International Evaluation of Onsala Space Observatory
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RF Interference Monitoring for the Onsala Space Observatory Master of Science Thesis (Communication Engineering)
RF Interference Monitoring for the Onsala Space Observatory Master of Science Thesis (Communication Engineering) SYED AMEER AHMED GILLANI Department of Earth and Space Sciences, Onsala Space Observatory, CHALMERS UNIVERSITY OF TECHNOLOGY, Göteborg, Sweden, 2010. RF INTERFERENCE MONITORING FOR ONSALA SPACE OBSERVATORY SYED AMEER AHMED GILLANI Department of Earth and Space Sciences, Onsala Space Observatory CHALMERS UNIVERSITY OF TECHNOLOGY Göteborg, Sweden 2010 ii ABSTRACT With the continuous and rapid developments in wireless services and allocation of radio frequency spectrum to these services, huge interferences have been observed in the field of radio astronomy. According to the international regulations, parts of the spectra are reserved for radio-astronomical observations. Man-made signals entering the receiver chain of a radio telescope have much higher power compared to natural or passive signals received at the radio telescopes. Passive signals received at radio telescopes are normally 60 dB below the receiver noise level. Active signals generated by man-made wireless services pollute the natural emissions by completely masking them due to high signal strength. The cosmic radiation is determined by the fundamental laws of physics, thus the frequencies are fixed and cannot be changed. So interferences created by active services lead to wrong interpretations of the astronomical data. The present thesis deals with RF interference monitoring system for the Onsala Space Observatory. As part of the thesis, a software application has been developed, which communicates with different type of digital receivers (spectrum analyzers) attached with antenna controlling hardware to control omnidirectional and steerable antennas. A steerable antenna is used to find the direction of interference source by moving the antenna in azimuth and elevation direction. -
Cutting-Edge Engineering for the World's Largest Radio Telescope
SKAO Cutting-edge engineering for the world’s largest radio telescope Cutting-edge engineering for the world’s largest radio telescope Approaching a technological challenge on the scale of the SKA is formidable... while building on 60 years of radio- astronomy developments, the huge increase in scale from existing facilities demands a revolutionary break from traditional radio telescope design and radical developments in processing, computer speeds and the supporting technological infrastructure. To answer this challenge the SKA has been broken down into various elements that will form the final SKA telescope. Each element is managed by an international consortium comprising world leading experts in their fields. The SKA Office, staffed with engineering domain experts, systems engineers, scientists and managers, centralises the project management and system design. SKAO The design work was awarded through the SKA Office to these Consortia, made up of over 100 of some of the world’s top research institutions and companies, drawn primarily from the SKA Member countries but also beyond. Following the delivery of a detailed design package in 2016, in 2018 nine consortia are having their Critical Design Reviews (CDR) to deliver the final design documentation to prepare a construction proposal for government approval. The other three consortia are part of the SKA’s Advanced Instrumentation Programme, which develops future instrumention for the SKA. The 2018 SKA CalenDaR aims to recognise the immense work conducted by these hundreds of dedicated engineers and project managers from around the world over the past five years. Without their crucial work, the SKA’s ambitious science programme would not be possible. -
Event Horizon Telescope Observations of the Jet Launching and Collimation in Centaurus A
