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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Sciences The University of Birmingham March 2015 University of Birmingham Research Archive e-theses repository This unpublished thesis/dissertation is copyright of the author and/or third parties.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. -
GMRT 610 Mhz Observations of Galaxy Clusters in the ACT Equatorial Sample
MNRAS 000,1{26 (2018) Preprint 20 March 2019 Compiled using MNRAS LATEX style file v3.0 GMRT 610 MHz observations of galaxy clusters in the ACT equatorial sample Kenda Knowles,1? Andrew J. Baker,2 J. Richard Bond,3 Patricio A. Gallardo,4 Neeraj Gupta,5 Matt Hilton,1 John P. Hughes,2 Huib Intema,6 Carlos H. L´opez- Caraballo,7;8 Kavilan Moodley,1 Benjamin L. Schmitt,9 Jonathan Sievers,10 Crist´obal Sif´on,4;11 Edward Wollack,12 1Astrophysics & Cosmology Research Unit, School of Mathematics, Statistics & Computer Science, University of KwaZulu-Natal, Durban, 3690, South Africa 2Department of Physics and Astronomy, Rutgers, The State University of New Jersey, 136 Frelinghuysen Road, Piscataway, NJ 08854-8019, USA 3Canadian Institute for Theoretical Astrophysics, 60 St. George Street, University of Toronto, Toronto, ON, M5S 3H8, Canada 4Department of Physics, Cornell University, Ithaca, NY USA 5IUCAA, Post Bag 4, Ganeshkhind, Pune 411007, India 6Leiden Observatory, Leiden University, PO Box 9513, NL2300 RA Leiden, Netherlands 7Instituto de Astrof´ısica and Centro de Astro-Ingenier´ıa, Facultad de F´ısica, Pontificia Universidad Cat´olica de Chile, Av. Vicu~na Mackenna 4860, 7820436 Macul, Santiago, Chile 8Departamento de Matem´aticas, Universidad de La Serena, Av. Juan Cisternas 1200, La Serena, Chile 9Department of Physics and Astronomy, University of Pennsylvania, 209 South 33rd Street, Philadelphia, PA 19104, USA 10Astrophysics & Cosmology Research Unit, School of Chemistry & Physics, University of KwaZulu-Natal, Durban, 3690, South Africa 11Department of Astrophysical Sciences, Peyton Hall, Princeton University, Princeton, NJ 08544, USA 12NASA/Goddard Space Flight Center, 8800 Greenbelt Rd, Greenbelt, MD 20771, USA Accepted XXX. -
16Th HEAD Meeting Session Table of Contents
16th HEAD Meeting Sun Valley, Idaho – August, 2017 Meeting Abstracts Session Table of Contents 99 – Public Talk - Revealing the Hidden, High Energy Sun, 204 – Mid-Career Prize Talk - X-ray Winds from Black Rachel Osten Holes, Jon Miller 100 – Solar/Stellar Compact I 205 – ISM & Galaxies 101 – AGN in Dwarf Galaxies 206 – First Results from NICER: X-ray Astrophysics from 102 – High-Energy and Multiwavelength Polarimetry: the International Space Station Current Status and New Frontiers 300 – Black Holes Across the Mass Spectrum 103 – Missions & Instruments Poster Session 301 – The Future of Spectral-Timing of Compact Objects 104 – First Results from NICER: X-ray Astrophysics from 302 – Synergies with the Millihertz Gravitational Wave the International Space Station Poster Session Universe 105 – Galaxy Clusters and Cosmology Poster Session 303 – Dissertation Prize Talk - Stellar Death by Black 106 – AGN Poster Session Hole: How Tidal Disruption Events Unveil the High 107 – ISM & Galaxies Poster Session Energy Universe, Eric Coughlin 108 – Stellar Compact Poster Session 304 – Missions & Instruments 109 – Black Holes, Neutron Stars and ULX Sources Poster 305 – SNR/GRB/Gravitational Waves Session 306 – Cosmic Ray Feedback: From Supernova Remnants 110 – Supernovae and Particle Acceleration Poster Session to Galaxy Clusters 111 – Electromagnetic & Gravitational Transients Poster 307 – Diagnosing Astrophysics of Collisional Plasmas - A Session Joint HEAD/LAD Session 112 – Physics of Hot Plasmas Poster Session 400 – Solar/Stellar Compact II 113 -
Where Are the Missing Baryons in Clusters?
