Cosmic Noise: a History of Early Radio Astronomy Woodruff T
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32Nd Saas-Fee Course 2002
IAU Executive Committee P r e s i d e n t V i c e -P r e s i d e n t s Silvia Torres-Peimbert Instituto Astronomia Franco Pacini Catherine J. Cesarsky Dpto di Astronomia UNAM Director General, ESO Apt 70 264 Universitá degli Studi Karl Schwarzschildstr. 2 Largo E. Fermi 5 Mexico DF 04510, Mexico DE 85748 Garching, Tel: 52 5 622 3906 IT 50125 Firenze, Italy Germany Tel: 39 055 27521/2232 Fax: 52 5 616 0653 Tel: 49 893 200 6227 [email protected] Fax: 39 055 22 0039 Fax: 49 893 202 362 [email protected] [email protected] Robert E. Williams P r e s i d e n t -E l e c t STScI Norio Kaifu Homewood Campus Ronald D. Ekers Director General, NAO 3700 San Martin Dr CSIRO, ATNF Osawa, Mitaka US Baltimore MD 21218 Box 76 JP Tokyo 181- 8588, Japan USA AU Epping NSW 1710 Tel: 81 422 34 3650 Tel: 1 410 338 4963 Australia Fax: 81 422 34 3690 Fax: 1 410 338 2617 Tel: 61 2 9372 4300 [email protected] [email protected] Fax: 61 2 9372 4310 [email protected] Nikolay S. Kardashev A d v i s e r s Astro Space Center G e n e r a l S e c r e t a r y Lebedev Physical Institute Robert P. Kraft (Past President) Hans Rickman Academy of Sciences Profsojuznaya ul 84/32 Lick Observatory IAU RU 117810 Moscow University of California 98 bis Blvd Arago Russian Federation US Santa Cruz CA 95064 FR 75014 Paris, France Tel: 7 095 333 2378 USA Tel: 33 1 43 25 8358 Fax: 7 095 333 2378 Fax: 1 831 426 3115 Fax: 33 1 43 25 2616 or 7 095 310 7023 [email protected] [email protected] [email protected] Johannes Andersen H o m e I n s t i t u t e Kenneth A. -
The Iau Historic Radio Astronomy Working Group
THE IAU HISTORIC RADIO ASTRONOMY WORKING GROUP. 2: PROGRESS REPORT This Progress Report follows the inaugural report of the Working Group (WG), which appeared in the April 2004 ICHA Newsletter and was published in the June 2004 issue of the Journal of Astronomical History and Heritage (see Orchiston et al., 2004, below). Role of the WG This WG was formed at the 2003 General Assembly of the IAU as a joint initiative of Commissions 40 (Radio Astronomy) and 41 (History of Astronomy), in order to: • assemble a master list of surviving historically-significant radio telescopes and associated instrumentation found worldwide; • document the technical specifications and scientific achievements of these instruments; • maintain an on-going bibliography of publications on the history of radio astronomy; and • monitor other developments relating to the history of radio astronomy (including the deaths of pioneering radio astronomers). New Committee Members Since the last report was prepared we have added two further members to the Committee of the WG. As Chair of the WG, I am delighted to offer a warm welcome to Richard Wielebinski from the Max Planck Institute for Radioastronomy, representing Germany, and Jasper Wall (University of British Columbia), who represents Canada. Further Publications on the History of Radio Astronomy Balick, B., 2005. The discovery of Sagittarius A*. In Orchiston, 2005b, 183-190. Beekman, G., 1999. Een verjaardag zonder jarige. Zenit, 26(4), 154-157. Cohen, M., 2005. Dark matter and the Owens Valley Radio Observatory. In Orchiston, 2005b, 169-182. Davies, R.D., 2003. Fred Hoyle and Manchester. Astrophysics and Space Science, 285, 309- 319. -
What Asteroseismology Can Do for Exoplanets: Kepler-410A B Is a Small Neptune Around a Bright Star, in an Eccentric Orbit Consistent with Low Obliquity
What asteroseismology can do for exoplanets: Kepler-410A b is a Small Neptune around a bright star, in an eccentric orbit consistent with low obliquity V. Van Eylen1;2?, M. N. Lund1;4, V. Silva Aguirre1, T. Arentoft1, H. Kjeldsen1, S. Albrecht3, W. J. Chaplin5, H. Isaacson6, M. G. Pedersen1, J. Jessen-Hansen1, B. Tingley1, J. Christensen-Dalsgaard1, C. Aerts2, T. L. Campante5 and S. T. Bryson7 1 Stellar Astrophysics Centre, Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, DK-8000 Aarhus C, Denmark 2 Instituut voor Sterrenkunde, Katholieke Universiteit Leuven, Celestijnenlaan 200 B, B-3001 Heverlee, Belgium 3 Department of