DOCSLIB.ORG

A New Metal-Poor Globular Cluster and Resolved Stars in the Outer

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
A New Metal-Poor Globular Cluster and Resolved Stars in the Outer Draft version May 20, 2020 Typeset using LATEX preprint2 style in AASTeX63 A New Metal-poor Globular Cluster and Resolved Stars in the Outer Disk of the Black Eye Galaxy M64: Implication for the Origin of the Type III Disk Break Jisu Kang,1 Yoo Jung Kim,1 Myung Gyoon Lee,1 and In Sung Jang2 1Astronomy Program, Department of Physics and Astronomy, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea 2Leibniz-Institut f¨ur Astrophysik Potsdam (AIP), An der Sternwarte 16, 14482 Potsdam, Germany (Accepted May 18, 2020) Submitted to ApJ ABSTRACT M64 is a nearby spiral galaxy with a Type III anti-truncation component. To trace the origin of the Type III component, we present Hubble Space Telescope/Advanced Camera for Surveys F 606W/F 814W photometry of resolved stars in a field located in the outer disk (2.′5 . r . 6.′5) of M64. At r ≈ 5.′5 (7 kpc) to the east, we discover a new metal-poor globular cluster (Reff = 5.73 ± 0.02 pc and MV = −9.54 ± 0.09 mag), M64-GC1. This is the first globular cluster found in M64. The color-magnitude diagram (CMD) of the resolved stars in M64-GC1 is well matched by 12 Gyr isochrones with [Fe/H] = −1.5 ± 0.2, showing that this cluster belongs to a halo. The CMD of the resolved stars in the entire ACS field shows two distinguishable red giant branches (RGBs): a curved metal-rich RGB and a vertical metal- poor RGB. The metal-rich RGB represents an old metal-rich ([Fe/H] ≈ −0.4) disk population. In contrast, the CMD of the metal-poor RGB stars is very similar to the CMD of M64-GC1, showing that the metal-poor RGB represents a halo population. The radial number density profile of the metal-rich RGB stars is described by an exponential disk law, while the profile of the metal-poor RGB stars is described by a de Vaucouleurs’s law. From these, we conclude that the origin of the Type III component in M64 is a halo which has a much lower metallicity than a disk or bulge population. Keywords: galaxies: halos — galaxies: individual (M64) — galaxies: spiral — galaxies: arXiv:2005.09633v1 [astro-ph.GA] 19 May 2020 star clusters: individual (M64-GC1) — galaxies: stellar content 1. INTRODUCTION Galaxy due to its prominent dust lane around M64 (NGC 4826) is an early type spiral galaxy the bright bulge. The basic properties of M64 ((R)SA(rs)ab) with nicknames of Black Eye are listed in Table 1. Galaxy, Evil Eye Galaxy, and Sleeping Beauty M64 shows several interesting features. First, it is an isolated galaxy located in the low den- sity environment. It used to be known to Corresponding author: Myung Gyoon Lee [email protected],[email protected] have only one known companion dwarf galaxy, T NGC 4789A (MB ≈ −14 mag) (Jacobs et al. 2 Kang et al. Table 1. Basic Parameters of M64 HI distribution is much more extended (out to ≈ ′′ Parameter Value Ref. r 600 ) (Watkins et al. 2016). Another interesting feature of M64 is that R.A.(J2000) 12h 56m 43s.64 1 its disk is composed of three substructures. Decl.(J2000) +21◦ 40′ 58′′. 7 1 From the recent deep BV surface photome- Type (R)SA(rs)ab 2 try, Watkins et al. (2016) found that the sur- A A A B, V , I 0.150, 0.113, 0.062 3 face brightness profiles of M64 can be divided A A F 606W , F 814W 0.102, 0.063 3 into three parts: 1) an inner disk, 2) an outer E B V ( − ) 0.037 3 disk, and 3) a Type III anti-truncation (up- (m − M)0 28.18 ± 0.03(ran) ± 0.08(sys) 4 bending) component. In the inner disk region Distance 4.33 ± 0.18 Mpc 4 at r < 200′′, spiral arms and evidence of re- −1 Image scale 21.0 pc arcsec 4 cent star formation are seen. We can notice 1.26 kpc arcmin−1 4 dust lanes, young stars, strong UV emission, 75.6 kpc degree−1 4 and a high density of HI gas from the multi- BT , (B − V )T 9.36 ± 0.10, 0.84 ± 0.01 2 band images of M64 (see Watkins et al. 2016, T T B0 , (B − V )0 8.82 ± 0.10, 0.71 ± 0.01 2 Figure 3). The recent star formation in the M T M T . B , V −19 36 ± 0 13, −20 07 ± 0 13 2,4 inner disk is believed to be due to a merger Position angle 115 deg (B), 110 deg (Ks) 2 with a gas-rich dwarf galaxy (Braun et al. 1994; ′′ ′′ D25(B) 600. 00 × 324. 00 2 Watkins et al. 2016). In the outer disk region ′′ ′′ ′′ ′′ Dtot(Ks) 617. 