchen, Germany 2 Present address: Landessternwarte Heidelberg, 69117 Heidelberg, Germany 3 Department of Physics and Astronomy, 6127 Wilder Laboratory, Dartmouth College, Hanover, NH 03755-3528, U.S.A. Received March 8; accepted September 30, 1999 Abstract. We present long slit spectra for a magnitude Key words: galaxies: elliptical and lenticular, cD; limited sample of 35 E and S0 galaxies of the Coma cluster. kinematics and dynamics; stellar content; abundances; The high quality of the data allowed us to derive spatially formation resolved spectra for a substantial sample of Coma galaxies for the first time. From these spectra we obtained rota- tion curves, the velocity dispersion profiles and the H3 and H4 coefficients of the Hermite decomposition of the 1. Introduction line of sight velocity distribution. Moreover, we derive the radial line index profiles of Mg, Fe and Hβ line indices This is the first of a series of papers aiming at investi- out to R ≈ 1re − 3re with high signal-to-noise ratio. We gating the stellar populations, the radial distribution and describe the galaxy sample, the observations and data re- the dynamics of early-type galaxies as a function of the duction, and present the spectroscopic database. Ground- environmental density. Spanning about 4 decades in den- based photometry for a subsample of 8 galaxies is also sity, the Coma cluster is the ideal place to perform such a presented. -
1987Apj. . .320. .2383 the Astrophysical Journal, 320:238-257
.2383 The Astrophysical Journal, 320:238-257,1987 September 1 © 1987. The American Astronomical Society. AU rights reserved. Printed in U.S.A. .320. 1987ApJ. THE IRÁS BRIGHT GALAXY SAMPLE. II. THE SAMPLE AND LUMINOSITY FUNCTION B. T. Soifer, 1 D. B. Sanders,1 B. F. Madore,1,2,3 G. Neugebauer,1 G. E. Danielson,4 J. H. Elias,1 Carol J. Lonsdale,5 and W. L. Rice5 Received 1986 December 1 ; accepted 1987 February 13 ABSTRACT A complete sample of 324 extragalactic objects with 60 /mi flux densities greater than 5.4 Jy has been select- ed from the IRAS catalogs. Only one of these objects can be classified morphologically as a Seyfert nucleus; the others are all galaxies. The median distance of the galaxies in the sample is ~ 30 Mpc, and the median 10 luminosity vLv(60 /mi) is ~2 x 10 L0. This infrared selected sample is much more “infrared active” than optically selected galaxy samples. 8 12 The range in far-infrared luminosities of the galaxies in the sample is 10 LQ-2 x 10 L©. The far-infrared luminosities of the sample galaxies appear to be independent of the optical luminosities, suggesting a separate luminosity component. As previously found, a correlation exists between 60 /¿m/100 /¿m flux density ratio and far-infrared luminosity. The mass of interstellar dust required to produce the far-infrared radiation corre- 8 10 sponds to a mass of gas of 10 -10 M0 for normal gas to dust ratios. This is comparable to the mass of the interstellar medium in most galaxies. -
Coma Cluster Object Populations Down to M R~-9.5
Astronomy & Astrophysics manuscript no. astrophadami c ESO 2018 November 5, 2018 ⋆ Coma cluster object populations down to MR ∼ −9.5 C. Adami1, J.P. Picat2, F. Durret3,4, A. Mazure1, R. Pell´o2, and M. West5,6 1 LAM, Traverse du Siphon, 13012 Marseille, France 2 Observatoire Midi-Pyr´en´ees, 14 Av. Edouard Belin, 31400 Toulouse, France 3 Institut d’Astrophysique de Paris, CNRS, Universit´ePierre et Marie Curie, 98bis Bd Arago, 75014 Paris, France 4 Observatoire de Paris, LERMA, 61 Av. de l’Observatoire, 75014 Paris, France 5 Department of