The Dusty Universe
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Large Scale Structure in the Local Universe — the 2MASS Galaxy Catalog
Structure and Dynamics in the Local Universe CSIRO PUBLISHING Publications of the Astronomical Society of Australia, 2004, 21, 396–403 www.publish.csiro.au/journals/pasa Large Scale Structure in the Local Universe — The 2MASS Galaxy Catalog Thomas JarrettA A Infrared Processing and Analysis Center, MS 100-22, California Institute of Technology, Pasadena, CA 91125, USA. Email: [email protected] Received 2004 May 3, accepted 2004 October 12 Abstract: Using twin ground-based telescopes, the Two-Micron All Sky Survey (2MASS) scanned both equatorial hemispheres, detecting more than 500 million stars and resolving more than 1.5 million galaxies in the near-infrared (1–2.2 µm) bands. The Extended Source Catalog (XSC) embodies both photometric and astrometric whole sky uniformity, revealing large scale structures in the local Universe and extending our view into the Milky Way’s dust-obscured ‘Zone of Avoidance’. The XSC represents a uniquely unbiased sample of nearby galaxies, particularly sensitive to the underlying, dominant, stellar mass component of galaxies. The basic properties of the XSC, including photometric sensitivity, source counts, and spatial distribution, are presented here. Finally, we employ a photometric redshift technique to add depth to the spatial maps, reconstructing the cosmic web of superclusters spanning the sky. Keywords: general: galaxies — fundamental parameters: infrared — galaxies: clusters — surveys: astronomical 1 Introduction 2003), distance indicators (e.g. Karachentsev et al. 2002), Our understanding of the origin and evolution of the Uni- angular correlation functions (e.g. Maller et al. 2003a), and verse has been fundamentally transformed with seminal the dipole of the local Universe (e.g. -
Arxiv:2012.09981V1 [Astro-Ph.SR] 17 Dec 2020 2 O
Contrib. Astron. Obs. Skalnat´ePleso XX, 1 { 20, (2020) DOI: to be assigned later Flare stars in nearby Galactic open clusters based on TESS data Olga Maryeva1;2, Kamil Bicz3, Caiyun Xia4, Martina Baratella5, Patrik Cechvalaˇ 6 and Krisztian Vida7 1 Astronomical Institute of the Czech Academy of Sciences 251 65 Ondˇrejov,The Czech Republic(E-mail: [email protected]) 2 Lomonosov Moscow State University, Sternberg Astronomical Institute, Universitetsky pr. 13, 119234, Moscow, Russia 3 Astronomical Institute, University of Wroc law, Kopernika 11, 51-622 Wroc law, Poland 4 Department of Theoretical Physics and Astrophysics, Faculty of Science, Masaryk University, Kotl´aˇrsk´a2, 611 37 Brno, Czech Republic 5 Dipartimento di Fisica e Astronomia Galileo Galilei, Vicolo Osservatorio 3, 35122, Padova, Italy, (E-mail: [email protected]) 6 Department of Astronomy, Physics of the Earth and Meteorology, Faculty of Mathematics, Physics and Informatics, Comenius University in Bratislava, Mlynsk´adolina F-2, 842 48 Bratislava, Slovakia 7 Konkoly Observatory, Research Centre for Astronomy and Earth Sciences, H-1121 Budapest, Konkoly Thege Mikl´os´ut15-17, Hungary Received: September ??, 2020; Accepted: ????????? ??, 2020 Abstract. The study is devoted to search for flare stars among confirmed members of Galactic open clusters using high-cadence photometry from TESS mission. We analyzed 957 high-cadence light curves of members from 136 open clusters. As a result, 56 flare stars were found, among them 8 hot B-A type ob- jects. Of all flares, 63 % were detected in sample of cool stars (Teff < 5000 K), and 29 % { in stars of spectral type G, while 23 % in K-type stars and ap- proximately 34% of all detected flares are in M-type stars. -
Observations of New Galaxies in the Zone of Avoidance Using the Arecibo Radio Telescope R
Observations of new galaxies in the Zone of Avoidance using the Arecibo Radio Telescope R. Birdsall, N. Ballering, A. Beardsley, L. Hunt, S. Stanimirovic (Mentor) University of Wisconsin Astronomy Department Abstract: As part of an undergraduate research techniques course, we detected the neutral hydrogen (HI) spectrum of the galaxy SPITZER192404+145632. This galaxy is located in the Zone of Avoidance (ZoA), a region of the large-scale distribution of galaxies that is obscured by our own galactic disk. Using the Arecibo Observatory*, we were able to confirm the infrared detection made by 9 11 Marleau et al. (2008). We find a redshift of z = 0.019, an HI mass of MHI = 1.02 x 