Expanding the Frontiers of Space
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IVS NICT-TDC News No.39
ISSN 1882-3432 CONTENTS Proceedings of the 18th NICT TDC Symposium (Kashima, October 1, 2020) KNIFE, Kashima Nobeyama InterFErometer . 3 Makoto Miyoshi Space-Time Measurements Research Inspired by Kashima VLBI Group . 8 Mizuhiko Hosokawa ALMA High Frequency Long Baseline Phase Correction Using Band-to-band ..... 11 (B2B) Phase Referencing Yoshiharu Asaki and Luke T. Maud Development of a 6.5-22.5 GHz Very Wide Band Feed Antenna Using a New ..... 15 Quadruple-Ridged Antenna for the Traditional Radio Telescopes Yutaka Hasegawa*, Yasumasa Yamasaki, Hideo Ogawa, Taiki Kawakami, Yoshi- nori Yonekura, Kimihiro Kimura, Takuya Akahori, Masayuki Ishino, Yuki Kawa- hara Development of Wideband Antenna . 18 Hideki Ujihara Performance Survey of Superconductor Filter Introduced in Wideband Re- ..... 20 ceiver for VGOS of the Ishioka VLBI Station Tomokazu Nakakuki, Haruka Ueshiba, Saho Matsumoto, Yu Takagi, Kyonosuke Hayashi, Toru Yutsudo, Katsuhiro Mori, Tomokazu Kobayashi, and Mamoru Sekido New Calibration Method for a Radiometer Without Using Liquid Nitrogen ..... 23 Cooled Absorber Noriyuki Kawaguchi, Yuichi Chikahiro, Kenichi Harada, and Kensuke Ozeki Comparison of Atmospheric Delay Models (NMF, VMF1, and VMF3) in ..... 27 VLBI analysis Mamoru Sekido and Monia Negusini HINOTORI Status Report . 31 Hiroshi Imai On-the-Fly Interferometer Experiment with the Yamaguchi Interferometer . 34 Kenta Fujisawa, Kotaro Niinuma, Masanori Akimoto, and Hideyuki Kobayashi Superconducting Wide-band BRF for Geodetic VLBI Observation with ..... 36 VGOS Radio Telescope -
Orbital Phase Resolved Spectroscopy of 4U1538-52 with MAXI
Astronomy & Astrophysics manuscript no. jjrr-mif-maxi_rev5 c ESO 2018 September 12, 2018 Orbital phase resolved spectroscopy of 4U1538−52 with MAXI J. J. Rodes-Roca1, 2, 3,,⋆ T. Mihara3, S. Nakahira4, J. M. Torrejón1, 2, Á. Giménez-García1, 2, 5, and G. Bernabéu1, 2 1 Dept. of Physics, Systems Engineering and Sign Theory, University of Alicante, 03080 Ali- cante, Spain e-mail: [email protected] 2 University Institute of Physics Applied to Sciences and Technologies, University of Alicante, 03080 Alicante, Spain 3 MAXI team, Institute of Physical and Chemical Research (RIKEN), 2-1 Hirosawa, Wako, Saitama 351-0198, Japan e-mail: [email protected] 4 ISS Science Project Office, Institute of Space and Astronautical Science (ISAS), Japan Aerospace Exploration Agency (JAXA), 2-1-1 Sengen, Tsukuba, Ibaraki 305-8505, Japan 5 School of Physics, Faculty of Science, Monash University, Clayton, Victoria 3800, Australia XX-XX-XX; XX-XX-XX ABSTRACT Context. 4U 1538−52, an absorbed high mass X-ray binary with an orbital period of ∼3.73 days, shows moderate orbital intensity modulations with a low level of counts during the eclipse. Sev- eral models have been proposed to explain the accretion at different orbital phases by a spherically arXiv:1507.04274v2 [astro-ph.HE] 18 Jul 2015 symmetric stellar wind from the companion. Aims. The aim of this work is to study both the light curve and orbital phase spectroscopy of this source in the long term. Particularly, the folded light curve and the changes of the spectral parameters with orbital phase to analyse the stellar wind of QV Nor, the mass donor of this binary system. -
Pushing the Limits of the Coronagraphic Occulters on Hubble Space Telescope/Space Telescope Imaging Spectrograph
Pushing the limits of the coronagraphic occulters on Hubble Space Telescope/Space Telescope Imaging Spectrograph John H. Debes Bin Ren Glenn Schneider John H. Debes, Bin Ren, Glenn Schneider, “Pushing the limits of the coronagraphic occulters on Hubble Space Telescope/Space Telescope Imaging Spectrograph,” J. Astron. Telesc. Instrum. Syst. 5(3), 035003 (2019), doi: 10.1117/1.JATIS.5.3.035003. Downloaded From: https://www.spiedigitallibrary.org/journals/Journal-of-Astronomical-Telescopes,-Instruments,-and-Systems on 02 Jul 2019 Terms of Use: https://www.spiedigitallibrary.org/terms-of-use Journal of Astronomical Telescopes, Instruments, and Systems 5(3), 035003 (Jul–Sep 2019) Pushing the limits of the coronagraphic occulters