Luminous Blue Variables
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The HERACLES View of the H -To-HI Ratio in Galaxies
The HERACLES View of the H2-to-HI Ratio in Galaxies Adam Leroy (NRAO, Hubble Fellow) Fabian Walter, Frank Bigiel, the HERACLES and THINGS teams The Saturday Morning Summary • Star formation rate vs. gas relation on ~kpc scales breaks apart into: A relatively universal CO-SFR relation in nearby disks Systematic environmental scalings in the CO-to-HI ratio • The CO-to-HI ratio is a strong function of radius, total gas, and stellar surface density correlated with ISM properties: dust-to-gas ratio, pressure harder to link to dynamics: gravitational instability, arms • Interpretation: the CO-to-HI ratio traces the efficiency of GMC formation Density and dust can explain much of the observed behavior heracles Fabian Walter Erik Rosolowsky MPIA UBC Frank Bigiel Eva Schinnerer UC Berkeley THINGS plus… MPIA Elias Brinks Antonio Usero Gaelle Dumas U Hertfordshire OAN, Madrid MPIA Erwin de Blok Andreas Schruba Helmut Wiesemeyer U Cape Town IRAM … MPIA Rob Kennicutt Axel Weiss Karl Schuster Cambridge MPIfR IRAM Barry Madore Carsten Kramer Karin Sandstrom Carnegie IRAM MPIA Michele Thornley Daniela Calzetti Kelly Foyle Bucknell UMass MPIA Collaborators The HERA CO-Line Extragalactic Survey First maps Leroy et al. (2009) • IRAM 30m Large Program to map CO J = 2→1 line • Instrument: HERA receiver array operating at 230 GHz • 47 galaxies: dwarfs to starbursts and massive spirals -2 • Very wide-field (~ r25) and sensitive (σ ~ 1-2 Msun pc ) NGS The HI Nearby Galaxy Survey HI Walter et al. (2008), AJ Special Issue (2008) • VLA HI maps of 34 galaxies: -
Big Halpha Kinematical Sample of Barred Spiral Galaxies - I
BhaBAR: Big Halpha kinematical sample of BARred spiral galaxies - I. Fabry-Perot Observations of 21 galaxies O. Hernandez, C. Carignan, P. Amram, L. Chemin, O. Daigle To cite this version: O. Hernandez, C. Carignan, P. Amram, L. Chemin, O. Daigle. BhaBAR: Big Halpha kinematical sample of BARred spiral galaxies - I. Fabry-Perot Observations of 21 galaxies. Monthly Notices of the Royal Astronomical Society, Oxford University Press (OUP): Policy P - Oxford Open Option A, 2005, 360 Issue 4, pp.1201. 10.1111/j.1365-2966.2005.09125.x. hal-00014446 HAL Id: hal-00014446 https://hal.archives-ouvertes.fr/hal-00014446 Submitted on 26 Jan 2021 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Mon. Not. R. Astron. Soc. 360, 1201–1230 (2005) doi:10.1111/j.1365-2966.2005.09125.x BHαBAR: big Hα kinematical sample of barred spiral galaxies – I. Fabry–Perot observations of 21 galaxies O. Hernandez,1,2 † C. Carignan,1 P. Amram,2 L. Chemin1 and O. Daigle1 1Observatoire du mont Megantic,´ LAE, Universitede´ Montreal,´ CP 6128 succ. centre ville, Montreal,´ Quebec,´ Canada H3C 3J7 2Observatoire Astronomique de Marseille Provence et LAM, 2 pl. -
Hubble Space Telescope Observer’S Guide Winter 2021
HUBBLE SPACE TELESCOPE OBSERVER’S GUIDE WINTER 2021 In 2021, the Hubble Space Telescope will celebrate 31 years in operation as a powerful observatory probing the astrophysics of the cosmos from Solar system studies to the high-redshift universe. The high-resolution imaging capability of HST spanning the IR, optical, and UV, coupled with spectroscopic capability will remain invaluable through the middle of the upcoming decade. HST coupled with JWST will enable new innovative science and be will be key for multi-messenger investigations. Key Science Threads • Properties of the huge variety of exo-planetary systems: compositions and inventories, compositions and characteristics of their planets • Probing the stellar and galactic evolution across