60 × 352. 03 5 at 200 <r < 400 , no spiral arms or evi- −1 vhelio 408 ± 4 km s 2 dence of recent star formation are seen. Its color is red, indicating that the disk stars may be References—(1) NED (2) de Vaucouleurs et al. (1991) old and metal-rich (Watkins et al. 2016). Out- (3) Schlafly & Finkbeiner (2011) (4) This study (5) ′′ ′′ Jarrett et al. (2003) side of the outer disk at 400 <r< 900 , the Type III anti-truncation component is located. It is an upbending structure following a break at r ≈ 400′′ in the surface brightness profiles of 2009). Although several dwarf galaxies includ- M64. Its surface brightness is as low as µB > 27 T −2 ing Coma P (MB ≈ −10 mag) were recently mag arcsec . suggested to be another companions of M64 While the origins of the inner disk and the (Brunker et al. 2019; Carlsten et al. 2020), it outer disk are quite clear, the origin of the can be still considered as an isolated galaxy. Type III break is still mysterious. According Second, it hosts two counter-rotating gas rings: to Watkins et al. (2016), the origin of the Type the inner gas ring (r < 1′) follows the galaxy ro- III component in M64 can be explained by three tation, while the outer gas ring rotates in the op- scenarios. First, it can be originated from disk posite direction (Braun et al. 1992). The outer stars that migrated from the inner region. This ring is considered to be a remnant of a recent possibility is supported by the (B − V ) color of merger with a gas-rich satellite (Braun et al. the Type III component stars which is as red as 1992, 1994; Rubin 1994; Walterbos et al. 1994; that of the outer disk stars. However, the un- ′′ Rix et al. 1995; Watkins et al. 2016). Third, certainty of the color measurement for r > 400 recent star formation is concentrated only in is significant because of its low surface bright- the inner disk region at r < 200′′, while the ness. Moreover, it is difficult for disk stars to migrate such a large distance (several disk scale M64-GC1 and RGB stars 3 lengths beyond the spiral features). Second, the ′× ′ Type III component can be originated from star 12 12 SDSS color image of M64 formation in extended gas induced by counter rotating kinematics of M64. If so, the (B − V ) 44 color of the Type III component stars may be M64 much bluer (younger) than previously known. Third, it can be originated from halo stars. If Decl. so, the stars in this component must be old and 40 metal-poor. ′ Photometry of resolved stars located in the a = a25,B = 5 low surface brightness region of a galaxy is an HST/ACS excellent tool to study the nature of diffuse 21° 36′ 1′ galaxy light in terms of stellar populations and M64-GC1 to trace the origin of the stellar populations. In 12h 57m 00s 56m 40s 20s this study, we explore the origin of the Type III R.A. break using the photometry of resolved stars in an outer disk field of M64 based on the Hub- ′ × ′ ble Space Telescope (HST)/Advanced Camera Figure 1. The color map of the 12 12 SDSS image of M64. North is up and east to the left. for Surveys (ACS) images. To date, little is The image scale bar is shown on the bottom right. known about the resolved stars or star clus- ′ The large ellipse represents a25,B = 5.0 where a25,B ters in M64. We adopt the distance to M64, is the projected galactocentric distance at which 4.33 Mpc as determined later in this study. the B-band surface brightness is 25 mag arcsec−2. The foreground reddening toward M64 is as low The location of the HST/ACS field is marked in as E(B − V )= 0.037 (AF 606W = 0.102 and rectangles. The small circle on the HST/ACS field AF 814W =0.063) (Schlafly & Finkbeiner 2011). marks the new globular cluster (M64-GC1) found This paper is organized as follows. Section 2 in this study (see Figure 3). describes data used in this study and how we ′′ reduce and analyze the data. In Section 3, we s for F 814W . The final image scale is 0.05 per present main results: a discovery of a new glob- pixel. ular cluster, color-magnitude diagrams (CMDs) In Figure 1, the location of the HST/ACS of the resolved field stars, estimation of the tip field is marked on the SDSS color image of M64. ′ ′ of the red giant branch (TRGB) distance, and The ACS field is positioned at r = 2.3 to 6.2 ′ ′ radial number density profiles of the resolved (a = 2.4 to 6.6) along the eastern major axis stars.