on Hubble Space Telescope/Space Telescope Imaging Spectrograph John H. Debes,a,* Bin Ren,b,c and Glenn Schneiderd aSpace Telescope Science Institute, AURA for ESA, Baltimore, Maryland, United States bJohns Hopkins University, Department of Physics and Astronomy, Baltimore, Maryland, United States cJohns Hopkins University, Department of Applied Mathematics and Statistics, Baltimore, Maryland, United States dUniversity of Arizona, Steward Observatory and the Department of Astronomy, Tucson Arizona, United States Abstract. The Hubble Space Telescope (HST)/Space Telescope Imaging Spectrograph (STIS) contains the only currently operating coronagraph in space that is not trained on the Sun. In an era of extreme-adaptive- optics-fed coronagraphs, and with the possibility of future space-based coronagraphs, we re-evaluate the con- trast performance of the STIS CCD camera. The 50CORON aperture consists of a series of occulting wedges and bars, including the recently commissioned BAR5 occulter. We discuss the latest procedures in obtaining high-contrast imaging of circumstellar disks and faint point sources with STIS. -
Large-Angle Observatory with Energy Resolution for Synoptic X-Ray Studies (LOBSTER-SXS) ∗ Paul Gorenstein , Harvard-Smithsonian Center for Astrophysics, 60 Garden St
Large-angle OBServaTory with Energy Resolution for Synoptic X-ray Studies (LOBSTER-SXS) ∗ Paul Gorenstein , Harvard-Smithsonian Center for Astrophysics, 60 Garden St. MS-4, Cambridge, MA USA 02138 ABSTRACT The soft X-ray band hosts a larger, more diverse range of variable sources than any other region of the electromagnetic spectrum. They are stars, compact binaries, SMBH’s, the X-ray components of Gamma-Ray Bursts, their X-ray afterglows, and soft X-ray flares from supernova. We describe a concept for a very wide field (~ 4 ster) modular hybrid X-ray telescope system that can measure positions of bursts and fast transients with as good as arc second accuracy, the precision required to identify fainter and increasingly more distant events. The dimensions and materials of all telescope modules are identical. All but two are part of a cylindrical lobster-eye telescope with flat double sided mirrors that focus in one dimension and utilize a coded mask for resolution in the other. Their positioning accuracy is about an arc minute. The two remaining modules are made from the same materials but configured as a Kirkpatrick-Baez telescope with longer focal length that focuses in two dimensions. When pointed it refines the hybrid telescope’s arc minute positions to an arc second and provides larger effective area for spectral and temporal measurements. Above 10 keV the mirrors act as an imaging collimator with positioning capability. For short duration events this hybrid focusing/coded mask system is more sensitive and versatile than either a 2D coded mask or a 2D lobster-eye telescope. -
February 2020 Page 1 of 11
Newsletter Pretoria Centre ASSA February 2020 Page 1 of 11 NEWSLETTER FEBRUARY 2020 NEXT MEETING Venue: The auditorium behind the main building at Christian Brothers College (CBC), Mount Edmund, Pretoria Road, Silverton, Pretoria. Date and time: Wednesday 26 February at 19h15. Programme: ➢ Beginner’s Corner: “Discoveries by amateurs” by Michelle Ferreira. ➢ What’s Up: by Michael Poll. ----------------------------------- 10-minute break. Library will be open. -------------------------------- ➢ Main talk: TBA by e-mail to members. ➢ Socializing over tea/coffee and biscuits. The chairperson at the meeting will be Pierre Lourens. NEXT OBSERVING EVENING Friday 21 February from sunset onwards at the Pretoria Centre Observatory, which is also situated at CBC. Turn left immediately after entering the main gate and follow the road. TABLE OF CONTENTS Astronomy-related articles on the Internet 2 Report of observing evening on January 17th 2020 3 Astronomy basics: How Earth moves 3 Feature of the month: Does extraterrestrial life exist? 3 Observing: The Elephant’s Trunk 4 Chairperson’s report for the meeting on 22 January 2020 5 Summary of coming presentation on 26 February under “What's Up?” 6 NOTICE BOARD 7 Pretoria Centre committee 7 Astronomy-related images and video clips on the Internet 7 Determination of the Earth-Sun distance using the transit of Mercury on 11 8 November 2019 Newsletter Pretoria Centre ASSA February 2020 Page 2 of 11 Astronomy-related articles on the Internet These 2 outbound comets are likely from another solar system. https://earthsky.org/space/outbound-comets-are-likely-of-interstellar-origin? utm_source=EarthSky+News&utm_campaign=5b6df3e574- EMAIL_CAMPAIGN_2018_02_02_COPY_01&utm_medium=email&utm_term=0_c64394 5d79-5b6df3e574-394671529 Rigel in Orion is blue-white. -
