STAR CLUSTERS Lecture 1 Introduction Nora Lützgendorf (ESA)
Its a school, so????????? ASK QUESTIONS!!! If you don t understand the content If you don t understand the language TAKE NOTES This is the most text on a slide you will see ;) Nora Lützgendorf, KAS16 2 / 49
Outline 1. Career 2. Introduction a. What is a star cluster? b. What kind of clusters do we know? c. Where do we find them? d. Characteristics Nora Lützgendorf, KAS16 3 / 49
Outline 1. Career 2. Introduction a. What is a star cluster? b. What kind of clusters do we know? c. Where do we find them? d. Characteristics Nora Lützgendorf, KAS16 4 / 49
Current Position JWST/NIRSpec Instrument and Calibration Scientist Nora Lützgendorf, KAS16 5 / 49
European Space Agency space science human spaceflight exploration launchers operations navigation earth observation telecommunications technology Nora Lützgendorf, KAS16 6 / 49
James Webb Space Telescope FACTS WHAT: Infrared space telescope WHERE: Lagrange Point 2 WHEN: October 2018 MIRROR: 6.5 m Nora Lützgendorf, KAS16 7 / 49
James Webb Space Telescope Nora Lützgendorf, KAS16 8 / 49
James Webb Space Telescope Nora Lützgendorf, KAS16 8 / 49
Current Position LAUNCH SEGMENT OBSERVATORY SEGMENT GROUND SEGMENT Payload adapter Launcher (Ariane 5) Launch site services Spacecraft (bus, sunshield ) Telescope Payload module (ISIM) and instruments Science and operation center (STScI) NIRCam NIRSpec 15 ESA staff members FGS/NIRISS MIRI Common systems (deep space network) Provided by NASA Provided by ESA Provided by CSA Nora Lützgendorf, KAS16 9 / 49
NIRSpec Fixed Slit Spectroscopy Multi Object Spectroscopy Integral Field Spectroscopy Nora Lützgendorf, KAS16 10 / 49
Tasks BEFORE LAUNCH (2018) 80% duties, 20% science assist in calibration campaigns (like Cryo Vacuum Tests at NASA) reduce and analyze data from these campaigns create calibration files for the instruments (flatfields, darks, ) assist in GTO observation preparations AFTER LAUNCH 50% duties, 50% science commissioning (final calibration and science verification of the instrument) user support (help astronomers to observe with the instrument) calibration monitoring (degrading of hardware, change in instrument ) Making sure the instrument is usable for doing Astronomy Making sure astronomers use the instrument most efficiently Nora Lützgendorf, KAS16 11 / 49
How did I get here? LEIDEN, NL (2013-2015) 2013 2015: Research Fellow, ESA LEIPZIG, D (1985-2004) 1996 2004: High-School BALTIMORE, US (since 2015) MUNICH, D (2005-2013) 2005-2010: Diplom (Physics), LMU 2010-2013: PhD (Astrophysics), LMU/ESO since 2015: JWST Instrument Scientist, ESA Nora Lützgendorf, KAS16 12 / 49
Outline 1. Career 2. Introduction a. What is a star cluster? b. What kind of clusters do we know? c. Where do we find them? d. Characteristics Nora Lützgendorf, KAS16 13 / 49
Introduction The Milky Way is nothing else but a mass of innumerable stars planted together in clusters - Galileo Galilei (1610) Nora Lützgendorf, KAS16 14 / 49
Introduction Most stars form in clusters - Lada & Lada (2003) Nora Lützgendorf, KAS16 15 / 49
Star Cluster Collection of stars roughly born at the same time Collection of stars that are gravitationally bound Nora Lützgendorf, KAS16 16 / 49
Excursion: Color-magnitude diagram L/M V HOT T/(V-I) COLD Nora Lützgendorf, KAS16 17 / 49
Color-magnitude diagram Nora Lützgendorf, KAS16 18 / 49
Excursion: Color-magnitude diagram He He H+He 3) Horizontal Branch Star H+He 2) Red Giant L/M V C+O He H+He 4) Asymptotic Giant H+He 1) Main Sequence Star C+O 5) White Dwarf HOT T/(V-I) COLD Nora Lützgendorf, KAS16 19 / 49
Excursion: Color-magnitude diagram Marcia Rieke Nora Lützgendorf, KAS16 20 / 49
Excursion: Color-magnitude diagram Marcia Rieke Nora Lützgendorf, KAS16 20 / 49
Excursion: Color-magnitude diagram Marcia Rieke Nora Lützgendorf, KAS16 20 / 49
Excursion: Color-magnitude diagram Marcia Rieke Nora Lützgendorf, KAS16 20 / 49
Excursion: Color-magnitude diagram Marcia Rieke Nora Lützgendorf, KAS16 20 / 49
Types of clusters N stars 100-1000 1e4-1e6 1e4-1e5 1e5-1e7 1e6-1e8 OB Associations Embedded Open Globular Nuclear Nora Lützgendorf, KAS16 21 / 49
Environment Open Nuclear OB Associations Embedded Globular Nora Lützgendorf, KAS16 22 / 49
Types of clusters N stars 100-1000 1e4-1e6 1e4-1e5 1e5-1e7 1e6-1e8 OB Association Embedded Open Globular Nuclear Nora Lützgendorf, KAS16 23 / 49
