Class II Methanol Masers in Star Formation Regions
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THE 1000 BRIGHTEST HIPASS GALAXIES: H I PROPERTIES B
The Astronomical Journal, 128:16–46, 2004 July A # 2004. The American Astronomical Society. All rights reserved. Printed in U.S.A. THE 1000 BRIGHTEST HIPASS GALAXIES: H i PROPERTIES B. S. Koribalski,1 L. Staveley-Smith,1 V. A. Kilborn,1, 2 S. D. Ryder,3 R. C. Kraan-Korteweg,4 E. V. Ryan-Weber,1, 5 R. D. Ekers,1 H. Jerjen,6 P. A. Henning,7 M. E. Putman,8 M. A. Zwaan,5, 9 W. J. G. de Blok,1,10 M. R. Calabretta,1 M. J. Disney,10 R. F. Minchin,10 R. Bhathal,11 P. J. Boyce,10 M. J. Drinkwater,12 K. C. Freeman,6 B. K. Gibson,2 A. J. Green,13 R. F. Haynes,1 S. Juraszek,13 M. J. Kesteven,1 P. M. Knezek,14 S. Mader,1 M. Marquarding,1 M. Meyer,5 J. R. Mould,15 T. Oosterloo,16 J. O’Brien,1,6 R. M. Price,7 E. M. Sadler,13 A. Schro¨der,17 I. M. Stewart,17 F. Stootman,11 M. Waugh,1, 5 B. E. Warren,1, 6 R. L. Webster,5 and A. E. Wright1 Received 2002 October 30; accepted 2004 April 7 ABSTRACT We present the HIPASS Bright Galaxy Catalog (BGC), which contains the 1000 H i brightest galaxies in the southern sky as obtained from the H i Parkes All-Sky Survey (HIPASS). The selection of the brightest sources is basedontheirHi peak flux density (Speak k116 mJy) as measured from the spatially integrated HIPASS spectrum. 7 ; 10 The derived H i masses range from 10 to 4 10 M . -
Arxiv:2011.00929V1 [Astro-Ph.GA] 2 Nov 2020 of a Real Age Spread
Astronomy & Astrophysics manuscript no. paper ©ESO 2020 November 3, 2020 Multiple populations of Hβ emission line stars in the Large Magellanic Cloud cluster NGC 1971 Andrés E. Piatti1; 2? 1 Instituto Interdisciplinario de Ciencias Básicas (ICB), CONICET-UNCUYO, Padre J. Contreras 1300, M5502JMA, Mendoza, Argentina; 2 Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Godoy Cruz 2290, C1425FQB, Buenos Aires, Argentina Received / Accepted ABSTRACT We revisited the young Large Magellanic Cloud star cluster NGC 1971 with the aim of providing additional clues to our understanding of its observed extended Main Sequence turnoff (eMSTO), a feature common seen in young stars clusters,which was recently argued to be caused by a real age spread similar to the cluster age (∼160 Myr). We combined accurate Washington and Strömgren photometry of high membership probability stars to explore the nature of such an eMSTO. From different ad hoc defined pseudo colors we found that bluer and redder stars distributed throughout the eMSTO do not show any inhomogeneities of light and heavy-element abundances. These ’blue’ and ’red’ stars split into two clearly different groups only when the Washington M magnitudes are employed, which delimites the number of spectral features responsible for the appearance of the eMSTO. We speculate that Be stars populate the eMSTO of NGC 1971 because: i) Hβ contributes to the M passband; ii) Hβ emissions are common features of Be stars and; iii) Washington M and T1 magnitudes show a tight correlation; the latter measuring the observed contribution of Hα emission line in Be stars, which in turn correlates with Hβ emissions. -
Arxiv:2009.04090V2 [Astro-Ph.GA] 14 Sep 2020
Research in Astronomy and Astrophysics manuscript no. (LATEX: tikhonov˙Dorado.tex; printed on September 15, 2020; 1:01) Distance to the Dorado galaxy group N.A. Tikhonov1, O.A. Galazutdinova1 Special Astrophysical Observatory, Nizhnij Arkhyz, Karachai-Cherkessian Republic, Russia 369167; [email protected] Abstract Based on the archival images of the Hubble Space Telescope, stellar photometry of the brightest galaxies of the Dorado group:NGC 1433, NGC1533,NGC1566and NGC1672 was carried out. Red giants were found on the obtained CM diagrams and distances to the galaxies were measured using the TRGB method. The obtained values: 14.2±1.2, 15.1±0.9, 14.9 ± 1.0 and 15.9 ± 0.9 Mpc, show that all the named galaxies are located approximately at the same distances and form a scattered