the universe: pushing closer to the beginning of galaxy formation and preparing for coordinated JWST observations • Exploring clues as to the nature of dark energy ACS SBC absolute re-calibration (Cycle 27) reveals 30% greater • Probing the effect of dark matter on the evolution sensitivity than previously understood. More information at of galaxies http://www.stsci.edu/contents/news/acs-stans/acs-stan- • Quantifying the types and astrophysics of black holes october-2019 of over 7 orders of magnitude in size WFC3 offers high resolution imaging in many bands ranging from • Tracing the distribution of chemicals of life in 2000 to 17000 Angstroms, as well as spectroscopic capability in the universe the near ultraviolet and infrared. Many different modes are available for high precision photometry, astrometry, spectroscopy, mapping • Investigating phenomena and possible sites for and more. robotic and human exploration within our Solar System COS COS2025 initiative retains full science capability of COS/FUV out to 2025 (http://www.stsci.edu/hst/cos/cos2025). -
The ARAUCARIA Project – First Observations of Blue Supergiants in NGC 3109
Reports from Observers The ARAUCARIA Project – First Observations of Blue Supergiants in NGC 3109 Chris Evans1 Fabio Bresolin Miguel Urbaneja Grzegorz Pietrzyn´ski 3,4 Wolfgang Gieren 3 Rolf-Peter Kudritzki 1 United Kingdom Astronomy Technology Centre, Edinburgh, United Kingdom Institute for Astronomy, University of Hawaii, USA 3 Universidad de Concepción, Chile 4 Warsaw University Observatory, Poland NGC 3109 is an irregular galaxy at the edge of the Local Group at a distance of 1.3 Mpc. Here we present new VLT observations of its young, massive star population, which have allowed us to probe stellar abundances and kinemat- ics for the first time. The mean oxygen abundance obtained from early B-type supergiants confirms suggestions that NGC 3109 is a large Magellanic Irregular Figure 1: Part of the V-band FORS pre-image of our NGC 3109 is very metal poor. In this at 1.3 Mpc, which puts it at the outer edge most western field, with the targets encircled. NGC 3109 is approximately edge-on and the FORS context we advocate studies of the stel- of the Local Group. Using FORS in the targets are well sampled along both the major lar population of NGC 3109 as a com- configurable MOS (multi-object spectros- and minor axes. pelling target for future Extremely Large copy) mode, we have observed 91 stars Telescopes (ELTs). in NGC 3109. These were observed in Example spectra are shown in Figure . 4 MOS configurations, using the 600 B Of our 91 targets, 1 are late O-type stars, grism (giving a common wavelength cov- ranging from O8 to O9.5 – such high- The ARAUCARIA Project is an ESO Large erage of l3900 to l4750 Å). -
SCI/TSPM-PDR/001 Issue: 1.B Date: 20/10/2017 Pages
TSPM Science Document Code: SCI/TSPM-PDR/001 Issue: 1.B Date: 20/10/2017 Pages: 86 Code: SCI/TSPM-PDR/001 TSPM Science Document Issue: 1.B Date: 20/10/2017 Page: 2 of 86 Fernando Fabián Rosales Ortega (Project Scientist) Authors: Jesús González William Lee Revised by: Approved by: Contributors Galactic and stellar astronomy Extragalactic astronomy & Cosmology Carmen Ayala Heinz Andernach Emmanuele Bertone César A. Caretta Mónica W. Blanco Cárdenas Alberto Carramiñana Miguel Chávez Dagostino Marcel Chow-Martínez Luis J. Corral Deborah Dultzin Kessler Arturo Gómez-Ruíz Héctor Javier Ibarra Medel Martin A. Guerrero Simon N. Kemp Silvana G. Navarro Jiménez Omar López Cruz Manuel Nuñez Divakara Mayya Lorenzo Olguín Daniel Rosa Gonzalez Gerardo Ramos Larios Juan Pablo Torres Papaqui Mauricio Reyes Ruíz Olga Vega Michael Richer Carlos Román Zúñiga Future instrumentation Laurence Sabin Edgar Castillo Domínguez Miguel Ángel Trinidad Perla Carolina García Flores Roberto Vázquez Meza Sebastián F. Sánchez Sánchez Juan Luis Verbena Contreras Laurence Sabin Code: SCI/TSPM-PDR/001 TSPM Science Document Issue: 1.B Date: 20/10/2017 Page: 3 of 86 Distribution List Name Affiliation TSPM team All partners Document Change Record Issue Date Section Page Change description 1.A 17/09/2016 All All First issue Document updated from previous version. New science cases and instrumentation proposals included. 