Jodrell Bank Observatoryvisitreport

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U3A Jodrell Bank Observatory Visit, March 2015 I’m sure you will all instantly recognise the equation z = a(x 2 + y 2) as that of an elliptical parabaloid. This of course, we were informed by Jodrell Bank, describes the shape of the dish of a radio-telescope, so that distant radio waves will be focussed on a receiver in the centre. And who am I to argue with them. 24 intrepid trekkers braved the rain on the 13 th March and climbed the many steps of Hednesford Travel’s coach, to arrive at the Observatory in rural Cheshire. Now part of Manchester University, it was located there on purpose, to be in a better “radio quiet” area, if that is possible these days. Switching off mobile phones was our first request on entering. The obvious landmark that greeted us was the enormous Lovell radio-telescope, 76 metres in diameter, which started receiving signals from outer space in 1957. Although we couldn’t get close enough to touch it, nor get in the control room, we did manage to get a few group photos in front of it before leaving. At least we did see it pan across the sky and rotate on its axis with quite loud grumbling noises. Well, it is an old timer now after all. Lovell managed to get the huge telescope up and running after his wartime development into radar, thinking that the receiving equipment developed could be put to other uses. During a talk from a physicist who also doubles as an educator, we were told about the parts of the electromagnetic spectrum that the Lovell telescope receives, which was from microwave frequencies upwards towards the infra-red bands. Different agencies around the world request data received from Pulsars, Quasars and cosmic microwave background signals, which the telescope can track. To increase the sensitivity of the dish, other radio-telescopes around the world are harnessed to track together with Jodrell. To ensure correct synchronisation of all the dishes, it necessitated the making of an atomic clock for accuracy, which was based at Jodrell, so that time delays between signals from dishes can be compensated. A square kilometre array of dishes is due to be built in South Africa to increase signal power. These will be in the shape of spirals from a central spot, and is being planned by Jodrell Bank engineers. Several spacecraft have also included receivers built at Jodrell, such as Planck. The receiver in the Lovell telescope has to be made so sensitive, that it must be cooled to -260 degrees Centigrade, to reduce electronic noise to virtually zero (typically hiss). This enables very feint radio signals to be heard from outer space, but makes the receivers extremely complex with cooling cryogenics from liquid gases such as nitrogen. Around the area of the lecture theatre were several video and static displays, showing all the areas that Jodrell were involved in. With 35 acres of landscaped gardens, and a café with a wonderful menu, this visit was a very interesting day out, and enjoyed by all. Barry James Cannock Chase U3A .

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50 Years of the Lovell Telescope Transcript
50 years of the Lovell telescope Transcript Date: Wednesday, 5 December 2007 - 12:00AM 50 YEARS OF THE LOVELL TELESCOPE Professor Ian Morison The Early days at Jodrell Bank In late 1945 Dr Bernard Lovell (as he then was) returned to Manchester University after working on the development of radar during the war years. His aim was to continue his researches into cosmic rays - highly energetic particles that enter the Earth's atmosphere from outer space. He had the idea that sporadic echoes sometimes received by military radars might be the result of cosmic rays entering the atmosphere and thus radar observations might provide a new way to continue his researches. Radar observations were not practical in the centre of Manchester so he took his ex-army radar system out to the University's Botanical Grounds at Jodrell Bank, some 20 miles to the south. By the middle of December 1945, the system was operating and his team was soon able to prove that the echoes were coming not from cosmic rays but from ionized meteor trails left behind when small particles, released from comets, are burnt up in the upper atmosphere of the Earth. Radar Antenna in the Botany Grounds. The Jodrell Bank Experimental Station. The observations continued and, to house the expanding staff and equipment, the Jodrell Bank Experimental Station was built in the field next to the Botanic Grounds. Lovell realised that a much more sensitive radio telescope would be required to detect cosmic rays and so, in 1947, the researchers built a large parabolic reflector, 66-m across, pointing upwards to observe the sky passing overhead.