https://doi.org/10.1038/s41550-021-01417-w Supplementary information Event Horizon Telescope observations of the jet launching and collimation in Centaurus A In the format provided by the authors and unedited Draft version May 26, 2021 Typeset using LATEX preprint style in AASTeX63 Event Horizon Telescope observations of the jet launching and collimation in Centaurus A: Supplementary Information Michael Janssen ,1, 2 Heino Falcke ,2 Matthias Kadler ,3 Eduardo Ros ,1 Maciek Wielgus ,4, 5 Kazunori Akiyama ,6, 7, 4 Mislav Balokovic´ ,8, 9 Lindy Blackburn ,4, 5 Katherine L. Bouman ,4, 5, 10 Andrew Chael ,11, 12 Chi-kwan Chan ,13, 14 Koushik Chatterjee ,15 Jordy Davelaar ,16, 17, 2 Philip G. Edwards ,18 Christian M. Fromm,4, 5, 19 Jose´ L. Gomez´ ,20 Ciriaco Goddi ,2, 21 Sara Issaoun ,2 Michael D. Johnson ,4, 5 Junhan Kim ,13, 10 Jun Yi Koay ,22 Thomas P. Krichbaum ,1 Jun Liu (刘Ê ) ,1 Elisabetta Liuzzo ,23 Sera Markoff ,15, 24 Alex Markowitz,25 Daniel P. Marrone ,13 Yosuke Mizuno ,26, 19 Cornelia Muller¨ ,1, 2 Chunchong Ni ,27, 28 Dominic W. Pesce ,4, 5 Venkatessh Ramakrishnan ,29 Freek Roelofs ,5, 2 Kazi L. J. Rygl ,23 Ilse van Bemmel ,30 Antxon Alberdi ,20 Walter Alef,1 Juan Carlos Algaba ,31 Richard Anantua ,4, 5, 17 Keiichi Asada,22 Rebecca Azulay ,32, 33, 1 Anne-Kathrin Baczko ,1 David Ball,13 John Barrett ,6 Bradford A. Benson ,34, 35 Dan Bintley,36 Raymond Blundell ,5 Wilfred Boland,37 Geoffrey C. Bower ,38 Hope Boyce ,39, 40 Michael Bremer,41 Christiaan D. -
EVN Biennial Report Pages Web
EVN Biennial Report 2015- 2016 Cover Page Credit: Image by Paul Boven ([email protected]). Sateltite Image: Blue marble Next Generation, courtesy of NASA Visible Earth 2 FOREWORD FROM THE EVN CONSORTIUM BOARD OF DIRECTORS CHAIRPERSON 3 THE EVN 6 THE EUROPEAN CONSORTIUM FOR VLBI 6 EVN PROGRAM COMMITTEE 8 EVN PC MEETINGS 9 PROPOSAL STATISTICS 9 REQUESTED SCIENCE RESEARCH AREAS AND OBSERVING BANDS 10 EVN SCHEDULER REPORT 13 TECHNICAL AND OPERATIONS GROUP REPORT 19 EVN OBSERVATORY REPORTS 22 ASTRON - WESTERBORK SYNTHESIS RADIO TELESCOPE 22 HARTEBEESTHOEK RADIO ASTRONOMY OBSERVATORY 24 INSTITUTE OF RADIO ASTRONOMY (INAF), ITALY 25 MEDICINA STATION 25 NOTO STATION 26 SARDINIA RADIO TELESCOPE 27 INSTITUTE OF APPLIED ASTRONOMY - QUASAR VLBI NETWORK 28 IAA CORRELATOR CENTER 29 JODRELL BANK OBSERVATORY 30 MAX-PLANCK-INSTITUT FUER RADIOASTRONOMIE, BONN 32 EFFELSBERG STATION REPORT 33 BONN CORRELATOR REPORT 35 OBSERVATORIO ASTRONOMICO NACIONAL, IGN - YEBES OBSERVATORY 38 ONSALA SPACE OBSERVATORY 42 SHANGHAI ASTRONOMICAL OBSERVATORY 45 THE TIANMA 65M RADIO TELESCOPE 45 THE SESHAN25 TELESCOPE 46 TORUN CENTRE FOR ASTRONOMY 48 ENGINEERING RESEARCH INSTITUTE ‘VENTSPILS INTERNATIONAL RADIO ASTRONOMY CENTRE’ OF VENTSPILS UNIVERSITY COLLEGE (VIRAC) 50 XINJIANG ASTRONOMICAL OBSERVATORY, NANSHAN STATION 53 ARECIBO - NATIONAL ASTRONOMY & IONOSPHERE CENTER, PUERTO RICO 55 GEODETIC OBSERVATORY WETTZELL, GERMANY 56 KOREA ASTRONOMY & SPACE SCIENCE INSTITUTE - KOREAN VLBI NETWORK 58 METSÄHOVI RADIO OBSERVATORY 60 JOINT INSTITUTE FOR VLBI ERIC REPORT 62 INSTITUTE NEWS -
Table of Contents - 1 - - 2
Table of contents - 1 - - 2 - Table of Contents Foreword 5 1. The European Consortium for VLBI 7 2. Scientific highlights on EVN research 9 3. Network Operations 35 4. VLBI technical developments and EVN operations support at member institutes 47 5. Joint Institute for VLBI in Europe (JIVE) 83 6. EVN meetings 105 7. EVN publications in 2007-2008 109 - 3 - - 4 - Foreword by the Chairman of the Consortium The European VLBI Network (EVN) is the result of a collaboration among most major radio observatories in Europe, China, Puerto Rico and South Africa. The large radio telescopes hosted by these observatories are operated in a coordinated way to perform very high angular observations of cosmic radio sources. The data are then correlated by using the EVN correlator at the Joint Institute for VLBI in Europe (JIVE). The EVN, when operating as a single astronomical instrument, is the most sensitive VLBI array and constitutes one of the major scientific facilities in the world. The EVN also co-observes with the Very Long Baseline Array (VLBA) and other radio telescopes in the U.S., Australia, Japan, Russia, and with stations of the NASA Deep Space Network to form a truly global array. In the past, the EVN also operated jointly with the Japanese space antenna HALCA in the frame of the VLBI Space Observatory Programme (VSOP). The EVN plans now to co-observe with the Japanese space 10-m antenna ASTRO-G, to be launched by 2012, within the frame of the VSOP-2 project. With baselines in excess of 25.000 km, the space VLBI observations provide the highest angular resolution ever achieved in Astronomy. -
