Curriculum Vitae
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INVESTIGATING ACTIVE GALACTIC NUCLEI with LOW FREQUENCY RADIO OBSERVATIONS By
INVESTIGATING ACTIVE GALACTIC NUCLEI WITH LOW FREQUENCY RADIO OBSERVATIONS by MATTHEW LAZELL A thesis submitted to The University of Birmingham for the degree of DOCTOR OF PHILOSOPHY School of Physics & Astronomy College of Engineering and Physical Sciences The University of Birmingham March 2015 University of Birmingham Research Archive e-theses repository This unpublished thesis/dissertation is copyright of the author and/or third parties. The intellectual property rights of the author or third parties in respect of this work are as defined by The Copyright Designs and Patents Act 1988 or as modified by any successor legislation. Any use made of information contained in this thesis/dissertation must be in accordance with that legislation and must be properly acknowledged. Further distribution or reproduction in any format is prohibited without the permission of the copyright holder. Abstract Low frequency radio astronomy allows us to look at some of the fainter and older synchrotron emission from the relativistic plasma associated with active galactic nuclei in galaxies and clusters. In this thesis, we use the Giant Metrewave Radio Telescope to explore the impact that active galactic nuclei have on their surroundings. We present deep, high quality, 150–610 MHz radio observations for a sample of fifteen predominantly cool-core galaxy clusters. We in- vestigate a selection of these in detail, uncovering interesting radio features and using our multi-frequency data to derive various radio properties. For well-known clusters such as MS0735, our low noise images enable us to see in improved detail the radio lobes working against the intracluster medium, whilst deriving the energies and timescales of this event. -
Constraining Gas Motions in the Intra-Cluster Medium
Noname manuscript No. (will be inserted by the editor) Constraining Gas Motions in the Intra-Cluster Medium Aurora Simionescu · John ZuHone · Irina Zhuravleva · Eugene Churazov · Massimo Gaspari · Daisuke Nagai · Norbert Werner · Elke Roediger · Rebecca Canning · Dominique Eckert · Liyi Gu · Frits Paerels Received: date / Accepted: date Aurora Simionescu SRON, Netherlands Institute for Space Research, Sorbonnelaan 2, 3584 CA Utrecht, The Netherlands; E-mail: [email protected] Institute of Space and Astronautical Science (ISAS), JAXA, 3-1-1 Yoshinodai, Chuo-ku, Sagamihara, Kanagawa, 252-5210, Japan John ZuHone Harvard-Smithsonian Center for Astrophysics, 60 Garden St., Cambridge, MA 02138, USA Irina Zhuravleva Department of Astronomy & Astrophysics, University of Chicago, 5640 S Ellis Ave, Chicago, IL 60637, USA Kavli Institute for Particle Astrophysics and Cosmology, Stanford University, 452 Lomita Mall, Stanford, CA 94305-4085, USA Department of Physics, Stanford University, 382 Via Pueblo Mall, Stanford, CA 94305-4085, USA Eugene Churazov Max Planck Institute for Astrophysics, Karl-Schwarzschild-Strasse 1, D-85741 Garching, Germany Space Research Institute (IKI), Profsoyuznaya 84/32, Moscow 117997, Russia Massimo Gaspari Einstein and Spitzer Fellow, Department of Astrophysical Sciences, Princeton University, 4 Ivy Lane, Princeton, NJ 08544-1001, USA Daisuke Nagai Department of Physics, Yale University, PO Box 208101, New Haven, CT, USA Yale Center for Astronomy and Astrophysics, PO Box 208101, New Haven, CT, USA Norbert Werner MTA-E¨otv¨osLor´andUniversity Lend¨uletHot Universe Research Group, H-1117 P´azm´any P´eters´eta´ny1/A, Budapest, Hungary Department of Theoretical Physics and Astrophysics, Faculty of Science, Masaryk Univer- sity, Kotl´arsk´a2, Brno, 61137, Czech Republic School of Science, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima 739-8526, arXiv:1902.00024v1 [astro-ph.CO] 31 Jan 2019 Japan 2 Aurora Simionescu et al. -