10 Mo, and dynamical mass of MT ≈ 3.9 x 10 Mo. Motivation: The Zone of avoidance (ZoA) is located in the night sky in Observations: Analysis: Using the observed spectrum, we calculate the systemic the direction of our galactic disk. Observations of galaxies at optical We observed remotely velocity, distance, rotational velocity, HI mass, and dynamical mass of wavelengths are extremely difficult in this region because of absorption of on October 16, 2008, SPITZER192404+145632. The systemic velocity is found by simply light by the dust in the disk of the Milky Way. Therefore, fewer objects using position switch- evaluating the midpoint velocity of the spectrum. We found vsys = 5800 have been found in the ZoA than in other regions of space (see Figure 1). ing (ON/OFF) observa- km/s. This corresponds to a redshift of z = 0.019. The distance to the Observations in the ZoA with very sensitive infrared and radio telescopes, tions with the L-wide galaxy is determined using Hubble’s Law: present an opportunity for astronomers to discover new galaxies, as receiver of the Arecibo waves at these wavelengths are not absorbed by dust. -
OBSERVATIONS in the ZONE of AVOIDANCE USING ARECIBO OBSERVATORY R.Birdsall, N.Ballering, A.Beardsley, L.Hunt, R.Wilson, S.Stanim
OBSERVATIONS IN THE ZONE OF AVOIDANCE USING ARECIBO OBSERVATORY R.Birdsall, N.Ballering, A.Beardsley, L.Hunt, R.Wilson, S.Stanimi 1. Abstract The Zone of Avoidance is a relatively unknown region of space that lies on the other side of our galactic disk. Previous observations made by other collaborators such as Galactic Legacy Infrared Mid-Plane Survey Extraordinaire (GLIMPSE) and MIPS Galactic Plane Survey (MIPSGAL) which surveyed the Zone of Avoidance in the infrared spectrum with the Spitzer Space Telescope.[1] Our team decided to focus on target objects observed by the (GLIMPSE) and(MIPSGAL). These two collaborations identified twenty five new objects in the Infrared Spectrum that had the properties of galaxy like objects. For that reason, we used the Arecibo Radio Observatory in the hopes of detecting the radio signal of neutral hydrogen and identifying these objects. This piece focuses on SP192404+1456 2. Zone of Avoidance The Zone of Avoidance is a interesting region of the night sky because very little is known about what occupies that space. The ZOA is the region of the sky that lies beyond in the direction of the Milky Way galactic center. Thus EM radiation sources from the ZOA must make its way through the galactic disk. This makes detection of these galaxies difficult to near impossible. Both GLIMPSE and MIPSGAL where able to detect twenty-five obscure objects in the IR part of the spectrum, but where unable to verify exact source parameters. 1 2 OBSERVATIONS IN THE ZONE OF AVOIDANCE USING ARECIBO OBSERVATORY [2] In Figure 1. we see a spacial map of previous galactic survey's. -
J Pionisrskis Lata Eieitronorriii W Toruniu
j Pionisrskis lata EiEitronorriii w Toruniu j Aktywność magnetyczna Słońca j Towarzyskie pJaneioidy Pawilon teleskopu Schmidta-Cassegraina w Piwnicach od strony południowo-zachodniej stu Mikołaja Kopernika prawie w komplecie — październik 2005 r. Szanowni i Drodzy Czytelnicy, Prenumeratorów naszego czasopisma spotyka w tym miesiącu nagroda — wszyscy otrzymują dwa zeszyty „ Uranii-Postępów Astronomii”. Jeden, to regularny zeszyt noszący datę marzec-kwiecień 2006 r., a drugi to bonus — specjalne wydanie „ Uranii”. Zawiera ono referaty wygłoszone na angielskojęzycznych sesjach w czasie Zjazdu Polskiego Towarzystwa fot. bauksza-WiiniewsltaA. Astronomicznego we wrześniu 2005 r. we Wrocławiu. Skupiają się one wokół dwóch zagadnień: gwiazd pulsujących (w tym astrosejsmologii) i fizyki Słońca. Autorzy są znakomitymi specjalistami tych dziedzin, a całość stanowi doskonały obraz problemów współczesnych astronomii w tych tematach. Komitet Organizacyjny Zjazdu znalazł pieniądze na wydanie materiałów zjazdowych i zrobienie prezentu naszym najwierniejszym Czytelnikom, za co jesteśmy mu bardzo wdzięczni. Nasz zwykły, polskojęzyczny nr 2 (722) otwiera, kreślone piórem niżej podpisanego, wspomnienie pionierskich lat astronomii w Toruniu, rodzącej się wraz z powstaniem Uniwersytetu Mikołaja Kopernika. Uniwersytet ten świętował w 2005 r. swoje 60-łecie. Uznaliśmy, że wypada też przypomnieć z tej okazji, jak to się narodził i rósł toruński ośrodek astronomiczny, który dzisiaj nosi miano Centrum Astronomii UMK. Następnie naszą uwagę kierujemy na najważniejszy obiekt nieba — Słońce. O badaniu naszej dziennej gwiazdy i procesach zachodzących w jej zewnętrznych warstwach opowiada hełiofizyk Paweł Rudawy z Wrocławia. Analizuje głównie zjawiska zachodzące między polem magnetycznym a plazmą słoneczną. Oddziaływania te leżą u podstaw zjawisk tzw. aktywności słonecznej, które są pilnie obserwowane nie tylko przez profesjonalnych astronomów, ale też i przez tysiące miłośników astronomii. -