NRAO Enews Volume 12, Issue 5 • 13 June 2019
NRAO eNews Volume 12, Issue 5 • 13 June 2019 Upcoming Events NRAO Community Day at UMBC (https://science.nrao.edu/science/meetings/2019/umbc19/index) Jun 13 14, 2019 | Baltimore, MD CASCA 2019 (http://www.physics.mcgill.ca/casca2019/) Jun 17 20, 2019 | Montréal, Québec Radio/mm Astrophysical Frontiers in the Next Decade (http://go.nrao.edu/ngVLA19) Jun 25 27, 2019 | Charlottesville, VA 7th VLA Data Reduction Workshop (http://go.nrao.edu/vladrw) Oct 7 18, 2019 | Socorro, NM ALMA2019: Science Results and CrossFacility Synergies (http://www.eso.org/sci/meetings/2019/ALMA2019Cagliari.html) Oct 14 18, 2019 | Cagliari, Sardinia, Italy Semester 2019B Proposal Outcomes Lewis Ball The NRAO has completed the Semester 2019B proposal review and time allocation process (https://science.nrao.edu/observing/proposal-types/peta) for the Very Large Array (VLA) (https://science.nrao.edu/facilities/evla) and the Very Long Baseline Array (VLBA) (https://science.nrao.edu/facilities/vlba) . For the VLA a single configuration (the D array) will be available in the 19B semester and 124 new proposals were received by the 1 February 2019 submission deadline including one large and sixteen time critical (triggered) proposals. The oversubscription rate (by proposal number) was 2.5 and the proposal pressure (hours requested over hours available) was 2.1, both of which are similar to recent semesters. For the VLBA 27 new proposals were submitted, including two large proposals and one triggered proposal. The oversubscription rate was 2.1 and the proposal pressure was 2.3, both of which are similar to recent semesters. -
The European Vlbi Network: a Sensitive and State-Of- The-Art Instrument for High-Resolution Science
THE EUROPEAN VLBI NETWORK: A SENSITIVE AND STATE-OF- THE-ART INSTRUMENT FOR HIGH-RESOLUTION SCIENCE P. CHARLOT Observatoire de Bordeaux (OASU) – CNRS/UMR 5804 BP 89, 33270 Floirac, France e-mail: [email protected] ABSTRACT. The European VLBI Network (EVN) is an array of 18 radio telescopes located throughout Europe and beyond that carry out synchronized very-long-baseline-interferometric (VLBI) observations of radio-emitting sources. The data are processed at a central facility located at the Joint Institute for VLBI in Europe (JIVE) in the Netherlands. The EVN is freely open to any scientist in the world based on peer-reviewed proposals. This paper outlines the current capabilities of the EVN and procedures for observing, highlights some recent results that have been obtained, and puts emphasis on the future development of the array. 1. INTRODUCTION The European VLBI Network (EVN)1 was formed in 1980 by a consortium of five of the major radio astronomy institutes in Europe (the European Consortium for VLBI). Since then, the EVN and the Consortium has grown to include 12 institutes in Spain, UK, the Netherlands, Germany, Sweden, Italy, Finland, Poland and China (Table 1). In addition, the Hartebeesthoek Radio Astronomy Observatory in South Africa and the Arecibo Observatory in Puerto Rico are active Associate Members of the EVN. The EVN members operate 18 individual antennae, which include some of the world’s largest and most sensitive telescopes (Fig. 1). Together, these telescopes form a large scale facility, a continent-wide radio interferometer with baselines ranging from 200 km to 9000 km. -
Cassiopeia A, Cygnus A, Taurus A, and Virgo a at Ultra-Low Radio Frequencies F