Load more

Recommended publications
  • Central Coast Astronomy Virtual Star Party May 15Th 7Pm Pacific
    Central Coast Astronomy Virtual Star Party May 15th 7pm Pacific Welcome to our Virtual Star Gazing session! We’ll be focusing on objects you can see with binoculars or a small telescope, so after our session, you can simply walk outside, look up, and understand what you’re looking at. CCAS President Aurora Lipper and astronomer Kent Wallace will bring you a virtual “tour of the night sky” where you can discover, learn, and ask questions as we go along! All you need is an internet connection. You can use an iPad, laptop, computer or cell phone. When 7pm on Saturday night rolls around, click the link on our website to join our class. CentralCoastAstronomy.org/stargaze Before our session starts: Step 1: Download your free map of the night sky: SkyMaps.com They have it available for Northern and Southern hemispheres. Step 2: Print out this document and use it to take notes during our time on Saturday. This document highlights the objects we will focus on in our session together. Celestial Objects: Moon: The moon 4 days after new, which is excellent for star gazing! *Image credit: all astrophotography images are courtesy of NASA & ESO unless otherwise noted. All planetarium images are courtesy of Stellarium. Central Coast Astronomy CentralCoastAstronomy.org Page 1 Main Focus for the Session: 1. Canes Venatici (The Hunting Dogs) 2. Boötes (the Herdsman) 3. Coma Berenices (Hair of Berenice) 4. Virgo (the Virgin) Central Coast Astronomy CentralCoastAstronomy.org Page 2 Canes Venatici (the Hunting Dogs) Canes Venatici, The Hunting Dogs, a modern constellation created by Polish astronomer Johannes Hevelius in 1687.
    [Show full text]
  • RADIAL VELOCITIES in the ZODIACAL DUST CLOUD
    A SURVEY OF RADIAL VELOCITIES in the ZODIACAL DUST CLOUD Brian Harold May Astrophysics Group Department of Physics Imperial College London Thesis submitted for the Degree of Doctor of Philosophy to Imperial College of Science, Technology and Medicine London · 2007 · 2 Abstract This thesis documents the building of a pressure-scanned Fabry-Perot Spectrometer, equipped with a photomultiplier and pulse-counting electronics, and its deployment at the Observatorio del Teide at Izaña in Tenerife, at an altitude of 7,700 feet (2567 m), for the purpose of recording high-resolution spectra of the Zodiacal Light. The aim was to achieve the first systematic mapping of the MgI absorption line in the Night Sky, as a function of position in heliocentric coordinates, covering especially the plane of the ecliptic, for a wide variety of elongations from the Sun. More than 250 scans of both morning and evening Zodiacal Light were obtained, in two observing periods – September-October 1971, and April 1972. The scans, as expected, showed profiles modified by components variously Doppler-shifted with respect to the unshifted shape seen in daylight. Unexpectedly, MgI emission was also discovered. These observations covered for the first time a span of elongations from 25º East, through 180º (the Gegenschein), to 27º West, and recorded average shifts of up to six tenths of an angstrom, corresponding to a maximum radial velocity relative to the Earth of about 40 km/s. The set of spectra obtained is in this thesis compared with predictions made from a number of different models of a dust cloud, assuming various distributions of dust density as a function of position and particle size, and differing assumptions about their speed and direction.
