The Interstellar and Circumnuclear Medium of Active Nuclei Traced by H I 21 Cm Absorption
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The Local Radio-Galaxy Population at 20
Mon. Not. R. Astron. Soc. 000, 1–?? (2013) Printed 2 December 2013 (MN LATEX style file v2.2) The local radio-galaxy population at 20GHz Elaine M. Sadler1⋆, Ronald D. Ekers2, Elizabeth K. Mahony3, Tom Mauch4,5, Tara Murphy1,6 1Sydney Institute for Astronomy, School of Physics, The University of Sydney, NSW 2006, Australia 2Australia Telescope National Facility, CSIRO, PO Box 76, Epping, NSW 1710, Australia 3ASTRON, the Netherlands Institute for Radio Astronomy, Postbus 2, 7990 AA, Dwingeloo, The Netherlands 4Oxford Astrophysics, Department of Physics, Keble Road, Oxford OX1 3RH 5SKA Africa, 3rd Floor, The Park, Park Road, Pinelands, 7405, South Africa 6School of Information Technologies, The University of Sydney, NSW 2006, Australia Accepted 0000 December 08. Received 0000 December 08; in original form 0000 December 08 ABSTRACT We have made the first detailed study of the high-frequency radio-source population in the local universe, using a sample of 202 radio sources from the Australia Telescope 20GHz (AT20G) survey identified with galaxies from the 6dF Galaxy Survey (6dFGS). The AT20G- 6dFGS galaxies have a median redshift of z=0.058 and span a wide range in radio luminosity, allowing us to make the first measurement of the local radio luminosity function at 20GHz. Our sample includes some classical FR-1 and FR-2 radio galaxies, but most of the AT20G-6dFGS galaxies host compact (FR-0) radio AGN which appear lack extended radio emission even at lower frequencies. Most of these FR-0 sources show no evidence for rela- tivistic beaming, and the FR-0 class appears to be a mixed population which includes young Compact Steep-Spectrum (CSS) and Gigahertz-Peaked Spectrum (GPS) radio galaxies. -
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A&A 562, A92 (2014) Astronomy DOI: 10.1051/0004-6361/201321493 & c ESO 2014 Astrophysics Li depletion in solar analogues with exoplanets Extending the sample, E. Delgado Mena1,G.Israelian2,3, J. I. González Hernández2,3,S.G.Sousa1,2,4, A. Mortier1,4,N.C.Santos1,4, V. Zh. Adibekyan1, J. Fernandes5, R. Rebolo2,3,6,S.Udry7, and M. Mayor7 1 Centro de Astrofísica, Universidade do Porto, Rua das Estrelas, 4150-762 Porto, Portugal e-mail: [email protected] 2 Instituto de Astrofísica de Canarias, C/ Via Lactea s/n, 38200 La Laguna, Tenerife, Spain 3 Departamento de Astrofísica, Universidad de La Laguna, 38205 La Laguna, Tenerife, Spain 4 Departamento de Física e Astronomia, Faculdade de Ciências, Universidade do Porto, 4169-007 Porto, Portugal 5 CGUC, Department of Mathematics and Astronomical Observatory, University of Coimbra, 3049 Coimbra, Portugal 6 Consejo Superior de Investigaciones Científicas, CSIC, Spain 7 Observatoire de Genève, Université de Genève, 51 ch. des Maillettes, 1290 Sauverny, Switzerland Received 18 March 2013 / Accepted 25 November 2013 ABSTRACT Aims. We want to study the effects of the formation of planets and planetary systems on the atmospheric Li abundance of planet host stars. Methods. In this work we present new determinations of lithium abundances for 326 main sequence stars with and without planets in the Teff range 5600–5900 K. The 277 stars come from the HARPS sample, the remaining targets were observed with a variety of high-resolution spectrographs. Results. We confirm significant differences in the Li distribution of solar twins (Teff = T ± 80 K, log g = log g ± 0.2and[Fe/H] = [Fe/H] ±0.2): the full sample of planet host stars (22) shows Li average values lower than “single” stars with no detected planets (60). -