Astronomy & Astrophysics manuscript no. LBAateam c ESO 2020 February 25, 2020 Cassiopeia A, Cygnus A, Taurus A, and Virgo A at ultra-low radio frequencies F. de Gasperin1 J. Vink2;3;4 J.P. McKean5;6 A. Asgekar6;27 M.J. Bentum6;7 R. Blaauw6 A. Bonafede14;15;1 M. Bruggen¨ 1 F. Breitling24 W.N. Brouw5;6 H.R. Butcher26 B. Ciardi28 V. Cuciti1 M. de Vos6 S. Duscha6 J. Eislo¨ffel11 D. Engels1 R.A. Fallows6 T.M.O. Franzen6 M.A. Garrett18;8 A.W. Gunst6 J. Horandel¨ 32;33;34 G. Heald25 L.V.E. Koopmans5 A. Krankowski23 P. Maat6 G. Mann24 M. Mevius6 G. Miley8 A. Nelles21;22 M.J. Norden6 A.R. Offringa6;5 E. Orru´6 H. Paas46 M. Pandey-Pommier30;31 R. Pizzo6 W. Reich35 A. Rowlinson2;6 D.J. Schwarz29 A. Shulevski2 O. Smirnov9;10 M. Soida12 M. Tagger13 M.C. Toribio17 A. van Ardenne6 A.J. van der Horst19;20 M.P. van Haarlem6 R. J. van Weeren8 C. Vocks24 O. Wucknitz35 P. Zarka16 P. Zucca6 (Affiliations can be found after the references) Received ... / Accepted ... Abstract Context. The four persistent radio sources in the northern sky with the highest flux density at metre wavelengths are Cassiopeia A, Cygnus A, Taurus A, and Virgo A; collectively they are called the A-team. Their flux densities at ultra-low frequencies (< 100 MHz) can reach several thousands of janskys, and they often contaminate observations of the low-frequency sky by interfering with image processing. Furthermore, these sources are foreground objects for all-sky observations hampering the study of faint signals, such as the cosmological 21 cm line from the epoch of reionisation. -
LOFAR Detections of Low-Frequency Radio Recombination Lines Towards Cassiopeia A
A&A 551, L11 (2013) Astronomy DOI: 10.1051/0004-6361/201221001 & c ESO 2013 Astrophysics Letter to the Editor LOFAR detections of low-frequency radio recombination lines towards Cassiopeia A A. Asgekar1,J.B.R.Oonk1,S.Yatawatta1,2, R. J. van Weeren3,1,8, J. P. McKean1,G.White4,38, N. Jackson25, J. Anderson32,I.M.Avruch15,2,1, F. Batejat11, R. Beck32,M.E.Bell35,18,M.R.Bell29, I. van Bemmel1,M.J.Bentum1, G. Bernardi2,P.Best7,L.Bîrzan3, A. Bonafede6,R.Braun37, F. Breitling30,R.H.vandeBrink1, J. Broderick18, W. N. Brouw1,2, M. Brüggen6,H.R.Butcher1,9, W. van Cappellen1, B. Ciardi29,J.E.Conway11,F.deGasperin6, E. de Geus1, A. de Jong1,M.deVos1,S.Duscha1,J.Eislöffel28, H. Falcke10,1,R.A.Fallows1, C. Ferrari20, W. Frieswijk1, M. A. Garrett1,3, J.-M. Grießmeier23,36, T. Grit1,A.W.Gunst1, T. E. Hassall18,25, G. Heald1, J. W. T. Hessels1,13,M.Hoeft28, M. Iacobelli3,H.Intema3,31,E.Juette34, A. Karastergiou33 , J. Kohler32, V. I. Kondratiev1,27, M. Kuniyoshi32, G. Kuper1,C.Law24,13, J. van Leeuwen1,13,P.Maat1,G.Macario20,G.Mann30, S. Markoff13, D. McKay-Bukowski4,12,M.Mevius1,2, J. C. A. Miller-Jones5,13 ,J.D.Mol1, R. Morganti1,2, D. D. Mulcahy32, H. Munk1,M.J.Norden1,E.Orru1,10, H. Paas22, M. Pandey-Pommier16,V.N.Pandey1,R.Pizzo1, A. G. Polatidis1,W.Reich32, H. Röttgering3, B. Scheers13,19, A. Schoenmakers1,J.Sluman1,O.Smirnov1,14,17, C. Sobey32, M. Steinmetz30,M.Tagger23,Y.Tang1, C. -
ASTRONET ERTRC Report
Radio Astronomy in Europe: Up to, and beyond, 2025 A report by ASTRONET’s European Radio Telescope Review Committee ! 1!! ! ! ! ERTRC report: Final version – June 2015 ! ! ! ! ! ! 2!! ! ! ! Table of Contents List%of%figures%...................................................................................................................................................%7! List%of%tables%....................................................................................................................................................%8! Chapter%1:%Executive%Summary%...............................................................................................................%10! Chapter%2:%Introduction%.............................................................................................................................%13! 2.1%–%Background%and%method%............................................................................................................%13! 