Physics, and Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA 4 Sydney Institute for Astronomy (SIfA), School of Physics, University of Sydney, NSW 2006, Australia 5 School of Physics and Astronomy, University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK 6 Department of Astronomy, University of California, Berkeley, CA 94820, USA 7 NASA Ames Research Center, Moffett Field, CA 94035 [email protected] ABSTRACT We confirm the Kepler planet candidate Kepler-410b (KOI-42b) as a Neptune sized exoplanet on a 17:8 day, eccentric orbit around the bright (Kp = 9:4) star Kepler-410A. This is the third brightest confirmed planet host star in the Kepler field and one of the brightest hosts of all currently known transiting exoplanets. Kepler-410 consists of a blend between the fast rotat- ing planet host star (Kepler-410A) and a fainter star (Kepler-410B), which has complicated the confirmation of the planetary candidate. -
Interview with Marshall Cohen
MARSHALL H. COHEN (1926- ) INTERVIEWED BY SHELLEY ERWIN November 1996, January-March 1997, and February 1999 1979 ARCHIVES CALIFORNIA INSTITUTE OF TECHNOLOGY Pasadena, California Subject area Astronomy Abstract Interview with Marshall H. Cohen, Caltech Professor of Astronomy, emeritus, by Shelley Erwin in six sessions and a supplement, 1996-1997, and 1999. He talks about his youth, family background, and education, and his early interest in electrical gadgets; wartime work for Westinghouse; higher education at Ohio State University: bachelor’s degree, electrical engineering, 1948; PhD in physics, 1952. Reminiscences of the Ohio State Antenna Lab and Vic Rumsey, 1952- 1954. Following appointment at Cornell in electrical engineering, Cohen describes his transition to the new field of radio astronomy. Recalls early participants in the field: J. Greenstein, F. Whipple, M. Ryle, B. Lovell, R. Hanbury Brown, E. G. Bowen, J. Bolton, P. Wild, W. Christiansen; British and Australian competition in interferometry; Caltech’s early entry in the field. Brief interlude recalls Richard Feynman both at Cornell and later at Caltech. Recalls establishment of National Radio Astronomy Observatory (NRAO), Green Bank, West Virginia; later sites in New Mexico. Cohen’s involvement with http://resolver.caltech.edu/CaltechOH:OH_Cohen_M ionospheric physics and building of Arecibo telescope in Puerto Rico. Recalls scientific work and political battles over Arecibo; colleagues E. Salpeter, T. Gold, B. Gordon. Cohen’s move to UC San Diego, 1966, and soon after, recruitment to Caltech, 1968. He recalls the developments of the 1960s: first US interferometer in Owens Valley; competition for buildings very large arrays; the Greenstein decadal committee (1970). Administrative information Access The interview is unrestricted. -
Instructional Lab for Undergraduates Utilizing the Hanbury Brown and Twiss Effect
Instructional Lab for Undergraduates Utilizing the Hanbury Brown and Twiss Effect Adam Kingsley A senior thesis submitted to the faculty of Brigham Young University in partial fulfillment of the requirements for the degree of Bachelor of Science Dallin Durfee, Advisor Department of Physics and Astronomy Brigham Young University December 2015 Copyright © 2015 Adam Kingsley All Rights Reserved ABSTRACT Instructional Lab for Undergraduates Utilizing the Hanbury Brown and Twiss Effect Adam Kingsley Department of Physics and Astronomy, BYU Bachelor of Science Using the classical Hanbury Brown and Twiss effect, students will measure correlation at two detectors far from an aperture in order to discover the diameter of the aperture. The light source will consist of a laser, spatially modulated so that the effect can still be observed and measurements can easily be made. The students will gain an increased understanding of angular size, spatial coherence, interference, and Rayleigh’s criterion. Keywords: Robert Hanbury Brown, Richard Q. Twiss, HBT Contents Table of Contents iii 1 Introduction1 1.1 The Hanbury Brown and Twiss Effect........................1 1.2 History of the Hanbury Brown and Twiss Effect...................1 1.3 Learning Outcomes..................................2 2 Explanation of the HBT Effect4 2.1 Description of the Hanbury Brown and Twiss Effect.................4 2.1.1 Analogy to Young’s Two-Slit Experiment..................5 2.2 Mathematical Description of the Correlation Function................5 2.3 Determining Angular Size from Spatial Coherence.................8 3 Numerical Exploration of a Possible Lab Experiment9 3.1 Numerical Calculations of the Second-Order Correlation Function.........9 3.2 Generating a Spatially Incoherent Light Source.................. -