group with an average distance D = 15.0 Mpc. It was found that blue and red supergiants are visible in the hydrogen arm between the galaxies NGC1533 and IC2038, and form a ring structure in the lenticular galaxy NGC1533, at a distance of 3.6 kpc from the center. The high metallicity of these stars (Z = 0.02) indicates their origin from NGC1533 gas. Key words: groups of galaxies, Dorado group, stellar photometry of galaxies: TRGB- method, distances to galaxies, galaxies NGC1433, NGC 1533, NGC1566, NGC1672 1 INTRODUCTION arXiv:2009.04090v2 [astro-ph.GA] 14 Sep 2020 A concentration of galaxies of different types and luminosities can be observed in the southern constella- tion Dorado. Among them, Shobbrook (1966) identified 11 galaxies, which, in his opinion, constituted one group, which he called “Dorado”. -
Stsci Newsletter: 1991 Volume 008 Issue 03
SPACE 'fEIFSCOPE SOENCE ...______._.INSTITUIE Operated for NASA by AURA November 1991 Vol. 8No. 3 HIGHLIGHTS OF THIS ISSUE: HSTSCIENCE HIGHLIGHTS WF/PC OBSERVATIONS OF THE STELLAR O NEW SCIENCE RESULTS ON M87, CRAB PULSAR CUSP IN M87 O COSTAR PROGRESSING WELL The photograph on the left shows one of a set of images of the central regions of the giant ellipti O ANSWERS TO YOUR QUESTIONS ABOUT HST DATA cal galaxy M87, obtained in June 1991 withHSI's Wide Field and Planetary Camera {WF/PC). 0 CYCLE 2 PEER REVIEW UNDERWAY Analysis of these images has revealed a stellar cusp in the core of M87, consistent with the pres ence of a massive black hole in its nucleus. A combined approach of image deconvolution and modelling has made it possible to investigate the starlight distribution in M87 down to a limiting radius of about 0'.'04 from the nucleus (or about 3 pc from the nucleus if the Virgo cluster is at 16 Mpc). The results show that the central struc ture of M87 can be described by three compo nents: a power-law starlight profile with an r·114 slope which continues unabated into the center, an unresolved central point source, and optical coun terparts of the jet knots identified by VLBI obser vations. In both the V- and /-band Planetary Camera images, the stellar cusp is consistent with the black-hole model proposed for M87 by Young et al. in 1978; in this model, there is a central mas sive object of about 3 x 109 Me. -
Arxiv:1704.06321V1 [Astro-Ph.GA] 20 Apr 2017
Accepted for Publication in the Astrophysical Journal Preprint typeset using LATEX style emulateapj v. 12/16/11 THE HIERARCHICAL DISTRIBUTION OF THE YOUNG STELLAR CLUSTERS IN SIX LOCAL STAR FORMING GALAXIES K. Grasha1, D. Calzetti1, A. Adamo2, H. Kim3, B.G. Elmegreen4, D.A. Gouliermis5,6, D.A. Dale7, M. Fumagalli8, E.K. Grebel9, K.E. Johnson10, L. Kahre11, R.C. Kennicutt12, M. Messa2, A. Pellerin13, J.E. Ryon14, L.J. Smith15, F. Shabani8, D. Thilker16, L. Ubeda14 Accepted for Publication in the Astrophysical Journal ABSTRACT We present a study of the hierarchical clustering of the young stellar clusters in six local (3{15 Mpc) star-forming galaxies using Hubble Space Telescope broad band WFC3/UVIS UV and optical images from the Treasury Program LEGUS (Legacy ExtraGalactic UV Survey). We have identified 3685 likely clusters and associations, each visually classified by their morphology, and we use the angular two-point correlation function to study the clustering of these stellar systems. We find that the spatial distribution of the young clusters and associations are clustered with respect to each other, forming large, unbound hierarchical star-forming complexes that are in general very young. The strength of the clustering decreases with increasing age of the star clusters and stellar associations, becoming more homogeneously distributed after ∼40{60 Myr and on scales larger than a few hundred parsecs. In all galaxies, the associations exhibit a global behavior that is distinct and more strongly correlated from compact clusters. Thus, populations of clusters are more evolved than associations in terms of their spatial distribution, traveling significantly from their birth site within a few tens of Myr whereas associations show evidence of disruption occurring very quickly after their formation. -
