Mass Distribution in Galaxy Clusters
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On the Origin and Propagation of Ultra-High Energy Cosmic Rays (Measurements & Prediction Techniques)
Dissertation On the Origin and Propagation of Ultra-High Energy Cosmic Rays (Measurements & Prediction Techniques) Nils Nierstenhoefer Wuppertal, 2011 University of Wuppertal Supervisor/First reviewer: Prof. Dr. K.-H. Kampert Second reviewer: Prof. Dr. M. Risse Motivation & Preface It is a long known fact that cosmic rays reach Earth with tremendous energies of even above 1020 eV. Despite of decades of intensive research, it was not possible to finally reveal the origin of these par- ticles. The main obstacle in this field is their rare occurrence. This is due to a very steep energy spectrum. To make this point more clear, one roughly expects to observe less than one particle per km2 in one century exceeding energies larger than 1020 eV. To overcome the limitation of low statis- tics, larger and larger cosmic ray detectors have been deployed. Today’s largest cosmic ray detector is the Pierre Auger observatory (PAO) which was constructed in the Pampa Amarilla in Argentina. It covers an area of 3000 km2 and provides the largest set of observations of ultra-high energy cosmic rays (UHECR) in history. A second difficulty in understanding the origin of UHECR should be pointed out: Galactic and extra- galactic magnetic fields might alter the direction of even the highest energy events in a way that they do not point back to their source. In 2007 and 2008, already before the completion of the full detector, the Auger collaboration pub- lished a set of three important papers [1, 2, 3]. The first paper dealt with the correlation of the arrival directions of the highest energetic events with the distribution of active galactic nuclei (AGN) closer than 75Mpc from a catalog compiled by Veron-Cetty and Veron (VC-V) [4]. -
A Search for Transiting Extrasolar Planets in the Open Cluster NGC 4755
ResearchOnline@JCU This file is part of the following reference: Jayawardene, Bandupriya S. (2015) A search for transiting extrasolar planets in the open cluster NGC 4755. DAstron thesis, James Cook University. Access to this file is available from: http://researchonline.jcu.edu.au/41511/ The author has certified to JCU that they have made a reasonable effort to gain permission and acknowledge the owner of any third party copyright material included in this document. If you believe that this is not the case, please contact [email protected] and quote http://researchonline.jcu.edu.au/41511/ A SEARCH FOR TRANSITING EXTRASOLAR PLANETS IN THE OPEN CLUSTER NGC 4755 by Bandupriya S. Jayawardene A thesis submitted in satisfaction of the requirements for the degree of Doctor of Astronomy in the Faculty of Science, Technology and Engineering June 2015 James Cook University Townsville - Australia i STATEMENT OF ACCESS I the undersigned, author of this work, understand that James Cook University will make this thesis available for use within the University Library and, via the Australian Digital Thesis network, for use elsewhere. I understand that, as an unpublished work, a thesis has significant protection under the Copyright Act and; I do not wish to place any further restriction on access to this work. 2 STATEMENT OF SOURCES DECLARATION I declare that this thesis is my own work and has not been submitted in any form for another degree or diploma at any University or other institution of tertiary education. Information derived from the published or unpublished work of others has been acknowledged in the text and list of references is given. -
OBSERVING GALAXIES in ANDROMEDA As You Look Towards