1 Where Are the Missing Baryons in Clusters? Bilhuda Rasheed Adviser: Dr. Neta Bahcall Submitted in partial fulfillment of the requirements for the degree of Bachelor of Arts Department of Astrophysical Sciences Princeton University May 2010 I hereby declare that I am the sole author of this thesis. I authorize Princeton University to lend this thesis to other institutions or individuals for the purpose of scholarly research. Bilhuda Rasheed I further authorize Princeton University to reproduce this thesis by photocopying or by other means, in total or in part, at the request of other institutions or individuals for the purpose of scholarly research. Bilhuda Rasheed Abstract We address previous claims that the baryon fraction in clusters is significantly below the cosmic value of the baryon fraction as determined from WMAP 7-year results. We use X-ray and SZ observations to determine the slope of the gas density profile to R200. This is shallower than the slope of total mass density (NFW) profile. We use the gas density slope to extrapolate the X-ray observations of gas fraction at R500 to the virial radius (R100). The gas fraction increases beyond R500 for all cluster masses. We add the stellar fraction as determined from COSMOS and 2MASS samples, with ICL contributing 10% to the stellar fraction. For massive clusters 14 (M500 ∼ 7 × 10 M ), the baryon fraction reaches the cosmic baryon fraction at Rvir± 20%. Poorer clusters and groups typically reach 75–85% of the cosmic baryon fraction at the virial radius. We compare these results with simulations which take into account gravitational shock-heating, star formation, heating from SNe and AGN, and energy transfer from dark matter. -
MASS and LIGHT of ABELL 370: a STRONG and WEAK LENSING ANALYSIS ABSTRACT We Present a New Gravitational Lens Model of the Hubble
Draft version October 15, 2018 Preprint typeset using LATEX style emulateapj v. 01/23/15 MASS AND LIGHT OF ABELL 370: A STRONG AND WEAK LENSING ANALYSIS V. Strait1, M. Bradacˇ1, A. Hoag1, K.-H. Huang1, T. Treu2, X. Wang2,4, R. Amorin6,7, M. Castellano5, A. Fontana5, B.-C. Lemaux1, E. Merlin5, K.B. Schmidt3, T. Schrabback8, A. Tomczack1, M. Trenti9,10, and B. Vulcani9,11 1Physics Department, University of California, Davis, CA 95616, USA 2Department of Physics and Astronomy, UCLA, Los Angeles, CA, 90095-1547, USA 3Leibniz-Institut f¨urAstrophysik Postdam (AIP), An der Sternwarte 16, 14482 Potsdam, Germany 4Department of Physics, University of California, Santa Barbara, CA, 93106-9530, USA 5INAF - Osservatorio Astronomico di Roma Via Frascati 33 - 00040 Monte Porzio Catone, 00040 Rome, Italy 6Cavendish Laboratory, University of Cambridge, 19 JJ Thomson Avenue, CB3 0HE, Cambridge, UK 7Kavli Institute for Cosmology, University of Cambridge, Madingley Rd., CB3 0HA, Cambridge, UK 8Argelander-Institut f¨urAstronomie, Auf dem H¨ugel71, D-53121 Bonn, Germany 9School of Physics, University of Melbourne, Parkville, Victoria, Australia 10ARC Centre of Excellence fot All Sky Astrophysics in 3 Dimensions (ASTRO 3D) and 11INAF - Astronomical Observatory of Padora, 35122 Padova, Italy Draft version October 15, 2018 ABSTRACT We present a new gravitational lens model of the Hubble Frontier Fields cluster Abell 370 (z = 0:375) using imaging and spectroscopy from Hubble Space Telescope and ground-based spectroscopy. We combine constraints from a catalog of 909 weakly lensed galaxies and 39 multiply-imaged sources comprised of 114 multiple images, including a system of multiply-imaged candidates at z = 7:84 ± 0:02, to obtain a best-fit mass distribution using the cluster lens modeling code Strong and Weak Lensing United. -
List of Reserved Targets Sent to GRANTECAN for the Exploitation of the MEGARA Guaranteed Time at GTC