The B3-VLA CSS Sample⋆
A&A 528, A110 (2011) Astronomy DOI: 10.1051/0004-6361/201015379 & c ESO 2011 Astrophysics The B3-VLA CSS sample VIII. New optical identifications from the Sloan Digital Sky Survey The ultraviolet-optical spectral energy distribution of the young radio sources C. Fanti1,R.Fanti1, A. Zanichelli1, D. Dallacasa1,2, and C. Stanghellini1 1 Istituto di Radioastronomia – INAF, via Gobetti 101, 40129 Bologna, Italy e-mail: [email protected] 2 Dipartimento di Astronomia, Università di Bologna, via Ranzani 1, 40127 Bologna, Italy Received 12 July 2010 / Accepted 22 December 2010 ABSTRACT Context. Compact steep-spectrum radio sources and giga-hertz peaked spectrum radio sources (CSS/GPS) are generally considered to be mostly young radio sources. In recent years we studied at many wavelengths a sample of these objects selected from the B3-VLA catalog: the B3-VLA CSS sample. Only ≈60% of the sources were optically identified. Aims. We aim to increase the number of optical identifications and study the properties of the host galaxies of young radio sources. Methods. We cross-correlated the CSS B3-VLA sample with the Sloan Digital Sky Survey (SDSS), DR7, and complemented the SDSS photometry with available GALEX (DR 4/5 and 6) and near-IR data from UKIRT and 2MASS. Results. We obtained new identifications and photometric redshifts for eight faint galaxies and for one quasar and two quasar candi- dates. Overall we have 27 galaxies with SDSS photometry in five bands, for which we derived the ultraviolet-optical spectral energy distribution (UV-O-SED). We extended our investigation to additional CSS/GPS selected from the literature. -
And Ecclesiastical Cosmology
GSJ: VOLUME 6, ISSUE 3, MARCH 2018 101 GSJ: Volume 6, Issue 3, March 2018, Online: ISSN 2320-9186 www.globalscientificjournal.com DEMOLITION HUBBLE'S LAW, BIG BANG THE BASIS OF "MODERN" AND ECCLESIASTICAL COSMOLOGY Author: Weitter Duckss (Slavko Sedic) Zadar Croatia Pусскй Croatian „If two objects are represented by ball bearings and space-time by the stretching of a rubber sheet, the Doppler effect is caused by the rolling of ball bearings over the rubber sheet in order to achieve a particular motion. A cosmological red shift occurs when ball bearings get stuck on the sheet, which is stretched.“ Wikipedia OK, let's check that on our local group of galaxies (the table from my article „Where did the blue spectral shift inside the universe come from?“) galaxies, local groups Redshift km/s Blueshift km/s Sextans B (4.44 ± 0.23 Mly) 300 ± 0 Sextans A 324 ± 2 NGC 3109 403 ± 1 Tucana Dwarf 130 ± ? Leo I 285 ± 2 NGC 6822 -57 ± 2 Andromeda Galaxy -301 ± 1 Leo II (about 690,000 ly) 79 ± 1 Phoenix Dwarf 60 ± 30 SagDIG -79 ± 1 Aquarius Dwarf -141 ± 2 Wolf–Lundmark–Melotte -122 ± 2 Pisces Dwarf -287 ± 0 Antlia Dwarf 362 ± 0 Leo A 0.000067 (z) Pegasus Dwarf Spheroidal -354 ± 3 IC 10 -348 ± 1 NGC 185 -202 ± 3 Canes Venatici I ~ 31 GSJ© 2018 www.globalscientificjournal.com GSJ: VOLUME 6, ISSUE 3, MARCH 2018 102 Andromeda III -351 ± 9 Andromeda II -188 ± 3 Triangulum Galaxy -179 ± 3 Messier 110 -241 ± 3 NGC 147 (2.53 ± 0.11 Mly) -193 ± 3 Small Magellanic Cloud 0.000527 Large Magellanic Cloud - - M32 -200 ± 6 NGC 205 -241 ± 3 IC 1613 -234 ± 1 Carina Dwarf 230 ± 60 Sextans Dwarf 224 ± 2 Ursa Minor Dwarf (200 ± 30 kly) -247 ± 1 Draco Dwarf -292 ± 21 Cassiopeia Dwarf -307 ± 2 Ursa Major II Dwarf - 116 Leo IV 130 Leo V ( 585 kly) 173 Leo T -60 Bootes II -120 Pegasus Dwarf -183 ± 0 Sculptor Dwarf 110 ± 1 Etc. -