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The Lovell Telescope … Through Its Surfaces Simon Garrington, JBO/University of Manchester
The Lovell Telescope … through its surfaces Simon Garrington, JBO/University of Manchester • Original design & redesign: 1950-1957 • Radical modification & new surface: 1971 • Replacement of surface: 2001 • Replacement of original Picture A. Holloway surface: 2018 • Other consequences: foundations O1 Original MkI proposal and changes • Concept & proposals: 1950-1 • Lovell-Husband Sep 1949 • Radio Astronomy Cttee 1950 • rail track; towers, cradle, 4-inch mesh • 2-inch mesh/5-in profile by 20 Mar 1951 submission • Design changes • 21cm line discovered (Ewen 25 Mar 1951) • Inner 100’ mesh 1x2-in ‘at no cost’ ? Sep 1952 • Interest from Air Ministry: 10cm radar • March 1954: 3/4-in mesh -> stronger cradle … but Air Ministry step back O2 Original MkI proposal and changes • Concept & proposals: 1950-1 • Lovell-Husband Sep 1949 • Radio Astronomy Cttee 1950 • rail track; towers, cradle, 4-inch mesh • 2-inch mesh/5-in profile by 20 Mar 1951 submission • Design changes • 21cm line discovered (Ewen 25 Mar 1951) • Inner 100’ mesh 1x2-in ‘at no cost’ ? Sep 1952 • Interest from Air Ministry: 10cm radar • March 1954: 3/4-in mesh -> stronger cradle … but Air Ministry step back O3 Original MkI proposal and changes • Concept & proposals: 1950-1 • Lovell-Husband Sep 1949 • Radio Astronomy Cttee 1950 • rail track; towers, cradle, 4-inch mesh • 2-inch mesh/5-in profile by 20 Mar 1951 submission • Design changes • 21cm line discovered (Ewen 25 Mar 1951) • Inner 100’ mesh 1x2-in ‘at no cost’ ? Sep 1952 • Interest from Air Ministry: 10cm radar • March 1954: 3/4-in
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Adventures in Radio Astronomy Instrumentation and Signal Processing
Adventures in Radio Astronomy Instrumentation and Signal Processing by Peter Leonard McMahon Submitted to the Department of Electrical Engineering in partial fulﬁllment of the requirements for the degree of Master of Science in Electrical Engineering at the University of Cape Town July 2008 Supervisor: Professor Michael Inggs Co-supervisors: Dr Dan Werthimer, CASPER1, University of California, Berkeley Dr Alan Langman, Karoo Array Telescope arXiv:1109.0416v1 [astro-ph.IM] 2 Sep 2011 1Center for Astronomy Signal Processing and Electronics Research Abstract This thesis describes the design and implementation of several instruments for digi- tizing and processing analogue astronomical signals collected using radio telescopes. Modern radio telescopes have signiﬁcant digital signal processing demands that are typically best met using custom processing engines implemented in Field Pro- grammable Gate Arrays. These demands essentially stem from the ever-larger ana- logue bandwidths that astronomers wish to observe, resulting in large data volumes that need to be processed in real time. We focused on the development of spectrometers for enabling improved pulsar2 sci- ence on the Allen Telescope Array, the Hartebeesthoek Radio Observatory telescope, the Nan¸cay Radio Telescope, and the Parkes Radio Telescope. We also present work that we conducted on the development of real-time pulsar timing instrumentation. All the work described in this thesis was carried out using generic astronomy pro- cessing tools and hardware developed by the Center for Astronomy Signal Processing and Electronics Research (CASPER) at the University of California, Berkeley. We successfully deployed to several telescopes instruments that were built solely with CASPER technology, which has helped to validate the approach to developing radio astronomy instruments that CASPER advocates.