OBSERVING GALAXIES IN ANDROMEDA As you look towards Andromeda you are looking out into deep space underneath the Perseus spiral arm of our milky way. The constellation has a good density of observable galaxies. There is a group of relatively local galaxies which are less than 20 million light years away and then a big gap to the rest which are over 200 million light years away. The constellation is well place from late summer to mid-winter. M31 / M32 / M110 These galaxies are generally the first galaxies that amateur astronomers observe first. M31 is visible to the naked eye in dark skies. M31 whilst bright and large is fairly bland in appearance until you start to look a bit closer. With good conditions, the dark line of a dust lane is visible. I have to say that observing two of the globular clusters of this galaxy rank up there in my most memorable observations ever. M32 is very bright and I have seen it in binoculars as a very small bright blob. M110 can be a challenge to see with its low surface brightness. Having said that, I have seen it easily in my 80mm binoculars when the sky was transparent. NGC404 This galaxy is memorable to observe as it is close to the star Mirach and hence is known as Mirach’s ghost. It is a lovely circular low surface brightness glow that is visible with direct vision in my 10 inch reflector and was visible at low power with averted vision even with Mirach in the field of view. -
Brightness Profiles of Early-Type Galaxies Hosting Seyfert Nuclei
A&A 469, 75–88 (2007) Astronomy DOI: 10.1051/0004-6361:20066684 & c ESO 2007 Astrophysics The host galaxy/AGN connection Brightness profiles of early-type galaxies hosting Seyfert nuclei A. Capetti and B. Balmaverde INAF - Osservatorio Astronomico di Torino, Strada Osservatorio 20, 10025 Pino Torinese, Italy e-mail: [capetti;balmaverde]@oato.inaf.it Received 2 November 2006 / Accepted 15 March 2007 ABSTRACT We recently presented evidence of a connection between the brightness profiles of nearby early-type galaxies and the properties of the AGN they host. The radio loudness of the AGN appears to be univocally related to the host’s brightness profile: radio-loud nuclei are only hosted by “core” galaxies while radio-quiet AGN are only found in “power-law” galaxies. We extend our analysis here to a −1 sample of 42 nearby (Vrec < 7000 km s ) Seyfert galaxies hosted by early-type galaxies. From the nuclear point of view, they show a large deficit of radio emission (at a given X-ray or narrow line luminosity) with respect to radio-loud AGN, conforming with their identification as radio-quiet AGN. We used the available HST images to study their brightness profiles. Having excluded complex and highly nucleated galaxies, in the remaining 16 objects the brightness profiles can be successfully modeled with a Nuker law with a steep nuclear cusp characteristic of “power-law” galaxies (with logarithmic slope γ = 0.51−1.07). This result is what is expected for these radio-quiet AGN based on our previous findings, thus extending the validity of the connection between brightness profile and radio loudness to AGN of a far higher luminosity. -
Prevalence of Tidal Interactions Among Local Seyfert Galaxies
To be submitted to the Astrophysical Journal Preprint typeset using LATEX style emulateapj v. 04/21/05 PREVALENCE OF TIDAL INTERACTIONS AMONG LOCAL SEYFERT GALAXIES Cheng-Yu Kuo1,3 Institute of Astronomy & Astrophysics, Academia Sinica, PO Box 23-141, Taipei 10617, Taiwan Department of Astronomy, University of Virginia, Charlottesville, VA 22904 Jeremy Lim Institute of Astronomy & Astrophysics, Academia Sinica, PO Box 23-141, Taipei 10617, Taiwan Ya-Wen Tang1,2 Institute of Astronomy & Astrophysics, Academia Sinica, PO Box 23-141, Taipei 10617, Taiwan Department of Physics, National Taiwan University, No. 1, Sec. 4, Roosevelt Rd., Taipei 106, Taiwan and Paul T. P. Ho1,4 Institute of Astronomy & Astrophysics, Academia Sinica, PO Box 23-141, Taipei 10617, Taiwan Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 To be submitted to the Astrophysical Journal ABSTRACT No mechanisms have hitherto been conclusively demonstrated to be responsible for initiating optically-luminous nuclear (Seyfert) activity in local disk galaxies. Only a small minority of such galax- ies are visibly disturbed in optical starlight, with the observed disturbances being at best marginally stronger than those found in matched samples of inactive galaxies. Here, we report the first system- atic study of an optically-selected sample of twenty-three active galaxies in atomic hydrogen (HI) gas, which is the most sensitive and enduring tracer known of tidal interactions. Eighteen of these galaxies are (generally) classified as Seyferts, with over half (and perhaps all) having [OIII] luminosities within two orders of magnitude of Quasi-Stellar Objects. Only ∼28% of these Seyfert galaxies are visibly dis- turbed in optical DSS2 images. -