Radio Sources in Low-Luminosity Active Galactic Nuclei
A&A 392, 53–82 (2002) Astronomy DOI: 10.1051/0004-6361:20020874 & c ESO 2002 Astrophysics Radio sources in low-luminosity active galactic nuclei III. “AGNs” in a distance-limited sample of “LLAGNs” N. M. Nagar1, H. Falcke2,A.S.Wilson3, and J. S. Ulvestad4 1 Arcetri Observatory, Largo E. Fermi 5, Florence 50125, Italy 2 Max-Planck-Institut f¨ur Radioastronomie, Auf dem H¨ugel 69, 53121 Bonn, Germany e-mail: [email protected] 3 Department of Astronomy, University of Maryland, College Park, MD 20742, USA Adjunct Astronomer, Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218, USA e-mail: [email protected] 4 National Radio Astronomy Observatory, PO Box 0, Socorro, NM 87801, USA e-mail: [email protected] Received 23 January 2002 / Accepted 6 June 2002 Abstract. This paper presents the results of a high resolution radio imaging survey of all known (96) low-luminosity active galactic nuclei (LLAGNs) at D ≤ 19 Mpc. We first report new 2 cm (150 mas resolution using the VLA) and 6 cm (2 mas resolution using the VLBA) radio observations of the previously unobserved nuclei in our samples and then present results on the complete survey. We find that almost half of all LINERs and low-luminosity Seyferts have flat-spectrum radio cores when observed at 150 mas resolution. Higher (2 mas) resolution observations of a flux-limited subsample have provided a 100% (16 of 16) detection rate of pc-scale radio cores, with implied brightness temperatures ∼>108 K. The five LLAGNs with the highest core radio fluxes also have pc-scale “jets”. -
Optical Blocking Performance of Ccds Developed for the X-Ray
Optical Blocking Performance of CCDs Developed for the X-ray Astronomy Satellite XRISM Hiroyuki Uchidaa,∗, Takaaki Tanakaa, Yuki Amanoa, Hiromichi Okona, Takeshi G. Tsurua, Hirofumi Nodae,f, Kiyoshi Hayashidae,f, Hironori Matsumotoe,f, Maho Hanaokae, Tomokage Yoneyamae, Koki Okazakie, Kazunori Asakurae, Shotaro Sakumae, Kengo Hattorie, Ayami Ishikurae, Hiroshi Nakajimah, Mariko Saitod, Kumiko K. Nobukawad,b, Hiroshi Tomidag, Yoshiaki Kanemaruc, Jin Satoc, Toshiyuki Takakic, Yuta Teradac, Koji Moric, Hikari Kashimurah, Takayoshi Kohmurai, Kouichi Haginoi, Hiroshi Murakamij, Shogo B. Kobayashik, Yusuke Nishiokac, Makoto Yamauchic, Isamu Hatsukadec, Takashi Sakol, Masayoshi Nobukawal, Yukino Urabem, Junko S. Hiragam, Hideki Uchiyaman, Kazutaka Yamaokao, Masanobu Ozakip, Tadayasu Dotanip,q, Hiroshi Tsunemie, Hisanori Suzukir, Shin-ichiro Takagir, Kenichi Sugimotor, Sho Atsumir, Fumiya Tanakar aDepartment of Physics, Kyoto University, Kitashirakawa Oiwake-cho, Sakyo, Kyoto, Kyoto 606-8502, Japan bDepartment of Physics, Kindai University, 3-4-1 Kowakae, Higashi-Osaka, Osaka 577-8502, Japan cFaculty of Engineering, University of Miyazaki, 1-1 Gakuen Kibanadai Nishi, Miyazaki 889-2192, Japan dDepartment of Physics, Faculty of Science, Nara Women’s University, Kitauoyanishi-machi, Nara, Nara 630-8506, Japan eDepartment of Earth and Space Science, Osaka University, 1-1 Machikaneyama-cho, Toyonaka, Osaka 560-0043, Japan fProject Research Center for Fundamental Sciences, Osaka University, 1-1 Machikaneyama-cho, Toyonaka, Osaka 560-0043, Japan gJapan -
Astronomy Magazine Special Issue