Upholding the Unified Model for Active Galactic Nuclei: VLT/FORS2 Spectropolarimetry of Seyfert 2 Galaxies
MNRAS 461, 1387–1403 (2016) doi:10.1093/mnras/stw1388 Advance Access publication 2016 June 9 Upholding the unified model for active galactic nuclei: VLT/FORS2 spectropolarimetry of Seyfert 2 galaxies C. Ramos Almeida,1,2‹† M. J. Mart´ınez Gonzalez,´ 1,2 A. Asensio Ramos,1,2 J. A. Acosta-Pulido,1,2 S. F. Honig,¨ 3 A. Alonso-Herrero,4,5 C. N. Tadhunter6 and O. Gonzalez-Mart´ ´ın7 1Instituto de Astrof´ısica de Canarias, Calle V´ıa Lactea,´ s/n, E-38205 La Laguna, Tenerife, Spain 2Departamento de Astrof´ısica, Universidad de La Laguna, E-38205 La Laguna, Tenerife, Spain 3School of Physics and Astronomy, University of Southampton, Southampton SO17 1BJ, UK 4Centro de Astrobiolog´ıa (CAB, CSIC-INTA), ESAC Campus, E-28692 Villanueva de la Canada,˜ Madrid, Spain 5Department of Physics and Astronomy, University of Texas at San Antonio, One UTSA Circle, San Antonio, TX 78249, USA 6Department of Physics and Astronomy, University of Sheffield, Sheffield S3 7RH, UK 7Instituto de Radioastronom´ıa y Astrof´ısica (IRAF-UNAM), 3-72 (Xangari), 8701 Morelia, Mexico Accepted 2016 June 7. Received 2016 June 7; in original form 2015 September 2 ABSTRACT The origin of the unification model for active galactic nuclei (AGN) was the detection of broad hydrogen recombination lines in the optical polarized spectrum of the Seyfert 2 galaxy (Sy2) NGC 1068. Since then, a search for the hidden broad-line region (HBLR) of nearby Sy2s started, but polarized broad lines have only been detected in ∼30–40 per cent of the nearby Sy2s observed to date. -
Astronomy 2008 Index
Astronomy Magazine Article Title Index 10 rising stars of astronomy, 8:60–8:63 1.5 million galaxies revealed, 3:41–3:43 185 million years before the dinosaurs’ demise, did an asteroid nearly end life on Earth?, 4:34–4:39 A Aligned aurorae, 8:27 All about the Veil Nebula, 6:56–6:61 Amateur astronomy’s greatest generation, 8:68–8:71 Amateurs see fireballs from U.S. satellite kill, 7:24 Another Earth, 6:13 Another super-Earth discovered, 9:21 Antares gang, The, 7:18 Antimatter traced, 5:23 Are big-planet systems uncommon?, 10:23 Are super-sized Earths the new frontier?, 11:26–11:31 Are these space rocks from Mercury?, 11:32–11:37 Are we done yet?, 4:14 Are we looking for life in the right places?, 7:28–7:33 Ask the aliens, 3:12 Asteroid sleuths find the dino killer, 1:20 Astro-humiliation, 10:14 Astroimaging over ancient Greece, 12:64–12:69 Astronaut rescue rocket revs up, 11:22 Astronomers spy a giant particle accelerator in the sky, 5:21 Astronomers unearth a star’s death secrets, 10:18 Astronomers witness alien star flip-out, 6:27 Astronomy magazine’s first 35 years, 8:supplement Astronomy’s guide to Go-to telescopes, 10:supplement Auroral storm trigger confirmed, 11:18 B Backstage at Astronomy, 8:76–8:82 Basking in the Sun, 5:16 Biggest planet’s 5 deepest mysteries, The, 1:38–1:43 Binary pulsar test affirms relativity, 10:21 Binocular Telescope snaps first image, 6:21 Black hole sets a record, 2:20 Black holes wind up galaxy arms, 9:19 Brightest starburst galaxy discovered, 12:23 C Calling all space probes, 10:64–10:65 Calling on Cassiopeia, 11:76 Canada to launch new asteroid hunter, 11:19 Canada’s handy robot, 1:24 Cannibal next door, The, 3:38 Capture images of our local star, 4:66–4:67 Cassini confirms Titan lakes, 12:27 Cassini scopes Saturn’s two-toned moon, 1:25 Cassini “tastes” Enceladus’ plumes, 7:26 Cepheus’ fall delights, 10:85 Choose the dome that’s right for you, 5:70–5:71 Clearing the air about seeing vs. -