2.2%–%New%horizons%in%radio%astronomy%...........................................................................................%13! 2.3%–%Approach%and%mode%of%operation%...........................................................................................%14! 2.4%–%Organization%of%this%report%........................................................................................................%15! Chapter%3:%Review%of%major%European%radio%telescopes%................................................................%16! 3.1%–%Introduction%...................................................................................................................................%16! -
IERS Annual Report 2012
International Earth Rotation and Reference Systems Service (IERS) Service International de la Rotation de la Terre et des Systèmes de Référence IERS Annual Report 2012 Verlag des Bundesamts für Kartographie und Geodäsie Frankfurt am Main 2014 IERS Annual Report 2012 Edited by Wolfgang R. Dick and Daniela Thaller International Earth Rotation and Reference Systems Service Central Bureau Bundesamt für Kartographie und Geodäsie Richard-Strauss-Allee 11 60598 Frankfurt am Main Germany phone: ++49-69-6333-273/261/250 fax: ++49-69-6333-425 e-mail: [email protected] URL: www.iers.org ISSN: 1029-0060 (print version) ISBN: 978-3-86482-058-8 (print version) An online version of this document is available at: http://www.iers.org/AR2012 Druckerei: Bonifatius GmbH, Paderborn © Verlag des Bundesamts für Kartographie und Geodäsie, Frankfurt am Main, 2014 Table of Contents 1 Foreword.................................................................................................................. 5 2 The IERS 2.1 Structure........................................................................................................... 6 2.2 Directing Board................................................................................................. 9 2.3 Associate Members.......................................................................................... 10 3 Reports of IERS components 3.1 Directing Board.................................................................................................... 11 3.2 Central Bureau.................................................................................................... -
Wallace L. W. Sargent 1935–2012
Wallace L. W. Sargent 1935–2012 A Biographical Memoir by Charles C. Steidel ©2021 National Academy of Sciences. Any opinions expressed in this memoir are those of the author and do not necessarily reflect the views of the National Academy of Sciences. WALLACE L. W. SARGENT February 15, 1935-October 29, 2012 Elected to the NAS, 2005 Wallace L. W. Sargent was the Ira S. Bowen Professor of Astronomy at the California Institute of Technology, where he was a member of the astronomy faculty for 46 years, beginning in 1966. By any measure, Sargent— known to colleagues and friends as “Wal”—was one of the most influential and consistently productive observa- tional astronomers of the last 50 years. His impact on the field of astrophysics spanned a remarkably wide range of topics and was seminal in more than a few: the primor- dial helium abundance, young galaxies, galaxy dynamics, supermassive black holes, active galactic nuclei (AGN), Technology. Institute of Photography by California and, particularly, the intergalactic medium (IGM). Wal was 77 at the time of his death in 2012; he had maintained a full complement of teaching and research until just weeks By Charles C. Steidel before succumbing to an illness he had borne quietly for more than 15 years. Generations of students, postdocs, and colleagues benefited from Wal’s rare combination of scientific taste and intuition, intellectual interests extending far beyond science, irreverent sense of humor, and genuine concern about the well-being of younger scientists. Education and Early Influences Wal was born in 1935 in Elsham, Lincolnshire, United Kingdom—a small village roughly equidistant from Sheffield and Leeds in West Lincolnshire—into a working-class family.