Publications of Richard W. Pogge
Publications Richard William Pogge Updated: 2021 March 10 Doctoral Dissertation “The Circumnuclear Environment of Nearby, Non-Interacting Seyfert Galaxies”, University of California, Santa Cruz, June 1988. (Abstract published in PASP, 100, 1296, 1988. See also #7, 8, 10, 11, & 12 below.) Papers Published in Peer-RevieWed Journals 1. “X-Ray, Radio, and Infrared Observations of the Rapid Burster (MXB 1730-335) During 1979 and 1980”, LaWrence, A., et al. (52 authors), 1983, ApJ, 267, 301 2. “The Spectra of Narrow-Line Seyfert 1 Galaxies”, Osterbrock, Donald E., & Pogge, Richard W. 1985, ApJ, 297, 166 3. “The Extended Narrow Emission-Line Region of NGC 7469 Revisited”, DeRobertis, M.M. Pogge, R.W. 1986, AJ, 91, 1026 4. “Star Forming Regions in Gas-Rich Lenticulars. I. Ha Imaging of an Initial Sample of Galaxies”, Pogge, Richard W., & Eskridge, Paul B. 1987, AJ, 93, 291 5. “FY Aquilae and the Gamma-Ray Burst Event of 1979 March 31”, Hartmann, Dieter, & Pogge, Richard W. 1987, ApJ, 318, 363 6. “Optical Spectra of Narrow Emission Line Palomar-Green Galaxies”, Osterbrock, Donald E., & Pogge, Richard W. 1987, ApJ, 323, 108 7. “The circumnuclear environment of the nearby non-interacting Seyfert galaxies NGC 5273 and NGC 3516”, Pogge, R. W., 1988, LNP, 307, 46 8. “An Extended Ionizing Radiation Cone from the Nucleus of the Seyfert 2 Galaxy NGC 1068”, Pogge, Richard W. 1988, ApJ, 328, 519 9. “Extended Ionized Gas in the Seyfert 2 Galaxy NGC 4388”, Pogge, Richard W. 1988, ApJ, 332, 702 10. “OTS 1809+314 and the Gamma-Ray Burst GB 790325b”, Hartmann, Dieter, Pogge, Richard W., Hurley, Kevin, Vrba, Frederick J., & Jennings, Mark C. -
Arxiv:0712.4313V1
Nuclear/Circumnuclear Starbursts and Active Galactic Nuclei Mass Accretion in Seyfert Galaxies Yasuyuki Watabe1,2,∗, Nozomu Kawakatu3 and Masatoshi Imanishi3 1Center for Computational Sciences, University of Tsukuba, Ten-nodai, 1-1-1 Tsukuba, Ibaraki 305-8577, Japan; [email protected] 2INAF-Osservatorio Astrofisico di Arcetri, Largo Enrico Fermi 5, 50125 Firenze, Italy 3National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588, Japan ABSTRACT We investigated the correlation between nuclear/circumnuclear starbursts around the active galactic nuclei (AGNs) and the AGN activities for 43 Seyfert galaxies in the CfA and 12 µm samples. We found that circumnuclear starburst luminosity as well as nuclear starburst luminosity are positively correlated with AGN luminosity. Moreover, nuclear starburst luminosity is more strongly cor- related with the AGN luminosity normalized with AGN Eddington luminosity than is circumnuclear starburst luminosity. This implies that starbursts nearer the AGN could have a greater effect on AGN mass accretion. We also discuss these results from the viewpoint of the radiation effects from starbursts and se- quential starbursts. Subject headings: galaxies: active — galaxies: nuclei — galaxies: Seyfert — galaxies: starburst — infrared: galaxies arXiv:0712.4313v1 [astro-ph] 28 Dec 2007 1. INTRODUCTION Since the discovery of active galactic nuclei (AGNs) the physical mechanism of AGN fuel- ing remains unresolved. Various fueling mechanisms have been considered thus far, for exam- ple, tidal torque driven by major/minor galaxy merger (Hernquist 1989; Barnes & Hernquist 1991; Mihos & Hernquist 1996; Taniguchi 1999; Saitoh & Wada 2004), tidal torque from nonaxisymmetric gravitational potential due to a stellar bar (Noguchi 1988; Shlosman et al. -
Star Formation and Nuclear Activity of Local Luminous Infrared Galaxies