Physics and Astronomy, University of Hawaii, 200 West Kawili Street, LS2, Hilo HI 96720-4091, USA 6 Gemini Observatory, Casilla 603, La Serena, Chile Accepted . Received ; Draft printed: November 5, 2018 ABSTRACT Context. This study follows a recent analysis of the galaxy luminosity functions and colour-magnitude red sequences in the Coma cluster (Adami et al. 2007). Aims. We analyze here the distribution of very faint galaxies and globular clusters in an east-west strip of ∼ 42 × 7 arcmin2 crossing the Coma cluster center (hereafter the CS strip) down to the unprecedented faint absolute magnitude of MR ∼−9.5. Methods. This work is based on deep images obtained at the CFHT with the CFH12K camera in the B, R, and I bands. Results. The analysis shows that the observed properties strongly depend on the environment, and thus on the cluster history. When the CS is divided into four regions, the westernmost region appears poorly populated, while the regions around the brightest galaxies NGC 4874 and NGC 4889 (NGC 4874 and NGC 4889 being masked) are dominated by faint blue galaxies. -
Aqr – Objektauswahl NGC Teil 1
Aqr – Objektauswahl NGC Teil 1 NGC 6945 NGC 6978 NGC 7069 NGC 7170 NGC 7198 NGC 7251 NGC 7293 NGC 7349 NGC 6959 NGC 6981 NGC 7077 NGC 7171 NGC 7211 NGC 7252 NGC 7298 NGC 7351 Teil 2 NGC 6961 NGC 6985 NGC 7081 NGC 7180 NGC 7215 NGC 7255 NGC 7300 NGC 7359 NGC 6962 NGC 6994 NGC 7089 NGC 7181 NGC 7218 NGC 7256 NGC 7301 NGC 7364 NGC 6964 NGC 7001 NGC 7111 NGC 7182 NGC 7220 NGC 7260 NGC 7302 NGC 7365 NGC 6965 NGC 7009 NGC 7120 NGC 7183 NGC 7222 NGC 7266 NGC 7308 NGC 7371 NGC 6967 NGC 7010 NGC 7121 NGC 7184 NGC 7230 NGC 7269 NGC 7309 NGC 7377 NGC 6968 NGC 7047 NGC 7164 NGC 7185 NGC 7239 NGC 7284 NGC 7310 NGC 7378 NGC 6976 NGC 7051 NGC 7165 NGC 7188 NGC 7246 NGC 7285 NGC 7341 NGC 7381 NGC 6977 NGC 7065 NGC 7167 NGC 7189 NGC 7247 NGC 7288 NGC 7344 NGC 7391 Sternbild- Zur Objektauswahl: Nummer anklicken Übersicht Zur Übersichtskarte: Objekt in Aufsuchkarte anklicken Zum Detailfoto: Objekt in Übersichtskarte anklicken Aqr – Objektauswahl NGC Teil 2 NGC 7392 NGC 7491 NGC 7600 NGC 7721 NGC 7761 NGC 7393 NGC 7492 NGC 7606 NGC 7723 NGC 7763 Teil 1 NGC 7399 NGC 7494 NGC 7646 NGC 7724 NGC 7776 NGC 7406 NGC 7498 NGC 7656 NGC 7725 NGC 7416 NGC 7520 NGC 7663 NGC 7727 NGC 7425 NGC 7573 NGC 7665 NGC 7730 NGC 7441 NGC 7576 NGC 7692 NGC 7736 NGC 7443 NGC 7585 NGC 7709 NGC 7754 NGC 7444 NGC 7592 NGC 7717 NGC 7758 NGC 7450 NGC 7596 NGC 7719 NGC 7759 Sternbild- Zur Objektauswahl: Nummer anklicken Übersicht Zur Übersichtskarte: Objekt in Aufsuchkarte anklicken Zum Detailfoto: Objekt in Übersichtskarte anklicken Aqr Übersichtskarte Auswahl NGC 6945_6968_6976_6977_6978 -
Agns with Composite Spectra? P
Astron. Astrophys. 319, 52–66 (1997) ASTRONOMY AND ASTROPHYSICS AGNs with composite spectra? P. Veron´ 1, A.C. Gonc¸alves1;2, and M.-P. Veron-Cetty´ 1 1 Observatoire de Haute-Provence (CNRS), F-04870 Saint Michel l’Observatoire, France 2 Centro de Astrof´ısica da Universidade do Porto, Rua do Campo Alegre 823, 4150 Porto, Portugal Received 11 April 1996 / Accepted 22 July 1996 Abstract. The use of the Baldwin et al. (1981) or Veilleux & The use of Baldwin et al. (1981) or Veilleux & Oster- Osterbrock (1987) diagnostic diagrams allows the unambigu- brock (1987) diagnostic diagrams generally yields an imme- ous classification of the nuclear emission line regions of most diate classification of the nuclear emission line clouds; “transi- galaxies into one of three categories: nuclear HII regions or star- tion” objects exist however, which cannot be classified unambi- bursts, Seyfert 2 galaxies and Liners. However, a small fraction guously from their line ratios (Heckman et al., 1983; Keel, of them have a “transition” spectrum. 