    [Show full text]
  • The Mid-Infrared Extinction Law in the Ophiuchus, Perseus, and Serpens
    The Mid-Infrared Extinction Law in the Ophiuchus, Perseus, and Serpens Molecular Clouds Nicholas L. Chapman1,2, Lee G. Mundy1, Shih-Ping Lai3, Neal J. Evans II4 ABSTRACT We compute the mid-infrared extinction law from 3.6−24µm in three molecu- lar clouds: Ophiuchus, Perseus, and Serpens, by combining data from the “Cores to Disks” Spitzer Legacy Science program with deep JHKs imaging. Using a new technique, we are able to calculate the line-of-sight extinction law towards each background star in our fields. With these line-of-sight measurements, we create, for the first time, maps of the χ2 deviation of the data from two extinc- tion law models. Because our χ2 maps have the same spatial resolution as our extinction maps, we can directly observe the changing extinction law as a func- tion of the total column density. In the Spitzer IRAC bands, 3.6 − 8 µm, we see evidence for grain growth. Below AKs =0.5, our extinction law is well-fit by the Weingartner & Draine (2001) RV = 3.1 diffuse interstellar medium dust model. As the extinction increases, our law gradually flattens, and for AKs ≥ 1, the data are more consistent with the Weingartner & Draine RV = 5.5 model that uses larger maximum dust grain sizes. At 24 µm, our extinction law is 2 − 4× higher than the values predicted by theoretical dust models, but is more consistent with the observational results of Flaherty et al. (2007). Lastly, from our χ2 maps we identify a region in Perseus where the IRAC extinction law is anomalously high considering its column density.
    [Show full text]
  • GALAXIES WHAT ARE the DEEP SKY OBJECTS? •Deep-Sky Objects Are Astronomical Objects Other Than Individual Stars and Solar System Objects (Sun, Moon, Planets, Comets)
    GALAXIES WHAT ARE THE DEEP SKY OBJECTS? •Deep-sky objects are astronomical objects other than individual stars and solar system objects (Sun, Moon, planets, comets). TYPES OF DEEP SKY OBJECTS •Nebulae •Clusters •Galaxies CHARLES MESSIER • Known for the Messier catalogue of galaxies, nebulae and star clusters M1 to M110 • He was a French astronomer who lived in the 18th century. • He was a comet hunter and the purpose of the catalogue was to record the sky objects that looked as comets but were not comets because they would not move in the sky. UNITS TO MEASURE DISTANCE • A Light-year is the distance that light travels in a year with a speed of approximately 300,000 kilometers per second • Closest star to the Sun is Proxima Centauri at 4.37 light years. • A Parsec is the equal to about 3.26 light years GALAXIES • A galaxy is an enormous collection of gas, dust and billions of stars held together by gravity. One galaxy can have hundreds of billions of stars and be as large as 200,000 light years across. • Galaxy is derived from the Greek galaxias meaning "milky", a reference to the Milky Way. • Many galaxies are believed to have black holes at their active center. The Milky Way's central black hole, known as Sagittarius A, has a mass four million times that of our Sun. GALAXIES FACTS • There are potentially more than 170 billion galaxies in the observable universe. Some, called dwarf galaxies, are very small with about 10 million stars, while others are huge containing an estimated 100 trillion stars.