1.B 20/10/2017 Comments from the previous PDR panel considered. Comments and contributions from the TSPM Core Science Group included. Applicable and Reference Documents Nº Document Name Code R.1 TSPM: List of acronyms and abbreviations TEC/TSPM/001 Code: SCI/TSPM-PDR/001 TSPM Science Document Issue: 1.B Date: 20/10/2017 Page: 4 of 86 INDEX 1. -
Luminous Blue Variables
Review Luminous Blue Variables Kerstin Weis 1* and Dominik J. Bomans 1,2,3 1 Astronomical Institute, Faculty for Physics and Astronomy, Ruhr University Bochum, 44801 Bochum, Germany 2 Department Plasmas with Complex Interactions, Ruhr University Bochum, 44801 Bochum, Germany 3 Ruhr Astroparticle and Plasma Physics (RAPP) Center, 44801 Bochum, Germany Received: 29 October 2019; Accepted: 18 February 2020; Published: 29 February 2020 Abstract: Luminous Blue Variables are massive evolved stars, here we introduce this outstanding class of objects. Described are the specific characteristics, the evolutionary state and what they are connected to other phases and types of massive stars. Our current knowledge of LBVs is limited by the fact that in comparison to other stellar classes and phases only a few “true” LBVs are known. This results from the lack of a unique, fast and always reliable identification scheme for LBVs. It literally takes time to get a true classification of a LBV. In addition the short duration of the LBV phase makes it even harder to catch and identify a star as LBV. We summarize here what is known so far, give an overview of the LBV population and the list of LBV host galaxies. LBV are clearly an important and still not fully understood phase in the live of (very) massive stars, especially due to the large and time variable mass loss during the LBV phase. We like to emphasize again the problem how to clearly identify LBV and that there are more than just one type of LBVs: The giant eruption LBVs or h Car analogs and the S Dor cycle LBVs. -
Annual Report 2016–2017 AAVSO
AAVSO The American Association of Variable Star Observers Annual Report 2016–2017 AAVSO Annual Report 2012 –2013 The American Association of Variable Star Observers AAVSO Annual Report 2016–2017 The American Association of Variable Star Observers 49 Bay State Road Cambridge, MA 02138-1203 USA Telephone: 617-354-0484 Fax: 617-354-0665 email: [email protected] website: https://www.aavso.org Annual Report Website: https://www.aavso.org/annual-report On the cover... At the 2017 AAVSO Annual Meeting.(clockwise from upper left) Knicole Colon, Koji Mukai, Dennis Conti, Kristine Larsen, Joey Rodriguez; Rachid El Hamri, Andy Block, Jane Glanzer, Erin Aadland, Jamin Welch, Stella Kafka; and (clockwise from upper left) Joey Rodriguez, Knicole Colon, Koji Mukai, Frans-Josef “Josch” Hambsch, Chandler Barnes. Picture credits In additon to images from the AAVSO and its archives, the editors gratefully acknowledge the following for their image contributions: Glenn Chaple, Shawn Dvorak, Mary Glennon, Bill Goff, Barbara Harris, Mario Motta, NASA, Gary Poyner, Msgr. Ronald Royer, the Mary Lea Shane Archives of the Lick Observatory, Chris Stephan, and Wheatley, et al. 2003, MNRAS, 345, 49. Table of Contents 1. About the AAVSO Vision and Mission Statement 1 About the AAVSO 1 What We Do 2 What Are Variable Stars? 3 Why Observe Variable Stars? 3 The AAVSO International Database 4 Observing Variable Stars 6 Services to Astronomy 7 Education and Outreach 9 2. The Year in Review Introduction 11 The 106th AAVSO Spring Membership Meeting, Ontario, California 11 The -