A Basic Requirement for Studying the Heavens Is Determining Where In
Abasic requirement for studying the heavens is determining where in the sky things are. To specify sky positions, astronomers have developed several coordinate systems. Each uses a coordinate grid projected on to the celestial sphere, in analogy to the geographic coordinate system used on the surface of the Earth. The coordinate systems differ only in their choice of the fundamental plane, which divides the sky into two equal hemispheres along a great circle (the fundamental plane of the geographic system is the Earth's equator) . Each coordinate system is named for its choice of fundamental plane. The equatorial coordinate system is probably the most widely used celestial coordinate system. It is also the one most closely related to the geographic coordinate system, because they use the same fun damental plane and the same poles. The projection of the Earth's equator onto the celestial sphere is called the celestial equator. Similarly, projecting the geographic poles on to the celest ial sphere defines the north and south celestial poles. However, there is an important difference between the equatorial and geographic coordinate systems: the geographic system is fixed to the Earth; it rotates as the Earth does . The equatorial system is fixed to the stars, so it appears to rotate across the sky with the stars, but of course it's really the Earth rotating under the fixed sky. The latitudinal (latitude-like) angle of the equatorial system is called declination (Dec for short) . It measures the angle of an object above or below the celestial equator. The longitud inal angle is called the right ascension (RA for short). -
Predicting Structures in the Zone of Avoidance
Mon. Not. R. Astron. Soc. 000, 1–11 (2017) Printed 8 October 2018 (MN LATEX style file v2.2) Predicting Structures in the Zone of Avoidance Jenny G. Sorce1,2⋆, Matthew Colless3, Renee´ C. Kraan-Korteweg4, Stefan Gottlober¨ 2 1Universit´ede Strasbourg, CNRS, Observatoire astronomique de Strasbourg, UMR 7550, F-67000 Strasbourg, France 2Leibniz-Institut f¨ur Astrophysik, 14482 Potsdam, Germany 3Research School of Astronomy and Astrophysics, Australian National University, Canberra, ACT 2611, Australia 4Department of Astronomy, University of Cape Town, 7700 Rondebosch, South Africa ABSTRACT The Zone of Avoidance (ZOA), whose emptiness is an artifact of our Galaxy dust, has been challenging observers as well as theorists for many years. Multiple attempts have been made on the observational side to map this region in order to better understand the local flows. On the the- oretical side, however, this region is often simply statistically populated with structures but no real attempt has been made to confront theoretical and observed matter distributions. This paper takes a step forward using constrained realizations of the local Universe shown to be perfect substitutes of local Universe-like simulations for smoothed high density peak studies. Far from generating com- pletely ‘random’ structures in the ZOA, the reconstruction technique arranges matter according to the surrounding environment of this region. More precisely, the mean distributions of structures in a series of constrained and random realizations differ: while densities annihilate each other when averaging over 200 random realizations, structures persist when summing 200 constrained realiza- tions. The probability distribution function of ZOA grid cells to be highly overdense is a Gaussian with a 15% mean in the random case, while that of the constrained case exhibits large tails. -
Mapping the Hidden Universe: the Galaxy Distribution in the Zone of Avoidance