Bright Star Double Variable Globular Open Cluster Planetary Bright Neb Dark Neb Reflection Neb Galaxy Int:Pec Compact Galaxy Gr
bright star double variable globular open cluster planetary bright neb dark neb reflection neb galaxy int:pec compact galaxy group quasar ALL AND ANT APS AQL AQR ARA ARI AUR BOO CAE CAM CAP CAR CAS CEN CEP CET CHA CIR CMA CMI CNC COL COM CRA CRB CRT CRU CRV CVN CYG DEL DOR DRA EQU ERI FOR GEM GRU HER HOR HYA HYI IND LAC LEO LEP LIB LMI LUP LYN LYR MEN MIC MON MUS NOR OCT OPH ORI PAV PEG PER PHE PIC PSA PSC PUP PYX RET SCL SCO SCT SER1 SER2 SEX SGE SGR TAU TEL TRA TRI TUC UMA UMI VEL VIR VOL VUL Object ConRA Dec Mag z AbsMag Type Spect Filter Other names CFHQS J23291-0301 PSC 23h 29 8.3 - 3° 1 59.2 21.6 6.430 -29.5 Q ULAS J1319+0950 VIR 13h 19 11.3 + 9° 50 51.0 22.8 6.127 -24.4 Q I CFHQS J15096-1749 LIB 15h 9 41.8 -17° 49 27.1 23.1 6.120 -24.1 Q I FIRST J14276+3312 BOO 14h 27 38.5 +33° 12 41.0 22.1 6.120 -25.1 Q I SDSS J03035-0019 CET 3h 3 31.4 - 0° 19 12.0 23.9 6.070 -23.3 Q I SDSS J20541-0005 AQR 20h 54 6.4 - 0° 5 13.9 23.3 6.062 -23.9 Q I CFHQS J16413+3755 HER 16h 41 21.7 +37° 55 19.9 23.7 6.040 -23.3 Q I SDSS J11309+1824 LEO 11h 30 56.5 +18° 24 13.0 21.6 5.995 -28.2 Q SDSS J20567-0059 AQR 20h 56 44.5 - 0° 59 3.8 21.7 5.989 -27.9 Q SDSS J14102+1019 CET 14h 10 15.5 +10° 19 27.1 19.9 5.971 -30.6 Q SDSS J12497+0806 VIR 12h 49 42.9 + 8° 6 13.0 19.3 5.959 -31.3 Q SDSS J14111+1217 BOO 14h 11 11.3 +12° 17 37.0 23.8 5.930 -26.1 Q SDSS J13358+3533 CVN 13h 35 50.8 +35° 33 15.8 22.2 5.930 -27.6 Q SDSS J12485+2846 COM 12h 48 33.6 +28° 46 8.0 19.6 5.906 -30.7 Q SDSS J13199+1922 COM 13h 19 57.8 +19° 22 37.9 21.8 5.903 -27.5 Q SDSS J14484+1031 BOO -
Far-Ultraviolet Morphology of Star-Forming Filaments in Cool Core
Durham Research Online Deposited in DRO: 04 November 2015 Version of attached le: Published Version Peer-review status of attached le: Peer-reviewed Citation for published item: Tremblay, G.R. and O'Dea, C.P. and Baum, S.A. and Mittal, R. and McDonald, M.A. and Combes, F. and Li, Y. and McNamara, B.R. and Bremer, M.N. and Clarke, T.E. and Donahue, M. and Edge, A.C. and Fabian, A.C. and Hamer, S.L. and Hogan, M.T. and Oonk, J.B.R. and Quillen, A.C. and Sanders, J.S. and Salom¡e,P. and Voit, G.M. (2015) 'Far-ultraviolet morphology of star-forming laments in cool core brightest cluster galaxies.', Monthly notices of the Royal Astronomical Society., 451 (4). pp. 3768-3800. Further information on publisher's website: http://dx.doi.org/10.1093/mnras/stv1151 Publisher's copyright statement: This article has been published in Monthly Notices of the Royal Astronomical Society c : 2015 The Authors. Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved. Additional information: Use policy The full-text may be used and/or reproduced, and given to third parties in any format or medium, without prior permission or charge, for personal research or study, educational, or not-for-prot purposes provided that: • a full bibliographic reference is made to the original source • a link is made to the metadata record in DRO • the full-text is not changed in any way The full-text must not be sold in any format or medium without the formal permission of the copyright holders. -
Lemmings. I. the Emerlin Legacy Survey of Nearby Galaxies. 1.5-Ghz Parsec-Scale Radio Structures and Cores