The Saga of M81: Global View of a Massive Stellar Halo in Formation
Draft version October 27, 2020 Typeset using LATEX twocolumn style in AASTeX63 The Saga of M81: Global View of a Massive Stellar Halo in Formation Adam Smercina ,1, 2 Eric F. Bell ,1 Paul A. Price,3 Colin T. Slater ,2 Richard D'Souza,1, 4 Jeremy Bailin ,5 Roelof S. de Jong ,6 In Sung Jang ,6 Antonela Monachesi ,7, 8 and David Nidever 9, 10 1Department of Astronomy, University of Michigan, Ann Arbor, MI 48109, USA 2Astronomy Department, University of Washington, Box 351580, Seattle, WA 98195-1580, USA 3Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544, USA 4Vatican Observatory, Specola Vaticana, V-00120, Vatican City State 5Department of Physics and Astronomy, University of Alabama, Box 870324, Tuscaloosa, AL 35487-0324, USA 6Leibniz-Institut f¨urAstrophysik Potsdam (AIP), An der Sternwarte 16, 14482 Potsdam, Germany 7Instituto de Investigaci´onMultidisciplinar en Ciencia y Tecnolog´ıa,Universidad de La Serena, Ra´ulBitr´an1305, La Serena, Chile 8Departamento de F´ısica y Astronom´ıa,Universidad de La Serena, Av. Juan Cisternas 1200 N, La Serena, Chile 9Department of Physics, Montana State University, P.O. Box 173840, Bozeman, MT 59717-3840 10National Optical Astronomy Observatory, 950 North Cherry Ave, Tucson, AZ 85719 (Received 31 October, 2019; Revised 31 August, 2020; Accepted 23 October, 2020) Submitted to The Astrophysical Journal ABSTRACT Recent work has shown that Milky Way-mass galaxies display an incredible range of stellar halo properties, yet the origin of this diversity is unclear. The nearby galaxy M81 | currently interacting with M82 and NGC 3077 | sheds unique light on this problem. -
NEUTRAL HYDROGEN CLOUDS in the M81/M82 GROUP KM Chynoweth
University of Massachusetts Amherst ScholarWorks@UMass Amherst Astronomy Department Faculty Publication Series Astronomy 2008 NEUTRAL HYDROGEN CLOUDS IN THE M81/M82 GROUP KM Chynoweth GI Langston Min Yun University of Massachusetts - Amherst FJ Lockman KHR Rubin See next page for additional authors Follow this and additional works at: https://scholarworks.umass.edu/astro_faculty_pubs Part of the Astrophysics and Astronomy Commons Recommended Citation Chynoweth, KM; Langston, GI; Yun, Min; Lockman, FJ; Rubin, KHR; and Scoles, SA, "NEUTRAL HYDROGEN CLOUDS IN THE M81/M82 GROUP" (2008). The Astrophysical Journal. 1129. 10.1088/0004-6256/135/6/1983 This Article is brought to you for free and open access by the Astronomy at ScholarWorks@UMass Amherst. It has been accepted for inclusion in Astronomy Department Faculty Publication Series by an authorized administrator of ScholarWorks@UMass Amherst. For more information, please contact [email protected]. Authors KM Chynoweth, GI Langston, Min Yun, FJ Lockman, KHR Rubin, and SA Scoles This article is available at ScholarWorks@UMass Amherst: https://scholarworks.umass.edu/astro_faculty_pubs/1129 Neutral Hydrogen Clouds in the M81/M82 Group Katie M. Chynoweth1 Vanderbilt University, Physics and Astronomy Department, 1807 Station B, Nashville, TN 37235 Glen I. Langston National Radio Astronomy Observatory, Green Bank, WV 24944 Min S. Yun University of Massachusetts, 710 North Pleasant Street, Amherst, MA 01002 Felix J. Lockman, K.H.R. Rubin2 and Sarah A. Scoles3 National Radio Astronomy Observatory, Green Bank, WV 24944 ABSTRACT We have observed a 3◦ ×3◦ area centered on the M81/M82 group of galaxies using the Robert C. Byrd Green Bank Telescope (GBT) in a search for analogs to the High Velocity Clouds (HVCs) of neutral hydrogen found around our galaxy. -