Measuring the Scatter in the Cluster Optical Richness-Mass Relation with Machine Learning
MEASURING THE SCATTER IN THE CLUSTER OPTICAL RICHNESS-MASS RELATION WITH MACHINE LEARNING A Dissertation by STEVEN ALVARO BOADA Submitted to the Office of Graduate and Professional Studies of Texas A&M University in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY Chair of Committee, Casey J. Papovich Committee Members, Wolfgang Bangerth Louis Strigari Nicholas Suntzeff Head of Department, Peter McIntyre August 2016 Major Subject: Physics Copyright 2016 Steven Alvaro Boada ABSTRACT The distribution of massive clusters of galaxies depends strongly on the total cos- mic mass density, the mass variance, and the dark energy equation of state. As such, measures of galaxy clusters can provide constraints on these parameters and even test models of gravity, but only if observations of clusters can lead to accurate estimates of their total masses. Here, we carry out a study to investigate the ability of a blind spectroscopic survey to recover accurate galaxy cluster masses through their line- of-sight velocity dispersions (LOSVD) using probability based and machine learning methods. We focus on the Hobby Eberly Telescope Dark Energy Experiment (HET- DEX), which will employ new Visible Integral-Field Replicable Unit Spectrographs (VIRUS), over 420 degree2 on the sky with a 1/4.5 fill factor. VIRUS covers the blue/optical portion of the spectrum (3500 − 5500 A),˚ allowing surveys to measure redshifts for a large sample of galaxies out to z < 0:5 based on their absorption or emission (e.g., [O II], Mg II, Ne V) features. We use a detailed mock galaxy catalog from a semi-analytic model to simulate surveys observed with VIRUS, including: (1) Survey, a blind, HETDEX-like survey with an incomplete but uniform spectroscopic selection function; and (2) Targeted, a survey which targets clusters directly, ob- taining spectra of all galaxies in a VIRUS-sized field. -
Arxiv:1904.13390V3 [Gr-Qc] 14 Jul 2021
July 15, 2021 0:35 WSPC/INSTRUCTION FILE halo˙spacetime International Journal of Modern Physics D © World Scientific Publishing Company Gravitational lensing study of cold dark matter led galactic halo Samrat Ghosh High Energy & Cosmic Ray Research Centre, University of North Bengal, Siliguri, West Bengal, 734013, India [email protected] Arunava Bhadra High Energy & Cosmic Ray Research Centre, University of North Bengal, Siliguri, West Bengal, 734013, India aru [email protected] Amitabha Mukhopadhyay Department of Physics, University of North Bengal, Siliguri, West Bengal, 734013, India amitabha 62@rediffmail.com Received Day Month Year Revised Day Month Year In this work the space-time geometry of the halo region in spiral galaxies is obtained considering the observed flat galactic rotation curve feature, invoking the Tully-Fisher relation and assuming the presence of cold dark matter in the galaxy. The gravitational lensing analysis is performed treating the so obtained space-time as a gravitational lens. It is found that the aforementioned space-time as the gravitational lens can consistently explain the galaxy-galaxy weak gravitational lensing observations and the lensing obser- vations of the well-known Abell 370 and Abell 2390 galaxy clusters. arXiv:1904.13390v3 [gr-qc] 14 Jul 2021 Keywords: galactic rotation curve; galactic halo; gravitational lensing. PACS numbers: 