- 20-500 pc - 0.1 stars/pc - gravitationally unbound - 12 within 650 pc OB Associations 300 pc SMC - NGC 346 M33 - NGC 604 70 pc Nora Lützgendorf, KAS16 24 / 49
Star Cluster Collection of stars roughly born at the same time Collection of stars that are gravitationally bound Nora Lützgendorf, KAS16 25 / 49
Types of clusters N stars 100-1000 1e4-1e6 1e4-1e5 1e5-1e7 1e6-1e8 OB Associations Embedded Open Globular Nuclear Nora Lützgendorf, KAS16 26 / 49
Embedded clusters - 1-10 pc - 100-1000 stars/pc 3 - age < 5 Myr - may or may not be bound - still gas in / around the cluster High extinction 4 3 2 J-H 1 0 1 1 0 1 2 3 4 H-K Nora Lützgendorf, KAS16 27 / 49
Embedded clusters Nora Lützgendorf, KAS16 28 / 43 49
Types of clusters N stars 100-1000 1e4-1e6 1e4-1e5 1e5-1e7 1e6-1e8 OB Associations Embedded Open Globular Nuclear Nora Lützgendorf, KAS16 29 / 49
Open clusters - core radii ~ 2pc - mass ~ 100-1000 MSUN - age: between 3 Myr and a few Gyr - no gas left - gravitationally bound NGC 3603 NGC 4755 NGC 3766 Arches Nora Lützgendorf, KAS16 30 / 49
Open clusters - Observations - ~ 2000 identified 1e5 within the Galaxy! (extinction) Globular Open Nora Lützgendorf, KAS16 31 / 49
Types of clusters N stars 100-1000 1e4-1e6 1e4-1e5 1e5-1e7 1e6-1e8 OB Associations Embedded Open Globular Nuclear Nora Lützgendorf, KAS16 32 / 49
Globular - 1-30 pc - mass ~ 10 4-10 6 MSUN - gravitationally bound - age: 10-12 Gyr oldest objects in the universe! Nora Lützgendorf, KAS16 33 / 49
Globular - 1-30 pc - mass ~ 10 4-10 6 MSUN - gravitationally bound - age: 10-12 Gyr oldest objects in the universe! Nora Lützgendorf, KAS16 33 / 49
Globular - Are dense DENSITY ~10 3 1/pc 3 SUN ALPHA CENTAURI Nora Lützgendorf, KAS16 34 / 49
Globular - Not what expected PAST: - All stars formed at the same time - All stars have the same chemical composition TODAY: (see Lecture 2) Omega Centauri, Bellini et al., 2011 Nora Lützgendorf, KAS16 35 / 49
Globular - Live in Galaxies Always around galaxies Milky Way Andromeda M87 ~200 GCs ~500 GCs ~15 000 GCs Nora Lützgendorf, KAS16 36 / 49
Globular - Specific Frequency Number of Globular in a galaxy divided by the galaxy s luminosity: S N = N GC /L G - Formation efficiency of Globular relative to field stars - Depends on galaxy type (higher in ellipticals) Georgiev et al., 2010 Nora Lützgendorf, KAS16 37 / 49
Globular - Bimodality BLUE RED Blue Globular metal-poor galaxy halo larger Red Globular metal-rich bulge/disk smaller Nora Lützgendorf, KAS16 38 / 49
Young Massive - Young cluster populations forming today - Maybe forming Globular??? - Formation Environments: Galaxy Mergers Spiral Galaxies Starbursting Dwarfs High Star Formation Nora Lützgendorf, KAS16 39 / 49
Types of clusters N stars 100-1000 1e4-1e6 1e4-1e5 1e5-1e7 1e6-1e8 OB Associations Embedded Open Globular Nuclear Nora Lützgendorf, KAS16 40 / 49
Nuclear - 1-30 pc - mass ~ 10 5-10 8 MSUN - age: multiple epochs of star formation - centers of galaxies - gravitational bound - co-existing with black hole - densest objects in the universe Seth et al., 2006 Nora Lützgendorf, KAS16 41 / 49
Nuclear - Are super dense DENSITY ~10 6 1/pc 3 SUN ALPHA CENTAURI Nora Lützgendorf, KAS16 42 / 49
Nuclear - Host black holes NGC 404 Seth et al., 2010 Nora Lützgendorf, KAS16 43 / 49
Nuclear - Formation 1.) Globular Cluster infall 2.) Gas accretion, star formation Nora Lützgendorf, KAS16 44 / 49
Nuclear - Formation 1.) Globular Cluster infall 2.) Gas accretion, star formation Nora Lützgendorf, KAS16 45 / 49
Nuclear - Multiple populations Sgr/M54 Siegel et al., 2007 Nora Lützgendorf, KAS16 46 / 49
Nuclear - Peculiar kinematics Nora Lützgendorf, KAS16 47 / 49
Nuclear - In our Galaxy Nora Lützgendorf, KAS16 48 / 49
Nuclear - In our Galaxy Nora Lützgendorf, KAS16 48 / 49
Nuclear - In our Galaxy Nora Lützgendorf, KAS16 48 / 49
Summary 1. Star : Collection of stars roughly born at the same time (sometimes gravitationally bound) 100-1000 1e4-1e6 1e4-1e5 1e5-1e7 1e6-1e8 OB Associations Embedded Open Globular Nuclear - in the disk - gravitationally unbound - in the disk - still gas left - in the disk - gravitationally bound - in the halo/ bulge - oldest objects in the universe - at the center of the galaxy - densest objects in the universe Nora Lützgendorf, KAS16 49 / 49