γ ι ζ γ δ α κ β κ ε γ β ρ ε ζ υ α φ ψ ω χ α π χ φ γ ω ο ι δ κ α ξ υ λ τ μ β α σ θ ε β σ δ γ ψ λ ω σ η ν θ Aι must-have for all stargazers η δ μ NEW EDITION! ζ λ β ε η κ NGC 6664 NGC 6539 ε τ μ NGC 6712 α υ δ ζ M26 ν NGC 6649 ψ Struve 2325 ζ ξ ATLAS χ α NGC 6604 ξ ο ν ν SCUTUM M16 of the γ SERP β NGC 6605 γ V450 ξ η υ η NGC 6645 M17 φ θ M18 ζ ρ ρ1 π Barnard 92 ο χ σ M25 M24 STARS M23 ν β κ All-in-one introduction ALL NEW MAPS WITH: to the night sky 42,000 more stars (87,000 plotted down to magnitude 8.5) AND 150+ more deep-sky objects (more than 1,200 total) The Eagle Nebula (M16) combines a dark nebula and a star cluster. In 100+ this intense region of star formation, “pillars” form at the boundaries spectacular between hot and cold gas. You’ll find this object on Map 14, a celestial portion of which lies above. photos PLUS: How to observe star clusters, nebulae, and galaxies AS2-CV0610.indd 1 6/10/10 4:17 PM NEW EDITION! AtlAs Tour the night sky of the The staff of Astronomy magazine decided to This atlas presents produce its first star atlas in 2006. -
Optical Design of Diffraction-Limited X-Ray Telescopes
Research Article Vol. 59, No. 16 / 1 June 2020 / Applied Optics 4901 Optical design of diffraction-limited x-ray telescopes Brandon D. Chalifoux, Ralf K. Heilmann, Herman L. Marshall, AND Mark L. Schattenburg* Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, USA *Corresponding author: [email protected] Received 11 March 2020; revised 21 April 2020; accepted 23 April 2020; posted 23 April 2020 (Doc. ID 392479); published 27 May 2020 Astronomical imaging with micro-arcsecond (µas) angular resolution could enable breakthrough scientific discov- eries. Previously proposed µas x-ray imager designs have been interferometers with limited effective collecting area. Here we describe x-ray telescopes achieving diffraction-limited performance over a wide energy band with large effective area, employing a nested-shell architecture with grazing-incidence mirrors, while matching the optical path lengths between all shells. We present two compact nested-shell Wolter Type 2 grazing-incidence telescope designs for diffraction-limited x-ray imaging: a micro-arcsecond telescope design with 14 µas angular resolution and 2.9 m2 of effective area at 5 keV photon energy (λ D 0.25 nm), and a smaller milli-arcsecond telescope design with 525 µas resolution and 645 cm2 effective area at 1 keV (λ D 1.24 nm). We describe how to match the optical path lengths between all shells in a compact mirror assembly and investigate chromatic and off-axis aberrations. Chromatic aberration results from total external reflection off of mirror surfaces, and we greatly mitigate its effects by slightly adjusting the path lengths in each mirror shell. -
An Extremely Powerful Long Lived Superluminal Ejection from the Black Hole MAXI J1820+070
An extremely powerful long lived superluminal ejection from the black hole MAXI J1820+070 J. S. Bright1, R. P. Fender1;2, S. E. Motta1, D. R. A. Williams1, J. Moldon3;4, R. M. Plotkin5;6, J. C. A. Miller-Jones6, I. Heywood1;7;8, E. Tremou9, R. Beswick4, G. R. Sivakoff10, S. Corbel9;11, D. A. H. Buckley12, J. Homan13;14;15, E. Gallo16, A. J. Tetarenko17, T. D. Russell18, D. A. Green19, D. Titterington19, P. A. Woudt2;20, R. P. Armstrong2;1;8, P. J. Groot21;2;12, A. Horesh22, A. J. van der Horst23;24, E. G. Kording¨ 21, V. A. McBride2;12;25, A. Rowlinson18;26 & R. A. M. J. Wijers18 1Astrophysics, Department of Physics, University of Oxford, Keble Road, Oxford, OX1 3RH, UK 2Department of Astronomy, University of Cape Town, Private Bag X3, Rondenbosch, 7701, South Africa 3Instituto de Astrof´ısica de Andaluc´ıa (IAA, CSIC), Glorieta de las Astronom´ıa, s/n, E-18008 Granada, Spain 4Jodrell Bank Centre for Astrophysics, The University of Manchester, M13 9PL, UK 5Department of Physics, University of Nevada, Reno, Nevada, 89557, USA 6International Centre for Radio Astronomy Research, Curtin University, GPO Box, U1987, Perth, WA 6845, Australia 7Department of Physics and Electronics, Rhodes University, PO Box 94, Grahamstown, 6140, South Africa 8South African Radio Astronomy Observatory (SARAO), 2 Fir Street, Observatory, Cape Town, 7925, South Africa 9AIM/CEA Paris-Saclay, Universite` Paris Diderot, CNRS, F-91191 Gif-sur-Yvette, France 1 10Department of Physics, CCIS 4-183, University of Alberta, Edmonton, AB, T6G 2E1, Canada 11Station de Radioastronomie de Nanc¸ay, Observatoire de Paris, PSL Research University, CNRS, Univ. -
Synapses of Active Galactic Nuclei: Comparing X-Ray and Optical Classifications Using Artificial Neural Networks?