MNRAS 000,1{44 (2018) Preprint 8 February 2018 Compiled using MNRAS LATEX style file v3.0 LeMMINGs. I. The eMERLIN legacy survey of nearby galaxies. 1.5-GHz parsec-scale radio structures and cores R. D. Baldi1?, D. R. A. Williams1, I. M. McHardy1, R. J. Beswick2, M. K. Argo2;3, B. T. Dullo4, J. H. Knapen5;6, E. Brinks7, T. W. B. Muxlow2, S. Aalto8, A. Alberdi9, G. J. Bendo2;10, S. Corbel11;12, R. Evans13, D. M. Fenech14, D. A. Green15, H.-R. Kl¨ockner16, E. K¨ording17, P. Kharb18, T. J. Maccarone19, I. Mart´ı-Vidal8, C. G. Mundell20, F. Panessa21, A. B. Peck22, M. A. P´erez-Torres9, D. J. Saikia18, P. Saikia17;23, F. Shankar1, R. E. Spencer2, I. R. Stevens24, P. Uttley25 and J. Westcott7 1 School of Physics and Astronomy, University of Southampton, Southampton, SO17 1BJ, UK 2 Jodrell Bank Centre for Astrophysics, School of Physics and Astronomy, The University of Manchester, Manchester, M13 9PL, UK 3 Jeremiah Horrocks Institute, University of Central Lancashire, Preston PR1 2HE, UK 4 Departamento de Astrofisica y Ciencias de la Atmosfera, Universidad Complutense de Madrid, E-28040 Madrid, Spain 5 Instituto de Astrofisica de Canarias, Via Lactea S/N, E-38205, La Laguna, Tenerife, Spain 6 Departamento de Astrofisica, Universidad de La Laguna, E-38206, La Laguna, Tenerife, Spain 7 Centre for Astrophysics Research, University of Hertfordshire, College Lane, Hatfield, AL10 9AB, UK 8 Department of Space, Earth and Environment, Chalmers University of Technology, Onsala Space Observatory, 43992 Onsala, Sweden 9 Instituto de Astrofisica de Andaluc´ıa(IAA, CSIC); Glorieta de la Astronom´ıa s/n, 18008-Granada, Spain 10 ALMA Regional Centre Node, UK 11 Laboratoire AIM (CEA/IRFU - CNRS/INSU - Universit´eParis Diderot), CEA DSM/IRFU/SAp, F-91191 Gif-sur-Yvette, France 12 Station de Radioastronomie de Nan¸cay, Observatoire de Paris, PSL Research University, CNRS, Univ. -
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A&A 505, 509–520 (2009) Astronomy DOI: 10.1051/0004-6361/200912586 & c ESO 2009 Astrophysics The Bologna complete sample of nearby radio sources II. Phase referenced observations of faint nuclear sources E. Liuzzo1,2, G. Giovannini1,2, M. Giroletti1, and G. B. Taylor3,4 1 INAF Istituto di Radioastronomia, via Gobetti 101, 40129 Bologna, Italy e-mail: [email protected] 2 Dipartimento di Astronomia, Università di Bologna, via Ranzani 1, 40127 Bologna, Italy 3 Department of Physics and Astronomy, University of New Mexico, Albuquerque NM 87131, USA 4 also Adjunct Astronomer at the National Radio Astronomy Observatory, USA Received 27 May 2009 / Accepted 30 June 2009 ABSTRACT Aims. To study statistical properties of different classes of sources, it is necessary to observe a sample that is free of selection effects. To do this, we initiated a project to observe a complete sample of radio galaxies selected from the B2 Catalogue of Radio Sources and the Third Cambridge Revised Catalogue (3CR), with no selection constraint on the nuclear properties. We named this sample “the Bologna Complete Sample” (BCS). Methods. We present new VLBI observations at 5 and 1.6 GHz for 33 sources drawn from a sample not biased toward orientation. By combining these data with those in the literature, information on the parsec-scale morphology is available for a total of 76 of 94 radio sources with a range in radio power and kiloparsec-scale morphologies. Results. The fraction of two-sided sources at milliarcsecond resolution is high (30%), compared to the fraction found in VLBI surveys selected at centimeter wavelengths, as expected from the predictions of unified models. -