List of Reserved Targets sent to GRANTECAN for the exploitation of the MEGARA Guaranteed Time at GTC List of Reserved Targets sent to GRANTECAN for the exploitation of the MEGARA Guaranteed Time at GTC List of Reserved Targets sent to GRANTECAN for the exploitation of the MEGARA Guaranteed Time at GTC INDEX 1. MEGADES – MEGARA GALAXY DISKS EVOLUTION SURVEY: S4G .................. 3 2. MEGADES – MEGARA GALAXY DISKS EVOLUTION SURVEY: M33 ............... 11 3. SPECTROSCOPIC STUDY OF COMPACT STELLAR CLUSTERS AND THEIR SURROUNDINGS IN NEARBY GALAXIES ........................................................................ 12 4. THE CHEMICAL COMPOSITION OF PHOTOIONIZED NEBULAE¡ERROR! MARCADOR NO DEFINIDO. 5. CHROMOSPHERIC ACTIVITY AND AGE OF SOLAR ANALOGS IN OPEN CLUSTERS ................................................................ ¡ERROR! MARCADOR NO DEFINIDO. 6. STUDY OF STELLAR POPULATIONS AND GAS PROPERTIES IN STAR FORMING GALAXIES ............................................................................................................ 14 7. DISSECTING Z∼2-3 HEII-EMITTERS: SPECTRAL TEMPLATES FOR THE SOURCES OF THE COSMIC DAWN ................................................................................... 16 8. CHEMODYNAMICS OF METAL-POOR EXTREME EMISSION LINE GALAXIES AT INTERMEDIATE Z ...................................................................................... 18 9. CONSTRAINING WOLF-RAYET STARS IN EXTREMELY METAL-POOR GALAXIES ................................................................................................................................ -
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. -
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). -
The Legacy of Einstein's Eclipse, Gravitational Lensing
The Legacy of Einstein’s Eclipse, Gravitational Lensing Jorge L. Cervantes-Cota 1, Salvador Galindo-Uribarri 1 and George F. Smoot 2,3,4,* 1 Department of Physics, National Institute for Nuclear Research, Km 36.5 Carretera Mexico-Toluca, Ocoyoacac, C.P.52750 Mexico State, Mexico; [email protected] (J.L.C.-C.); [email protected] (S.G.-U.) 2 IAS TT & WF Chao Foundation Professor, Institute for Advanced Study, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong 3 Université Sorbonne Paris Cité, Laboratoire APC-PCCP, Université Paris Diderot, 10 rue Alice Domon et Leonie Duquet, CEDEX 13, 75205 Paris, France 4 Department of Physics and LBNL, University of California, MS Bldg 50-5505 LBNL, 1 Cyclotron Road, Berkeley, CA 94720, USA * Correspondence: [email protected]; Tel.: +1-510-486-5505 Abstract: A hundred years ago, two British expeditions measured the deflection of starlight by the Sun’s gravitational field, confirming the prediction made by Einstein’s General Theory of Relativity. One hundred years later many physicists around the world are involved in studying the consequences and use as a research tool, of the deflection of light by gravitational fields, a discipline that today receives the generic name of Gravitational Lensing. The present review aims to commemorate the centenary of Einstein’s Eclipse expeditions by presenting a historical perspective of the development and milestones on gravitational light bending, covering from early XIX century speculations, to its current use as an important research tool in astronomy and cosmology. Keywords: gravitational lensing; history of science PACS: 01.65.+g; 98.62.Sb 1. -
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. -
Hubble Space Telescope
Hubble Space Telescope Tom Brown STUC Meeting – October 20, 2016 • All science instruments and subsystems are funconing well – Decision made to stay in 3-gyro mode Summary as long as possible (3-3-3-1-1) – Instrument teams busy with standard support and calibraon but looking for improvements and expanded capabilies • Cycle 24 – TAC met 5-10 June, noficaons 24 June – Phase II & budget deadline was 21 July – Cycle 24 officially began on 1 October – Exoplanet & Juno programs prominent • Observing efficiency remains excellent – C23 avg 85 orbits/week and 51% efficiency – New “schedule gap” pilot program execung • HST Contract Extension – 1 July 2016 to 30 June 2021 – Senior Review feedback very posive Frontier Fields Completed Abell 2744 MACSJ0416.1-2403 MACSJ0717.5+3745 MACSJ1149.5+2223 Abell S1063 Abell 370 Frontier Fields Completed Abell 2744-par MACSJ0416.1-2403-par MACSJ0717.5+3745-par MACSJ1149.5+2223-par Abell S1063-par Abell 370-par Frontier Fields Completed Last two fields (Abell S1063, Abell 370) completed 11 Sep 2016 V1.0 high-level HST data products released for all but Abell 370 epoch 2 V0.5 Abell 370 epoch 2 – 3 Oct 2016 V1.0 Abell 370 epoch 2 - by 31 Oct 2016 V2.0 for all clusters - by 15 Dec 2016 Lensing models done for 2 clusters. Next 2 in Feb 2017, then last 2 in Sep 2017. Hubble Science Productivity Remains High Recent Safing Events • STIS suspended on 19 June 2016 while passing through the South Atlantic Anomaly – Consistent with Single Event Upset – Recovered 21 June 2016 with no issues • HST payload safed due to lockup of Science