1984; Veilleux & Osterbrock, 1987; Ho et al., 1993a). When We present spectral observations of 15 “transition” observed with sufficient spectral resolution, such objects show 1 objects at high-dispersion (66Amm˚ − ) around the Hα, different profiles for the permitted and forbidden lines (Heck- [NII]λλ6548; 6584 and/or Hβ, [OIII]λλ4959; 5007 emission man et al., 1981; Veron´ et al., 1981a,b; Veron-Cetty´ & Veron,´ lines. We show that most of these spectra are composite, due 1985, 1986b), this being due to the superposition of several to the simultaneous presence on the slit of a Seyfert nucleus and components that have different relative line strengths and are a HII region. -
Ngc Catalogue Ngc Catalogue
NGC CATALOGUE NGC CATALOGUE 1 NGC CATALOGUE Object # Common Name Type Constellation Magnitude RA Dec NGC 1 - Galaxy Pegasus 12.9 00:07:16 27:42:32 NGC 2 - Galaxy Pegasus 14.2 00:07:17 27:40:43 NGC 3 - Galaxy Pisces 13.3 00:07:17 08:18:05 NGC 4 - Galaxy Pisces 15.8 00:07:24 08:22:26 NGC 5 - Galaxy Andromeda 13.3 00:07:49 35:21:46 NGC 6 NGC 20 Galaxy Andromeda 13.1 00:09:33 33:18:32 NGC 7 - Galaxy Sculptor 13.9 00:08:21 -29:54:59 NGC 8 - Double Star Pegasus - 00:08:45 23:50:19 NGC 9 - Galaxy Pegasus 13.5 00:08:54 23:49:04 NGC 10 - Galaxy Sculptor 12.5 00:08:34 -33:51:28 NGC 11 - Galaxy Andromeda 13.7 00:08:42 37:26:53 NGC 12 - Galaxy Pisces 13.1 00:08:45 04:36:44 NGC 13 - Galaxy Andromeda 13.2 00:08:48 33:25:59 NGC 14 - Galaxy Pegasus 12.1 00:08:46 15:48:57 NGC 15 - Galaxy Pegasus 13.8 00:09:02 21:37:30 NGC 16 - Galaxy Pegasus 12.0 00:09:04 27:43:48 NGC 17 NGC 34 Galaxy Cetus 14.4 00:11:07 -12:06:28 NGC 18 - Double Star Pegasus - 00:09:23 27:43:56 NGC 19 - Galaxy Andromeda 13.3 00:10:41 32:58:58 NGC 20 See NGC 6 Galaxy Andromeda 13.1 00:09:33 33:18:32 NGC 21 NGC 29 Galaxy Andromeda 12.7 00:10:47 33:21:07 NGC 22 - Galaxy Pegasus 13.6 00:09:48 27:49:58 NGC 23 - Galaxy Pegasus 12.0 00:09:53 25:55:26 NGC 24 - Galaxy Sculptor 11.6 00:09:56 -24:57:52 NGC 25 - Galaxy Phoenix 13.0 00:09:59 -57:01:13 NGC 26 - Galaxy Pegasus 12.9 00:10:26 25:49:56 NGC 27 - Galaxy Andromeda 13.5 00:10:33 28:59:49 NGC 28 - Galaxy Phoenix 13.8 00:10:25 -56:59:20 NGC 29 See NGC 21 Galaxy Andromeda 12.7 00:10:47 33:21:07 NGC 30 - Double Star Pegasus - 00:10:51 21:58:39 -
The Complex Nature of the Seyfert Galaxy Ngc 7592
THE COMPLEX NATURE OF THE SEYFERT GALAXY NGC 7592 Piero Rafanelli Department of Astronomy, University of Padova, Italy Paolo Marziani International School for Advanced Studies, Trieste, Italy 1. Morphology NGC 7592 = VV 731 = MCG-01-59-017 is a system of close interacting galaxies. Two main galactic bodies are present in the CCD R-band image taken at the 1.8m, F/9 telescope of the Asiago Observatory and shown in Figure 1: • a north-western (NW) component (=VV 731B), whose starlike nucleus (A) shows a Seyfert-type spectrum (Archipova et al., 1981). A is surrounded by a nearly spheroidal envelope, with an extension in the west at P.A. = 290° detected up to a distance from A of « 9 arcsec, which corresponds to w 2.5h~xkpc of projected linear distance x x x (1 arcsec « .35 h~ kpc at the redshift z = 0.0244; H0 = 100 h km s- Mpc~ ). This extension seems to bend in the northern direction and to join a bright wing, detected up to w 22 arcsec from A, which turns to east and resembles a spiral arm or a tidal tail. • The envelope around A is connected (over ~ 20 arcsec as 7h~xkpc) to a second galactic body (SE) located in the south-east of it. Its nucleus (B), identified by Markarian and Lipovetskii (1976) as the nucleus of Mkn 928, is located at djuB ~ 11 arcsec(~ Ah~xkpc) from A at P.A. = 100°. The morphology of this component is highly peculiar. In the central region, B is linked to two fainter knots which extend up to <T ~ 4 arcsec at P.A. -