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. -
Polarimetry and Unification of Low-Redshift Radio Galaxies
POLARIMETRY AND UNIFICATION OF LOW-REDSHIFT RADIO GALAXIES Marshall H. Cohen1, Patrick M. Ogle1,2, Hien D. Tran3,4 Robert W. Goodrich5, Joseph S. Miller6 ABSTRACT We have made high-quality measurements of the polarization spectra of 13 FR II radio galaxies and taken polarization images for 11 of these with the Keck telescopes. Seven of the eight narrow-line radio galaxies (NLRG) are polarized, and six of the seven show prominent broad Balmer lines in polarized light. The broad lines are also weakly visible in total flux. Some of the NLRG show bipolar regions with roughly circumferential polarization vectors, revealing a large reflection nebula illuminated by a central source. Our observations powerfully support the hidden quasar hypothesis for some NLRG. According to this hypothesis, the continuum and broad lines are blocked by a dusty molecular torus, but can be seen by reflected, hence polarized, light. Classification as NLRG, broad-line radio galaxy (BLRG), or quasar therefore depends on orientation. However, not all objects fit into this unification scheme. Our sample is biased towards objects known in advance to be polarized, but the combination of our results with those of Hill, Goodrich, & DePoy (1996) show that at least 6 out of a complete, volume and flux-limited sample of 9 FR II NLRG have broad lines, seen either in polarization or Pα. The BLRG in our sample range from 3C 382, which has a quasar-like spectrum, to the highly-reddened IRAS source FSC 2217+259. This reddening sequence suggests a continuous transition from unobscured quasar to reddened BLRG to NLRG. -
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. -
Large: Draft 2.0: Satellite Game: Writeups for End Data
Satellite Data Results - LARGE Large -> Black Holes -> X-ray -> Spectrometer -> Segmented Above is real data from the Advanced CCD Imaging Spectrometer (ACIS) and the High Energy Transmission Grating Spectrometer (HETGS) on the Chandra satellite. Chandra has nested X-ray mirrors that resemble glass barrels; they are designed this way so that incoming X-rays just graze the mirrors so they can be focused. The HETGS is an assembly that is swung into position behind the mirrors where it can intercept the reflected X-rays. The X-rays are diffracted by HETGS, which changes their direction an amount dependent on the energy of the X-ray, just like a prism separates light into its component colors. The ACIS, located at the focal point of the telescope, can then detect the location of the X-ray as well as measure its energy. The above spectrum, a graph of intensity of energy over wavelength, is of a binary star system called GRO J1655-40, which consists of a black hole pulling matter in the form of hot gas from its companion, a normal star. Most of this material is spiraling toward the black hole, creating a disk around it, though about 30% of the matter is being blown away. The dips in the spectrum show that ionized atoms of elements like oxygen and nickel in the gas around the black hole are moving away from the black hole in a high-speed wind. Magnetic forces in the disk of gas around the black hole are largely responsible for the phenomena in this case, as it is magnetic fields that are driving the winds in the disk, and magnetic friction that is heating up the inner part of the disk to the point that it emits X- rays.