Publ. Astron. Soc. Aust., 2000, 17, 6–12. Mapping the Hidden Universe: The Galaxy Distribution in the Zone of Avoidance Renee C. Kraan-Korteweg1 and Sebastian Juraszek2,3 1Departamento de Astronoma, Universidad de Guanajuato, Apartado Postal 144, Guanajuato GTO 36000, Mexico [email protected] 2School of Physics, University of Sydney, NSW 2006, Australia 3ATNF, CSIRO, PO Box 76, Epping, NSW 2121, Australia [email protected] Received 1999 August 26, accepted 1999 October 26 Abstract: Due to the foreground extinction of the Milky Way, galaxies become increasingly faint as they approach the Galactic Equator creating a ‘zone of avoidance’ (ZOA) in the distribution of optically visible galaxies of about 25%. A ‘whole-sky’ map of galaxies is essential, however, for understanding the dynamics in our local Universe, in particular the peculiar velocity of the Local Group with respect to the Cosmic Microwave Background and velocity ow elds such as in the Great Attractor (GA) region. The current status of deep optical galaxy searches behind the Milky Way and their completeness as a function of foreground extinction will be reviewed. It has been shown that these surveys—which in the mean time cover the whole ZOA (Figure 2)—result in a considerable reduction of the ZOA from extinction levels of m m AB =10 (Figure 1) to AB =30 (Figure 3). In the remaining, optically opaque ZOA, systematic HI surveys are powerful in uncovering galaxies, as is demonstrated for the GA region with data from the full sensitivity Parkes Multibeam HI survey (300 ` 332, |b|55, Figure 4). Keywords: zone of avoidance — surveys — ISM: dust, extinction — large-scale structure of universe 1 Introduction presented in an Aito equal-area projection centred on the Galactic plane. -
Stellar Chromospheric Activity and Age Relation from Open Clusters in the LAMOST Survey
Publications 12-12-2019 Stellar Chromospheric Activity and Age Relation from Open Clusters in the LAMOST Survey Jiajun Zhang University of Chinese Academy of Sciences, Terry Oswalt Embry-Riddle Aeronautical University, [email protected] Jingkun Zhao University of Chinese Academy of Sciences, Xiangsong Fang National Astronomical Observatories Gang Zhao Chinese Academy of Sciences, See next page for additional authors Follow this and additional works at: https://commons.erau.edu/publication Part of the Stars, Interstellar Medium and the Galaxy Commons Scholarly Commons Citation Zhang, J., Oswalt, T., Zhao, J., Fang, X., Zhao, G., Liang, X., Ye, X., & Zhong, J. (2019). Stellar Chromospheric Activity and Age Relation from Open Clusters in the LAMOST Survey. The Astrophysical Journal, 887(1). Retrieved from https://commons.erau.edu/publication/1383 This Article is brought to you for free and open access by Scholarly Commons. It has been accepted for inclusion in Publications by an authorized administrator of Scholarly Commons. For more information, please contact [email protected]. Authors Jiajun Zhang, Terry Oswalt, Jingkun Zhao, Xiangsong Fang, Gang Zhao, Xilong Liang, Xianhao Ye, and Jing Zhong This article is available at Scholarly Commons: https://commons.erau.edu/publication/1383 Draft version October 1, 2019 Typeset using LATEX default style in AASTeX62 Stellar chromospheric activity and age relation from open clusters in the LAMOST Survey Jiajun Zhang,1, 2 Jingkun Zhao,1 Terry D. Oswalt,3 Xiangsong Fang,4, 5 Gang Zhao,1, 2 Xilong Liang,1, 2 Xianhao Ye,1, 2 and Jing Zhong6 1Key Laboratory of Optical Astronomy, National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012, China. -
A Kinematic Confirmation of the Hidden Vela Supercluster
MNRAS 000,1{6 (2019) Preprint 20 September 2019 Compiled using MNRAS LATEX style file v3.0 A kinematic confirmation of the hidden Vela supercluster H´el`ene M. Courtois1?, Ren´ee C. Kraan-Korteweg2, Alexandra Dupuy1, Romain Graziani1 and Noam I. Libeskind,1;3 1University of Lyon, UCB Lyon 1, CNRS/IN2P3, IP2I Lyon, France 2Department of Astronomy, University of Cape Town, Private Bag X3, 7701 Rondebosch, South Africa 3Leibniz-Institut fur¨ Astrophysik Potsdam (AIP), An der Sternwarte 16, D-14482 Potsdam, Germany Accepted....... ; ABSTRACT The universe region obscured by the Milky Way is very large and only future blind large HI redshift, and targeted peculiar surveys on the outer borders will determine how much mass is hidden there. Meanwhile, we apply for the first time two independent techniques to the galaxy peculiar velocity catalog CosmicF lows−3 in order to explore for the kinematic signature of a specific large-scale structure hidden behind this zone : the Vela supercluster at cz ∼ 18; 000,km s−1 . Using the gravitational velocity and density contrast fields, we find excellent agreement when comparing our results to the Vela object as traced in redshift space. The article provides the first kinematic evidence of a major mass concentration (knot of the Cosmic Web) located in the direction behind Vela constellation, pin-pointing that the Zone of Avoidance should be surveyed in detail in the future . Key words: large-scale structure of Universe 1 INTRODUCTION (sgl; sgb ∼ 173◦; −47◦)(Kraan-Korteweg et al.