1. Introduction The astrophysical observations reveal that after the termination of the luminous disk the expected Keplerian fall-off is absent in rotation curves (variation of the angular velocity of test particles with distance from the galactic center) of spiral galaxies.58, 63–65, 73 The frequency shift of the 21 cm HI emission line from neutral hydrogen cloud at large distances from the galactic center rotating in circular orbits allows constructing a rotation curve of galaxies involving distances up to a few tens of kpc or even a few hundreds of kpc in few cases. -
The Search for Million Degree Gas Through the NVII Hyperfine Line
The Search for Million Degree Gas Through The N VII Hyperfine Line Joel N. Bregman and Jimmy A. Irwin Department of Astronomy, University of Michigan, Ann Arbor, MI 48109 [email protected], [email protected] ABSTRACT Gas in the million degree range occurs in a variety of astronomical environ- ments, and it may be the main component of the elusive missing baryons at low redshift. The N VII ion is found in this material and it has a hyperfine spin-flip transition with a rest frequency of 53.042 GHz, which can be observed for z > 0.1, when it is shifted into a suitably transparent radio band. We used the 42- 48 GHz spectrometer on the Green Bank Telescope to search for both emission and absorption from this N VII transmission. For absorption studies, 3C273, 3C 279, 3C 345, and 4C+39.25 were observed but no feature were seen above the 5σ level. For emission line studies, we observed Abell 1835, Abell 2390 and the star-forming galaxy PKS 1345+12, but no features were seen exceeding 5σ. We examine whether the strongest emission feature, in Abell 2390 (3.7σ), and the strongest absorption feature, toward 4C+39.25 (3.8σ), might be expected from 10 6 theoretical models. The emission feature would require ∼10 M⊙ of 10 K gas, which is inconsistent with X-ray limits for the O VII Kα line, so it is unlikely to be real. The N VII absorption feature requires a N VII column of 6×1016 cm−2, higher than model predictions by at least an order of magnitude, which makes it inconsistent with model expectations. -
7.5 X 11.5.Doubleline.P65
Cambridge University Press 978-0-521-75618-1 - High Energy Astrophysics, Third Edition Malcolm S. Longair Index More information Name index Abell, George, 99, 101 Cappelluti, Nico, 729 Abraham, Robert, 733 Carter, Brandon, 434 Abramovitz, Milton, 206, 209 Caswell, James, 226 Adams, Fred, 353, 369 Cavaliere, Alfonso, 110 Amsler, Claude, 275 Cesarsky, Catherine, 187, 189 Anderson, Carl, 29, 30, 163 Challinor, Anthony, 115, 259 Arnaud, Monique, 110 Chandrasekhar, Subrahmanyan, 302, 429, 434, Arnett, David, 386 455 Arzoumanian, Zaven, 420 Charlot, Stephane,´ 729, 730, 747 Auger, Pierre, 29 Chwolson, O., 117 Cimatti, Andrea, 736, 748 Babbedge, T., 740 Clayton, Donald, 386 Backer, Donald, 417, 418 Clemmow, Phillip, 267 Bahcall, John, 55, 57, 58 Colless, Matthew, 108, 109 Bahcall, Neta, 105 Compton, Arthur, 231 Balbus, Steven, 455 Cordes, James, 420 Band, David, 264 Cowie, Lennox, 733, 736, 743, 745 Barger, Amy, 745 Cox, Donald, 357 Beckwith, Steven, 737, 744 Becquerel, Henri, 146 Damon, Paul, 297 Bekefi, George, 193 Davies, Rodney, 376 Bell(-Burnell), Jocelyn, 19, 406 Davis, Leverett, 373 Bennett, Charles, 16 Davis, Raymond, 32, 54, 55 Bethe, Hans, 57, 163, 166, 175 de Vaucouleurs, Gerard,´ 77, 78 Bignami, Giovanni, 197 Dermer, Charles, 505 Binney, James, 106, 153 Deubner, Franz-Ludwig, 51 Blaauw, Adriaan, 754 Diehl, Roland, 287 Blackett, Patrick, 29 Dirac, Adrian, 29 Blain, Andrew, 743 Djorgovski, George, 88 Bland-Hawthorn, Jonathan, 733 Dougherty, John, 267 Blandford, Roger, 251 Draine, Bruce, 351, 372, 373, 375, Blumenthal, George, 163, 175, -
