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Peculiar (colliding) Galaxies and Active Galaxies. Colliding galaxies tidal distortions, star formation, evolution (role of simulations) Active galaxies Beginnings – bright nuclei (Seyfert)
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Peculiar (colliding) Galaxies and Active Galaxies • Colliding galaxies tidal distortions, star formation, evolution • (role of simulations) • Active galaxies Beginnings – bright nuclei (Seyfert) • Quasar discovery - the, high redshift surprise • “Non-thermal” radiation (synchrotron +) • Models: supermassive black hole + accretion • Beyond the nucleus – radio galaxies & jets • Superluminal motion, blazars • “Unified” theories
COLLIDING GALAXIES Galaxies in collision/interacting/mergers Computer simulation – interacting pair The “Antennae”
COLLIDING GALAXIES M51 – the Whirlpool and companion
COLLIDING GALAXIES Evidence for mergers Distant Galaxies (large lookback times) – forming via mergers Ring of active star formation
COLLIDING GALAXIES Sgr dwarf elliptical merging with Milky Way
Seyfert galaxies – spirals with very luminous central nucleus strong infrared and radio sources Strong emission H, He, N, O Doppler broadened lines Carl Seyfert
In 1962, British radio astronomer Cyril Hazard used moon as an occultive shield IDENTIFYING THE OPTICAL COUNTERPART RADIO XRAY OPTICAL
3C 273 spectrum Martin Schmidt 7x1044 ergs/s !
Quasars – Quasi-stellar Object (QSOs) Central source so luminous appears star-like Radio/Optical/UV/Xray/Gamma-ray radiation
Giant elliptical M87 Cen A – radio emission M87 – jet from nucleus
Active Galaxies Strong radio sources Radio galaxies -- jets of non-thermal radiation – two-lobed appearance due ejection at high energies
Current work: PhD student Shea Brown Coma cluster of galaxies and radio “relic” from infall of galaxies into cluster Blue – radio WSRT Red – X-rays ROSAT Green – diffuse radio, GBT
The central engine for active galaxies, radio galaxies, quasars -- supermassive black holes 109 x mass Sun Our galactic center 106 x mass Sun http://www.mpe.mpg.de/ir/GC/index.php
“Superluminal” motion Relativistic almost along line of sight
UNIFIED MODELS Radio galaxy Seyfert galaxies/ Quasars Blazars