Gas and Dust in the Magellanic Clouds
Gas and dust in the Magellanic clouds A Thesis Submitted for the Award of the Degree of Doctor of Philosophy in Physics To Mangalore University by Ananta Charan Pradhan Under the Supervision of Prof. Jayant Murthy Indian Institute of Astrophysics Bangalore - 560 034 India April 2011 Declaration of Authorship I hereby declare that the matter contained in this thesis is the result of the inves- tigations carried out by me at Indian Institute of Astrophysics, Bangalore, under the supervision of Professor Jayant Murthy. This work has not been submitted for the award of any degree, diploma, associateship, fellowship, etc. of any university or institute. Signed: Date: ii Certificate This is to certify that the thesis entitled ‘Gas and Dust in the Magellanic clouds’ submitted to the Mangalore University by Mr. Ananta Charan Pradhan for the award of the degree of Doctor of Philosophy in the faculty of Science, is based on the results of the investigations carried out by him under my supervi- sion and guidance, at Indian Institute of Astrophysics. This thesis has not been submitted for the award of any degree, diploma, associateship, fellowship, etc. of any university or institute. Signed: Date: iii Dedicated to my parents ========================================= Sri. Pandab Pradhan and Smt. Kanak Pradhan ========================================= Acknowledgements It has been a pleasure to work under Prof. Jayant Murthy. I am grateful to him for giving me full freedom in research and for his guidance and attention throughout my doctoral work inspite of his hectic schedules. I am indebted to him for his patience in countless reviews and for his contribution of time and energy as my guide in this project. -
Download the 2016 Spring Deep-Sky Challenge
Deep-sky Challenge 2016 Spring Southern Star Party Explore the Local Group Bonnievale, South Africa Hello! And thanks for taking up the challenge at this SSP! The theme for this Challenge is Galaxies of the Local Group. I’ve written up some notes about galaxies & galaxy clusters (pp 3 & 4 of this document). Johan Brink Peter Harvey Late-October is prime time for galaxy viewing, and you’ll be exploring the James Smith best the sky has to offer. All the objects are visible in binoculars, just make sure you’re properly dark adapted to get the best view. Galaxy viewing starts right after sunset, when the centre of our own Milky Way is visible low in the west. The edge of our spiral disk is draped along the horizon, from Carina in the south to Cygnus in the north. As the night progresses the action turns north- and east-ward as Orion rises, drawing the Milky Way up with it. Before daybreak, the Milky Way spans from Perseus and Auriga in the north to Crux in the South. Meanwhile, the Large and Small Magellanic Clouds are in pole position for observing. The SMC is perfectly placed at the start of the evening (it culminates at 21:00 on November 30), while the LMC rises throughout the course of the night. Many hundreds of deep-sky objects are on display in the two Clouds, so come prepared! Soon after nightfall, the rich galactic fields of Sculptor and Grus are in view. Gems like Caroline’s Galaxy (NGC 253), the Black-Bottomed Galaxy (NGC 247), the Sculptor Pinwheel (NGC 300), and the String of Pearls (NGC 55) are keen to be viewed. -
Dorado and Its Member Galaxies II: a UVIT Picture of the NGC 1533 Substructure