An ISOCAM Survey Through Gravitationally Lensing Galaxy Clusters
A&A 431, 433–449 (2005) Astronomy DOI: 10.1051/0004-6361:20041782 & c ESO 2005 Astrophysics An ISOCAM survey through gravitationally lensing galaxy clusters IV. Luminous infrared galaxies in Cl 0024+1654 and the dynamical status of clusters D. Coia1, B. McBreen1,L.Metcalfe2,3,A.Biviano4, B. Altieri2,S.Ott5,B.Fort6,J.-P.Kneib7,8, Y. Mellier6,9, M.-A. Miville-Deschênes10 , B. O’Halloran1,11, and C. Sanchez-Fernandez2 1 Department of Experimental Physics, University College, Belfield, Dublin 4, Ireland e-mail: [email protected] 2 XMM-Newton Science Operations Centre, European Space Agency, Villafranca del Castillo, PO Box 50727, 28080 Madrid, Spain 3 ISO Data Centre, European Space Agency, Villafranca del Castillo, PO Box 50727, 28080 Madrid, Spain 4 INAF/Osservatorio Astronomico di Trieste, via G.B. Tiepolo 11, 34131, Trieste, Italy 5 Science Operations and Data Systems Division of ESA, ESTEC, Keplerlaan 1, 2200 AG Noordwijk, The Netherlands 6 Institut d’Astrophysique de Paris, 98 bis boulevard Arago, 75014 Paris, France 7 Observatoire Midi-Pyrénées, 14 avenue Edouard Belin, 31400 Toulouse, France 8 California Institute of Technology, Pasadena, CA 91125, USA 9 Observatoire de Paris, 61 avenue de l’Observatoire, 75014 Paris, France 10 Canadian Institute for Theoretical Astrophysics, 60 St-George Street, Toronto, Ontario M5S 3H8, Canada 11 Dunsink Observatory, Castleknock, Dublin 15, Ireland Received 3 August 2004 / Accepted 26 October 2004 Abstract. Observations of the core of the massive cluster Cl 0024+1654, at a redshift z ∼ 0.39, were obtained with the Infrared Space Observatory using ISOCAM at 6.7 µm (hereafter 7 µm) and 14.3 µm (hereafter 15 µm). -
Locuss: the MID-INFRARED BUTCHER–OEMLER EFFECT
The Astrophysical Journal, 704:126–136, 2009 October 10 doi:10.1088/0004-637X/704/1/126 C 2009. The American Astronomical Society. All rights reserved. Printed in the U.S.A. LoCuSS: THE MID-INFRARED BUTCHER–OEMLER EFFECT C. P. Haines1,G.P.Smith1,E.Egami2,R.S.Ellis3,4, S. M. Moran5, A. J. R. Sanderson1, P. Merluzzi6, G. Busarello6, andR.J.Smith7 1 School of Physics and Astronomy, University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK; [email protected] 2 Steward Observatory, University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721, USA 3 California Institute of Technology, 105-24 Astronomy, Pasadena, CA 91125, USA 4 Department of Astrophysics, University of Oxford, Keble Road, Oxford, OX1 3RH, UK 5 Department of Physics and Astronomy, The Johns Hopkins University, 3400 N. Charles Street, Baltimore, MD 21218, USA 6 INAF - Osservatorio Astronomico di Capodimonte, via Moiariello 16, I-80131 Napoli, Italy 7 Department of Physics, Durham University, Durham, DH1 3LE, UK Received 2009 March 28; accepted 2009 August 14; published 2009 September 21 ABSTRACT We study the mid-infrared (MIR) properties of galaxies in 30 massive galaxy clusters at 0.02 z 0.40, using panoramic Spitzer/MIPS 24 μm and near-infrared data, including 27 new observations from the LoCuSS and ACCESS surveys. This is the largest sample of clusters to date with such high-quality and uniform MIR data covering not only the cluster cores, but extending into the infall regions. We use these data to revisit the so- called Butcher–Oemler (BO) effect, measuring the fraction of massive infrared luminous galaxies (K<K+1.5, 10 LIR > 5×10 L) within r200, finding a steady increase in the fraction with redshift from ∼3% at z = 0.02 to ∼10% by z = 0.30, and an rms cluster-to-cluster scatter about this trend of 0.03. -