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High Resolution Radio Astronomy Using Very Long Baseline Interferometry
IOP PUBLISHING REPORTS ON PROGRESS IN PHYSICS Rep. Prog. Phys. 71 (2008) 066901 (32pp) doi:10.1088/0034-4885/71/6/066901 High resolution radio astronomy using very long baseline interferometry Enno Middelberg1 and Uwe Bach2 1 Astronomisches Institut, Universitat¨ Bochum, 44801 Bochum, Germany 2 Max-Planck-Institut fur¨ Radioastronomie, Auf dem Hugel¨ 69, 53121 Bonn, Germany E-mail: [email protected] and [email protected] Received 3 December 2007, in final form 11 March 2008 Published 2 May 2008 Online at stacks.iop.org/RoPP/71/066901 Abstract Very long baseline interferometry, or VLBI, is the observing technique yielding the highest-resolution images today. Whilst a traditionally large fraction of VLBI observations is concentrating on active galactic nuclei, the number of observations concerned with other astronomical objects such as stars and masers, and with astrometric applications, is significant. In the last decade, much progress has been made in all of these fields. We give a brief introduction to the technique of radio interferometry, focusing on the particularities of VLBI observations, and review recent results which would not have been possible without VLBI observations. This article was invited by Professor J Silk. Contents 1. Introduction 1 2.9. The future of VLBI: eVLBI, VLBI in space and 2. The theory of interferometry and aperture the SKA 10 synthesis 2 2.10. VLBI arrays around the world and their 2.1. Fundamentals 2 capabilities 10 2.2. Sources of error in VLBI observations 7 3. Astrophysical applications 11 2.3. The problem of phase calibration: 3.1. Active galactic nuclei and their jets 12 self-calibration 7 2.4.
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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.
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Pos(10Th EVN Symposium)097
La Luna: Lovell Attempts LUnar Neutrino Acquisition PoS(10th EVN Symposium)097 Ralph Spencer 1, Alan Macfarlane, Owen Mills and Lucio Piccirillo School of Physics and Astronomy, The University of Manchester Oxford Rd., Manchester M13 9PL, UK E-mail: [email protected] Recent measurements by the Pierre Auger array have found evidence for the Greisen-Zatsepin- Kuzmin (GZK) cut off in the high energy spectrum of cosmic rays. Interactions of cosmic rays with energies of greater than ~0.05 ZeV with the cosmic microwave background are expected to produce high energy neutrinos. It has been suggested that neutrino interactions in the Moon can give rise to showers of particles, which through the Askar’yan charge excess mechanism can produce Cherenkov emission in the radio, detectable from the Earth. Here we describe a preliminary experiment at 21 cm with the Lovell telescope, which produces limits comparable with those from other radio telescopes. Use of VLBI telescopes in coincidence would eliminate local impulsive RFI and also possibly be able to measure the width of the Cherenkov cone 10th European VLBI Network Symposium and EVN Users Meeting: VLBI and the new generation of radio arrays Manchester, UK September 20-24 1 Copyright owned by the author(s) under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike Licence. http://pos.sissa.it Short title Speaker Name 1.Introduction The study of ultra-high-energy (UHE) neutrinos has the potential to be an important tool in the study of many energetic astronomical phenomena. Neutrinos with energies in excess of 10 20 eV are predicted to be produced by processes such as gamma-ray bursts, active galactic nuclei, topological defects and decays of massive relic particles [1].