(2017, 2015), henceforth KK17a,b). A significant bulk flow residual was revealed in 2014 in the Radial peculiar velocities can be modeled using the analysis of the 6dF peculiar velocity survey based on 8,885 Wiener filter methodology Zaroubi et al.(1999); Hoffman galaxies in the southern hemisphere within a volume cz (2009); Courtois et al.(2012), recently re-vamped by data ≤ 16; 000 km s−1 Springob et al.(2014). -
Characterising Open Clusters in the Solar Neighbourhood with the Tycho-Gaia Astrometric Solution? T
A&A 615, A49 (2018) Astronomy https://doi.org/10.1051/0004-6361/201731251 & © ESO 2018 Astrophysics Characterising open clusters in the solar neighbourhood with the Tycho-Gaia Astrometric Solution? T. Cantat-Gaudin1, A. Vallenari1, R. Sordo1, F. Pensabene1,2, A. Krone-Martins3, A. Moitinho3, C. Jordi4, L. Casamiquela4, L. Balaguer-Núnez4, C. Soubiran5, and N. Brouillet5 1 INAF-Osservatorio Astronomico di Padova, vicolo Osservatorio 5, 35122 Padova, Italy e-mail: [email protected] 2 Dipartimento di Fisica e Astronomia, Università di Padova, vicolo Osservatorio 3, 35122 Padova, Italy 3 SIM, Faculdade de Ciências, Universidade de Lisboa, Ed. C8, Campo Grande, 1749-016 Lisboa, Portugal 4 Institut de Ciències del Cosmos, Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain 5 Laboratoire d’Astrophysique de Bordeaux, Univ. Bordeaux, CNRS, UMR 5804, 33615 Pessac, France Received 26 May 2017 / Accepted 29 January 2018 ABSTRACT Context. The Tycho-Gaia Astrometric Solution (TGAS) subset of the first Gaia catalogue contains an unprecedented sample of proper motions and parallaxes for two million stars brighter than G 12 mag. Aims. We take advantage of the full astrometric solution available∼ for those stars to identify the members of known open clusters and compute mean cluster parameters using either TGAS or the fourth U.S. Naval Observatory CCD Astrograph Catalog (UCAC4) proper motions, and TGAS parallaxes. Methods. We apply an unsupervised membership assignment procedure to select high probability cluster members, we use a Bayesian/Markov Chain Monte Carlo technique to fit stellar isochrones to the observed 2MASS JHKS magnitudes of the member stars and derive cluster parameters (age, metallicity, extinction, distance modulus), and we combine TGAS data with spectroscopic radial velocities to compute full Galactic orbits. -
Serendipitious 2MASS Discoveries Near the Galactic Plane
Serendipitous 2MASS Discoveries Near the Galactic Plane: A Spiral Galaxy and Two Globular Clusters Robert L. Hurt, Tom H. Jarrett, J. Davy Kirkpatrick, Roc M. Cutri Infrared Processing & Analysis Center, MS 100-22, California Institute of Technology, Jet Propulsion Laboratory, Pasadena, CA 91125 [email protected], [email protected], [email protected], [email protected] Stephen E. Schneider, Mike Skrutskie Astronomy Program, University of Massachusetts, Amherst, MA 01003 [email protected], [email protected] Willem van Driel United Scientifique Nançay, Obs. de Paris–Meudon, Meudon Cedex, CA 92195, France [email protected] Abstract We present the basic properties of three objects near the Galactic Plane—a large galaxy and two candidate globular clusters—discovered in the Two Micron All Sky Survey (2MASS) dataset. All were noted during spot-checks of the data during 2MASS quality assurance reviews. The galaxy is a late-type spiral galaxy (Sc–Sd), ~11 Mpc distant, at l = 236.82°, b = -1.86°. From its observed angular extent of 6.3' in the near infrared, we estimate an extinction-corrected optical diameter of ~9.5', making it larger than most Messier galaxies. The candidate globular clusters are ~2–3’ in extent and are hidden optically behind foreground extinctions of Av ~18–21 mag at l ~ 10°, b ~ 0°. These chance discoveries were not the result of any kind of systematic search but they do hint at the wealth of obscured sources of all kinds, many previously unknown, that are in the 2MASS dataset. Key words: galaxies: photometry—galaxies: spiral—(Galaxy:) globular clusters: general—surveys—infrared radiation 1.