Arxiv:1707.07134V1 [Astro-Ph.GA] 22 Jul 2017 2 Radio-Selected AGN
Astronomy Astrophysics Review manuscript No. (will be inserted by the editor) Active Galactic Nuclei: what’s in a name? P. Padovani · D. M. Alexander · R. J. Assef · B. De Marco · P. Giommi · R. C. Hickox · G. T. Richards · V. Smolciˇ c´ · E. Hatziminaoglou · V. Mainieri · M. Salvato Received: June 12, 2017 / Accepted: July 21, 2017 Abstract Active Galactic Nuclei (AGN) are energetic as- sic differences between AGN, and primarily reflect varia- trophysical sources powered by accretion onto supermassive tions in a relatively small number of astrophysical parame- black holes in galaxies, and present unique observational ters as well the method by which each class of AGN is se- signatures that cover the full electromagnetic spectrum over lected. Taken together, observations in different electromag- more than twenty orders of magnitude in frequency. The netic bands as well as variations over time provide comple- rich phenomenology of AGN has resulted in a large number mentary windows on the physics of different sub-structures of different “flavours” in the literature that now comprise a in the AGN. In this review, we present an overview of AGN complex and confusing AGN “zoo”. It is increasingly clear multi-wavelength properties with the aim of painting their that these classifications are only partially related to intrin- “big picture” through observations in each electromagnetic band from radio to γ-rays as well as AGN variability. We P. Padovani · E. Hatziminaoglou · V. Mainieri address what we can learn from each observational method, European Southern Observatory, Karl-Schwarzschild-Str. 2, D-85748 the impact of selection effects, the physics behind the emis- Garching bei Munchen,¨ Germany sion at each wavelength, and the potential for future studies. -
Arxiv:Astro-Ph/9907379V1 27 Jul 1999
A subarcsecond resolution near-infrared study of Seyfert and ‘normal’ galaxies: II. Morphology Johan H. Knapen1 Isaac Shlosman2 Reynier F. Peletier3,4 1Department of Physical Sciences, University of Hertfordshire, Hatfield, Herts AL10 9AB, UK, E-mail: [email protected] 2 Department of Physics & Astronomy, University of Kentucky, Lexington, KY 40506-0055, USA, E-mail: [email protected] 3Dept. of Physics, University of Durham, South Road, Durham, DH1 3LE, UK 4School of Physics and Astronomy, University of Nottingham, Nottingham, NG7 2RD, UK, E-mail: [email protected] ABSTRACT We present a detailed study of the bar fraction in the CfA sample of Seyfert galaxies, and in a carefully selected control sample of non-active galaxies, to investigate the rela- tion between the presence of bars and of nuclear activity. To avoid the problems related to bar classification in the RC3, e.g., subjectivity, low resolution and contamination by dust, we have developed an objective bar classification method, which we conservatively apply to our new sub-arcsecond resolution near-infrared imaging data set (Peletier et al. 1999). We are able to use stringent criteria based on radial profiles of ellipticity and major axis position angle to determine the presence of a bar and its axial ratio. Concen- arXiv:astro-ph/9907379v1 27 Jul 1999 trating on non-interacting galaxies in our sample for which morphological information can be obtained, we find that Seyfert hosts are barred more often (79%±7.5%) than the non-active galaxies in our control sample (59%±9%), a result which is at the ∼ 2.5σ significance level.