PhD Thesis Star Formation and Nuclear Activity of Local Luminous Infrared Galaxies Memoria de tesis doctoral presentada por D. Miguel Pereira Santaella para optar al grado de Doctor en Ciencias F´ısicas Universidad Aut´onoma Consejo Superior de Madrid de Investigaciones Cient´ıficas Facultad de Ciencias Instituto de Estructura de la Materia Departamento de F´ısica Te´orica Centro de Astrobiolog´ıa Madrid, noviembre de 2011 Directora: Dra. Almudena Alonso Herrero Instituto de F´ısica de Cantabria Tutora: Prof.ª Rosa Dom´ınguez Tenreiro Universidad Aut´onoma de Madrid Agradecimientos En primer lugar quer´ıadar las gracias a mi directora de tesis, Almudena Alonso Herrero, por haber confiado en mi desde un principio para realizar este trabajo, as´ı como por todo su inter´es y dedicaci´on durante estos cuatro a˜nos. Adem´as me gustar´ıa agradecer la ayuda y consejos de Luis Colina. En este tiempo he tenido la oportunidad de realizar estancias en centros de in- vestigaci´on extranjeros de los que guardo un grato recuerdo personal y cient´ıfico. En particular me gustar´ıaagradecer a George Rieke y a Martin Ward su hospitalidad y amabilidad durante mis visitas al Steward Observatory en la Universidad de Arizona y a la Universidad de Durham. Y volviendo a Madrid, quisiera agradecer a Tanio y a Marce el apoyo y la ayuda que me ofrecieron en los inciertos comienzos de este proyecto. Tambi´en quiero dar las gra- cias a todos (Arancha, Nuria, Alvaro,´ Alejandro, Julia, Jairo, Javier, Ruym´an, Fabi´an, entre otros) por las interesantes conversaciones, a veces incluso sobre ciencia, en las sobremesas, caf´es, etc. -
A Comprehensive Field Guide to the Ngc Volume 1: Autumn/Winter (Andromeda-Eridanus)
A COMPREHENSIVE FIELD GUIDE TO THE NGC VOLUME 1: AUTUMN/WINTER (ANDROMEDA-ERIDANUS) BHAVESH JIVAN-KALA PAREKH A COMPREHENSIVE FIELD GUIDE TO THE NGC VOLUME 2: AUTUMN/WINTER (FORNAX-VOLANS) BHAVESH JIVAN-KALA PAREKH A COMPREHENSIVE FIELD GUIDE TO THE NGC VOLUME 3: SPRING/SUMMER (ANTILA-INDUS) BHAVESH JIVAN-KALA PAREKH A COMPREHENSIVE FIELD GUIDE TO THE NGC VOLUME 4: SPRING/SUMMER (LEO-VULPECULA) BHAVESH JIVAN-KALA PAREKH Front Cover images: Vol 1: NGC 772/ARP 78 Vol 2: NGC 7317-18-19-20 Stephen’s Quintet Vol 3: NGC 4038-39/ARP 244 Antennae Galaxies Vol 4: NGC 5679/ARP 274 Galaxy Triplet Three of the galaxies in this famous grouping, Stephan's Quintet, A beautiful composite image of two colliding galaxies, the A system of three galaxies that appear to be partially overlapping in NGC 772, a spiral galaxy, has much in common with our home are distorted from their gravitational interactions with one another. Antennae galaxies, located about 62 million light-years from Earth. the image, although they may be at somewhat different distances. galaxy, the Milky Way. Each boasts a few satellite galaxies, small One member of the group, NGC 7320 (upper right) is actually The Antennae galaxies take their name from the long antenna-like The spiral shapes of two of these galaxies appear mostly intact. galaxies that closely orbit and are gravitationally bound to their seven times closer to Earth than the rest. "arms," seen in wide-angle views of the system. These features The third galaxy (to the far left) is more compact, but shows were produced by tidal forces generated in the collision, which parent galaxies. -
An Eclipsing Double-Line Spectroscopic Binary at the Stellar/Substellar Boundary in the Upper Scorpius OB Association
A&A 584, A128 (2015) Astronomy DOI: 10.1051/0004-6361/201527464 & c ESO 2015 Astrophysics An eclipsing double-line spectroscopic binary at the stellar/substellar boundary in the Upper Scorpius OB association N. Lodieu1,2, R. Alonso1,2, J. I. González Hernández1,2, R. Sanchis-Ojeda3,, N. Narita4,5,6, Y. Kawashima7, K. Kawauchi8, A. Suárez Mascareño1,2,H.Deeg1,2, J. Prieto Arranz1,2,R.Rebolo1,2, E. Pallé1,2,V.J.S.Béjar1,2, A. Ferragamo1,2, and J. A. Rubiño-Martín1,2 1 Instituto de Astrofísica de Canarias (IAC), Calle Vía Láctea s/n, 38200 La Laguna, Tenerife, Spain e-mail: [email protected] 2 Departamento de Astrofísica, Universidad de La Laguna (ULL), 38206 La Laguna, Tenerife, Spain 3 Department of Astronomy, University of California, Berkeley, CA 