J. Astrophys. Astr. (2021) 42:31 Ó Indian Academy of Sciences https://doi.org/10.1007/s12036-021-09690-xSadhana(0123456789().,-volV)FT3](0123456789().,-volV) SCIENCE RESULTS Dorado and its member galaxies II: A UVIT picture of the NGC 1533 substructure R. RAMPAZZO1,2,* , P. MAZZEI2, A. MARINO2, L. BIANCHI3, S. CIROI4, E. V. HELD2, E. IODICE5, J. POSTMA6, E. RYAN-WEBER7, M. SPAVONE5 and M. USLENGHI8 1INAF Osservatorio Astrofisico di Asiago, Via Osservatorio 8, 36012 Asiago, Italy. 2INAF Osservatorio Astronomico di Padova, Vicolo dell’Osservatorio 5, 35122 Padua, Italy. 3Department of Physics and Astronomy, The Johns Hopkins University, 3400 N. Charles St., Baltimore, MD 21218, USA. 4Department of Physics and Astronomy, University of Padova, Vicolo dell’Osservatorio 3, 35122 Padua, Italy. 5INAF-Osservatorio Astronomico di Capodimonte, Salita Moiariello 16, 80131 Naples, Italy. 6University of Calgary, 2500 University Drive NW, Calgary, Alberta, Canada. 7Centre for Astrophysics and Supercomputing, Swinburne University of Technology, Hawthorn, VIC 3122, Australia. 8INAF-IASF, Via A. Curti, 12, 20133 Milan, Italy. *Corresponding Author. E-mail: [email protected] MS received 30 October 2020; accepted 17 December 2020 Abstract. Dorado is a nearby (17.69 Mpc) strongly evolving galaxy group in the Southern Hemisphere. We are investigating the star formation in this group. This paper provides a FUV imaging of NGC 1533, IC 2038 and IC 2039, which form a substructure, south west of the Dorado group barycentre. FUV CaF2-1 UVIT-Astrosat images enrich our knowledge of the system provided by GALEX. In conjunction with deep optical wide-field, narrow-band Ha and 21-cm radio images we search for signatures of the interaction mechanisms looking in the FUV morphologies and derive the star formation rate. -
407 a Abell Galaxy Cluster S 373 (AGC S 373) , 351–353 Achromat
Index A Barnard 72 , 210–211 Abell Galaxy Cluster S 373 (AGC S 373) , Barnard, E.E. , 5, 389 351–353 Barnard’s loop , 5–8 Achromat , 365 Barred-ring spiral galaxy , 235 Adaptive optics (AO) , 377, 378 Barred spiral galaxy , 146, 263, 295, 345, 354 AGC S 373. See Abell Galaxy Cluster Bean Nebulae , 303–305 S 373 (AGC S 373) Bernes 145 , 132, 138, 139 Alnitak , 11 Bernes 157 , 224–226 Alpha Centauri , 129, 151 Beta Centauri , 134, 156 Angular diameter , 364 Beta Chamaeleontis , 269, 275 Antares , 129, 169, 195, 230 Beta Crucis , 137 Anteater Nebula , 184, 222–226 Beta Orionis , 18 Antennae galaxies , 114–115 Bias frames , 393, 398 Antlia , 104, 108, 116 Binning , 391, 392, 398, 404 Apochromat , 365 Black Arrow Cluster , 73, 93, 94 Apus , 240, 248 Blue Straggler Cluster , 169, 170 Aquarius , 339, 342 Bok, B. , 151 Ara , 163, 169, 181, 230 Bok Globules , 98, 216, 269 Arcminutes (arcmins) , 288, 383, 384 Box Nebula , 132, 147, 149 Arcseconds (arcsecs) , 364, 370, 371, 397 Bug Nebula , 184, 190, 192 Arditti, D. , 382 Butterfl y Cluster , 184, 204–205 Arp 245 , 105–106 Bypass (VSNR) , 34, 38, 42–44 AstroArt , 396, 406 Autoguider , 370, 371, 376, 377, 388, 389, 396 Autoguiding , 370, 376–378, 380, 388, 389 C Caldwell Catalogue , 241 Calibration frames , 392–394, 396, B 398–399 B 257 , 198 Camera cool down , 386–387 Barnard 33 , 11–14 Campbell, C.T. , 151 Barnard 47 , 195–197 Canes Venatici , 357 Barnard 51 , 195–197 Canis Major , 4, 17, 21 S. Chadwick and I. Cooper, Imaging the Southern Sky: An Amateur Astronomer’s Guide, 407 Patrick Moore’s Practical -
Arxiv:Astro-Ph/0205130V1 9 May 2002 Bevtr,Wihi Prtdb H Soito Fuieste F Foundation
The Star Formation History and Mass Function of the Double Cluster h and Chi Persei Catherine L. Slesnick1, Lynne A. Hillenbrand1 Dept. of Astronomy, MS105-24, California Institute of Technology,Pasadena, CA 91125 [email protected], [email protected] and Philip Massey1 Lowell Observatory, 1400 W. Mars Hill Road, Flagstaff, AZ 86001 [email protected] ABSTRACT The h and χ Per “double cluster” is examined using wide-field (0.98◦ 0.98◦) × CCD UBV imaging supplemented by optical spectra of several hundred of the brightest stars. Restricting our analysis to near the cluster nuclei, we find iden- tical reddenings (E(B V )=0.56 0.01), distance moduli (11.85 0.05), and − ± ± ages (12.8 1.0 Myr) for the two clusters. In addition, we find an IMF slope for ± each of the cluster nuclei that is quite normal for high-mass stars,Γ= 1.3 