From Radar to Radio Astronomy
John Bolton and the Nature of Discrete Radio Sources Thesis submitted by Peter Robertson BSc (Hons) Melbourne, MSc Melbourne 2015 for the degree of Doctor of Philosophy in the School of Agricultural, Computational and Environmental Sciences University of Southern Queensland ii Peter Robertson: ‘John Bolton and the Nature of Discrete Radio Sources’ Abstract John Bolton is regarded by many to be the pre-eminent Australian astronomer of his generation. In the late 1940s he and his colleagues discovered the first discrete sources of radio emission. Born in Sheffield in 1922 and educated at Cambridge University, in 1946 Bolton joined the Radiophysics Laboratory in Sydney, part of Australia’s Council for Scientific and Industrial Research. Radio astronomy was then in its infancy. Radio waves from space had been discovered by the American physicist Karl Jansky in 1932, followed by Grote Reber who mapped the emission strength across the sky, but very little was known about the origin or properties of the emission. This thesis will examine how the next major step forward was made by Bolton and colleagues Gordon Stanley and Bruce Slee. In June 1947, observing at the Dover Heights field station, they were able to show that strong radio emission from the Cygnus constellation came from a compact point-like source. By the end of 1947 the group had discovered a further five of these discrete radio sources, or ‘radio stars’ as they were known, revealing a new class of previously-unknown astronomical objects. By early 1949 the Dover Heights group had measured celestial positions for the sources accurately enough to identify three of them with known optical objects. -
What Asteroseismology Can Do for Exoplanets: KOI-42Ab Is a Small Neptune in an Eccentric Orbit Consistent with Low Obliquity
What asteroseismology can do for exoplanets: KOI-42Ab is a Small Neptune in an eccentric orbit consistent with low obliquity V. Van Eylen1;2?, M. N. Lund1;4, V. Silva Aguirre1, T. Arentoft1, H. Kjeldsen1, S. Albrecht3, W. J. Chaplin5, H. Isaacson6, M. G. Pedersen1, J. Jessen-Hansen1, B. Tingley1, J. Christensen-Dalsgaard1, C. Aerts2 and T. Campante5 1 Stellar Astrophysics Centre, Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, DK-8000 Aarhus C, Denmark 2 Instituut voor Sterrenkunde, Katholieke Universiteit Leuven, Celestijnenlaan 200 B, B-3001 Heverlee, Belgium 3 Department of Physics, and Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA 4Sydney Institute for Astronomy (SIfA), School of Physics, University of Sydney, NSW 2006, Australia 5School of Physics and Astronomy, University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK 6Department of Astronomy, University of California, Berkeley, CA 94820, USA [email protected] ABSTRACT We confirm the Kepler planet candidate KOI-42b as a Neptune sized exoplanet on a 17:8 day, eccentric, orbit around the bright (Kp = 9:4) star KOI-42A. KOI-42 consists of a blend between the fast rotating planet host star (KOI-42A) and a fainter star (KOI-42B), which has complicated the confirmation of the planetary candidate. Employing asteroseismology, using constraints from the transit light curve, adaptive optics and speckle images, and Spitzer transit observations, we demonstrate that the candidate can only be an exoplanet orbiting KOI-42A. Via asteroseismology we determine the following stellar and planetary parameters with high precision; M? = 1:214 ± 0:033 M ,R? = 1:352 ± 0:010 R , Age = 2:76 ± 0:54 Gyr, planetary radius (2:838 ± 0:054 R⊕), and +0:10 orbital eccentricity (0:17−0:05). -
Transit Timing Variations, Radial Velocities and Long-Term Dynamical Stability of the System Kepler-410?