94720, USA 4 National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, 181-8588 Tokyo, Japan 5 Astrobiology Center, National Institutes of Natural Sciences, 2-21-1 Osawa, Mitaka, 181-8588 Tokyo, Japan 6 SOKENDAI (The Graduate University for Advanced Studies), Shonan Village, Hayama, 240-0193 Kanagawa, Japan 7 Department of Earth and Planetary Science, The University of Tokyo, 7-3-1 Bunkyo-ku, 113-0033 Tokyo, Japan 8 Department of Earth and Planetary Sciences, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, 152-8551 Tokyo, Japan Received 28 September 2015 / Accepted 9 November 2015 ABSTRACT Aims. We aim at constraining evolutionary models at low mass and young ages by identifying interesting transiting system members of the nearest OB association to the Sun, Upper Scorpius (USco), which has been targeted by the Kepler mission. -
Arxiv:1201.2944V1 [Astro-Ph.HE] 13 Jan 2012 Tde on H Poiersl Ihol Ml Excess Small a Kpc Only Recent with of Other Result at 100S 2009)
Draft version June 26, 2018 A Preprint typeset using LTEX style emulateapj v. 5/2/11 UNDERSTANDING DUAL AGN ACTIVATION IN THE NEARBY UNIVERSE Michael Koss1,2, Richard Mushotzky2, Ezequiel Treister3, Sylvain Veilleux2, Ranjan Vasudevan2, and Margaret Trippe2 Draft version June 26, 2018 ABSTRACT We study the fraction of dual AGN in a sample of 167 nearby (z<0.05), moderate luminosity, ultra hard X-ray selected AGN from the all-sky Swift BAT survey. Combining new Chandra and Gemini observations together with optical and X-ray observations, we find that the dual AGN frequency at scales <100 kpc is ∼10% (16/167). Of the 16 dual AGN, only 3 (19%) were detected using X-ray spectroscopy and were not detected using emission line diagnostics. Close dual AGN (<30 kpc) tend to be more common among the most X-ray luminous systems. In dual AGN, the X-ray luminosity of both AGN increases strongly with decreasing galaxy separation, suggesting that the merging event is key in powering both AGN. 50% of the AGN with a very close companion (<15 kpc), are dual AGN. We also find that dual AGN are more likely to occur in major mergers and tend to avoid absorption line galaxies with elliptical morphologies. Finally, we find SDSS Seyferts are much less likely than BAT AGN (0.25% vs. 7.8%) to be found in dual AGN at scales <30 kpc because of a smaller number of companions galaxies, fiber collision limits, a tendency for AGN at small separations to be detected only in X-rays, and a higher fraction of dual AGN companions with increasing AGN luminosity. -
20110022589.Pdf
Draft version July 6, 2011 A Preprint typeset using LTEX style emulateapj v. 11/10/09 HOST GALAXY PROPERTIES OF THE Swift BAT ULTRA HARD X-RAY SELECTED AGN Michael Koss1,2,3, Richard Mushotzky1, Sylvain Veilleux1, Lisa M. Winter4,5,Wayne Baumgartner2, Jack Tueller2, Neil Gehrels2, and Lynne Valencic2 Draft version July 6, 2011 ABSTRACT We have assembled the largest sample of ultra hard X-ray selected (14-195 keV) AGN with host galaxy optical data to date, with 185 nearby (z<0.05), moderate luminosity AGN from the Swift BAT sample. The BAT AGN host galaxies have intermediate optical colors (u − r and g − r) that are bluer than a comparison sample of inactive galaxies and optically selected AGN from the Sloan Digital Sky Survey (SDSS) which are chosen to have the same stellar mass. Based on morphological classifications from the RC3 and the Galaxy Zoo, the bluer colors of BAT AGN are mainly due to a higher fraction of mergers and massive spirals than in the comparison samples. BAT AGN in massive galaxies (log M∗>10.5) have a 5 to 10 times higher rate of spiral morphologies than in SDSS AGN or inactive galaxies. We also see enhanced far-IR emission in BAT AGN suggestive of higher levels of star formation compared to the comparison samples. BAT AGN are preferentially found in the most massive host galaxies with high concentration indexes indicative of large bulge-to-disk ratios and large supermassive black holes. The narrow-line (NL) BAT AGN have similar intrinsic luminosities as the SDSS NL Seyferts based on measurements of [O III] λ5007.