0.2, − ± indistinguishable from a Salpeter value. We derive masses of 3700 ⊙ (h) and M 2800 ⊙ (χ) integrating the PDMF from 1 to 120 ⊙. There is evidence of arXiv:astro-ph/0205130v1 9 May 2002 M M mild mass segregation within the cluster cores. Our data are consistent with the stars having formed at a single epoch; claims to the contrary are very likely due to the inclusion of the substantial population of early-type stars located at sim- ilar distances in the Perseus spiral arm, in addition to contamination by G and K giants at various distances. We discuss the uniqueness of the double cluster, citing other examples of such structures in the literature, but concluding that the nearly identical nature of the two cluster cores is unusual. -
7.5 X 11.5.Threelines.P65
Cambridge University Press 978-0-521-19267-5 - Observing and Cataloguing Nebulae and Star Clusters: From Herschel to Dreyer’s New General Catalogue Wolfgang Steinicke Index More information Name index The dates of birth and death, if available, for all 545 people (astronomers, telescope makers etc.) listed here are given. The data are mainly taken from the standard work Biographischer Index der Astronomie (Dick, Brüggenthies 2005). Some information has been added by the author (this especially concerns living twentieth-century astronomers). Members of the families of Dreyer, Lord Rosse and other astronomers (as mentioned in the text) are not listed. For obituaries see the references; compare also the compilations presented by Newcomb–Engelmann (Kempf 1911), Mädler (1873), Bode (1813) and Rudolf Wolf (1890). Markings: bold = portrait; underline = short biography. Abbe, Cleveland (1838–1916), 222–23, As-Sufi, Abd-al-Rahman (903–986), 164, 183, 229, 256, 271, 295, 338–42, 466 15–16, 167, 441–42, 446, 449–50, 455, 344, 346, 348, 360, 364, 367, 369, 393, Abell, George Ogden (1927–1983), 47, 475, 516 395, 395, 396–404, 406, 410, 415, 248 Austin, Edward P. (1843–1906), 6, 82, 423–24, 436, 441, 446, 448, 450, 455, Abbott, Francis Preserved (1799–1883), 335, 337, 446, 450 458–59, 461–63, 470, 477, 481, 483, 517–19 Auwers, Georg Friedrich Julius Arthur v. 505–11, 513–14, 517, 520, 526, 533, Abney, William (1843–1920), 360 (1838–1915), 7, 10, 12, 14–15, 26–27, 540–42, 548–61 Adams, John Couch (1819–1892), 122, 47, 50–51, 61, 65, 68–69, 88, 92–93, -
LCSH Section H
H (The sound) H.P. 15 (Bomber) Giha (African people) [P235.5] USE Handley Page V/1500 (Bomber) Ikiha (African people) BT Consonants H.P. 42 (Transport plane) Kiha (African people) Phonetics USE Handley Page H.P. 42 (Transport plane) Waha (African people) H-2 locus H.P. 80 (Jet bomber) BT Ethnology—Tanzania UF H-2 system USE Victor (Jet bomber) Hāʾ (The Arabic letter) BT Immunogenetics H.P. 115 (Supersonic plane) BT Arabic alphabet H 2 regions (Astrophysics) USE Handley Page 115 (Supersonic plane) HA 132 Site (Niederzier, Germany) USE H II regions (Astrophysics) H.P.11 (Bomber) USE Hambach 132 Site (Niederzier, Germany) H-2 system USE Handley Page Type O (Bomber) HA 500 Site (Niederzier, Germany) USE H-2 locus H.P.12 (Bomber) USE Hambach 500 Site (Niederzier, Germany) H-8 (Computer) USE Handley Page Type O (Bomber) HA 512 Site (Niederzier, Germany) USE Heathkit H-8 (Computer) H.P.50 (Bomber) USE Hambach 512 Site (Niederzier, Germany) H-19 (Military transport helicopter) USE Handley Page Heyford (Bomber) HA 516 Site (Niederzier, Germany) USE Chickasaw (Military transport helicopter) H.P. Sutton House (McCook, Neb.) USE Hambach 516 Site (Niederzier, Germany) H-34 Choctaw (Military transport helicopter) USE Sutton House (McCook, Neb.) Ha-erh-pin chih Tʻung-chiang kung lu (China) USE Choctaw (Military transport helicopter) H.R. 10 plans USE Ha Tʻung kung lu (China) H-43 (Military transport helicopter) (Not Subd Geog) USE Keogh plans Ha family (Not Subd Geog) UF Huskie (Military transport helicopter) H.R.D. motorcycle Here are entered works on families with the Kaman H-43 Huskie (Military transport USE Vincent H.R.D.