Mid-Infrared Images of Luminous Infrared Galaxies in a Merging
Mid-Infrared Images of Luminous Infrared Galaxies in a Merging Sequence Chorng-Yuan Hwang1,2, K.Y. Lo1,3, Yu Gao3,4, Robert A. Gruendl3, and Nanyao Lu5 Received ; accepted arXiv:astro-ph/9812476v1 30 Dec 1998 1Institute of Astronomy and Astrophysics, Academia Sinica, P.O. Box 1-87, Nankang, Taipei, Taiwan; [email protected], [email protected] 2Institute of Astronomy, National Central University, Chung-Li, Taiwan 3Department of Astronomy, University of Illinois, 1002 W. Green Street, Urbana, IL 61801, U.S.A.; [email protected], [email protected] 4current address: Department of Astromnomy, University of Toronto, 60 St. George Street, Toronro, ON M5S 3H8, CANADA 5IPAC, MS100-22 Caltech, Pasadena, CA 91125, U.S.A; [email protected] – 2 – ABSTRACT We report mid-infrared observations of several luminous infrared galaxies (LIGs) carried out with the Infrared Space Observatory (ISO). Our sample was chosen to rep- resent different phases of a merger sequence of galaxy-galaxy interaction with special emphasis on early/intermediate stages of merging. The mid-infrared emission of these LIGs shows extended structures for the early and intermediate mergers, indicating that most of the mid-infrared luminosities are not from a central active galactic nucleus (AGN). Both the infrared hardness (indicated by the IRAS 12, 25, and 60 µm flux den- sity ratios) and the peak-to-total flux density ratios of these LIGs increase as projected separation of these interacting galaxies become smaller, consistent with increasing star formation activities that are concentrated to a smaller area as the merging process ad- vances. -
Spitzer IRS Spectral Mapping of the Toomre Sequence: Spatial
A Preprint typeset using LTEX style emulateapj v. 5/2/11 SPITZER IRS SPECTRAL MAPPING OF THE TOOMRE SEQUENCE: SPATIAL VARIATIONS OF PAH, GAS, AND DUST PROPERTIES IN NEARBY MAJOR MERGERS S. Haan1, L. Armus1, S. Laine1, V. Charmandaris2,3, J.D. Smith4, F. Schweizer5, B. Brandl6, A.S. Evans7,8, J.A. Surace1, T. Diaz-Santos2,1, P. Beirao˜ 1, E.J. Murphy5, S. Stierwalt1, J.E. Hibbard7,8, M. Yun9, T.H. Jarrett10 ABSTRACT We have mapped the key mid-IR diagnostics in eight major merger systems of the Toomre Sequence (NGC 4676, NGC 7592, NGC 6621, NGC 2623, NGC 6240, NGC 520, NGC 3921, and NGC 7252) using the Spitzer Infrared Spectrograph (IRS). With these maps, we explore the variation of the ionized-gas, PAH, and warm-gas (H2) properties across the sequence and within the galaxies. While the global PAH interband strength and ionized gas flux ratios ([Ne III]/[Ne II]) are similar to those of normal star forming galaxies, the distribution of the spatially resolved PAH and fine structure line flux ratios is significant different from one system to the other. Rather than a constant H2/PAH flux ratio, we find that the relation between the H2 and PAH fluxes is characterized by a power law with a roughly constant exponent (0.61 ± 0.05) over all merger components and spatial scales. While following the same power law on local scales, three galaxies have a factor of ten larger integrated (i.e. global) H2/PAH flux ratio than the rest of the sample, even larger than what it is in most nearby AGNs. -