MNRAS 484, 4352{4359 (2019) Preprint 12th February 2019 Compiled using MNRAS LATEX style file v3.0 Transit timing variations, radial velocities and long-term dynamical stability of the system Kepler-410? Pavol Gajdoˇs1†, Martin Vaˇnko2, Theodor Pribulla2, Daniel Dupkala3,4, J´an Subjakˇ 3,4, Marek Skarka3,5, Petr Kab´ath3, L'ubom´ır Hamb´alek2, Stefanˇ Parimucha1 1Institute of Physics, Faculty of Science, Pavol Jozef Saf´arikˇ University, Koˇsice, Slovakia 2Astronomical Institute, Slovak Academy of Sciences, 059 60 Tatransk´aLomnica, Slovakia 3Astronomical Institute, Czech Academy of Sciences, Friˇcova 298, 25165, Ondˇrejov, Czech Republic 4Astronomical Institute of Charles University, V Holeˇsoviˇck´ach 2, 180 00, Praha, Czech Republic 5Department of Theoretical Physics and Astrophysics, Masaryk Univerzity, Kotl´aˇrsk´a2, 61137 Brno, Czech Republic Accepted 2019 January 22. Received 2019 January 21; in original form 2018 December 14. ABSTRACT Transit timing variations of Kepler-410Ab were already reported in a few papers. Their semi-amplitude is about 14.5 minutes. In our previous paper, we found that the transit timing variations could be caused by the presence of a stellar companion in this system. Our main motivation for this paper was to investigate variation in a radial-velocity curve generated by this additional star in the system. We performed spectroscopic observation of Kepler-410 using three telescopes in Slovakia and Czech Republic. Using the cross-correlation function, we measured the radial velocities of the star Kepler-410A. We did not observe any periodic variation in a radial-velocity curve. Therefore, we rejected our previous hypothesis about additional stellar companion in the Kepler-410 system. -
Progress Report
Journal of Astronomical History and Heritage, 7: 53-56 (2004) The IAU Historic Radio Astronomy Working Group. 1: Progress Report Wayne Orchiston Anglo-Australian Observatory, and Australia Telescope National Facility, PO Box 296, Epping, NSW 2121, Australia E-mail: [email protected] Rod Davies Jodrell Bank, University of Manchester, Macclesfield, SK11 9DL, U.K. E-mail: [email protected] Jean-Francois Denisse 48 rue Mr Le Prince, 75006 Paris, France E-mail messages to: [email protected] Ken Kellermann National Radio Astronomy Observatory, 520 Edgemont Rd., Charlotteville, VA 22903-2475, U.S.A. E-mail: [email protected] Masaki Morimoto Nishi Harima Astronomical Observatory, 407 2 Nishi Kawachi, Sayoh Cho, Hyohgo 679 5313, Japan E-mail: [email protected] Slava Slysh Astronomy Space Center, Lebedev Physical Institute, PrBoxsojuznaya Ul 84/32, 117810 Moscow, Russia E-mail: [email protected] Govind Swarup NCRA TIFR, Pune University Campus Pb3, Ganeshkind, Pune 411 007, India E-mail: [email protected] Hugo van Woerden Kapteyn Sterrekundig Instituut, University of Groningen, Box 800, 9700 AV Groningen, The Netherlands E-mail: [email protected] This new Working Group was established at the Australia’s pioneering efforts in international radio July 2003 IAU General Assembly in Sydney, with a astronomy, it was only natural that such sessions view to: should form part of the program at the Sydney GA, (1) assembling a master list of surviving and it was pleasing to see that they drew capacity historically-significant radio telescopes and audiences. Science Meeting 2, on “The Early associated instrumentation found world- Development of Australian Radio Astronomy”, ran wide; all day on July 21, and attracted the following oral (2) documenting the technical specifications and and poster papers: scientific achievements of such instruments; (3) maintaining an on-going bibliography of Sullivan, W. -
First Image with the ATCA EW 352/367 Configurations