    [Show full text]
  • The Fornax 3D Project: Dust Mix and Gas Properties in the Center of Early-Type Galaxy FCC 167
    Astronomy & Astrophysics manuscript no. FCC167_accepted c ESO 2021 July 11, 2021 The Fornax 3D project: dust mix and gas properties in the center of early-type galaxy FCC 167 ? S. Viaene1; 2; , M. Sarzi3; 1, N. Zabel4, L. Coccato5, E. M. Corsini6; 7, T. A. Davis4, P. De Vis8, P. T. de Zeeuw9; 10, J. Falcón-Barroso11; 12, D.A. Gadotti5, E. Iodice13, M. Lyubenova5, R. McDermid14; 15, L. Morelli16; 6; 7, B. Nedelchev1, F. Pinna11; 12, T. W. Spriggs1, and G. van de Ven5 1 Centre for Astrophysics Research, University of Hertfordshire, College Lane, Hatfield AL10 9AB, UK 2 Sterrenkundig Observatorium, Universiteit Gent, Krijgslaan 281, B-9000 Gent, Belgium 3 Armagh Observatory and Planetarium, College Hill, Armagh, BT61 9DG, UK 4 School of Physics & Astronomy, Cardiff University, Queens Buildings, The Parade, Cardiff, CF24 3AA, UK 5 European Southern Observatory, Karl-Schwarzschild-Str. 2, 85748 Garching b. München, Germany 6 Dipartimento di Fisica e Astronomia ‘G. Galilei’, Università di Padova, vicolo dell’Osservatorio 3, I-35122 Padova, Italy 7 INAF–Osservatorio Astronomico di Padova, vicolo dell’Osservatorio 5, I-35122 Padova, Italy 8 Institut d’Astrophysique Spatiale, CNRS, Université Paris-Sud, Université Paris-Saclay, Bat. 121, F-91405 Orsay Cedex, France 9 Sterrewacht Leiden, Leiden University, Postbus 9513, 2300 RA Leiden, The Netherlands 10 Max-Planck-Institut fuer extraterrestrische Physik, Giessenbachstrasse, 85741 Garching bei Muenchen, Germany 11 Instituto de Astrofísica de Canarias, C/ Via Láctea s/n, E-38200 La Laguna, Tenerife,
    [Show full text]
  • Arxiv:1505.03150V2 [Astro-Ph.GA] 1 Jun 2015 Describe These Geometries
    Astronomy & Astrophysics manuscript no. NGC4370arXiv c ESO 2018 October 15, 2018 NGC4370: a case study for testing our ability to infer dust distribution and mass in nearby galaxies S. Viaene1, G. De Geyter1, M. Baes1, J. Fritz1; 2, G.J. Bendo3, M. Boquien4, A. Boselli5, S. Bianchi6, L. Cortese7, P. Côté8, J.-C. Cuillandre9, I. De Looze1; 10, S. di Serego Alighieri6, L. Ferrarese8, S. D. J. Gwyn11, T. M. Hughes1, and C. Pappalardo12 1 Sterrenkundig Observatorium, Universiteit Gent, Krijgslaan 281, B-9000 Gent, Belgium e-mail: [email protected] 2 Centro de Radioastronomía y Astrofísica, CRyA, UNAM, Campus Morelia, A.P. 3-72, C.P. 58089, Michoacán, Mexico 3 Jodrell Bank Centre for Astrophysics, School of Physics and Astronomy, University of Manchester, Oxford Road, Manchester M13 9PL, UK 4 Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge, CB3 0HA, UK 5 Laboratoire d’Astrophysique de Marseille, UMR 6110 CNRS, 38 rue F. Joliot-Curie, F-13388 Marseille, France 6 Osservatorio Astrofisico di Arcetri – INAF, Largo E. Fermi 5, 50125 Firenze, Italy 7 Centre for Astrophysics & Supercomputing, Swinburne University of Technology, Mail H30 – PO Box 218, Hawthorn, VIC 3122, Australia 8 National Research Council of Canada, Herzberg Astronomy and Astrophysics, 5071 W. Saanich Road, Victoria, BC V9E2E7, Canada 9 Canada-France-Hawaii Telescope, 65-1238 Mamalahoa Hwy, Kamuela, HI 96743 USA 10 Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge, CB3 0HA, UK 11 Canadian Astronomy Data Centre, 5071 West Saanich Rd, Victoria BC, V9E 2E7, Canada 12 Centro de Astronomia e Astrofísica da Universidade de Lisboa, Observatório Astronómico de Lisboa, Tapada da Ajuda, 1349-018 Lisbon, Portugal October 15, 2018 ABSTRACT Context.