Galaxy Aggregates in the Coma Cluster
View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by CERN Document Server Galaxy Aggregates in the Coma Cluster Christopher J. Conselice1 and John S. Gallagher III Department of Astronomy, University of Wisconsin, Madison, 475 N. Charter St., Madison, WI., 54706 ABSTRACT We present evidence for a new morphologically defined form of small-scale substructure in the Coma Cluster, which we call galaxy aggregates. These aggregates are dominated by a central galaxy, which is on average three magnitudes brighter than the smaller aggregate members, nearly all of which lie to one side of the central galaxy. We have found three such galaxy aggregates dominated by the S0 galaxies RB 55, RB 60, and the star-bursting SBb, NGC 4858. RB 55 and RB 60 are both equi-distant between the two dominate D galaxies NGC 4874 and NGC 4889, while NGC 4858 is located next to the larger E0 galaxy NGC 4860. All three central galaxies have redshifts consistent with Coma Cluster membership. We describe the spatial structures of these unique objects and suggest several possible mechanisms to explain their origin. These include: chance superpositions from background galaxies, interactions between other galaxies and with the cluster gravitational potential, and ram pressure. We conclude that the most probable scenario of creation is an interaction with the cluster through its potential. Subject headings: galaxies - clusters - individual (Coma, Abell 1656) : galaxies - formation : galaxies- interactions. 1. INTRODUCTION Due to its proximity and high density, the Coma Cluster is a good location to investigate evolutionary effects in galaxy clusters, and for deriving certain cosmological parameters (Crone et al. -
QUANTITATIVE MORPHOLOGY of GALAXIES in the CORE of the COMA CLUSTER Carlos M
The Astrophysical Journal, 602:664–677, 2004 February 20 A # 2004. The American Astronomical Society. All rights reserved. Printed in U.S.A. QUANTITATIVE MORPHOLOGY OF GALAXIES IN THE CORE OF THE COMA CLUSTER Carlos M. Gutie´rrez, Ignacio Trujillo,1 and Jose A. L. Aguerri Instituto de Astrofı´sica de Canarias, E-38205, La Laguna, Tenerife, Spain Alister W. Graham Department of Astronomy, University of Florida, Gainesville, FL 32611 and Nicola Caon Instituto de Astrofı´sica de Canarias, E-38205, La Laguna, Tenerife, Spain Received 2003 July 26; accepted 2003 October 17 ABSTRACT We present a quantitative morphological analysis of 187 galaxies in a region covering the central 0.28 deg2 of the Coma Cluster. Structural parameters from the best-fitting Se´rsic r1=n bulge plus, where appropriate, expo- nential disk model, are tabulated here. This sample is complete down to a magnitude of R ¼ 17 mag. By examining the recent compilation by Edwards et al. of galaxy redshifts in the direction of Coma, we find that 163 of the 187 galaxies are Coma Cluster members and that the rest are foreground and background objects. For the Coma Cluster members, we have studied differences in the structural and kinematic properties between early- and late-type galaxies and between the dwarf and giant galaxies. Analysis of the elliptical galaxies reveals correlations among the structural parameters similar to those previously found in the Virgo and Fornax Clusters. Comparing the structural properties of the Coma Cluster disk galaxies with disk galaxies in the field, we find evidence for an environmental dependence: the scale lengths of the disk galaxies in Coma are 30% smaller.