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part1 - Major Topics 1 Introduction Stars the Milky Way...

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Major Topics 1. Introduction Stars, the Milky Way, Other Galaxies, Cosmology 2. The Galaxy and its Components Luminosity/Mass Functions, Distances, Clusters, Rotation 3. The Interstellar Medium Gas, Dust, Emission and Absorption 4. Galactic Dynamics Gravity, Encounters, Epicycles, Boltzmann Equation 5. The Local Group 6. Spiral and S0 Galaxies Starlight Distribution, Gas Motions, Spiral Structure, Bulges 7. Elliptical Galaxies Photometry, Motions, Dark Matter, Black Holes 8. Galaxy Groups and Clusters Galaxy Formation, Intergalactic Matter and Gravitational Lensing 9. The Large Scale Distribution of Galaxies Cosmology, Growth of Structure 10. Active Galaxies and Pre-Galactic History Active Galactic Nuclei, Jets, Intergalactic Clouds, the First Galaxies J.M. Lattimer AST 346, Galaxies, Part 1
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Stars – Main Sequence Spectra metal 4000 ˚ A break CH H neutral Balmer lines H nearly totally ionized Balmer jump 3646 ˚ A Paschen jump 8250 ˚ A J.M. Lattimer AST 346, Galaxies, Part 1
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Stars – A Dwarf, Giant and Supergiant Spectra Effect of gravity on line width – the Stark effect broad Balmer lines narrow Balmer lines J.M. Lattimer AST 346, Galaxies, Part 1
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Stars – Basic Relations for Main Sequence Stars I Masses between 0.08 M and 100 M I Radii between 0.1 R and 25 R I R R M M 0 . 7 I L L M M 5 ( M M ) , L L M M 3 . 9 ( M 10 M M ) I L 50 L M M 2 . 2 ( M 10 M ) I τ MS τ MS , M M L L 10 Gyr M M - 2 . 5 10 Gyr L L - 5 / 7 I log( τ MS / Gyr ) 1 . 015 - 3 . 49 log M M + 0 . 83 h log M M i 2 I M V , = 4 . 83 , M B , = 5 . 48 , M K , = 3 . 31 , M I , = 4 . 11 I M bol , = 4 . 76 , L = 3 . 9 × 10 33 erg s - 1 , T eff , = 5780 K J.M. Lattimer AST 346, Galaxies, Part 1
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Abundances [ A / B ] = log 10 h ( A / B ) * ( A / B ) i J.M. Lattimer AST 346, Galaxies, Part 1
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Photometry Sky emission from La Palma A0 F λ F BP = R 0 T BP F λ d λ F λ eff R 0 T BP d λ F λ eff Δ λ BP m 2 - m 1 = 2 . 5 log 10 F 1 F 2 m BP = 2 . 5 log 10 F V , 0 Δ λ BP F BP F V , 0 3 . 63 × 10 - 9 erg s - 1 cm - 2 ˚ A - 1 m BP = - 21 . 1 +2 . 5 log 10 Δ λ BP F BP ’ - 21 . 1 - 2 . 5 log 10 F λ eff T BP ( λ ) J.M. Lattimer AST 346, Galaxies, Part 1
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Milky Way 4 × 10 6 M BH H I Disc stellar mass: 6 × 10 10 M Disc luminosity: 2 × 10 10 L Bulge stellar mass: 2 × 10 10 M Bulge luminosity: 5 × 10 9 L Halo stellar mass: 1 × 10 9 M 8.5 kpc J.M. Lattimer AST 346, Galaxies, Part 1
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Gas and Dust in the Milky Way I Solar neighborhood: 1 star per 10 pc - 3 , 1 atom per cm 3 I H II region: ionizing photons λ < 912 ˚ A, E γ > 13 . 6 eV I Emission timescale typically 10 - 8 s I Collisional excitation A + B A * + B , A * A + h ν I Forbidden line: collisons rare (gas density low), timescale 1 s I Fine structure transition: spin-orbit coupling in atoms, 1 / 137 2 less energy: far-infrared I Hyperfine transition: nuclear spin coupling with electron spin, 2000 times less energy than fine structure: mm and radio I Spin flip 21 cm radiation of H I. Takes about 11 Myr to spontaneously transition to ground state. Collision times of order
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