    [Show full text]
  • Spiral Arm Structures Revealed in the M31 Galaxy Yu.N.Efremov
    1 Spiral arm structures revealed in the M31 galaxy Yu.N.Efremov Sternberg Astronomical Institute, MSU, Universitetsky pr. 13, Moscow, 11992 Russia Abstract Striking regularities are found in the northwestern arm of the M31 galaxy. Star complexes located in this arm are spaced 1.2 kpc apart and have similar sizes of about 0.6 kpc. This pattern is observed within the arm region where Beck et al. (1989) detected a strong regular magnetic field with the wavelength twice as large as the spacing between the complexes. Moreover, complexes are located mostly at the extremes of the wavy magnetic field. In this arm, groups of HII regions lie inside star complexes, which, in turn, are located inside the gas–dust lane. In contrast, the southwestern arm of М31 splits into a gas–dust lane upstream and a dense stellar arm downstream, with HII regions located mostly along the boundary between these components of the arm. The density of high-luminosity stars in the southwestern arm is much higher than in the northwestern arm, and the former is not fragmented into star complexes. Furthermore, signatures of the age gradient across the southwestern arm have been found in earlier observations. This drastic difference in the structure of the segments of the same arm (Baade’s arm S4) is probably due mostly to their different pitch angles: the pitch angle is of about 0 º for northwestern part of the arm and about 30 ° in the southwestern segment. According to the classical SDW theory, this might result in lower SFR in the former and in the triggering of high SFR in the latter.
    [Show full text]
  • Ritgerðin 2. Desember-ÞDH
    Stórbrotinn heimur hljóða Kvikmyndatónlist Amélie og Sherlock Holmes Karen Nadia Pálsdóttir Listaháskóli Íslands Tónlistardeild Söngur Stórbrotinn heimur hljóða Kvikmyndatónlist Amélie og Sherlock Holmes Karen Nadia Pálsdóttir Leiðbeinandi: Þorbjörg Daphne Hall Haustönn 2011 Í þessari ritgerð er fjallað um tónlist tveggja kvikmynda, Amélie eftir leikstjórann Jean-Pierre Jeunet og Sherlock Holmes í leikstjórn Guy Ritchie. Sérstaklega eru tónskáld umræddra mynda til umfjöllunar, sem og tónsköpun þeirra, og þau borin saman með áherslu á sameiginleg einkenni. Einnig er stuttlega fjallað um tónlist í kvikmyndum almennt, og stiklað á stóru um þróun kvikmyndatónlistar í Evrópu og Bandaríkjunum. Kvikmyndirnar Amélie og Sherlock Holmes eru ólíkar að mörgu leyti. Til að mynda er sú fyrrnefnda frönsk, framleidd með litlu fjármagni, á meðan sú síðarnefnda er stórmynd og framleidd í kvikmyndaborginni Hollywood. Ætla má að tónlistin í báðum myndum eigi stóran þátt í vinsældum þeirra, en tónskáld myndanna eru þeir Yann Tiersen, Amélie, og Hans Zimmer, Sherlock Holmes. Þeir eru mismunandi tónlistarmenn; Zimmer starfar sem kvikmyndatónskáld en Tiersen sem sjálfstæður tónlistarmaður, og gefur út plötur með eigin efni. Þrátt fyrir að hafa farið sitthvora leiðina sem tónlistarmenn hafa tónskáldin samskonar bakgrunn, úr rokktónlist. Áhrif frá þessum bakgrunni má túlka í tónlist þeirra, en hún á það sameiginlegt að vera oft á tíðum bæði drífandi og framsækin. Tónskáldin notuðu mismunandi aðferðir við tónsköpun fyrir myndirnar. Mikið af tónlist Amélie var af fyrri plötum Tiersens, og sú tónlist sem hann samdi fyrir myndina var ekki samin fyrir ákveðnar persónur né ákveðin atriði, á meðan Zimmer samdi alla tónlistina út frá myndinni sjálfri, með ákveðin atriði og persónur í huga.