Astronomy Magazine Special Issue
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OBSERVERS with the VLT VLT/ISAAC and HST/WFPC2 Observations of NGC 3603
OBSERVERS WITH THE VLT VLT/ISAAC and HST/WFPC2 Observations of NGC 3603 B. BRANDL1, W. BRANDNER2, E.K. GREBEL3 AND H. ZINNECKER 4* 1Cornell University, Ithaca; 2University of Hawaii, Honolulu; 3University of Washington at Seattle; 4Astrophysikalisches Institut Potsdam 1. Abstract spectral signatures of Wolf-Rayet (W-R) side (Churchwell et al. 1987; O’Dell et al. stars contribute more than 2000 M0 to 1993). FUV photons (13.6 eV > hν > 6 We have studied NGC 3603, the the cluster mass. Normally, W-R stars are eV) heat up the inside of the proplyd en- most massive visible HII region in the evolved supergiants that have long left velope and lead to the dissociation of mol- Galaxy, with VLT/ISAAC in the near-in- the main sequence and have ages of 3–5 ecules in the outer layers of the circum- frared (NIR) Js, H, and Ks-bands and Myr. In NGC 3603, however, the W-R stellar disk (Johnstone et al. 1998). The HST/WFPC2 at Hα and [N II] wave- stars also show hydrogen absorption resulting evaporation flow provides a lengths. In this Messenger article we lines in addition to the typical W-R fea- steady supply of neutral atoms to the ion- describe the data analysis and some tures. It is believed that these stars are isation front and leads to the development first results from both our complemen- still main-sequence, core hydrogen- of a cometary tail (McCullough et al. 1995; tary observations. burning stars that are so massive and so Störzer & Hollenbach 1999). Until re- Our HST/WFPC2 gave us an un- close to the Eddington limit that they are cently, only one other proplyd had been precedented high-resolution view of loosing their outer envelopes through fast found outside the Orion nebula. -
A Blast Wave from the 1843 Eruption of Eta Carinae
1 A Blast Wave from the 1843 Eruption of Eta Carinae Nathan Smith* *Astronomy Department, University of California, 601 Campbell Hall, Berkeley, CA 94720-3411 Very massive stars shed much of their mass in violent precursor eruptions [1] as luminous blue variables (LBVs) [2] before reaching their most likely end as supernovae, but the cause of LBV eruptions is unknown. The 19th century eruption of Eta Carinae, the prototype of these events [3], ejected about 12 solar masses at speeds of 650 km/s, with a kinetic energy of almost 1050ergs[4]. Some faster material with speeds up to 1000-2000 km/s had previously been reported [5,6,7,8] but its full distribution was unknown. Here I report observations of much faster material with speeds up to 3500-6000 km/s, reaching farther from the star than the fastest material in earlier reports [5]. This fast material roughly doubles the kinetic energy of the 19th century event, and suggests that it released a blast wave now propagating ahead of the massive ejecta. Thus, Eta Carinae’s outer shell now mimics a low-energy supernova remnant. The eruption has usually been discussed in terms of an extreme wind driven by the star’s luminosity [2,3,9,10], but fast material reported here suggests that it was powered by a deep-seated explosion rivalling a supernova, perhaps triggered by the pulsational pair instability[11]. This may alter interpretations of similar events seen in other galaxies. Eta Carinae [3] is the most luminous and the best studied among LBVs [1,2].