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2020 the Pathfinder View of the Sky LEGEND Canadian Hydrogen Intensity Mapping European VLBI Experiment (CHIME) - Network (EVN) - Canada Europe
Calendar 2020 The Pathfinder View of the Sky LEGEND Canadian Hydrogen Intensity Mapping European VLBI Experiment (CHIME) - Network (EVN) - Canada Europe enhanced Multi Element Remotely NenuFAR - France Linked Interferometer Network (e-MERLIN) - United Kingdom Low Frequency Array (LOFAR) - the MeerKAT Radio Netherlands Telescope - South Africa Five-hundred-meter Aperture Spherical Australian SKA Telescope (FAST) - Pathﬁnder (ASKAP) - China Australia (CHIME) Giant Metrewave Murchison Wideﬁeld Radio Telescope Array (MWA) - (GMRT) - India Australia VLBI Exploration of Effelsberg 100m Members of the SKA Organisation African Partner Countries Radio Astrometry Radio Telescope - Host Countries: Australia, South Africa, United Kingdom (VERA) - Japan Germany In the lead up to the SKA, many new groundbreaking radio elusive Fast Radio Bursts. They’re also allowing engineers The 2020 SKA calendar, called The Pathfinder View of the astronomy facilities have sprung up around the world in to develop new technical solutions like aperture arrays or Sky and featuring a small selection of the results already the past 10 years. These facilities are part of a global Phased Array Feeds. In so doing, they are paving the way coming out of 12 of these telescopes, is our tribute to effort to design and build ever-more sensitive instruments for the world’s largest radio telescope, the SKA. the pathfinder family as a whole, the people who have built to detect some of the faintest signals in the universe them and the people who are using them. The knowledge These facilities are now open to the community or going and grow new scientific and technical communities while and experience they’ve accumulated will guide us through through commissioning, and already they are providing benefiting society through cutting-edge R&D.
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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!
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Bernard Lovell (1913-2012) Physicist and Radar Pioneer Who Created the Famous Jodrell Bank Radio Telescope
COMMENT OBITUARY Bernard Lovell (1913-2012) Physicist and radar pioneer who created the famous Jodrell Bank radio telescope. ith vision, inspiration and deter- a small team built a parabolic reflector in the Western world. Suddenly everyone mination, Bernard Lovell created 66 metres in diameter, made of wires stretched realized the telescope’s importance. Lord the Jodrell Bank Observatory in between scaffold poles. Robert Hanbury Nuffield paid off the debt, half personally WCheshire, UK, and the great radio telescope Brown used this dish to discover radio waves and half from the Nuffield Foundation, and there that bears his name. Through his lead- from the Andromeda galaxy. It was the start serious astronomy could begin. ership, generations of astronomers developed of astronomy at Jodrell Bank. That dish was The telescope fulfilled Lovell’s vision of the tools of radio astronomy that have revo- fixed and could only stare upwards. Lovell’s opening a new window on the Universe. It lutionized astrophysics and cosmology. had illustrious roles in early space explo- Lovell was born in Oldland Common ration, in the discovery of quasars and the near Bristol, UK, and educated at the local first gravitational lens, and in the discov- Kingswood Grammar School. He was ery and study of pulsars, or neutron stars, PHOTOSHOT PHOTOSHOT attracted to science through a lecture by which have provided the most precise physicist Arthur Tyndall. He joined Tyn- tests of Einstein’s general theory of rela- dall as a research student at the University tivity. After 55 years and two major refur- of Bristol, where his meticulous work on bishments, the telescope is still working at the resistance of thin metallic films earned the frontiers of knowledge.
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Executive Summary Executive Summary 13 372000 376000 380000 384000 388000 ´ 0 0 0 0 0 0 2 2 7 7 3 3
0 379400 379600 379800 380000 0 0 0 4 4 1 1 7 535 7 3 A 3 Car Park Granada Arboretum ´ Executive Discovery Centre 0 0 0 0 2 2 1 1 7 7 Summary 3 3 Lovell Telescope State Party A4 or A3 size map(s) of world. Constructed between 1952 the nominated property, and 1957, its first act was to track the United Kingdom carrier rocket for Sputnik 1, the first 0 0 0 0 0 0 showing boundaries and 1 1 satellite ever launched into orbit and 7 7 State, Province or Region buffer zone (if present) humanity’s first step into space. The 3 3 Telescope was the largest of its kind England (Cheshire East administrative See maps enclosed in dossier. in the world for 15 years and inspired Square Kilometre authority) Array Headquarters the construction of many other Criteria under which instruments worldwide. Name of Property property is nominated The property encompasses a number Jodrell Bank Observatory (itemize criteria) of other radio telescopes, including Geographical Coordinates (i), (ii), (iv), (vi) the Mark II Telescope, and functional Bridge Farm 0 0 buildings on a 17.38-hectare site. Many 0 0 8 8 to the nearest second 0 0 Draft Statement of of these are original structures and 7 7 3 3 instruments, while remnants of earlier N 53° 14’ 05” W 2° 18’ 18” Outstanding Universal Value structures also persist, some of them Textual description of the a. Brief Synthesis below ground. boundary of the nominated Jodrell Bank Observatory is the earliest The character of the Observatory has property radio astronomy observatory in the been determined by the evolution of world that is still in existence.