    [Show full text]
  • Tidal Bridge and Tidal Dwarf Candidates in the Interacting System Arp194 3
    MNRAS 000, 1–11 (2016) Preprint 25 July 2021 Compiled using MNRAS LATEX style file v3.0 Tidal bridge and tidal dwarf candidates in the interacting system Arp194 Anatoly V. Zasov1,2⋆, Anna S. Saburova1, Oleg V. Egorov1, Viktor L. Afanasiev3 1 Sternberg Astronomical Institute, Moscow M.V. Lomonosov State University, Universitetskij pr., 13, Moscow, 119991, Russia 2 Faculty of Physics, Moscow M.V. Lomonosov State University, Leninskie gory 1, Moscow, 119991, Russia 3 Special Astrophysical Observatory, Russian Academy of Sciences, Nizhniy Arkhyz, Karachai-Cherkessian Republic 357147, Russia 25 July 2021 ABSTRACT Arp194 is a system of recently collided galaxies, where the southern galaxy (S) passed throughthe gaseousdisc of the northerngalaxy(N) which in turn consists of two close compo- nents. This system is of special interest due to the presence of regions of active star-formation in the bridge between galaxies, the brightest of which (the region A) has a size of at least 4 kpc. We obtained three spectral slices of the system for different slit positions at the 6-m tele- scope of SAO RAS. We estimated the radial distribution of line-of-sight velocity and velocity dispersion as well as the intensities of emission lines and oxygen abundance 12 + log(O/H). The gas in the bridge is only partially mixed chemically and spatially: we observe the O/H gradient with the galactocentric distances both from S and N galaxies and a high dispersion of O/H in the outskirts of N-galaxy. Velocity dispersion of the emission-line gas is the low- est in the star-forming sites of the bridge and exceeds 50-70 km/s in the disturbed region of N-galaxy.
    [Show full text]
  • NGC 4370: a Case Study for Testing Our Ability to Infer Dust Distribution and Mass in Nearby Galaxies
    A&A 579, A103 (2015) Astronomy DOI: 10.1051/0004-6361/201526147 & c ESO 2015 Astrophysics NGC 4370: a case study for testing our ability to infer dust distribution and mass in nearby galaxies S. Viaene1, G. De Geyter1, M. Baes1, J. Fritz1;2, G. J. Bendo3, M. Boquien4, A. Boselli5, S. Bianchi6, L. Cortese7, P. Côté8, J.-C. Cuillandre9, I. De Looze1;10, S. di Serego Alighieri6, L. Ferrarese8, S. D. J. Gwyn11, T. M. Hughes1, and C. Pappalardo12 1 Sterrenkundig Observatorium, Universiteit Gent, Krijgslaan 281, 9000 Gent, Belgium e-mail: [email protected] 2 Centro de Radioastronomía y Astrofísica, CRyA, UNAM, Campus Morelia, A.P. 3-72, CP 58089, Michoacán, Mexico 3 Jodrell Bank Centre for Astrophysics, School of Physics and Astronomy, University of Manchester, Oxford Road, Manchester M13 9PL, UK 4 Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge, CB3 0HA, UK 5 Laboratoire d’Astrophysique de Marseille, UMR 6110 CNRS, 38 rue F. Joliot-Curie, 13388 Marseille, France 6 Osservatorio Astrofisico di Arcetri – INAF, Largo E. Fermi 5, 50125 Firenze, Italy 7 Centre for Astrophysics & Supercomputing, Swinburne University of Technology, Mail H30 – PO Box 218, VIC 3122 Hawthorn, Australia 8 National Research Council of Canada, Herzberg Astronomy and Astrophysics, 5071 W. Saanich Road, Victoria, BC V9E2E7, Canada 9 Canada-France-Hawaii Telescope, 65-1238 Mamalahoa Hwy, Kamuela, HI 96743, USA 10 Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge, CB3 0HA, UK 11 Canadian Astronomy Data Centre, 5071 West Saanich Rd, Victoria BC, V9E 2E7, Canada 12 Centro de Astronomia e Astrofísica da Universidade de Lisboa, Observatório Astronómico de Lisboa, Tapada da Ajuda, 1349-018 Lisbon, Portugal Received 20 March 2015 / Accepted 7 May 2015 ABSTRACT Context.