A&A 567, A92 (2014) Astronomy DOI: 10.1051/0004-6361/201322592 & c ESO 2014 Astrophysics Synapses of active galactic nuclei: Comparing X-ray and optical classifications using artificial neural networks? O. González-Martín1;2;??, D. Díaz-González3, J. A. Acosta-Pulido1;2, J. Masegosa4, I. E. Papadakis5;6, J. M. Rodríguez-Espinosa1;2, I. Márquez4, and L. Hernández-García4 1 Instituto de Astrofísica de Canarias (IAC), C/Vía Láctea s/n, 38205 La Laguna, Spain e-mail: [email protected] 2 Departamento de Astrofísica, Universidad de La Laguna (ULL), 38205 La Laguna, Spain 3 Shidix Technologies, 38320, La Laguna, Spain 4 Instituto de Astrofísica de Andalucía, CSIC, C/ Glorieta de la Astronomía s/n, 18005 Granada, Spain 5 Physics Department, University of Crete, PO Box 2208, 710 03 Heraklion, Crete, Greece 6 IESL, Foundation for Research and Technology, 711 10 Heraklion, Crete, Greece Received 2 September 2013 / Accepted 3 April 2014 ABSTRACT Context. Many classes of active galactic nuclei (AGN) have been defined entirely through optical wavelengths, while the X-ray spectra have been very useful to investigate their inner regions. However, optical and X-ray results show many discrepancies that have not been fully understood yet. Aims. The main purpose of the present paper is to study the synapses (i.e., connections) between X-ray and optical AGN classifications. Methods. For the first time, the newly implemented efluxer task allowed us to analyse broad band X-ray spectra of a sample of emission-line nuclei without any prior spectral fitting. Our sample comprises 162 spectra observed with XMM-Newton/pn of 90 lo- cal emission line nuclei in the Palomar sample. -
New Type of Black Hole Detected in Massive Collision That Sent Gravitational Waves with a 'Bang'
New type of black hole detected in massive collision that sent gravitational waves with a 'bang' By Ashley Strickland, CNN Updated 1200 GMT (2000 HKT) September 2, 2020 <img alt="Galaxy NGC 4485 collided with its larger galactic neighbor NGC 4490 millions of years ago, leading to the creation of new stars seen in the right side of the image." class="media__image" src="//cdn.cnn.com/cnnnext/dam/assets/190516104725-ngc-4485-nasa-super-169.jpg"> Photos: Wonders of the universe Galaxy NGC 4485 collided with its larger galactic neighbor NGC 4490 millions of years ago, leading to the creation of new stars seen in the right side of the image. Hide Caption 98 of 195 <img alt="Astronomers developed a mosaic of the distant universe, called the Hubble Legacy Field, that documents 16 years of observations from the Hubble Space Telescope. The image contains 200,000 galaxies that stretch back through 13.3 billion years of time to just 500 million years after the Big Bang. " class="media__image" src="//cdn.cnn.com/cnnnext/dam/assets/190502151952-0502-wonders-of-the-universe-super-169.jpg"> Photos: Wonders of the universe Astronomers developed a mosaic of the distant universe, called the Hubble Legacy Field, that documents 16 years of observations from the Hubble Space Telescope. The image contains 200,000 galaxies that stretch back through 13.3 billion years of time to just 500 million years after the Big Bang. Hide Caption 99 of 195 <img alt="A ground-based telescope&amp;#39;s view of the Large Magellanic Cloud, a neighboring galaxy of our Milky Way.