ATNF News Issue No. 47, June 2002 ISSN 1323-6326 FEATURES First image with the ATCA IN THIS EW 352/367 configurations ISSUE Naomi McClure-Griffiths and the Southern Galactic Plane Survey team First image for EW 352/367 configs Page 1 Three Bolton Fellows appointed to ATNF Page 3 URSI Young Scientist Awards Page 5 The SEARFE Project Page 6 Workshop at Kerastari, Greece Page 8 VLBI astrometry Page 10 Figure 1: HI image at v=36.3 km/s of Galactic chimney GSH 277+00+36. This image was created from a 1065 pointing mosaic, mainly observed with the EW 352/367 arrays. The greyscale is linear from 5 to 90 K as shown in the wedge on the right. The flowering of Fleurs The pairing of the newly commissioned EW In the 2000 September and 2001 January 352 and EW 367 ATCA configurations offer terms we used the new arrays for 21 cm Page 12 almost complete coverage of all baselines continuum and HI spectral line observations from 31 to 367 m. Users of the ATCA’s old of the Galactic chimney, GSH 277+00+36. Square Kilometre 375 m configuration have long been plagued Figure 1 is the HI image of the shell at Array program by the even multiples of the fundamental v=36.3 km/s created from these Page 16 15.3 m baseline increment, which resulted observations. GSH 277+00+36 is a very in more than a few images with a nasty large chimney approximately 6.5 kpc from grating lobe near strong sources. -
Universel Registration Document
For translation purposes only Universel Registration Document Fiscal year 2020 The Registration Document was approved on 18 June 2021 by the Autorité des marchés financiers (AMF), in its capacity as competent authority under Regulation (EU) No 2017/1129. The Autorité des Marchés Financiers (AMF) approves this universal registration document after having verified that the information contained in it is complete, consistent and understandable. The universal registration document has the following approval number: R.21-035. Such approval should not be regarded as a favourable opinion on the issuer that is the subject of the universal registration document. The universal registration document may be used for the purpose of a public offering of financial securities or the admission of financial securities to trading on a regulated market if it is supplemented by a prospectus and, where applicable, a summary and its amendment (s). In such cases, the securities note, the summary and all amendments to the universal registration document since its approval shall be approved separately in accordance with the second subparagraph of Article 10 (3) of Regulation (EU) No 2017/1129. The Universal Registration Document is valid until 18 June 2022 and, during this period and at the latest at the same time as the Transaction Note and under the conditions of Articles 10 and 23 of Regulation (EU) No 2017/1129, will have to be supplemented by a supplement to the Universal Registration Document in the event of significant new facts or substantial errors or inaccuracies. Copies of this universal registration document are available free of charge: • At the Company's registered office or on the Company's website; • And on the AMF website (www.amf france.org). -
Some Milestones in History of Science About 10,000 Bce, Wolves Were Probably Domesticated
Some Milestones in History of Science About 10,000 bce, wolves were probably domesticated. By 9000 bce, sheep were probably domesticated in the Middle East. About 7000 bce, there was probably an hallucinagenic mushroom, or 'soma,' cult in the Tassili-n- Ajjer Plateau in the Sahara (McKenna 1992:98-137). By 7000 bce, wheat was domesticated in Mesopotamia. The intoxicating effect of leaven on cereal dough and of warm places on sweet fruits and honey was noticed before men could write. By 6500 bce, goats were domesticated. "These herd animals only gradually revealed their full utility-- sheep developing their woolly fleece over time during the Neolithic, and goats and cows awaiting the spread of lactose tolerance among adult humans and the invention of more digestible dairy products like yogurt and cheese" (O'Connell 2002:19). Between 6250 and 5400 bce at Çatal Hüyük, Turkey, maces, weapons used exclusively against human beings, were being assembled. Also, found were baked clay sling balls, likely a shepherd's weapon of choice (O'Connell 2002:25). About 5500 bce, there was a "sudden proliferation of walled communities" (O'Connell 2002:27). About 4800 bce, there is evidence of astronomical calendar stones on the Nabta plateau, near the Sudanese border in Egypt. A parade of six megaliths mark the position where Sirius, the bright 'Morning Star,' would have risen at the spring solstice. Nearby are other aligned megaliths and a stone circle, perhaps from somewhat later. About 4000 bce, horses were being ridden on the Eurasian steppe by the people of the Sredni Stog culture (Anthony et al.