    [Show full text]
  • YANN TIERSEN Ore 21,30 - Ingresso 30 Euro
    MONFORTINJAZZ 2011 Auditorium Horszowski di Monforte d'Alba (Cn) venerdì 8 luglio YANN TIERSEN ore 21,30 - ingresso 30 euro Un grande esordio per Monfortinjazz: venerdì 8 luglio primo appuntamento del breve tour italiano di Yann Tiersen, uno dei musicisti più importanti cresciuti durante la "neo nouvelle vague" francese esplosa verso la metà degli anni '90. Tra produttori house e techno e nuovi cantautori, Tiersen apparve come un nuovo compositore fuori dal tempo. Per metà belga e per metà norvegese, ma parigino d’adozione è certamente noto ai più per aver composto la colonna sonora del successo cinematografico Il favoloso mondo di Amélie, una serie di ballate fuori dal tempo capaci di trasmettere universalmente la semplice bellezza della sua musica. Tiersen, lungi dal restare intrappolato nel cliché di quelle composizioni, ha riscoperto al contempo la sua formazione classica e le esperienze in ambito più propriamente rock. Il recente Dust Lane è il sesto disco della serie e segue di ben cinque anni l'ottimo Les Retrouvailles che aveva conseguito un credibile equilibrio tra raffinata chanson e atmosfere incantate. Il Dust Lane Tour è un’apoteosi di riff di chitarra accanto a violini, mandolini, oscillatori, moog. Uno spettacolo in cui strumenti acustici, elettrici ed elettronici si fondono insieme per creare sonorità affascinanti, dove, l'idea statica di genere musicale cede il passo ad un grandioso talento compositivo e una forte presenza scenica. Yann Tiersen è nato a Brest e vive a Parigi. Da ragazzo ha studiato musica classica presso alcune accademie musicali francesi (Rennes, Nantes, Boulogne e altre), e più tardi ha fatto parte di alcune rock band.
    [Show full text]
  • Atomic and Molecular Gas in the Merger Galaxy NGC 1316
    Astronomy & Astrophysics manuscript no. (will be inserted by hand later) Atomic and molecular gas in the merger galaxy NGC 1316 (Fornax A) and its environment C. Horellou1, J.H. Black1, J.H. van Gorkom2, F. Combes3, J.M. van der Hulst4, and V. Charmandaris5 1 Onsala Space Observatory, Centre for Astrophysics & Space Science, Chalmers University of Technology, S– 439 92 Onsala, Sweden e-mail: [email protected], [email protected] 2 Astronomy Department, Columbia University, 538 W 120 Street, New York, NY 10027, USA e-mail: [email protected] 3 Observatoire de Paris, DEMIRM, 61 avenue de l’Observatoire, F-75014 Paris, France e-mail: [email protected] 4 Kapteyn Institute, Department of Astronomy, Postbus 800, 9700 AV Groningen, The Netherlands e-mail: [email protected] 5 Cornell University, Astronomy Department, 106 Space Sciences Building, Ithaca, NY 14853, USA e-mail: [email protected] Received 4 May 2001/ Accepted 18 July 2001 Abstract. We present and interpret observations of atomic and molecular gas toward the southern elliptical galaxy NGC 1316 (Fornax A), a strong double-lobe radio source with a disturbed optical morphology that includes numerous shells and loops. The 12CO(1–0), 12CO(2–1), and Hi observations were made with SEST and the VLA. 8 CO emission corresponding to a total molecular hydrogen mass of ∼5×10 M⊙ was detected toward the central position as well as northwest and southeast of the nucleus in the regions of the dust patches. The origin of that gas is likely external and due to accretion of one or several small gas-rich galaxies.
    [Show full text]