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Real-Time Adaptive RFI Masking for Radio Transient and Pulsar Searches
MNRAS 000,1–10 (2021) Preprint 31 August 2021 Compiled using MNRAS LATEX style file v3.0 IQRM: real-time adaptive RFI masking for radio transient and pulsar searches V. Morello,1¢ K. M. Rajwade,1 and B.W. Stappers1 1Jodrell Bank Centre for Astrophysics, Department of Physics and Astronomy, The University of Manchester, Manchester M13 9PL Accepted XXX. Received YYY; in original form ZZZ ABSTRACT In a search for short timescale astrophysical transients in time-domain data, radio-frequency interference (RFI) causes both large quantities of false positive candidates and a significant reduction in sensitivity if not correctly mitigated. Here we propose an algorithm that infers a time-variable frequency channel mask directly from short-duration (∼1 s) data blocks: the method consists of computing a spectral statistic that correlates well with the presence of RFI, and then finding high outliers among the resulting values. For the latter task, we propose an outlier detection algorithm called Inter-Quartile Range Mitigation (IQRM), that is both non-parametric and robust to the presence of a trend in sequential data. The method requires no training and can in principle adapt to any telescope and RFI environment; its efficiency is shown on data from both the MeerKAT and Lovell 76-m radio telescopes. IQRM is fast enough to be used in a streaming search and has been integrated into the MeerTRAP real-time transient search pipeline. Open-source python and C++ implementations are provided. Key words: methods: data analysis – fast radio bursts – pulsars: general 1 INTRODUCTION however they are required to handle large volumes of data in real time and thus tend to be limited to simple thresholding and replacement Radio-frequency interference broadly refers to all signals that neg- schemes.
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Radio Telescopes and Interferometers in the World
Radio Telescopes and Interferometers in the World 澤田-佐藤聡子 사와다-사토우 사토코 Satoko SAWADA-SATOH (山口大学, 야마구치대학, Yamaguchi University) Second Asian Radio Astronomy School Aug 18-22, 2008 at ASIAA, Taipei World Radio Telescope Tour ! (...but not in East Asia) 1. Big Antenna 2. Interferometry 3. VLBI Big Antenna ~ Towards higher sensitivity Arecibo (National Astronomy and Ionosphere Center ) • The largest single aperture ~ 73000 m2 • Diameter : 305 m • Location : Puerto Rico • Band : 50 MHz to 10 GHz • Maximum Angular Resolution : 30'' RATAN-600 (Special Astrophysics Observatory) • The world's largest radio telescope • 576 meter diameter of circular antenna with tilt-able curved and flat reflectors • Location : Zelenchukskaya, Russia • Aperture : ~15000 m2 • Band : 600 MHz to 30 GHz • Maximum Angular Resolution : 2'' Effelsberg Telescope (Max Planck Institut) • The 100-m diameter alt-azimuth mounted antenna • The largest fully steerable radio telescope for 30 years • Location : Effelsberg, near Bonn, Germany • Aperture : 7854 m2 • Band : 800 MHz to 96 GHz • Maximum Angular Resolution : 60'' Green Bank Telescope (NRAO) • Parabolic off axis reflector • The world's largest fully steerable radio telescope – 100 m x 110 m diameter • Location : Green Bank, West Virginia, USA • Band : 300 MHz to 50 GHz • Maximum Angular Resolution : 120'' Lovell Telescope (Jodrell Bank Observatory) • A 76-m alt-azimuth mounted parabolic dish antenna • Location : Cheshire, in the north-west of England • Band : Up to ~ 5 GHz • Maximum Angular Resolution : 160'' Tidbinbilla
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